chappo

Finished the 198a. Now going to give my competition 198a a bit of TLC.

Thank you everyone who replied, great information as usual.

Hi guys, Bought a Bultaco 198a in a box a while ago and I'm I the process of rebuilding her. I found that the rear shocks were a pair of Girlings, in Bultaco blue. I've had them resprayed when everything else was being done. The question is, were these original shocks to Bultaco sherpas around the late 70's early 80's. From memory I seem to recall these shocks due to the distinctive alloy spacer / adjuster rings but cannot be sure. I've checked a lot of old images from Bultaco but don't seem to be able to find any images of a Sherpa with these fitted ..........anybody recall them????

Hi Toneh, Just a bit of enthusiasm for you. I had one in your condition a couple of years ago and rebuilt her. Some photos attached. ( I do have more but didn't want to bore the readers ).

Bondy & Noel, The winged bashplate was on when I bought it, I've checked it and it doesn't have any names or markings on it, may be a home manufacture. Either way it protects everything it needs to without looking nasty. The only downside is that you have to drop it each time you need access to a casing. Also put a new Mikuni carb on her yesterday after rejetting and wasting about £40 on new jets etc for the old Mk 11 Amal and getting nowhere. It's made a huge difference to my bike, runs a lot cleaner and sharper, whilst I accept all bikes are different, wear rates etc, it's cured my fuelling issues. Next time I take the bashplate off ill photograph it for all interested parties and put some measurements with it.

Thanks Bondy, Just put it all back together and wow what a better feeling, I know the purists will probably be having kittens but it feels so much more comfortable and balanced............... I like them.

Finally got round to replacing the foot pegs on my 198a. Cut the originals off leaving the outline of originals so the welder could get a measurement, they have actually gone back 5mm and down 10mm, not much of a change. Just primed the metal hangers and surrounding exposed frame, ready for spraying tomorrow.

Hi guys, Did my first event a few weeks ago on the 198 and I'm not sure how the front brake should be, or made better with the appropriate advice............... Bearing in mind I ride a modern bike as well with a front disc brake, but the Sherpa has had new grooved quality shoes fitted , the brake drum has 90 percent of its lining still on and the cable is a V make cable although old has been oiled. The cam has been cleaned and greased but the cable on brake activation seems to come back to the bars no matter how I adjust it, I accept prior to that braking does commence. Am I expecting to much ??? Back in the day they seemed better. Any advice?????

I bought one....... Bit of nostalgia at 56, remember riding one in 1981 and although I ride a modern bike now I always fancied revisiting my past, when I wasn't half bad, now I'm pretty average. Anyway a problem with my modern bike made me take out the Sherpa to a local event last week. What a good time I had on her, a real blast from the past with memories coming flooding back. My mate who I ride with said I rode it better than my 4rt !!!!! She has electronic ignition and ran really well seeing I hadn't ridden her before. Just by the end of the trial she was sounding noisey at the top end and running hot, to be investigated. What a great experience, don't think I touched the clutch lever in any of the section ?????? Anybody recognise the winged bashplate, is a homemade adaption or were they manufactured to that design, looks a good mod until you want to remove a casing.

Yes , Baldilocks, it was on a greasy grass camber, I appreciate that something has to give but all that damage, the bike only skidded about 7 feet , t.hat damage is excessive for that fall. A cartwheel down a rock banking I'd have but ,this was minor, I've ridden an enduro bike that's had more offs than that without any problems. A simple snap of the shaft, but look at all those minor stress fractures on the third image !!!!!!!!

Thanks for the advice I got in relation to my previous post on this matter, please find attached images of my selector shaft when it was removed . I can't believe that this much damage / stress fractures could have occurred after such a minor 25 mph off. Has anyone else had trouble with a selector shaft where this much damage has occurred . Bear in mind this 4RT is 8 months old and has been ridden sympathetically and maintained meticulously by a 56 year old rider.

Hi guys, yes you were right about the selector shaft, but it wasn't bent it snapped off. I'm really surprised at this as the "off ", that caused the damage was a fourth gear slip on a greasy camber at 25mph , didn't even part company with the bike, dipped the clutch when we stopped stood it up and set off after a quick visual inspection. Just glad I decided to stop the engine when it failed to select a gear looking at all those small pieces waiting to break off and cause untold damage in bearings etc. Parts, the shaft, gaskets and oil came to £67, which I was pleasantly surprised at being a Honda, thought it'd have a 1 in front of it. Anyway back running again and thanks for the advice guys.

