pschrauber

If I would be in your situation I would opt which suits best my riding style and which I know best in technical matter. If I ask the Fantic guys here in Germany they all state that there is no big problem getting parts, likewise Yamahe, Montesa, Bultaco and even OSSA last but not least even SWM or early Betas. As long as you don't seriously want to ride a Merlin or a Trans Ama the part situation is not helpless if part of the game is a little research here and there. Good luck in the election.

Got the brake unit back, that cure worked very well. The chalk contact pattern that was visible is now milled away. (The brake was centered to the axle while milling). It works perfect now. Thanks again.

Good idea, I have phoned with my lokal KTM shop here in northern Germany they will mount the complete brake (backing plate with assembled shoes) on a mill and then align the brake linings. I send them the brake unit by post wednesday. When I pick the brake up on saturday it will cost me a pound coffee they said. @Nigal Dabster: I still wonder why I should be getting red? Olives and peas does this fit / taste together? Which dish recipe do you mean?

Oh are we a little bit the prince on the pea this evening? (*) (after Hans Christian Andersen, some Danish world literature might fit here too). Please keep in memory, to bring the vegetables here to the "table" was not my idea.

OK, will get a rough file rasp, when I understood right I should better use a rod file then a flat one? The 175cc Bultaco had alloy ones, this bike have steel ones front and back! These where the original ones that came with this bike, they are really loong, but my model has been made for Italy in 08/1981? "tracing paper thats novel" sounds very british sadly I'am not so sure what it means. Oh yes please, I'am very interested in any modification that helps, (I mounted a slightly heavier spring to the rear brake shoes, so the brake action might be a little bit more clearly (I hope)).

Thanks for the good advice. Unfortunatly I don't have any engineers blue, only tracing paper and chalk. In my destitution I therefore chose chalk, which worked somehow. It looks like the lining of the one brake shoe is completly too thick, (beside one triangular edge, which must be a production failure). The other side touches the hubs "only" in one quarter of the "shoe area". Milling down so much, without any special equipment, mmmh ... sounds like a job where you have to use a lot of "elbow grease" without knowing if it ever will turn out right. I will sleep about it, we'll see what the next day will bring. BTW.: - My hubs are not re-lined, they are still ok. - I believe I have the right brake arms, they are very long and out of steel. Yes, theese brakes are not so good, they are crap in water, the chrome plating inside the of the hubs have the tendency to chip of. The action is bad, the front brake arm looks out like a figurehead of a sailing ship. the rear brake "feeling" is bad because of the long cable. ... It's a Bultaco ..., I have a 1979 TY too, switching the bikes is a complete different experience when it comes to braking.

I just replaced the brake shoes to my Bultaco, got replacement ones and installed them. when I mount them without axle all seems OK, there is some space so they should run free. BUT when mounting the axle they don't fit the pads slide very strong. Some options: - mill away a mm or so on each side of the supports to the cam, (they look thicker) - mill away the sharp edges at the beginning and the end of the linings? - get another pair of shoes that fit - ... Any better or other suggestions how to align the lining so they fit again. It's "difficult" to see where the problem is. By the way the axle is not bend!

The desired surface should be absolutely clean and free of grease. To clean the "pores" of the surface, I use pure polish for paint or plastic, without any wax components! Then I wipe off the surface shortly with brake cleaner or acetone, just to get rid of any grease and fingerprints. Best way to avoid finger prints is to use gloves! Before you mout the Sticker, pull the sticker off the backing paper and spray "relaxed" water to the adhesive surface and also to surface that will be later covered. To "relax" the water use a splash of detergent. Then you can apply the sticker surface without any force, now you can move the sticker / decal back and forth until it is at the right point. Then you eliminate the water away with a squeegee, this in systematic approach, (the procedure depends on the shape of the label and the surface and is sadly too complicated to explain, perhaps there exists a good How to ... video on Youtube). Afterwards warm up the ground with an ordinary hair dryer and if there might show up small air bubbles in the push them away to the shortest way towards the edge, use the squeegee to do so. (If the decal is warmed up and the aadhesive still fresh this works very fine. Then wait at least one day befor you ride or wash, ... your bike. Done and ready for riding.

Any discussion of pre-mix ratios opens the pandora box, anywhere and anytime. I do not know why, let's take it as a statement. here I can only state my personal opinion. @ BultacoSteve You are from Canada than you might know "vintage speedy", or in his full name Helmut Clasen, (He is a member of the Canadian "Motorcycle Hall of Fame" lists so I assume you might know him ?). He runs also Optimol at a ratio of 1:100 in his bikes, (That he is still racing, ....). His statement in the German Offroad Forum from 2009 where they discussed if there is any oil as good as the old MAICO racing two stroke oil that could be used in a ratio of 1:100: [url="http://www.offroadforen.de/vb/showthread.php?72676-Maico-Renn

Just to note Bultaco started in 1978 with their own 1:100 two stroke oil! So this is nothing tricky new it is vintage old. Here an articel about Bultaco motorcycles from 2002 from Oldtimer classic about the first use of 1:100 ratio two stroke oil for the Sherpa: The Bultaco Sherpa was my first "bigger" Trialsbike in 1980/81,^^ So I do remember very well these times and what we used then. In this technical "matter" it's kind of strange that there has been no development in the ratio case of pre mix gas, I would rather state we have gone backwards now ???

