woody

The 159 is the one I meant as it's generally referred to as a '76 bike, even though it was introduced in '75. But I think I was wrong anyway as the previous model may have been the first with the head steady

They don't all have a head steady, only '76 on.

Bultaco UK (In Motion) JC Motorcycles, Port Talbot Sammy Miller Product Any of the above may have new or used. Anyone on ebay with parts for sale from breaking Bultacos may have some The head doesn't have studs, it uses the four cylinder studs and in addition there may be two or four bolts that locate into threads in the cylinder (two or four depending on which model you have)

That's due to the ignition, it makes them a bit lazier off pilot.

I think there are more of the Cheney converted bikes than is generally perceived. There were only a few that were full Cheney frames but a larger number (20 or so?) were made by converting the standard frame and these could be bought I think, they weren't just for the supported riders. Mick's cantilever Yam was from '73/74 but they didn't keep with it for long and they were back to twinshock by '74/75

I don't know much about the later bikes but the MAR cantilever had 3 versions I think. As mentioned already, Cheney made about half a dozen of his own cantilever frames as well as converting a number of standard Ossa frames to cantilever. Keith Horseman also made some cantilever frames for Ossa UK along with is reed valve conversion. I think that John Reynolds rode the Horseman framed bike whereas Chandler, Guy and others mentioned rode the Cheney bikes, being Southern riders - but I could be wrong about JR, struggling to remember what Keith told me many years ago. Keith also made replica frames many years after and one was used in the late 80s by a clubman rider who rode it in the SSDT. It's in Don Morley's book but I don't have it to hand at the moment. So your bike, if it has SSDT number fittings, could be that one or one of the Ossa UK bikes As regards which class to ride it in, I think people have to be pragmatic about it. It's a bike from the mid 70s and from the twinshock era. It's in no way as competitive as a mono Fantic, Yam, Beta etc. It competed against the bikes from that era in its day and in classic trials today it should be no different. It should go in the twinshock class. To put it up against mono Yams, 305 Fantics is ridiculous.

Nothing in common apart from the name. Completely different.

Your tank has definitely flared at the front, you can see it in the last picture. Normally, you can just pull it in on the bolt but as yours is painted I wouldn't try it as it would probably crack the paint. You could try heating it and gently trying to close it back up again Nice finish with the bolt heads

360 will work ok on the M80 Standard length was 350mm so for the same damping and spring rate, the 360 will lift the rear slightly with the rider on board which in turn decreases head angle and quickens the steering - in reality, barely, if at all noticeable. The Betor shocks don't have aluminium bodies, the main body is steel. Alloy parts are top mount, collar and spring adjuster Falcons are available for about the same price and he will build them to whichever length you ask for.

The easiest and cheapest method for me is to measure how much the lock stop needs extending to stop the fork hitting the bolt. Then take off the nylon buffer, cut a piece off the shank off a 6mm (or whatever) bolt to that length and tap it down inside the buffer and refit it. The lock stop is now extended. The nylon buffers are long enough to allow a piece a few mm long and still fit properly. The usual reasons that the forks hit the bolt is that the lockstops have been cut down or the plastic tank has spread at the front which means a longer bolt is used. Obviously, the above method won't work if the lock stops have been cut back too far

Same as the Sherpa of the same era. One stud that it drops over at the front, ahead of the filler cap, two bolts at the rear, one either side at the back of the sidepanel. There should be a lug on the frame either side for it to bolt to.

HFS Clubman kit in the forks

Don't worry about it, there is no problem with the 4 speed. Most events are pre70 anyway so even if it isn't on a pre65 reg number no-one is going to take any notice. There are two clubs, maybe three, that scrutineer the bikes and get fussy over what it is and none of them are anywhere near here so unless you're traveling a long way to ride, there's no issue 4 speed is no problem in local BMCA, other local classic clubs, Sammy Miller, British bike series etc. Even the pre65 Scottish take them if you're thinking of entering that

No-one checks documentation, why would they? 4 speed Bantams have been used in pre65 events for the last 20 odd years, it's not an issue. Why now, out of interest?

