Wednesday, December 31, 2014

Spanish Sparks....A History of Frustration

I have a very mixed history with Bultaco ignition systems. My first Bultaco was one of the original 100cc Lobitos. I was able to start it with the kick starter for about two weeks. After that I stopped even trying...I just paddled it down the street until it fired. A little frustrating and more than a little embarrassing. I was expecting my new (to me) Campera to treat me the same. Sure enough it stopped starting.

I really can not say that the stock system was at fault. It may well have been that the Mikuni suffered some sort of failure, but I was determined not to have to worry about sparks again. If I have to ultrasonically clean a carburetor, or re-jet it, or adjust the idle....fine. I just don't want to be worrying about whether or not I am fixing the system which is at fault. It is reassuring to know that the ignition system is working. I was never sure with the stock system.

The solution came in the form of a German system from Powerdynamo. It is a beautifully made system which can include an AC power source for a rudimentary lighting system. I got the system that had the 2kg rotor. There is a lighter rotor for the Pursangs. It is not a particularly inexpensive solution (about 289 Euros including a puller) but it is the only option for the older 4 speed Bultacos.

The installation was very straight forward. You just remove the old points system which lies behind the flywheel and replace it with the Powerdynamo stator. As can be seen, it is a beautiful piece. Five wires lead from the stator. Three go to the coil and two go to the AC regulator. Very high quality wires and insulation where the wires exit the case. You would be hard pressed to screw up this part of the installation.

The rotor, on the other hand presents some interesting challenges. The instructions that come with this unit indicate that you will not be using the woodruff key that locates the Bultaco flywheel/rotor. when you install the Powerdynamo rotor. how do you time this thing?

Etched on the outer face of the rotor is a thin black line. Again, according to the instructions, when this line crosses the blue mark on the stator, ignition ensues. There are two problems. First and most obviously, there are two blue marks on the stator. Take a look at the picture below. There is a very prominent blue dot on the mounting plate, and then a somewhat fainter mark on the gold plate just to the left of the windings which generate the spark. Which one to use? I elected to use the obvious dot.

The second problem is that the rotor is somewhat difficult to attach to the crank at exactly the place you have selected. Assuming that you have used your dial gauge to locate the optimum point where you think that ignition should occur, the challenge is to place the rotor on the crank at that exact point and then tighten it down without disturbing its location. Trust me...this is not easy. The magnets on the rotor want to move the rotor around, and when you attempt to tighten it down...again, things start moving around. If you invest in this unit, be sure to buy the puller. You will have multiple opportunities to use it.

After multiple installations I was finally able to set the timing at about 2.5mmBTDC. I also got after the Mikuni carburetor with my new ultrasonic cleaner....and, just to be on the safe side, I mixed-up some new pre-mix. Success at last! It fired up literally with the first kick. I have gone out on several rides in the 10+ mile range and it runs perfectly. How cool is that?

The next challenge with this system is to create a lighting system...not so I can go out riding at night, but just in case. Even here in Mexico you are required to have a working stop light. My longer term goal is to participate in the occasional giro and  I know that these events require a street legal motorcycle.

The next project for this bike is to install and tune the Wassell carburetor that I just picked up from Hitchcocks. It is pre-jetted for a 175cc BSA Bantam so I am expecting it to be pretty close. I picked-up this unit for purely esthetic reasons. The adapter that I have to use to fit the Mikuni to the Bultaco is unsightly and there is virtually no room left for an air cleaner. With the Wassell carburetor I can bolt it directly to the Bultaco manifold (2" center to center mount) and the original Bultaco air cleaner screws directly to the carburetor body. Wish me luck! 

Thursday, December 11, 2014

Once Again....Apart

You know...a two stroke engine is blindingly simple. No pushrods, no valve shims, no camshafts, no complicated chain or gear drives to the camshaft, no valves, no oil pumps, no oilways to get clogged up, etc....You would think that this unit could have been rebuilt with little drama. Unfortunately, in my case that was not to be.

It turns out the the "carburateur diabolique" was not the problem. My first assumption was that the carburetor (which spelling should I use??) was simply not working. I got an overhaul kit from TY Trials and an ultrasonic cleaning unit. The overhaul of the carb was uncomplicated and both purchases made good sense. Unfortunately when the newly overhauled (and very clean) carburetor was installed it made no difference whatsoever. Still...wild revving at almost any throttle setting and complete chaos when the choke was pulled out. However, I did notice a strong blast of air on the left side of the engine case in the vicinity of the cylinder base gasket....which also sent me down the wrong road.

I pulled the cylinder off and installed a new base gasket and sealant and a new head gasket. I assumed that there was an air leak somewhere at the base of the cylinder. Again, frustration. The wild revving continued.

Next,  I pulled the cylinder off again expecting to find a cracked cylinder or a crack in the case somewhere. No obvious problems could be seen, but I did notice an excessive amount  of dark and heavy oil in the transfer ports. That is when the light finally went on in my head. The seals on the crankshaft had failed. On the drive side, the seal failed and it was pulling in both air and oil. On the magneto side, the failure of that seal was pulling in pure air. The leak on the magneto side explained the air movement on the left side of the case. Air was being drawn in at the opening which was provided for the wires from the magneto.

