pschrauber

Don't check them too often, there is little wear on a "trials thumper" like the Bultaco. Once you did a rebuild and just ride it on weekends they will work for years if you don't have any breakdows caused by other reasons. To check the pistons rings there are two things to check: First the wear or toleance of the notches where the rings are mounted to the pistom. The gap between the noth of the piston and the bar of the ring should be a clearence of - around 0,05mm this is good / normal - around 0,10mm there is some wear still useable a limited time - around 0,15mm is the limit, then you have to replace. Then you can check the clearance of the joint of the rings. To check this you have to put them inside the cylinder, the ring has to sit 40mm below the upper cylinder edge, the ring has to sit absolutly parallel to the surface of the cylinder. Now you can measure the gap between the joints, the clearance of - around 0,20mm is OK/normal, - around 0,30mm there is some wear but sitll useable a limited time, - around 0,35mm or more then the ring has weared out and you have to replace. If only one of them shows exessive wear you should replace both rings. BTW: Be very carefully when deassamble and assembling the rings.

I have a colored wiring diagram I made myself to get the electric sorted, sadly it is in German, but I beleive it is easy enough to understand as the wires are drawn in color, here a scan of the drawing: # 8 is the resistor # 9 is the rear brake switch #10 is the rear light, Masse = earth/frame R

Hi Bondy, when you have got the pin of the spring fitted inside the hole of the kick starter shaft you turn the shaft completly to the left and then hook up the rear end of the spring to the thread rod. Then secure the rear end of the spring with a nut and the second secure nut made out of plate. At the end of assembly it should look lke this. (the arrows show where the front and rear end of the spring should be located): for your assembly!

Hello Bondy, so you are not pleased with the standard one, which looks like this: (I'am asking just to be sure that I understood you right) There is the thicker kick-start rubber of the later 199b model that you can mount to your kick starter, this one looks like this, the rubber is around 25mm in diameter: You will get this rubber from BultacoUK I believe, if they don't have it you can try here: Link

To the look of a bike, I think the eyes always goes with you while riding. An easy to fit "trick" part that does not cost much money are fork bearings from ariete, they work much better then the standard singel / twin oil bearings, have less friction and less initial break torque. They come with an extra dust lip too. They fit together with with the old round dustcover. For Betor and as twin lip bearing it's Ariete type DCY 35 X 47 X 10. You can place some oil seal greae between the lips this will keep them much longer smooth and thight, [url="http://www.yatego.com/ersatzteiltresen/p,4a20f837938a9,4a1ff2f5e381f8_9,gleitmittel-fett-f

Haven't we had this somwhere as a thread already? Here a copy of the repair and maintance manual: The sequence which nut or screw you have to mount is prescribed in this picture. The torque stepping to max torque is 3 Nm. Nut and screw #07 and #08 is up to 18 Nm torque, while the others get 15 Nm. Use some grease like "never-seeze" so the bolts and nuts turn smooth.

That's a nice bike, need some TLC I believe. I have seen two modified older Sherpa models that had some modifications on the todotrial and forums website, one is captured here: todotrial And the other one a Sherpa N here: To modify or not that's the question? As I understood you you don't want transform the bike completly just as far as it is later easy to get the bike back in it's original condition. That is a strategy I try to follow too, (with an earlier model). As Woody already posted it will not turn the bike to a complete winner but I think it's good for the personal self-affirmation of the builder and rider. I would do some changes to the suspensions, there are good conversion kits from magical for the fork and a lot of aftermarket shocks available. Maybe a switch to the OKO carb, as posted a couple of weeks ago this is a good improvement. (this OKO24? OKO24) Then probably the exhaust need's a rebuild because the unit'(s) are clogged with oily debris? The guy's at Secciomotos in Barcelona are very good in rebuilding and tuning for Bultaco's exhausts. Beside of this a good paint job, and small little improvements here that might be satisfying you too, like: - grooved brake pads, - lighter chain, - paint job, - ...

Yep, I do. Not that I like the full electrical equipment very much but I need this for getting the bike road registrated. First then I can get a classic / vintage bike rating and an insurance for the bike. The Bultaco uses 6V, the FEMSA or MOTOPLAT ignition and generator is "rudge" in the delivery of electrical power, (not continouos and in variable power depending of thr rpm), so you need something to get rid of the power peaks otherwise as you already mentioned the bike will eat bulbs frequently. The Bultaco Sherpa used and uses this resistor which is a very simple one. The resistor has to be mounted to the frame and connected to the rear light. Beware, when getting old and rusty this device will not work proper any more. BTW: The original switches and kill botton wich came with this trials bike where very simple and did not work "so good" either they failed often and break down very easy. Bultaco had some better switches and an electronic regulator too, but this electrical equipment was used for the street and enduro bikes. Some Sherpas where fitted with the better equipment when flashlight are required for getting the bike road registrated, like in Germany, Austria and Netherlands I believe, ...). This equipemt was taken from the Metrella (Bultaco streetbike models). The better original switch unit from the Metrella is: - Leonelli Art. Nr. 074 PA7 (complete switch unit with flash switch) Instead of the simple resistor the Metrella and the mentioned Sherpas got an regulator, the model that fits to the Sherpa is: - FACOMSA 6v - LIMIT - 45W, Volante Magnetico, Ref: 1300601 Both electrical parts work much better as the simple ones and are still contemporary. As a switch unit you can certainly take other units. To try a differnt regulator can be a problem for your generator/ignition or both or the different regulator. regulator and generator have to fit each other if not they can "destroy" each other. So I would be very carefully if someone offers you something completly different to your existing old original ignition/generator. There are replacement ignition/generator units available for them you can use a regulator that is recommended by the producer/seller. Hope this is helpful

I would first try BultacoUK: www.bultacouk.com If not there try Orlando Calonder in Switzerland: www.orlandocalondersa.com regards Patrik

Black is nice too! Yes you have to trm the kicker shaft about 1/4 backwards otherwise you won't have enough space for mounting the spring.

