Bultaco

Hi Trialers, I'm upgrading my Sherpa m159 and one of the mods I want to do is to change the front mudguard along the lines of those carried out by a lot of the Spanish twinshock riders. any ideas on which brackets I could use would be a great help.

its got to be said that footpegs on a sherpa are not the best, especially compared to the ones on any mono can any one tell me are there moderen pegs that will go straight onto my 76 sherpa T model 159, or do i need to to get some one to weld new brackets on etc etc if there are not any you can get off the shelf i wonder if bultaco uk would think about developing some as this is a sensible upgrade which many people would benifit form?

Need new fork springs - current springs are do not know type (one is slightly longer, and have a valve spring squished in as well) They also top out at full extension. Being only 63kg (about 8 and a bit stone) should i go with the sherpa or the pursang springs. And also can anyone comment on non-leading axle pursang fork bottoms or fitting Alpina triple clamps please?

bought a bultaco 325 cc 1976 model few months ago as i have always had a modern bike always fancy a twinshock now i have one. I done a lot of thinking over the last few weeks as i beeen staring to renivate the bike about selling it on to get another gasgas/beta. As a keen watcher on ebay i see that some of the bultos are not making a lot of money when you can just jump on and trial the bike is it worth me doing the bike up or just selling it as parts. I have stripped the bike of paint both tank and frame ready to paint so the bike is just parts now so would be easy to sell on if i decide to sell on as parts. The bike has matching frame and engine numbers also road reg and…

Well I rode my first trial last week and really had fun and learned alot. If there was one thing I could ask for however is an improvement on the brakes on my 77 model 159. I was constantly mashing both the front brake and rear to get slow enough to make turns after a short steep drop off or down hill and had too much momentum on several occasions. I have new brake shoes on both ends and all the mechanicals are in good shape so I have to wonder if I am doing something wrong. I know the brakes are working against some pretty good flywheel effect in the engine but I would think they should be more effective. The chrome on the hubs is in good shape and not peeling so that i…

Hi, I am just wondering what material the M-80 frame is made from. Mine has no frame number and is very light although extremely hard.( could not stamp number on footrest mounting area but can pick up frame with little finger) some areas have been stripped to bare metal for several months and show no signs of even the slightest surface rust. I know later frames were chrome moly which is lighter but were there any after market or factory frames made around 1970-72 when the slimline was built? cheers, Myson

Hi All. Can anyone tell me if the steering stem thread size changed over the years. I have a stem with lowered alloy bottom yokes. I have a steel adjuster & top nut but they dont seem to fit although the threads all look fine. Could the thread pitch be mismatched? Any help appreciated, as always. Cheers. Hoodie.

Hi, I am about to put engine back together and was wondering, are the two alloy spacer washers needed between piston and con rod and if so, what do they do? Cheers

Good Day Gentlemen, After reading the post in regards to the pre-65 Model 10, I thought I'd share this with you all. I found this early Bultaco local to me this morning. It looks like a Sherpa N. It has all original hardware and fittings except for the throttle, fenders and silencer. The front fender is actually a piece of all that is left of the original (I can tell by the fibreglass type) but reversed and a rubber flap added. What I find really interesting is that the frame serial number stamped under the seat behind the tank and is a very early Sherpa S frame - B-300087. That is a low number frame, has to be 1961ish. It seems to have all Sherpa N components exc…

Hi, Does anyone know if any series of the model 10 came out standard with a twin spark plug head? Thats 2 plugs in the head, one for spare not twin spark. Thanks,,

Hi My target was to bring my Sherpa back to original Kit campeon spec. To this end i have fitted a new middle box and a new triangular back box (both supplied by Butaco UK). When the back box is fitted it kills all low speed response and it feels like engine gets bogged down until it about 1/8 throttle, also it does not want to start. Middle box outlet internal dia is 22mm dia and back box inlet and outlet bores are app 19.5mm dia, would a reduction of 3mm cause these problems? Remove the back box and all is fine, a bit loud (96 decibels) but it really works well, fires second or third kick and runs sweetly. I do not want to be refused a start because the bike is a …

Hi all. Been collecting parts for my M92 project. I thought I had got a suitable rear wheel and brake plate, but now that I've checked I've got mismatched parts. The hub came from an m92, apparently, but it has bearing holders at 41.8mm ( must be for 42mm od bearing) and the bearing id seems to be 15mm. I have a brake plate that takes a 17mm spindle and I have a 17mm spindle that is about 260mm total length, with the 17mm section for 220mm of the length. The swinging arm is from an m92 frame and it has spindle slots with a height of about 17mm. If I measure it from the outside of one spidndle slot to the other it comes to about 195mm. So it looks like the frame needs a s…

I noticed that the Yrjo Vesterinen 340 'works' Bultaco, as advertised on eBay recently, sold for a whopping 8750 squidlettes (at least I think that's what it went for - I was too shocked to really concentrate on the bidding). Is it just me or does anyone else think this was a tad over the top? Maybe I'm just getting old (er, what's with the 'maybe'?).

Having sorted carburation and airfilter out, my bike developed a miss fire at the end of the last session. Sure it's ignition not had chance to have a look (bike's at work will get cover off on Monday) though remember seeing it had a femsa coil. What options are they for upgrading? seen the 'eletrexworld' kits and know other companies sell other versions, what have most of you converted to?. Or should I sort what I've got, check wiring, condenser etc? I use to race two strokes and had lots of trouble till I converted to Motoplat/PVL type, then just set the timing and forgot about it Also what's the timing setting for my model either in MM or Thous BTD? Thanks Tony

I have just finished rebuilding my 1976 325 Sherpa after many years of storage. Way back I converted it to a Mikuni carb as was the fashion years ago but now am going back to the Bing unit based on the comments I have read on other posted topics. The bike was not run for long with the Bing and the slide is not loose in the body so I think it is in reasonable condition. I have it running and it idles nicely but when opening the throttle from idle the power comes in quicker than I would like, I would expect it to be a smoother transition as the throttle is opened. The air screw is one turn out, the needle is in the middle position, and the timing is between 2.4 and 2.6mm B…

Hi, has anybody any tips on replacing the kick start return spring? I can't manage to get the new spring on the shaft.....is there an easy way of achieving this. Thanks, Paul, Sherpa T Model 124.

Saw this one linked from Todotrial yesterday. A few interesting mods and still looks like a Sherpa. Link Then select "Reportaje Sherpa " Seems like he's possibly using Alpina Yokes for less to zero offset and no tiller steering. Interesting exhaust setup. Obviously ridden by a capable rider though. Wayne....

Does anybody have any tips on freeing the crankshaft clutch sprocket and clutch drum nuts? I have the clutch holding tool but cannot free the crankshaft or clutch hub nuts with the engine on the bench (I dont have an engine stand). Should I (1) replace the cylinder, piston & head and lock the piston with a locking tool or, (2) replace the bottom half of the engine in the frame for greater leverage (3) do both. Without locking up the engine there is tendancy for the clutch holding tool to come to rest againt the gear selector shaft, which I feel needs to be avoided as I may risk damaging or breaking the shaft. My inclination is to replace cylinder, piston and head, put…

I have a set of shocks from a 1971 Alpina. They are red with chrome springs but I do not see any markings on them so am not sure they are Betors. (I could post a picture.) Are these rebuildable? Can I get a manual or procedure somewhere? I saw seals for sale on a web site but that is it. Thanks, Dan

I am going to attempt the rebuilding of both wheels on my 199A with relined hubs and new stainless spokes. Can anyone help me with measurements for the offset to the rear wheel? I thought i had measured accurately but now not so sure.