sherpa325

Back in the 70's when these bikes came out it was impossible here in Australia anyway to buy different weight/viscosity fork oils, so everyone that I knew used ATF - 180cc. If the fork topped out [clunked when doing a wheelie] just add another 10cc until it stopped. I have tried the newer fork oils in my Bultacos and I feel they are too light for forks built in that period, so I just continue to use 180cc ATF with no problems. I am very fussy about the setup of my bikes and for example I use 2.5 weight in my 300 Gas Gas as the current forks are sensitive to the modern fork oils. Cheers Greg

I was pretty sure the Montesa one fitted , off the 348/349 [30mm]

I am pretty sure all Dellortos are a fuel screw not an air screw, winding in leans it and winding out richens, the opposite of a Keihin or Mikuni. There are actually three Dellorto trials carbies- PHBH 26mm or 28mm[large body]- PHBL 26mm largest [small body] and the VHST [D or flatslide] and its the one that's difficult to keep in tune. The PHBL & PHBH are quite good carbies and require very little adjustment once set up correctly, most people changing the pilot jet to get the feel they like. Cheers Greg

Definitely standard on some models, often thought it may have been for the enduro/trail bike larger seat?

The problem you have is that the shaft is parallel and not tapered, so the flywheel is driven by the key not a taper. The only way I could see around this is obviously a new key and if this is a sloppy fit in the shaft then you really are left with trying to hand make a key that fits neatly in the recess. I did this years ago on a model 49 that was continually shearing the key on the clutch basket [before they put splines on the shaft] I also made it out of a much tougher steel than the original which was mild steel. If you have access to a lathe its not that that difficult - just make one a few millimeters oversize and file to fit. Cheers Greg

The Piuma is quite a bit different to the earlier all green models and rides a whole lot better, they have different forks [marzocchi] , different triple clamps, different rear shocks, lighter flywheels in the engine, significantly different frame [lightened in almost every area] and of course the alloy wheel axles/spindles - makes for a much nicer lighter ride

Paul Arnott at the Hell team would be your best bet for the kickstart. There was a rumor years ago[maybe 10yrs] of someone getting a batch of them made here in Newcastle [Aus] but unsure if it ever happened. The kickstart issue is the main reason I sold mine and its a real pity because the last Piumas are an underrated very good bike. Cheers Greg

I am pretty sure they were stocked by many Bultaco dealers not as a Sammy Miller Product but as Hommerlite, I assume Miller would have sold them as well. I remember having a set of Renthal bars that had 'SM' stamped on them, assuming that his shop had added the stamp or maybe it was done at the Renthal factory. Hommerlite also had other tanks as well as the Bultaco slimline unit. Cheers Greg

Yep the extra triangular gusset is factory correct. The first M92 had a single plate gusset on the headstock as the M80's had, and the second series M92[1973] had the double sided gusset with the added triangle, plus a few other mods, the forks had four bolts in the bottom triple clamp instead of two and the diagonal stays from the swingarm pivot to up under the tank were introduced instead of the horizontal ones. I could be wrong but I am pretty sure the M124/125 were the first to have a steering lock. Cheers Greg

The standard Amal is 27mm, so not much of a stretch to a 28mm, worth a try anyway.

JJG and JJF are richer in the bottom rev range - F being richer than G Cheers Greg

The Amal will work fine if the needle, needle jet[106] and slide[3] are all in good condition, these need to be replaced regularly depending on how much the bike is used. It is basically impossible to get the bike to run correctly if the needle jet is worn as feetup said .Pilot should be a 20/25 and main 140/150. The Bings and Amals are particularly prone to wear whereas other carbies- dellortos, mikunis, keihins aren't Cheers Greg

The drain plug underneath the left side case in line with the Bul part of bultaco that is cast into the case. That is assuming it has the original case and not the later model case in which case the drain is actually one of the case mounting bolts- the middle one on the bottom and it has a much larger round head.

Pretty sure the fiberglass tanks are ok as long as there is no ethanol in the fuel.