I've never used a half-link no, no matter what gearing I've used. I've used 41, 42 and 43 at various times on the 340, just depends what they had in when I needed the sprockets. I think it's on 42 at the moment but as I've got 2 B's, one on standard gearing and a M92 that isn't on standard gearing plus 198B that's on ??? gearing, I get a bit confused as to which bike has what sprockets from memory...

Ultimately, regardless of the standard gearing, you fit what you're comfortable with in terms of what you use the bike for. Standard for a 199a is 11:39 but this is high for use in tight sections, or, if you just want to absolutely crawl it without the clutch. It's the same gearing for the 199b and on mine I use 42 on the back as I like to gear down - just personal preference. The A and B have the same 1st gear ratio The gear ratios on all 5 speeds, right up to the model 190/191 are the same and the standard gearing is 11:46 It was the 198/199 model that had the lowered gear ratios, not the A, but it used 13:46 final drive gearing instead of 11:46. This gave higher overall gearing but with the lower internal ratios it probably made the overall gearing only marginally higher For the A model, they retained the lower 1st gear of the 198/199 but reverted to the original higher ratios of the earlier models for 2nd, 3rd and 4th The 198B reverted back to the original 250 ratios but with 11:39 gearing

Next round coming up - 28th September Run by Hillsborough club Hillsborough - a club with a wealth of experience and a reputation for running good events. Proper trials in proper trials country. Home of the Jack Wood, Normandale rounds, River Kwai, the legendary DT Venue is Ughill, not too far from Sheffield, head out west on the A57 towards Glossop and turn right into trials heaven. Where the old Sebac and then Falcon rounds used to be run in the 90s. Happy days, entries of 100 plus riders on twinshocks and Pre65. Now, at last, a chance to ride there again in a twinshock event. So what's going on? Entries appear to be a bit on the slow side dropping through the secretary's letter box. A gentle plop plop instead of the resounding thud this event deserves. What do twinshock riders want? At last, we have a series catering for twinshocks for a good spread of abilities. Big courses, 2 laps, 20 sections. Ambience, nostalgia, Preston Petties, braceless 8" Renthals, huge looping throttle cables, Preilli MT13s (maybe not, but if someone has, a good opportunity for some p*** taking) No need for road licences and insurance. All held off road. Two routes so no excuse for compaints of too hard - enter the right route. So what's stopping you from entering? Too much pampering of machines and not enough riding them? People treating them as investments? Ornaments? There are plenty being sold, are we reduced to just talking about them now? They're for riding. If you want an ornament to polish and look at get a Harley - or a 4RT If you want an ornament to splash posing pictures all over the net, get an internet bride - me love you lots, me look after you, if you lucky me sucky sucky - but I guarantee that riding your twinshock instead of that will be far less painful and less expensive experience in the long run... And it should be emphasised that a standard bike is perfectly suitable to ride on either route, any thoughts that you need some super trick multi-thousand pound creation to take part are well wide of the mark. This isn't the Normandale series, sections on the hard route are challenging but within the capabilities of early twinshocks.The Spanish Historic class at one round was won on an unmodified 1971 250 Bultaco - on the hard route, and he wasn't too far off an overall win. It's down to the rider, not the bike. So come on you twinshock owners, dig them out of the sheds, remove the fairy lights and bunting and pull them down from the ornamental pedastals, this new series has had a reasonably encouraging following so far and the organisers are looking to build on this and continue with it next year. It needs our support to enable them to do this. Pre65 has had it good for years with the British Bike series, Pre65 Sottish, other big profile Pre65 only events. Twinshocks have had nothing up until now. Now they have. Riders' feedback is always welcome, what do you think of the series so far, good points, bad points, they need to know. Although there is no facility at the moment on the series' website for comments, they do have a link from the homepage to their facebook page which allows people to give any thoughts they have on the series. Let them know. So there it is, this is the last round and what a venue to finish, they don't come much better (unless my memory has failed completely) Get your entries in. For whatever reason, the entry form hasn't been uploaded to the series website, but it is on their facebook page - can't post a link but just search for twinshock trials championship. You'll need to scroll down a bit to find them. Or they're on the Hillsborough site http://www.hillsboroughmcc.co.uk/ So, be there, you know it makes sense. Twinshock, pre65 or air-cooled mono. All welcome.