When Bultaco was still in business, there was a special synthetic two stroke oil under the brand name Bultaco available, it was made specially for Bultaco. With this oil you could run the engine for trial purpose with 1:100. The manufactor of this oil was OPTIMOL in Munic, they made 200ml bottles with a scale on the side for every 5l gasoline. Sadly Optimol has been bought by some US guys already decades ago, they still manufacture the oil but don't sell it here, the manufactors name: Interlube International Optimol 2-4 in the USA The Opti oil has some special treatments compared to other two stroke oils: Technical ... With a good sysnthetic two stroke oil from Castrol, Motul(France) or MOTOREX (Switzerland) and premium gas something between 1:60 up to 1:75 will also work, (I use 1:75 now, sadly my last bottles of Bultaco two stroke oil had been used with my Beta TR34 in 1987). Benefit of less oil, less carbon, less clogging up the exhaust system.

The frame number should start with two letters then a hyphen then comes 3 digits with the model number. like your mentioned 198 after that the serial number of that number, a or b models are marked by a second hyphen then comes the letter. Number as follows: AA-MMMXXXX-S A: letters M: model number X: serial number S: A or B model, (if none of this forget the hyphen and the S) Here as an example for the serial nuber of an 199b model:

Mmmh ... turn the screw in until it locks, (for turning in clockwise direction, or rechts herum in German or turning right in Englisch). Than turn the screw out 1 and a half turn against clockwise direction, or links herum in German or turning to the left in Englisch) This is the standard position for the pilot screw, (NOT the idle screw!,)the engine might run but not best, no you can finetune the by turning in quarter revolutions. If you turn to the right, close the screw, or clockwise the mixture will be leaner. If you turn to the left, open the screw, or counter clockwise, the mixture will be richer.

congratulations, a very nice bike, needs some work, but thats part of the game and is fun too. I had the same problem like you when I found my Bultaco the upper stanchions where bend and the chrome was scratched. My forks after disassembling: I looked for a second fork and found one in France which was complete and came together with the fork clamps, the price was OK. Well ... the stanchions had some rust marks and where worn out, (the lower fork legs that work as guide for the stanchions too. Here the second fork from France: After a deep breathe I decided to attack my wallet and gave both stanchions away to a company here in Germany that do real hardchrome work for machinery parts. To rework stanchions is not their daily business but there fabrication tolerances are extremly high and they can also straighten them. Here their website and normal products: Wissing Hardchrome The costs is around 110

There is so little participation recorded so far?, It's a bit strange. Just guessing : - maybe the bike is really good, no real issues, (beside the one posted befor)? - maybe only some OSSA users do have an Trials Central account? - maybe there where only a couple sold, like three or so? Maybe there are more positive effects ?

As already mentioned: I do not know how the rocker is mounted to the rockeraxle of your bike - I have no experience with Frontera or Pursang models, there where to different construction, (as I know): - A: one with bronze/brass bearings, (like model 199a and 199b) - B: one with rubber bearings, (like model 221) A: When you have bronze/brass bearings there should be inner bushings made out of steel, these are wider and should fill the gaps, soem space you need for assambling as already mentioned by John Collins. By the way the O-ring on the each of the outerside between the bronze/brass bearings is also a little bit "responsible" for the gap. B: When you have rubber inlays as "bearings", (some older Bultaco bikes, at least some Sherpa's like mine model 221), then there should be a small gap between 1-2mm on each side, for mounting the engine mount and the rocker. this gaps will be closed when thigtening the bolts of the rocker axle. I would say if there is onle litttle play around 1 - 3 mm it is OK. There are no extra spacers to mount as I know.

As you already have the rim, just to note the punches and the direction of the holes of your rim have to fit the hub and the way the spokes are mounted? (Just my two cent opinion). To the dimension, the tire is a 4.00'' wide, your other rim "only" 2.15'' the original 1.85'' so where is the problem.

You can look up here, they have sprockets front and rear, maybe they manufacture a special one on your request, but this will cost some money! Talon

No experience, I did change my rims, but took the standard width. I know it is not so easy to get Acront rims nowadays but it's still possible, even the original red and yellow label one's. If you need the ressource PM. My question to you is why do you want to mount a wider rim?

As I know the rear engine support is made out of steel, (it's steel on my model 221 and on my model 199b). There should be the Bultaco logo stamped on the outer side which faces to the tire, then it is original, (once again at least on the 221 and 199b model which I have).

Yep, 11 teeths front and 39 teeths back suits best.

Go for this gearing, just perfect IMHO and the standard for this bike and model.

Mmmh, If you have installed the bearings right there should not come out any oil, Now there is only guessing left: 1. The axis of the front sprocket spindle contains the shaft of the gear box and the clutch pressure rod / pin, like these russian puppets. May be you have something installed the wrong way from the inside? 2, Maybe you have just filled in too much gear oil? Where does the oil come out: -a between the sprocket shaft and the oils seal -b between the sprocket shaft and the inner shaft -c from the hole of the clutch rod/pin? Maybe this helps?

The speedo drive is mounted to the rear! Try Bultaco UK, they should have the parts to mount the original speedo. You can mount the speedo at the top of the fork or at the left side to the front engine mount.