woody

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.

It's a 1978 model 199 if it's a 350 or a 198 if it's a 250. Originally silver frame and red plastics and mudguards.

If you want footrest brackets that allow you to kickstart the bike without folding up the rest, then as mentioned above, TY Offroad make them. There are pictures on their website. They sell the new fixing plate/bracket, then you buy your own footrests. They give the bike a more modern stance by lowering the pegs (maybe back a bit as well, not sure) and they are made to accept any of the modern type rests from Hebo, Apico, S3 etc.

Brake arm is positioned like this with a longer torque arm

Half links aren't available from all chain manufacturers and as someone else mentioned those that you can buy don't necessarily fit other chains, so you may not get one that fits your chain. You should be able to push the wheel all the way forward without the brake arm fouling. What may be causing your problem is that your brake arm is from a Pursang and the way it is fitted means that it sits on an angle and so is closer to the swingarm. The Sherpa arm is straight, not bent and so has more clearance because it sits vertically, not on an angle. Try removing the arm and turning it so that the lower half points up vertically and then see if you can move the wheel further forward (obviously you'll need to disconnect the rear brake to do this but all you're trying to achieve is to see whether the arm position is stopping the wheel going fully forward) Or you could fit a longer torque arm which will lift the spline above the swingarm as it will rotate the brake plate anti-clockwise I've found with standard sprocket sizes, especially on the later bikes which are 11:39, the chain is always too long or short to get proper adjustment. I run non standard rear sprocket sizes which helps get the chain adjusted properly (ie: if you had one or two teeth less on your rear sprocket the chain wouldn't be so tight) So sprocket sizes are another way of overcoming a chain that won't adjust properly. Yours are 11:46 standard. If you fitted a 45 for example, the chain would be less tensioned and it wouldn't affect your gearing noticeably. Depends on how you find the gearing you have as to whether you'd want to change. Your rear sprocket looks a little bigger than 46 but hard to tell. What fuel tank have you fitted? Fibreglass, plastic, alloy?

It's not, it is too hard for someone who has just entered into trials. Even for riders who have been riding for years if they aren't up tp a certain standard. It's a national standard event and even the 'easy' course is reasonably demanding as it's not just the sections you have to deal with. There are a good number of miles that take you over moor crossings, rough tracks, bogs etc and you're riding for around 5 o 6 hours without much rest. It's impossible to give an indicator of what level you need to be at as it's difficult to 'measure' someone's ability. One option would be to find riders in your club or area that have ridden it, look at what level of rider they are and how you stack up against them if you ride the same events, see how they find the trial, look at how many marks they've lost in previous Lakes events and it should give you an idea of how hard you'd find it. It's a wonderful event but if a rider isn't good enough, they'll crash continuously, hurt themselves, damage the bike and their confidence and probably hate it.

Did it run ok with the original carb. Did it rev out ok. If yes and you refit that, does it still run ok. If yes, then it's definitely your new carb Allens are mainly motocross/enduro and have little or no experience of trials, or at least they hadn't when I bought a carb from them. The jetting in a carb for trials was and presumably still is, based upon feedback from customers, which doesn't necessarily mean it's going to be right. Mikunis are very hard to jet from scratch as they have a massive range of needle / needle jet combinations and if the mixture is wrong in that particular range it's difficult (impossible for me) to know whether its the needle that's wrong, the needle jet, or both. The original needle jet (emulsion tube) on the TY was an N-8 so you want the equivalent of that for your carb and the needle to go with it. There are several different series of VM roundslide carbs and not all use needle jets in the N-8 range - see on Allen's website, the range is mind boggling. I think the carb with the pull out choke is jetted differently from the carb with the lever choke. If you tell Allens that the original carb, Mikuni VM26SS used an N-8 and a 4V1 needle, they should be able to check you have the right combination. There are two types of needle jet / needle and they must be of the same type. If one or the other is the wrong type it won't fuel properly (don't ask how I know this...) Also, the original main jet size of the old carb won't correspond directly with the new carb as the TY would have had autolube and I think that meant a bigger main as they were around the 160 range standard - that's too big on the new carb for pre-mix. They also had a funny numbering system as they can be as high as 280 but they weren't actually that big. That's speedway dope size... You're more likely going to need around 120 / 130 for the main. Bultacos / Ossas use a 130 generally so the TY250 should be around the same, pilot around 30 / 35 and slide 3.0 So what main jet is fitted at the moment out of interest

What size main jet is in the new carb

No pictures but when I did mine it's apparent that the selectors will only fit one way as no two are the same fork diameter and unlike the 5 speed you can't fit any of them upside down losing two gears if you do...

I use a BP7ES with no problems

ok, misunderstood your last post, thought you'd been there. I have someone to do hubs, just wondering who the person you used is out of curiosity as he's near here

Does he live by a river?

Just curious as to who the person is in Birmingham as I've never heard of anyone here that does them

In Birmingham? Where?