Bultaco

I got this tank with my 198A that I am restoring. I believe it is Fibre Glass [Not Good] and has a push fit fuel cap I believe it could be a period Sammy Miller item?

Hi all just had the ebay itchy fingers and brought a 1976 sherpa 125 rolling chassis, I'm wondering if the frame is compatible with the bigger 250/350 engine's or is built especially for a 125 motor. I know the wheels are 1inch smaller than the 350 etc but that's about all the information I can find on frame dimensions. I have two potential motors to fit in the roller, a yamaha 125 aircooled 4t the type that comes in the tyf or a pit bike engine. I'd like to fit the yamaha engine but there will be a fair bit of fabrication as it's probably a little taller than a 125 air cooled 2t, but if I come across an original bultaco engine of a bigger cc I might go down that road che…

Hi All, Just aquired a Bultaco 198-A I think? to restore. I was told by the seller that the bike has been in a shed for 30 years [And it looks like it]. I am after confimration of which model I have got and a few other questions. The frame Number is RB 198 03580-A Engine number is RM 198 03580-A There are no bottom frame tubes but a factory looking alloy bash plate fitted. Also the rear frame tube is missing and looks as if it is an original alteration. It looks like the 199A Bultaco on the In motion Bike ID page. I will be looking for a Rear Wheel and Brake Plate as there was an unknown wheel fitted very badly in the bike. I wil…

Hi, I need to buy a new swinging arm bush kit for my bultaco 159. Im looking for a bit if advice, is it better to get the Bush kit from inmotion or is there a better option out there ie roller bearings?

Does anybody know if the exhaust mid sections differ between 250 and 350 on m158 onwards.

Hi all. Piston sleeve. For a model 151 are they still available? Any help much appreciated Greg

There has been some discussion recently about SM Bultaco Hi-Boy frames, the attached link clearly shows the detail. Bultaco Sammy Miller highboy frame | eBay

I recently bought a bultaco alpina 350cc from bord na mona and it turns out the bikes numbers are different the frame is a 187 and the engine is a 138 the guy we bought it off of said it was like that when he got it in 1976 when he bought it off of harry lindsay in dublin so does anyone know how this happened or was it from factory

Hey I have a bultaco motor and im unable to figure out what model it is the numbers on motor are M-8901424 cant figure it out would love to hear what you guys think. :D cheers

I guess everyone has their own lockdown projects on the go at the moment. Mine is using up accumulated parts to put a Sherpa together using a late engine in a slimline (91B) frame. I am quite keen to get the bike relatively finished so that I can move onto other things, so far so good except I had some 35mm triple clamps that I thought would be suitable as they had quite a bit of offset but it would seem they have too much. As it stands with the rear shocks measured at 355mm (temporary fitment only to hold the bike together) the wheelbase measures 1335mm (52.5”). Standard is 1315mm (51.7”) on 340mm shocks I believe. Not sure I will be able to get this back by dropping the…

Hi, I'm Scott from the UK, I have just recently signed up on here, I am in the process of restoring a 1976 bultaco 159, I'm wondering if anyone would know the steering bearing number, this is the upgraded taper bearing and race? id like the number to I can source one from my local bearing shop.

Hi, I'm just wondering if people alter the foot peg position on a bultaco 159, I've read before on other old trials bikes that people alter them so they are lower and further back. What's everyone's thoughts just before I send the frame away to get blasted and painted?

Merry Christmas! Well the Sherpa is finally back together and after a short run up the road in a hailstorm all seems to be working OK. However, my initial difficulty in kickstarting the bike before I stripped her down remains. Surely it can’t be right that the kickstart (which is already high for my short legs) hits the frame (so much for new powder coating!) then the brake pedal and obviously the footpeg is also in the way and catches your heal even if you hitch it up? Is there a solution I.e. an alternative base pivoting or cranked lever that has some additional clearance? I’m used to kickstarting my T140V Bonneville but that doesn’t hit anything on the way do…

Hi Guys, I need to get my Sherpa 199A wheels respoked. Anybody any ideas of a wheel builder near Glasgow or central Scotland?. Thanks

Hello, I’m hoping that some of the depth of knowledge on here in the trials world might branch out a wee bit! I am trying to find a clutch basket for a Mk7 Pursang, 360cc, model 121. I can find examples of new and used baskets for other marks but not for the Mk7. I understand that there are subtle differences between the models but I do not have knowledge of what these are. I am hoping that someone might be able to tell me that a basket for a Mk6 might do the job for example? I’m also unaware of whether there are differences between the 250 and 360. the old basket removed from my Mk7 is a 38 tooth duplex with an overall outside diameter of the basket of 118mm an…

I've just put the clutch back together after fitting new main seals, etc. When setting the tension on the clutch springs, how far do I tighten the nuts? I have assumed the tops of the pins and nuts are level, but is this about right?

For a French chum, could anybody please tell me if there is any particular material you need to use when re linging Bultaco brake hubs where the chrome has worn . Thanks

Sorry, so many questions... Could anyone from experience please confirm the correct timing for a 198a? The Bultaco UK (InMotion) Workshop Manual in the 'Model Specification Chart' states 3-3.25mm for the T250 - which is the same as the T125. But InMotion have just quoted 2.5-2.77mm - which is the same as quoted in the Workshop Manual for the T350. This would make sense to me as the T250 stroke is the same as the T350 at 60mm; whereas the 125 is shorter at 51.5mm. Looks like it could be a misprint in what is a complicated spec. table that covers something like 20 different models? Thanks yet again!

Can anyone supply original spec figures for wheel rim offset for my 198A - not in the manuals as far as I can see? I loosely built up the rear wheel yesterday and couldn't get near the offset I'd measured before I stripped them down, but if the rest of the bike is anything to go by nothing has been very stock! Wheels are Akront 21" 1.6 - 36T-581 and WM2-1.85" 36-TR-11-78, hubs concentric, new spokes from InMotion and are the same lengths as originals etc. so all stock as far as I can make out. It could be my lacing at this was a first attempt, but I (thought) I'd done it OK!

Hi, the rebuild of my Sherpa 198A is progressing 'well' but I have a question on what is the expected / acceptable swing arm free-play and 'stiffness'. I have replaced the nylon/alloy swing arm bearings and spindle with new items, but find that with the newly powder coated frame and new replacement rear engine mount (all from In Motion) its all a very tight fit - requiring the rubber mallet persuader to fit! The result is that although nice and smooth, the swing arm does not freely move under its own weight (a rough measure I've used on road bikes with needle bearings) but requires some force (approximately a 1kg weight placed on swing arm) to move even without the swing …