Help guys, Has anyone had this problem. I was at a trial on Monday and had an off on a moorland section whilst in 4th gear, the bike fell on its left side and I didn't part company with the bike and was able to dip the clutch, picked it up and set off. The gear selection at that point became a little stiff but just thought I'd bent the lever in a little bit and muck from the off. Did another section in second gear, just tried to change up as I set off to the next group and the gear shaft moved up and down but it wouldn't select a gear. There was nothing there apart from the spring resistance. The engine was running, the clutch action was fine, no strange noises, but decided to err on the side of caution and shut the engine off in case there was anything floating around. The bike is a 2015 model and 9 months old with about 20 events under its belt and regular maintenance, I bought it new. Yes I know it has a very comprehensive manual but I've lent it to a friend so unable to consult it for a week. Someone mentioned that there's a pin on some other makes of Spanish trials bikes selectors that are built in to shear off rather than cause damage to the selector?? Many thanks guys.

Hi guys, I have a 198a that I recently purchased to try some twinshock events. It has a lovely alloy tank that would be criminal to dent when I drop her. Thinking about buying a plastic one from that well known uk supplier but everyone says the decals will bubble with the ethanol etc. Is there no way to line these tanks , there seems to be an abundance of products about but would they work I'm sure someone's tried them. All advice welcome before I put my hand in my pocket. I'll try and put some photos on. Dave.

'STOP PRESS' No Sonic cleaning required. The jets came before the cleaning was sheduled to be done , so I popped in all the new jets ( full set ), that Amal UK sent me. By the way fabulous service, spoke to a very helpful guy in the Technical Section, agreed the jet sizes from what I had to what they say should be in which were identical, ordered them and there the next day. Couldn't wait so cleaned the carb again, put the jets in and she fired up straight away. Running like a dream. I can honestly say that every jet and orifice was cleaned with carb cleaner to within an inch of its life so it wasn't an obstruction. Each jet examined under a magnifying glass and clear, slightly oval not round but clean. The only thing I can see that may have been worn was the needle and main jet through wear. The only other possibility was that the original carb, which I didn't notice initially until the spares arrived was that the overflow pipe was a continuos loop with no outlet. The spares kit came with two small pipes for each overflow but not connected. Could it have been it caused a vacuum and lack of fuel ??????? Someone with more knowledge and ability could probably answer that. Just thought I'd post my findings, as many people ask advice, get it and don't bother to to give everyone the answer when they solve the problem. Thanks guys, terrific site.

Thanks Bondy, Seen your Sherpas on here, is that what you have on yours, the Mikuni replacements? Jets have arrived today, just want to try and get it ready for a first outing this Saturday. After that I'll look at the Mikuni options.

Thanks Sherpa 325. Mine starts a treat runs smoothly on choke, but not that fast, you then turn the choke off and it dies. New needle and full set of jets on order. Thank you.

Thanks gentlemen, That gap info is great, not taken the flywheel cover off yet so not sure of the manufacturer. Larry, yes my mistake it is an Amal 2600 series 2 concentric. Ordered a new float and associated jets, the jets that Amal have on their records as being correct for the bike are the ones that are in. Going to have it sonically cleaned then fit the new jets and go from there. Will update with progress later in the week. Regards, Dave.

Thanks , with it being stood for so long it may be the crank seals that have failed, or at least the flywheel one as it's not smoking. I'll start looking for an air leak. Any views on the plug gap for electronic ignition, or is it the same as standard?

Hi guys, Just bought a 1979/80 198 A 250, it has electronic ignition. I've bought a new spark plug which I've been advised needs a gap of 0.4mm, but when I ordered it I didn't say it had electronic ignition. Is there a different gap setting for each. Also the bike runs and starts well on choke but dies when the choke is turned off. I've had the carb apart and found 150 main jet. 20 pilot jet. 3 slide. 2b1 needle 106 main jet. I've had carb cleaner through each and every orifice, because I thought it would have been a blocked pilot jet. The previous owner has owned it for years but hasn't really used it for a few years. I've drained and flushed the tank and got new fuel mix at 50:1 with synthetic oil. But it runs fine on choke and then dies. Am I missing something obvious ?????? Many thanks.

Thanks Woody. What about the mix ratio. I have some normal GRO trial 2 stroke oil from a previous bike so I'll use that up, after draining the 747 mix. I agree looking at the spec sheet of the 747, it is overkill.

Hi guys, Just taken delivery of a Bultaco Sherpa 250, 1979 , I need to know the type and quantities of oil required in the gearbox, clutch, forks and what type of two stroke oil. The previous owner used the new Castrol 747 2stroke oil, at 50:1, is that right . Many thanks. Dave.

Thanks for that. I'll risk the investment and make my own my up and report back.

Thanks Oz Thumper.

Guys, I have a 2015 model with standard rear spring. I have read that there is an upgraded heavy duty spring for the heavier gentlemen, Iam 100 kilos or 16 stone, has anyone of similar frame changed to the heavier spring and is it worthwhile. Also has anyone had problems with the main rear mudguard decal beginning to peel/ lift at the lowest point , just on one side, it's only a small amount but it's only going to get worse. PS. It's washed by hand ,no power washers before someone asks!!