The fault finding is easy. I am the problem. On the magneto side, it appears that I installed the seal backwards. Hard to believe, but that seems to have been the problem. May be I started drinking too early that day. May be the light was insufficient. May be I was distracted. May be I was in too great of a hurry, whatever the reason the fact is that when when I pulled off the rotor, the little springs which hold the seal tight against the crank were free from the seal and wrapped around the rotor itself. On the drive side, it appears that the seal was damaged during installation. I do remember that both seals were aftermarket pieces that had come with the bearings. They were very difficult to install. It appeared that they may have been slightly oversize. I have ordered new Yamaha OEM seals from John Crane at TY Trials.

Above is a shot of the drive side main bearing seal. This is not the seal that failed. Actually the design of the on this side of the crank employs three different seals which, if properly installed, will provide a comprehensive seal. There is a double lipped seal mounted in the crankcase and that seal rests on a sleeve which fits tightly on the crank and which has a further seal between itself and the crank. I must have made a mess of this seal when I put the cases together. I can see now, working with these seals on the bench that it is not an easy job. The sleeve which goes over the crank case must be installed in a way which will allow the lips of the crankcase seal to fit tightly over the sleeve without folding under. I will be more careful next time.

Stay seals will be arriving from England in the near future. I will get this engine together!

Saturday, November 29, 2014

Bultaco Art-Look At What You Find When You Are Cleaning!

This particular piece of industrial art appeared to me while I was performing some long overdue maintenance on my Bultaco Campera. Art really is wherever you find it. Sr. Bulto and his designers created some pieces which go well beyond what was required or needed. Other pieces, not so much, but beauty can be found through these bikes.

I had been riding the bike around the beaches and muddy flats around my home. Dirt and mud and a  mixture of sand and salt had created an exceedingly ugly coating on the front end of the bike. Maintenance had been delayed by more interesting projects, i.e. the TLR and the TY.

Luckily a lull presented itself while I was waiting for pieces to be delivered for the TY. It was an opportunity to refresh the Bully.

This is what the fork looked like before I began cleaning and polishing. It looked a lot worse than it really was. It was just a matter of applying a wire brush to the worst of it and then some sandpaper and then some metal polish...Simichrome...a German product. The fender and the fender brackets received the same treatment. And, by the way, I can see the's on the list.

This is obviously another shot of the front hub. If you have an older bike do yourself a favor and look at the pieces closely. You will find some beautiful pieces on your old bike. Look will be surprised.

Tuesday, November 18, 2014

TLR Exhaust Up-Date

 A month or so ago, I spent some time on this blog whining about the unsuitability of a couple of aftermarket downpipes which I had picked-up for the TLR. My complaint was that they did not fit.

As usual, especially with things mechanical, I was wrong. The fault was mine. After I had installed the WES system (which I had been using for several years) with the stock down pipe I went for several rides and a couple of weeks ago, I decided to give it another go...just to see if the new down pipe would work.

In fact the Delkevic Down Pipe installed perfectly. It has a little mounting point on the side to which a guard could be mounted. I have not seen anything which might work, but then again I have not really checked out their website. May be one of those little guards that are seen on older Triumph up pipes would work....We will see.

Just a note on the performance of the bike. It is working perfectly. The lower gearing makes it easier to get the front end up in the air to get over ledges, and the new rear Dunlop Trials tire makes a noticeable difference in rocks and deep sand. Given the problems that I have had with the TY, it is comforting to be able to go to the garage and know that I can go for a ride anytime I want....Thank you Soichiro Honda. The bike may be a little heavy, but it starts and runs every time.

Le Carburateur Diabolique...

The TY has been a source of significant frustration over the past couple of weeks. As you can see, the bike is finished, but essentially unrideable unrideable. The more perceptive among you will notice the lack of a chain, but that is not the problem.

The real problem is the carburetor. It is possessed. When I stuck the bike in the back of my garage (10+ years ago) it had multiple problems. One of the problems was that it would only run at hysterically high revs. It would not idle and it was not very interested in starting. Those same problems exist.

First I suspected a massive air leak into the cylinder. So... I removed the cylinder and applied a seal to the base gasket. I also went through the intake manifold/reed cage assembly and again I checked for leaks, and/or torn rubber in the manifold and then I applied a sealant to the gaskets and reassembled.  After all of this, there was no change...hysterical revving persisted so I disassembled the carburetor and cleaned out the idle jet and the main jet. Both appeared to be free from obstructions. I started it up again, but no change...hysterical revving persisted...something was clearly wrong, and it appeared to be beyond my limited skills.

I'm going after this problem on two fronts. First, I have a spare Chinese Mikuni carburetor which I initially picked-up off of eBay for my Bultaco Campera. Dimensionally it is identical to the Mikuni which is presently fitted to the TY (it is the original carb that came on the bike). This carburetor will be installed if my rebuild of the stock carburetor does not help. The rebuild of the stock carburetor will begin just as soon as I get the gasket/seal set from  TY Trials and my new ultrasonic cleaner. I am going to figure out this carburetor.

On a happier note, I have solved the kick-start problem, the new gas tap works perfectly and the Electrixworld ignition appears to work as advertised.

So...I am going to learn how to rebuild and properly clean my carburetor, and if I am just too thick to get that done, I will install a new carburetor. One way or another I am going to ride this bike. It is way to beautiful to set quietly in the garage.

Saturday, October 18, 2014

The TLR is Done!