Not sure I follow you on the forks question as your forks are Sherpa. You have a 199 Sherpa with an Alpina motor so the motor is your only issue The early Alpinas such as the model 85 had the same front end, appearance and dimensions, as the Sherpa of the same era and I'd bet the damping was the same too as it was basically a Sherpa with different gear ratios and a dual seat - possibly ported differently but not 100% sure on that. Later Alpinas were completely different, their design and appearance departed from the Sherpa and the forks are totally unsuitable for the trials bike

Steve Sell, who specialises in Ossa parts, may also have decals, I don't know Call Steve on 07800 778 048 & leave a message he will call you back. Don't have your number blocked though or he might not

If you call him don't have your number blocked, otherwise he might not.

When you say are the early / late motors different, in what respect do you mean. Yours is an Alpina motor so it differs from the trials engine anyway, one is a trials engine, the other a trail so the porting may be different and the gear ratios are different. So you're not comparing like for like. In terms of power, the later square barrel 250 was a bit sharper than the older round barrel - both have enough. I don't think gear clusters are a straight swap between early and later engines as shaft sizes and some gearbox bearings differ. Also, the model 85 Alpina had a round barrel and head so if yours has a square barrel it's from a later bike, so could be Sherpa or Alpina. Richard Allen of Allen's Used parts had a 198a rebuilt motor for sale on his website http://www.allensusedtrialsspares.co.uk/#/bikes-breaking/4560010283 Or there was a 199 motor on ebay recently that didn't sell - you could make him an offer http://www.ebay.co.uk/itm/Bultaco-Sherpa-Twinshock-Trials-Engine-Model-191-350cc-/161403086006?pt=UK_Motorcycle_Parts&hash=item25945fa4b6&nma=true&si=SxeP2mc0uVIYU15V0QdsSiNuIEw%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557 Early and later clutch cases have a different profile and fit the profile of the crankshaft weight. If they aren't a correct match the case fouls the weight and won't mate up. Weights are interchangeable.

Good question. I don't know what happened to the decals from the ebay seller mentioned above as they used have the correct dates There was another seller in the UK that did them but the website seems a bit flaky at the moment and I couldn't find any mention of the sidepanel decal, only the tank http://www.classicbikedecals.com/ Other than that I don't know.

A and B is for the MK1 and for the MK2 / 3. The MK1 came out in 1972 by which time Mick had won the SSDT in 1970 and 71 and the European champioship in 1971, so the decal made reference to those dates. He won both again in 1972 so when the MK2 came out in late 1973 they added 1972 to both titles on the MAR decal, so it should say Euro winner 71 - 72, SSDT winner 70 - 71 - 72. It's this 72 that's missing. Below is a picture of the UK shaped decal This is the Miller decal This is the MK2 decal Decal for the fibreglass tank. You can see the different shape

Thery won't go to 370cc, it's not possible with a Bultaco piston. The only way to get a 325 Sherpa to 370cc is using an Alpina top end and crank as the 350 Alpina has a longer stroke. The most you can get a 325 Sherpa to using the 85mm 360 Pursang piston, as they did in the 340 Sherpa, is 340cc The tank on the 199 was the alloy type originally, a bigger tank than the plastic tank now fitted which is from the next model. The tanks had a different profile at the rear and seats were shaped to suit the tanks. That looks like the original seat for the alloy tank My eyesight isn't good enough to see the rear wheel in detail

The Miller decals aren't quite right, they're too thick in the horizontal section where they sweep to the rear of the tank. The decals on ebay are the right shape from Anglia Vinyl Art but I noticed the MAR Replica sidepanel sticker is missing the year 1972 from the dates he won the European championship. It should be 71 - 72, not just 71. Also, these decals are for the UK style alloy tank. If you have a fibreglass tank the decals are a different shape to suit the different profile of the glass tank. No-one here does them as the MK2 and MK3 all had the glass tank replaced by Ossa UK when imported new, so 'UK shape' decals had to be made. You probably have the alloy tank but just a thought with more bikes coming in from Europe these days.