If your bike has the original plastic tank it is listed as 1.1 gallons. The earlier 159 - 191 fiberglass tanks are listed as 1.4 gallons and will fit straight on. You could also gear the bike up, standard gearing is 11/39, so you can put either a 12T or 13T front sprocket on depending on the terrain of course. Cheers Greg

Yes the 250 barrel fits straight on, with head piston etc. One of the main reasons the 250 feels a little more peppier is that they don't have the steel band on the magneto flywheel. You can obviously take the band off and run the 350 barrel and see if you like the extra revs. Cheers Greg

I have both at home and have tried both. For me apart from the banana looking a bit neater and being a bit lighter the clubfoot performs significantly better in all respects. The engine has a wider spread of power and more torque off the bottom with the clubfoot.The banana is noisy anyway and reminds me of the drop off in performance I get when my gassers exhaust needs repacking. Cheers Greg

The shaft more than likely will be bent where it changes to a smaller diameter just past the return spring. You could take measurements from the magneto case mounting bolts to the hole for the shaft [in the case, as this will be the ideal measurement] and compare them to what you have on the actual engine, this would give an idea of the extent of the bend and in which direction. If you plot it out on a piece of paper, the four measurements will give you a good visual of your problem. Another way would be to make a template out of ply or MDF that mimics the timing case holes. If you bolted this in place again it would show you the extent and direction of the bend, you would need holes/cutouts for the flywheel and sprocket and a larger hole for the kickstart shaft. You can use a try square against the shaft and template as you try to straighten it. However Its going to be a bit of a gamble trying to straighten it while still in the bike.

I thought the 199A ones were slightly shorter, as the newer ignition case was/is narrower by about 10mm

I had a similar problem and it turned out to be a brand new set of points that had a poor connection where the wires attach as the hole was not fully tapped through. It took me countless hours to find the problem as I thought the wires were tightened up against the screw, but the screw had bottomed out before putting pressure on the wires. But as everyone has said replace the condenser first [I bought one from a mower shop once out of desperation and it worked fine] and check all your wiring joins as well as the kill switch and your earth. Cheers Greg PS a faulty condenser can still give a reasonable spark when you are kicking the engine over!

It makes sense that they would do that I had a quick look in my shed and found two leftover springs one is 475mm long 59 coils and 3.9mm dia steel the second is 463mm long 50 coils and 3.4 dia -so a fair bit softer I can remember trying some Alpina springs back in the day so the longer one could be Alpina but I am not sure

The M158, 182, 190 250's have shorter sets of forks than other sherpas and I would assume they need different shorter springs. I am not sure of the actual measurement but your supplier should have known that. My guess would be the springs protrude about 20-25mm out of the top triple clamp before assembly, which is a lot less then yours. Inmotion list Sherpa forks at 500mm so I reckon you have springs for the standard forks and the 450mm one in the bike was the correct length original. Cheers Greg

All swinging arms from 158/159 250/325 onwards will fit. They were lengthened from 182/183 onwards [about 10 - 15mm] The shorter ones have a triangular rear shock mount and the longer ones have a rectangular shock mount. I am pretty sure a 199A arm is just the earlier one with a gusset welded on, which wouldn't be difficult to copy. I rode Bultacos for years in competition, and still do, and never bent or twisted a swinging arm and I would think I you are going to restore the bike and ride it in the occasional event a standard swinging arm would be fine. I have however seen a couple of bent ones and I was thinking it may have happened if the bike was ridden with one bent rear shock, causing one side to 'bottom out' before the other. Bent shocks back in the day were very common and some riders would continue to ride the bike in this condition, particularly if the binding/bend didn't occur until close to full compression, as this was difficult to feel. The original Betors were very good when new but did not last very long and were very easy to bend. The bike you have bought looks very good and original and should prove to be an easy and enjoyable restoration. Cheers Greg

Plus Dabill and Grattarola in the top ten if they stay on Gas Gas and Farre, Price and Noguera just ouside of the top ten.

They didn't even make 300 gassers when the alleged incident occurred Brian Robin Trump 650