Finally, I pushed this project through! It took at least two full days to finish it up..check everything several times and then go for a little ride. This last stage was not without its problems.

First and most disappointingly I was unable to use either of the stainless headers that I had bought from two separate sources. First was the relatively inexpensive unit made somewhere in the East (either India or Thailand). The second unit was more expensive and better finished. Unfortunately neither unit would fit. As you can see my TLR has the WES system which, by the way, fits perfectly with the OEM Honda unit. So...if either of these suppliers had made a faithful copy of the OEM header, it would also fit perfectly. Unfortunately, that was beyond their expertise and so I am left with the scruffy OEM header. I was really hoping to replace it with a nice shiny stainless piece.

The seat/tank unit was also an issue. The original gas tap which came directly from the original Reflex tank was starting to leak and so I again went to eBay looking for a replacement. Again I ended up in the Thailand section where I found a replacement. When I went to install the gas tap, the tank was already on the bike. Then I threaded the new tap on and began to tighten. With no really good point of reference I managed to start tightening before the tap was exactly on straight. In short, I cross threaded it...and continued tightening until I had buggered at least three threads.

My first line of attack was to use my die set to try and clean up the threads. That turned out to be impossible because there really was not enough clearance between the tank and the feed pipe for the die to sit perfectly on the buggered threads. So I choose to cut off the buggered threads....again, not easy. A hacksaw would not fit in that area and so I ended up using the hacksaw blade by hand. It took a while. The next problem with this "fix" was the fact that the hand made cut had to be at 90 degrees to the feed pipe or the tap would not seat fully. Yea, what are the chances of that happening? As you might expect, the cut was not at 90 degrees and so I had to use a file to get it as close as possible and then I made a thin rubber gasket to take up any slack. It is now leak free.

Mounting a new tire is always a pleasure. Actually mounting this Dunlop trials tire was less troublesome than most. The carcass is more flexible than most tires and the higher profile of the tire allows me, more easily,to get my hand inside the tire to situate the tube and the rim lock.

Naturally, there was a new chain and sprocket set. I went one tooth down in the front and two teeth larger in the rear as well as one size stronger (plus o-rings) on the chain.  Lowering the gearing on this bike seems to be a standard improvement made by the trials community. In my case I am not sure that the lower gearing will not be off-set by the larger and heavier tire. We will see.

To suit the stronger/wider chain the sprocket is somewhat thicker. Since the original sprocket is held to the hub with a snap ring I expected that there might be problems....but I also remembered that the original rear sprocket had a spacer behind the sprocket facing the hub. So it all made sense. I simply installed the sprocket without the spacer and it aligned perfectly with the groove for the snap ring. Obviously Honda uses this hub for a model that employes this larger (thicker) sprocket.

Yes, I know that this drive chain is significant overkill. "Real" trials guys would never use o-ring chains, and they might even go down a size on the drive chain. In my case, I managed to break the stock chain in deep sand which left me with a five mile hike in my riding gear to get home. I really do not want to repeat that experience.

The improvements made to the bike were primarily cosmetic. Any performance improvements would be related to the new tire and gearing combination. The seat/tank unit was painted. A seat pad was also installed. This pad came with the seat/tank unit but I had never glued it down because I knew that I would only have to rip it off when/if I painted the seat/tank unit. New bars and grips were installed. New fenders were installed and virtually all of the fasteners were replaced with stainless nuts and bolts and virtually all of the nuts were of the nylock variety. One major improvement was that every bit of salty/crusty Baja sand and dirt was removed. Corrosion and rust was stopped in its tracks.

The test ride was uneventful. I just wanted to make sure that I had not missed something that was going to cause me great bodily harm. As it turns out, I had apparently tightened every nut and bolt and checked every clearance. Next up will be a longer ride to my favorite places to see if the change to the gearing will have any useful effect.

As a point of reference, below is a shot of the TLR before this project was initiated. Don't bother to click on the picture. It is a low resolution picture that I created for some forum...probably Trials Australia...which requires a lower resolution photograph for their threads.

Here in the workshop my next project will be to complete the TY. Below is a shot of it in its current condition...really not much more to do. It needed a base gasket (which I now have). That's what caused me to shift gears and complete the Honda. All that's really left is to install the cylinder and head, exhaust system, carb, air cleaner and the ignition system. The seat is with our upholstery guy who is making new covers for our cushions in the patio which were wiped out in the hurricane. A bunch of new pieces have arrived for the kick start mechanism, but I am not going to install the new pieces until/unless the unit again fails. The TY could be finished in a day. I am anxious to see how much better a bike the TY is as compared to the TLR. It has been a long time...probably ten years...since I rode the TY.

Watch this space!!!

Monday, September 29, 2014

There was this storm.......

Two weeks ago, we were hit by this monster. We only got our internet and electricity back yesterday. Apparently the wind speeds in La Paz (where we live) were 125mph+. Our home has a palapa roof (palms) and there was some damage from the wind and the rain (6") Most of the news coverage in the United States was focused on the resort city of Cabo San Lucas. We live about 100 miles north of Cabo San Lucas and we got the same storm. It went directly north through Baja.

Luckily for me, but not so luckily for him, my son and his girlfriend arrived in La Paz the day before the hurricane arrived. The intention was to spend a week riding dirt bikes and generally catching up on things. It ended up being a week of cleaning up and scrounging around our stricken city for ice and food. Believe me, if you find yourself in a disaster area there is absolutely nothing more useful than a couple of 29 year olds who love to help. They will be back in a couple on months to have that vacation they had in mind.