Yep that is right, if you put the sticker on and leave the gasoline inside the tank you will get bubbles under the decals. If you want them to stay get a tank made out of glasfiber or aluminium. The round bage sticks so good I personal don't think you will get a problem here.

Painting the cylinder head black, engine body is black too and leave cylinder blasted, Mmm ... well you can give it a try. The kickstart spring mounting you find here: # 5 and # 6

I have heard that name already in an other Forum, ADVRider, olds cool department, there are quite a lot Matadors in the US around, In ADVRider there where just two rebuilds completet, (user: blaine.hale user: tenorjazz). Looking over the pond from the Europeen view it looks like there are more Matadors around then Sherpas from this decade, (my personal view, motorcycle.jaxed.com search engine for US craiglists. I follow the statements of the previous posters + 1 for their opinion! Get a Sherpa, it will be more pleasent to ride in the "rough" or a TY (I know something different but less expensive in the US). The time, effort (and money) you will spend to do all these modifications will not be as noticeable in the outcome compared with a Sherpa.

Just cleaning the threads with air might be not enough, there can be still some debris left of the blasting. I had the same problem with my cylinder. First I tried to cleab them up using brake cleaner sprayed inside the thread holes and then soaked it up again with paper rags. It helped but there was still debris left. I then took some cotten wool wrapped it around a small stick soaked it in WD 40 and then srewed it inside, out again and this worked very good. Befor remounting the head I applied some grease on to the bolts and nuts then they went really smooth in.

These are good/interesting news. I'm looking forward to Your report. Patrik

When you blast parts you will befor doing so cover any threads with strong duct tape or fill threadhols with a rubber piece? I first would try to recut the thread befor installing a heli coil. If this does not help / work then first I would take a Heli-Coil.

I will do a fork swap to my 125TY too, got my hands to a complete front end of a TY250 from 86 I believe. There you have distance difference from at least 4mm between higher clamp to lower clamp (lower clamp is >/+ 4mm farther away) to the steering axle. But distance between the stanchions is wider so you need a new front wheel axle and bushings.

There was much interesting discussion about the OKO carb for the Bultaco. How about the Dellorto PHBH 28mm or 26mm, round slide type, there is some information here in the Bultaco departement, but I found no hints about jetting and how good or bad this carb work with the engine. It would be very interesting to read something about this carb too. At least here in Germany the DellOrto PHBH is much easier to get, (even jets) and the carb is much cheaper too.

The book is named: Observed Trials Editors: Bernie schreiber and Len Weed The book sometimes show up in EBay in the US, but it's getting more and more rare, there is another one which is also very fine from Len Weed and Lane Levitt: It's named: Motorcycle Trials Techniques and Training A couple of years older but also with very cool pic's and training stuff: Even more rare then Bernie's book.

Here is a 199A you find a summery and video on Zonatrial. The bike was shown in 2010,(the site is in Spanish).

I dont't know If I have expressed the use of the screwdriver right, here a scribble sketch that shows how to press down the other widings of the spring or press up the first for inserting the pin:

Hi bondy, OK, how I de- and remount the kickstart spring 02: First unscrew the securety nut made out of plate, Second unscrew the second nut that holds the spring. These are the nuts that are located right above the kickstart axle. Third I unhook the spring from the bolt using a self made spring puller which I have made out of an spoke. The commercial ones look like this: If you don't have a spring puller you can use a wire too, that you wrap around the spring end. The ends of the wire you can roll up on a wooden stick or metal bar so it's comfortable to pull. Now you can hang out the spring easy. Now the spring is loose and it is now easier to pull out the spring from the kick starter shaft*. To do so again you use the spring puller or the wire method mentioned above. If You have difficulties getting out the spring end, you can pull with the one hand and press* the other windings of the coil down, (with a screwdriver f.e.). Then you should get loose your old spring. The new spring just push it over the shaft the end wich is mountet to the pin to the upper right comes first over the kickstart shaft. To get the spring over the shaft you have to bend the front end upwards*. Now take a narrow pliers and pull* the front end of the spring back until you can insert the spring wire in the hole of the kickstart shaft. Again it can be nessecary tu push down the other windings of the spring to get more space, (with a big srewdriver for example). As a plier I use the Knipex key pliers, one of the best pliers you can get: Some of the springs are probably too long as already mentioned here, if so, (luckyly haven't happend for me), you can shorten the spring end a little bit but the front spring end should be nearly as long as the diameter of the shaft. After the front spring end is mounted in the kickstrat shaft hole, you now can strech the spring by hanging up the rear end on the pin using the spring puller or the wire. No secure the spring with the both nuts, ready. * you have to use some force but no jerky violence, than the spring will crack.

My two cent experience: Discoloring by gas vapors looks like this: Difference in effect is that you find these brown / yellow coloring not only on the surface but also inside the plastic. When plastic is discolored by UV bright plastic parts like white light grey, ...turns yellow (darker) and dark plastic parts turns brighter, but only on the surface and through the whole material. The next question is what kind of plastic is used and this question is really dificult to answer because it's mostly not recorded to the older plastic parts as nowaday. Even if you would no it's PE for example there exists at least 6 different PE plastics, only PE-HD for example is completly resistant against gas vapors the other PE plastics, like PE-LD, ... not. The fibreglass gas tank are all reproductions and are not street legal. The plastik tanks where approved by Bultaco trough the German T

Got mine from here spokes and nipples for Bultaco Calonder have them stock. He produces spokes and nipples, so you can get even get the nipples in alloy and the spokes in in stainless steel.