Prior to the storm, this is as far as I had gotten on the project bikes. The TLR really just needs to be reassembled and the TY just needs the top end stuck on. My plan was to get these last few tasks accomplished with my son during his visit. The Hurricane blew up that plan. Nevertheless progress has been made. As far as I know I have all the parts on hand to finish the bikes and figure out if they will start and run. The seat/tank units on both bikes look good and the alloy fender on the Honda is just what I was hoping for. I finally figured out that I could attach the alloy fender to the tupperware fender which was already in place.

As the followers of this blog might remember, the point of building two bikes simultaneously was so that when my son came down to visit we would have two new bikes to shake down. I had a bit of a deadline, i.e. September 13. The cool thing about a self-imposed deadline is that nothing really happens if you miss it. In my case I just rationalized that it might be more fun to complete the bikes together. That did not work out. We ended up cleaning up after a hurricane....which was, in and of itself a bonding experience. Well, now I've got a new deadline....sometime in December/January or February when he will come back with some friends to go riding. Wish me luck.

Monday, September 8, 2014

Constructum Interrumptum

It has been a bad couple of weeks for both of the project bikes. The TLR (above) was coming together very nicely. This was mainly a cosmetic project and so I was not anticipating any impossible stumbling blocks. About two weeks ago the seat tank unit was ready for its clear coat. The Honda wing was in place as well as the NGK decals and the HRC decals. I set the tank up on my short ladder (which I use to support things that I am painting) and began applying the clear. It was going on so well, I barely took a break between the first and second coat. About five minutes into the project I realized that the HRC decls were dissolving which was going to make about three more days work for me. By the way, I absolutely knew and understood that I needed to give the HRC decals a mist coat first and allow that to thoroughly dry before applying any more clear. Again, it is very frustrating to sabotage your own projects.

My next mistake was to bump the ladder which was supporting the seat/tank unit. That particular move sent the unit on to the ground causing even more damage since the clear was still very wet. It was a bad couple of minutes.

Now I needed to order a couple more Honda decals. This moved the project out about two more weeks...leaving me plenty of time to sand and re-paint the seat/tank unit. I am currently waiting for the delivery of the Honda decals. My last couple of deliveries have been delayed by a hurricane raking the west coast of Baja.

The next disappointment was the TY. I had a nice morning getting the gap on the rings just right, and then I spent a bit more time measuring the re-measuring the piston clearance. I was ready to go. I went to get the base gasket when I realized that I had never seen a base gasket, despite the fact that I had ordered and received two gasket sets from two different sources. I am the idiot for not checking. Nevertheless, it is a little disappointing that these two suppliers would send out two gasket sets without a base gasket. By the way, both of these same suppliers failed to supply a gasket for the clutch side side case cover. Again, my bad for not checking. So, I have had to order some base gaskets from a supplier in the United States. May be I will get them in a couple of weeks.

The TY was also stalled for a week or so while I tried to sort out problems with the kickstart unit. After spending some time on the Trials Central Forum-Yamaha Specific Forum I really did not conclusively solve my problem but I did discover what the problem was and I figured out that by adding a couple of appropriately sized washers to the kickstart shaft between the spacer and the inside face of the clutch side case the problem was solved. My problem was that the stop on the inside end of the kickstarter shaft was riding up and out of the recess provided for it by the right side center case. I have ordered a bunch of new pieces from TY Trials. Mainly the shaft itself and the sliding gear. I really do not know what else to do. No one has explained to me how the shaft can ride up and out of that recess, but I did figure out how to stop it happening. May be that's enough.

Friday, August 15, 2014

Results You Can See...

Finally, something that looks like a real motorcycle that you can least that's my hope. I spent a couple of hours today...between thunderstorms...assembling the chassis. I would call it a huge improvement from what I started with a couple of months ago. See that dirty beast below.

Above, obviously, is the "before" picture. I wonder if Sammy Miller could be persuaded to offer his seat/tank units in the yellow bumble bee style rather that the white gel coat. I know that you Euros are used to the white/red color (colour?) combination on your TY bikes, but I have to say that this is an improvement. Who doesn't like the Kenny Roberts North American color combination??

Above is a detail shot of the rear fender mount. Again, this is not the sort of thing that you might see at the SSDT. At least not on a Yamaha. If you have been following this blog, you know that the welding was done by a good friend who has essentially no experience with motorcycle frames, but a lifetime of experience with metalwork. I am lucky to know Chuy.

Above is a detail of the triple tree..or steering stem...or yoke..I guess that there are a lot of different terms to describe this part of the motorcycle anatomy. As you can see, I am free with my use of drilled, oversize, alloy washers. I like them. I like the look and I am perfectly aware that they are not necessarily the first choice of "serious" trials enthusiasts. Well, truth be told, I am not one of those guys. This particular motorcycle will not have to be pulled out of a freezing Scottish stream or pulled off of me after we have tumbled down a slippery slope. The intended use of this bike is to simply cruise the beaches and river beds of Baja California.

More to come, probably this week. The engine cases are together and I simply have to add (and re-check) the clutch, ignition, kick starter, and the shifting shafts. Again, so many, many ways to screw this up. Pray for me! See you soon!

Saturday, August 9, 2014

The Paint on the TY is Done!!!

Yesterday I put two more clear coats on the seat/tank unit. About a week ago I finished the yellow paint and I was able to look at my choices for the decals. These decals, which are actually for a YZ from the 70's, looked best. They are similar to the decals that came on the unit from Sammy Miller…only a little more aggressive. Later today or tomorrow I should be able to put the entire chassis together and see what it looks like with the alloy fenders.

As you can see in the background, work is moving forward on the TLR. It now has several coats of primer and paint on the seat/tank unit, but the frame is untouched. The frame needs to be comprehensively cleaned and then some primer on the parts of the frame that have been rubbed down to bare metal.

I also get to chase around to the autoparts stores and/or the radiator shops to find some radiator hose for the WES exhaust. There are two joints that I want to cover with hose….and I get to have my old seat reupholstered by a local shop. In this part of the project I am lucky. Reupholstery shops are plentiful, cheap and the work is excellect. Adios for now, the next pictures will be of a complete chassis.

Friday, August 1, 2014

The TLR Comes Apart...

Over the past couple of days, weather permitting, I have been working on the TLR to get it to a point where I can give it a good cleaning, re-paint the frame and bodywork, and replace the more vulnerable fasteners with stainless. The humidity and the salty soil is causing a great deal of corrosion on the fasteners associated with the frame. Work has been slowed by the extreme humidity and heat. The temperature in my garage was 102 degrees when I shot the above picture.

Today the engine came out...but not without a fight. The engine is a tight fit in this chassis. I have no idea how I am going to get the clean engine back into the newly painted chassis without tearing up a lot of the new paintwork.

Now, I have a new problem. I need to take the chassis apart...wheels, forks, shocks, and swingarm all need to come off for cleaning and paint. How am I going to support the frame in order to remove these components? I woulod like to put it on a simple aluminum stand, but that's not an option. I am open to suggestions. Hanging it from the rafters seems like a good idea, but I do not have any rafters. The roof of the garage is cememnt. What do you TLR guys do???

The TLR...

May be it is a good idea to begin the TLR before the TY is done, may be not. What I am trying to do is complete both bikes before the first week of September when my son is coming down for a few days. It seems doable if I can stay focused. If I can not keep up, neither bike will be done. So, let's see what happens.

The TLR 200 is more than just a TLR. It is a  Reflex which was originally imported into the United States. As you Honda guys know, this means that the engine was virtually unusable because of the strangled carburation and the chassis was burdened with a battery which was actually carried like a saddlebag on the right hand side of the bike. Excess weight was everywhere. After I bought the bike I did the basics to turn it into a useful trail bike. The very first thing that I did was to re-wire the thing to eliminate the lighting system, turn signals, battery, and instruments. Secondly, I mounted a seat/tank unit from B & J Racing a supplier in the United States. Next, I got some new shocks and handlebars and a WES exhaust from the same supplier. These changes helped, but the bike was not really transformed until  I mounted a Chinese copy Keihin carburetor. The Chinese Keihin made all the difference...actually the carburetor made more difference than anything else that I did to the bike.

This time the TLR is just going to get a cosmetic overhaul. All of the mechanical bits are working as well as can be expected for a trail bike. But being used constantly in the salty environment of the beaches here in La Paz has taken its toll. There is an unacceptable amount of rust around the lower frame and the swing arm, and the paint is disappearing at an alarming rate. As you can see in the photo above, the seat/tank unit has never been painted, and it has a nice crack on the rearmost edge from me sitting there when I got too tired to keep up the trials posture. I hope to mount alloy fenders front and rear, but mounting a rear alloy fender has its challenges. We will see.

As of this moment, the seat/tank unit is on the work bench being cleaned-up after the repairs to the rear lip. Later today, I expect to apply the first coat of primer.

Tuesday, July 22, 2014

Paint is going on...

I have not been posting much recently about the TY. I have been making progress, but the problem is that once I get into the garage I just tend to get to work instead of taking pictures and documenting what's happening. So, here's an up-date.

Painting the frame with a touch-up gun is difficult, messy and wasteful. In the future, especially if I am somewhere near a shop that can sandblast and powercoat I will go in that direction. This frame has numerous nooks and crannies which are virtually impossible to reach with a spray gun. Naturally the overspray goes everywhere. There is a lot of wasted material. Finally, in frustration I got a couple of rattlecans to finish the job. Otherwise many small tabs and mounts were not going to be adequately covered. Today I applies a couple of coats of clear to try to bring out a bit of a shine. It looks successful on the main tubes.

I have to keep reminding myself that this is a trials bike...a bit of a gentleman's trials bike..but still a trials bike. It will get very dirty and it will spend more than a little time on its side in the dirt. No sense in going crazy on the cosmetics.

The tank was significantly easier. The touch-up gun hold enough paint for two coats. So far the tank has about four coats and has only had a tiny bit of sanding in between the coats. I ordered a couple of set of decals off of ebay today which are supposed to be suitable for a middle 70's other words, bumble bee stripes.

Once I have figured out the decals I will clear coat them. While waiting for the decals, I will check and double check the assembly of the engine and install it into the frame...then the suspension and the wheels and I will be done. Can't wait!

Just some routine maintenance...

As I mentioned in an earlier post, the old Amal has been switched for a Chinese Mikuni. Subsequently, I've attached a foam filter to keep the worst of the grime out of the carb. Now, with the new carb in place, I am riding the bike a lot more. It is nice to just sit in the saddle and explore the Baja beaches, as opposed to my usual stand-up stance on the trials bikes.

The experience is really improved by the fact that the bike now idles...what a treat, and it is significantly faster and cleaner on the top end. Anyhow, from the beginning  there has been a steady and very low volume leak from the primary case, nothing unusual for a Bultaco and actually it is comforting because it means that there is oil in the primary case. I had been adding smallish amounts of oil before each ride to insure that everything was well lubricated in there, but it was time to change the oil and conduct a little inspection.

I have to say that it is a real treat to work on a bike that has been properly looked after. The seven allen head bolts which hold the primary side cover to the case were in perfect condition. They all had washers, and they were tightened to the correct torque. Not crazy tight...but tight enough. The primary case gasket was in place and it had not been coated with gasket cement so it could be reused. And, none of the threads in the center case were stripped.

300 cc of fresh 10wt. oil and I was done. The filler plug was undamaged and the drain plug was, likewise, in perfect shape. After a quick wipe-down I was off for a short ride around the neighborhood.

Friday, July 11, 2014

Trial Fit on a Trials Bike....

The frame has been given a couple of coats of primer. I am still not happy with the look of some of the joints so there is probably some additional grinding to be done. However, this was a convenient point to trial fit the WES exhaust and the rear fender. It went together very nicely.

The various bits and pieces of the exhaust system are made of fairly soft (but thick) aluminum and so I was able to bash the required clearance in the muffler where it passes close to the shock mount and the expansion chamber itself need a few hardy whacks to clear the frame. To my eye, it appears that the muffler will just clear the rear tire at full travel.

Next I have to go to the biggest auto parts store in La Paz and see if they will let me play in their radiator hose section behind the counter. I need a piece to connect the header pipe to the expansion chamber and another piece to connect the expansion chamber to the muffler. Both of these joints are a nice tight push fit, but I want the added security of a nice rubber joint to keep the drool and vibration to a minimum. Besides, all those rubber joints remind me of my Bultacos (both in the present and the past).

This trial fit was also an opportunity to create the reinforcing rivets and aluminum sheet for the rear fender. I'll post some pictures after I have had an opportunity to grind and file a bit. Right now it looks a little rough.

Friday, July 4, 2014

A (Chinese) Mikuni for the Bultaco

As I mentioned some time ago, my 175 Campera came with a very old Amal carburetor. It really was not interested in idling and acceleration usually brought forth a lot of stumbling which took a while to clear. It started well from cold, but was entirely disinterested in starting when warm. Apparently this set-up was originally intended for a Mercurio which had a 25% larger displacement. I love the bike but the Amal was in the way.

Solutions are available. In this case I simply did an ebay search for carburetors for a DT 175 Yamaha and this little beauty turned up. The results naturally included genuine Mikuni's which were priced in the $100+ range. This one was $26.00 plus shipping. I bought two with the thought that I might want to use the second one for my TY 175. I have to admit that the machining is not up to the standard of a Japanese Mikuni and the general fit and finish is clearly one step below the original.

Mounting this carburetor to the Bultaco really was not a big deal once I figured out where to get the right pieces. There are lots of rubber mounts available to fit a Mikuni carburetor to the Amal mounts, but they are sized for the larger Mikuni's. These rubber mounts are obviously intended for the larger British Twins and Singles. The mount this carburetor to this smaller bike I had to source pieces from Speed and Sport which is a United States supplier. I would expect that these similar pieces would be available in either the UK or Australia. Below is a photo of the pieces necessary.

I had to source the nuts to make it all work. I needed two M8X1.25 machine screws to attach the alloy adapter plate to the original manifold and then two more M8X1.25 socket head bolts to attach the rubber  adapter to the alloy plate. Not overly complicated if you can figure out where to get the pieces.

One last complication with this carburetor is the longish cable guide which comes out of the top of the carburetor and is intended to guide the cable into the body. This guide is threaded but it has no mount for the throttle cable itself. If you have a lot of old carburetors around you may have a receiver for the cable guide, otherwise you are back on ebay trying to find the right words to do a search.

The final hurdle is the throttle cable itself. The cable guide is unusually long and so you will probably need to shorten the outer throttle cable a couple of inches, or you will have to make your own. In my case I got a throttle cable kit from Venthill (which is UK based, but has a U.S. distributor) and made my own. Making your own throttle cable is not easy. It is not something that can be done with a hacksaw. These cables are incredibly strong and will only yield to something mounted on a Dremel tool. One more word of advice, do not ever solder in your bare feet. Don't ask.

The carburetor completely transforms the bike. It idles, apparently forever...even on the sidestand. It accelerates cleanly and returns promptly to idle when you release the throttle. Unfortunately, it is not interested in starting...either cold or I have some work to do. Right now, I just have to squirt a little starting fluid into the carburetor and away it goes. I'll keep you informed.

Thursday, June 26, 2014

Back to the Bare Frame...

A week or so ago, I visited my friend Chuy so that he could place two additional fender brackets on the rear frame loop to secure the alloy fender. What I forgot was that I also needed a new bracket for the WES exhaust system. So it was back to Chuy's shop. Above is a photograph of Chuy at work...very lightly processed with my HDR program.

While Chuy was finishing up this bracket he suggested that I might want to add some new bracing around the swing arm. The problem was obvious. On the right side, the bracing had been removed (I can not possibly understand why...) and on the left side the bracing is present but it appears to offer no support or functionality whatsoever. It looks like the sort of perforated metallic ribbon that you see holding up plumbing under your house. Chuy fixed that oversight with two new braces which will genuinely make the area stronger. Unfortunately, the gauge of the metal and the heavy handed welding lend kind of an agricultural feel to the new pieces.

The bracket for the exhaust system was an entirely different matter. Chuy found some lighter gauge steel and the weld was significantly more delicate.

Today, I cleaned up the welds and removed a couple of the original brackets which have no purpose with the addition of the alloy fender and the Sammy Miller seat/tank unit. All that is left is to once again thoroughly clean the frame and get some primer on it before all of that bare metal starts turning a rusty red. I expect to have at least a couple of coats of black lacquer on the frame within the next couple of days.

The amount of work and sweat I have put into this frame over the past couple of weeks, and before counting the initial stripping and cleaning, makes me a little jealous of those guys you read about in classic bike magazines that simply send off their old frame to a power coating firm and receive back a perfect glossy frame a couple of days later. Is that better? Or is that cheating? Of course it's not cheating, but this is hard work!

Saturday, June 21, 2014

Making Sparks...

For no particularly good reason I choose to install an electronic ignition on the TY. Visions of giant blue sparks danced through my head...effortless starting...a dead reliable idle, etc....Well, here is the reality. My United States based supplier in response to my order for an "electronic ignition" sent the Electrex World unit. As I have discovered on various forums all over the world, these guys have a very patchy reputation for customer service. In fact, I am told that they recently simply dropped their customer service telephone number.

At any rate, in my case when I went to install the unit I was immediately faced with the mismatch photographed above. In my case, a customer service telephone number would have been worthless. Even the offer to exchange the unit would have been expensive and time consuming for me, so I took the matter into my own hands...actually I had some assistance from my trusty Dremel tool.

As you can see above, I removed a miniscule amount of material from a structurally unimportant locating tab on the engine case. The result is that I can now comfortably fit the Electrex World Unit.

Now my main concern is that the unit has been designed/assembled in a similarly cavalier manner. I have read very good reviews of their products and many people have had good success with this unit. But I'm going to have to wait until the engine is finally installed in the bike to see my big blue sparks.

Thursday, June 19, 2014

A Matter of Style

Virtually every trials bike built since the mid 1960's features tupperware fenders. If you are regularly throwing yourself and your bike against granite escarpments these plastic fenders may be a good choice. I don't care for them and my riding style doesn't require such levels of indestructibility. I am, more or less, just cruising around the gentle desert landscape of Southern Baja, with an occasional trip down a rocky wash or up a sand dune.

As a simple matter of style, I vastly prefer the pre-60's look of the polished alloy fenders. In addition, and again purely as a style decision, I am reinforcing the fender mounting points with a second layer of aluminum sheet and exposed rivets. Below is a photo of the front fender which I mounted about a month ago.

The rear fender mount will be handled the same way. I like the look of the exposed rivets. Anyone who unfamiliar with this style should Google the term "steampunk". A little of this goes a long way, but it is reminiscent of the big singles of the 50's and 60's.

For my next project, I need to mount the engine, or at least the engine and cylinder head so I can mount the exhaust and then have Chuy build a hanger for the muffler. I will have more and better pictures at that time. Thanks for checking in.

Retirement and a New Rear Fender

This project has slowed over the past couple of weeks. The main reason is that my retirement had been temporarily called off. My partner, wife, best friend and lover departed on a one week tour of the United States. Visits to Connecticut and San Diego were on the schedule. That left me in charge of the household, which includes dogs, a bird, plants, a pool, and all of the work associated with maintaining the place. Nothing overwhelming...but more than I was used to. A way to keep things moving was to get some help. In my case, this involved my good friend Chuy. Chuy is a local artist in metal. He has made gates and doors for our house and for many of our neighbors. His work is beautiful and beautifully thought out.

Above is a shot of Chuy in his lair....a somewhat disheveled, dirt floored shop. He is about to make a couple of tabs to weld to the subframe of the TY to mount the aluminum fender. As you can see from the photo below, it is hell for strong. The tabs still need some more grinding and shaping but, for sure, this fender is not going to fall off.

My next project on the frame is to remove the fender (for the umteenth time) to remove the tabs which previously located the tupperware fender and the original stock side panels. My buddy has returned so I should have some more time in the garage.

Saturday, June 7, 2014


I remember back in the 60's reading an article in Cycle (a long defunct magazine) about how to set the timing on your Bultaco with a nail. As I recall, you bring the engine to TDC, put the nail through the plug hole and make a reference mark against a fin. Then you back the piston down 2.00mm (more or less) and make another scratch on the nail. Then you just put a piece of cellophane between the points and adjust the impossibly small screws which adjust the points through the impossibly small holes in the Bultaco flywheel until the cellophane is released just as the timing mark passes your reference. What could be more fun??? Actually if you are sitting alongside the road with a mis-timed Bultaco this might be useful information.

In fact the whole mechanical experience is massively enhanced by using the correct tools. Above is a quick shot of some tools I put on the bench to demonstrate. The torque wrench, micrometers, feeler gauges, snap-ring pliers, flywheel pullers, gear pullers and a Dremel tool are really indispensable  in a project like this....and, none of this stuff is massively expensive. Start your collection now kids, you will be using this stuff until all the bikes are electric...did I mention that you might consider purchasing a multi-meter???

For the last couple of days I have been installing the seals and trial fitting the flywheel and the drive gear on the crank. The seals are easily installed. The key is to have a socket head which matches the outside diameter of the seal so the seal can be driven home....just like the roller bearings. Just keep everything straight and resist the urge to apply too much force.

Yesterday I discovered that the Electrex World electronic ignition did not quite fit. Note the picture above. The tang on the Yamaha case just interferes enough with Electrex World backing plate that the mounting screw will not engage. This is not an impossible problem. I will just mount a grinding wheel on my Dremel tool and grind the tang (on the engine case) back a couple of millimeters and everything will be fine.

The Electrex World unit appears to be beautifully made but why did they design the backing plate to be so impossibly close? Really no good reason

Monday, June 2, 2014

Time to button things up....

Before I get back into this project I need to make an announcement....Do whatever you have to do to see the Moto GP race from Mugello. (June 1, 2014) It is as good as racing gets. If you haven't seen it, get a torrent...or see it at your friends house that has a DVR, or get a Moto GP video whatever is necessary. You will not be disappointed!

Back to business. I finally resolved the whole dowel thing. I was misreading the Haynes Manual. In fact there is only one dowel with seals around the circumference and it goes in the rear upper engine mount where it serves to keep the engine mounting bolt centralized (I think...). At any rate, we are ready to go. And if you need one of those dowels, I am the guy to see. I just ordered two more off of eBay. Stupid hurts....and it is expensive!

Above are the two engine cases ready to be joined. Since Yamaha does not sell Yamaha Bond anymore I had to search around and this product (ThreeBond) was widely recommended. In the above picture, both case halves have been given a generous schmear.

The cases went together incredibly easily. Just a little gentle tapping with a rubber mallet got it done. Probably less than three minutes to join the halves. I was initially worried that the ThreeBond would harden or get displaced as I fought the cases together. That just was not the case.

Next came the stainless socket head screws. Sorry to say the supplier elected not to include the longest screw. So there is one of the original Phillips Head screws installed. Can you see it? I can, and it pisses me off. I am going to get a replacement as soon as possible.

Torquing the screws was easy because of the socket heads. I have no idea how a Phillips Head could be accurately torqued. By the way, all the screws got their own little stainless washer. When I took it apart, there were no washers.

Lastly, I cleaned off the excess ThreeBond and checked the shafts. All three shafts are turning freely and easily in their new bearings. Smooth as snot some would say. And, the transmission is happily in neutral, right where I put it.

Next up the magneto, clutch, gearshift assembly, flywheel, seals, etc....Then I need to go back to the TY Trials website and review the order in which all of these shafts and gears are tightened.

As a reward, I am going to treat myself to a long ride on the beach with my TLR....see you in a couple of days.

Wednesday, May 28, 2014

Stop all engines...

Earlier today I began to assemble the crankcase. It went together pretty smoothly up to this point. I managed to get the gears and the selectors installed despite being handicapped by having only two hands and ten fingers. This really is a project for an octopus. I remember reading once that this could be more easily done if the gears and the selector mechanism were tied together with some light string before being assembled...then you would just remove the string once you had everything installed on the receiving crankcase half. May be next time.

The problem arose when I went to install the dowel and o-rings to the engine mounting points. When I re-read the instructions in my Hayes Manual I realized for the first time that the term "dowel" was plural. You are supposed to have two of the little buggers. I only had one. The last guy to get into this engine had apparently mis-placed one of them and simply put the engine together with only one in place. This was not a complete surprise to me. When I took the engine apart and while I was taking the rest of the bike apart I noticed that there were almost no washers anywhere on the machine. This TY has led a hard life. 

Next I need to find a source for a couple of dowels. First I will try eBay just because it is quicker, but if there is nothing there, I'll be back at TY Trials. It seems silly to have to ship a couple of little tiny pieces from England to Mexico, but if that is the only choice I will do it. 

So for now, I am back to cosmetics until these pieces arrive. Stay tuned.

Who doesn't like new gaskets???

The big event yesterday was the arrival of some new gaskets (above). Despite ordering two sets of gaskets from two different sources, neither source sent me the gasket for the crankcase cover which goes over and encloses the clutch/kick starter assembly.

Also arriving were some painting supplies. Both of my touch-up guns which were last used about 16 years ago had died in the interim. Both guns fired off thick globs of paint and a review of the instructions included with the guns told me to remove and clean a piece which was not removable.  Not a big deal. They only cost $29.00 twenty years ago, and they cost about the same now. So, now I have a new one. 

Yesterday afternoon I installed all of the new bearings. It took some force and some heat and some refrigeration, but they all went in without any particular drama. One of the things that amazed me was the condition of the bearings and seals that I removed. If I had just cleaned them up they would have been indistinguishable from the new pieces. In fact I had to take some care that I didn't mix them up on the bench. The new ones do feel a little tighter, and the seals do feel a little bit more supple, but I am not entirely sure that they all needed replacement. Next...the cases will go together with all the important bits inside....I hope.