woody

It's an assumption to say it's a bottomless pit in terms of money. What's the objective, to make useable to ride? Or restore to as new condition? The former could possibly be done quite cheaply, the latter is the bottomless pit route, but that applies to any bike. Aside from the piston, from what I can see, the major missing components are the front pipe, seat, kickstart and gear lever. I've seen M92 / 125 / 151 front pipes come up on ebay USA a few times, so if the original can't be found it should be able to get a replacement used item. At worst, they're available new. Kicker and gear lever are no problem. Hugh's does a seat base and a local firm could cover with foam and vinyl - not too expensive but seat is not essential to get it running. Just because the piston has been removed doesn't mean the bottom end is trashed. It could have been something like a snagged ring that caused it's removal, or a mild heat seizure. The cylinder liner should give clues. Mains and big end condition can be gauged by spinning the motor and listening for dry or scored bearings. Mains can be checked for vertical movement in the crank, big end checked for play in the crank. The bottom end of the motor could be quite sound. If so, a new piston is the biggest single expenditure to try and get it running at about $180? Plus the rebore. I don't know if that's expensive to you guys or not. The gamble is, spending that much and then finding that despite the bottom end checks, it does turn out to have unacceptable wear when running. If the bottom end is shot it's another $350 - 400 for a complete rebuild? So something like $600 to sort the engine worst case. Plus some used parts. So for $600 and a bit you could have a useable runner but whether it's worth it depends upon what you want to do with it. If you keep it you just absorb the cost as with any bike. If you come to sell it you have to consider that outlay plus what you paid for it and whether you could at least break even. I don't know what those bikes fetch in the US.And whatever the bike cost to buy. In the end, although it's just an old dirt bike, it's a Bultaco and in the history of trials they have a bit of 'provenance' and status, probably moreso than any other marque. And if you want more oomph than the TY, this will certainly give it you. The TY will be far easier to ride, but it's not a 'taco....

That end to the pipe is not something that was ever crafted in the Bultaco factory... This is the original set up

Compared to the TY175 it will feel bigger, heavier and the engine will pull your arms out. The bike isn't as nimble as a TY175 and won't be so easy to ride, but it is, ultimately, a more capable bike. They were aimed more at expert level riders in their day, not novices. Only you can decide which you prefer once you've ridden them back to back. Your exhaust silencer box is a Sammy Miller aftermarket period alternative and they were used without a back box. The standard silencer was the same shape effectively but steel. As mentioned above, they had the small triangular back box from the factory but they were generally removed before the bike got used as they stifled the motor.

A HPI of the VIN is the way to go if it can be done properly in order to find out if there is an existing reg number. I have heard of instances where the wrong reg has been returned as the VIN number entered just happens to be part of a longer VIN of another vehicle and someone hasn't paid due attention... Even though Montesa are the manufacturing factory of the bike, DVLA will only accept proof of age from an agent on their approved list. Montesa SA aren't on it.

First thing to do is get your chassis number registered on NOVA. You don't need a dating certificate or insurance to do this. Your vehicle details must be on NOVA before you apply to DVLA. Problem with VMCC is that the person who was dedicated to providing the dating certificates and all other dating matters left the organisation and as far as I know, wasn't replaced. She had built up substantial knowledge of off-road bikes over the years which helped with a quick turnaround. Therefore processing dating requests through VMCC is now slow. It may be worth trying the company I mentioned above. Or, paying the £95 for them to do it all for you seems good value to me.

You need a dating certificate from a DVLA approved source in order to get the age related number. Before applying to DVLA your bike needs to be NOVA recorded by HMRC - search this particular forum for NOVA for more info You can try the VMCC in Burton Upon Trent for a dating certificate. They'll want a picture of the bike itself for profile ID plus one showing the frame number. Or you could try these people who will undertake the entire process on your behalf if you require for £95 - not a bad thing if you've not been through it before... Not used them myself in that respect, maybe someone else has who could comment. http://www.dvlaadvice.co.uk/

Yes and no Ross. The grip factor is excellent, just as good as the tubeless. The sidewalls let it down. I have had one or two where the sidewalls were stiffer from new but softened with use, but 95% have been too soft from new. I tried one recently in my Ossa when out running in the bike and could not do a cambered section, the rear tyre rolled down the camber and turned the bike around every time. Swapped the wheel for my tubeless one and section cleaned no problem. If you ride solely on rocks and can afford to run a little more psi than normal, say 5 - 6psi, it goes someway to negating the soft sidewall. If you ride mainly mud, cambers, roots etc, then 5 - 6psi is no use, there isn't enough contact patch for maximum grip. With the tyre at normal pressure of 3 - 4psi the sidewalls give and the tyre rolls on the sidewall on cambers, over the points of rocks. I've even had them roll under hard throttle on flat ground in a straight line when going at steps etc. which rear wheel steers the bike offline. It's not so noticeable for lighter riders and it's not so noticeable if sections are fairly straightforward and on the easy side where grip isn't paramount. So depending on how someone rides and the level at which they ride at, it can make a difference I guess. But once section severity increases and grip is at a premium requiring the lowest pressure, the sidewalls cause problems. Don't know why they don't give them the same construction as the tubeless, It can't be that difficult... .

Yes it's the only tube type worth using, but the sidewalls are soft and the tyre can roll on cambers and rocks. Depends on your weight, the temperature, pressure etc. If you run at 6psi it helps stop it rolling but grip will suffer at that pressure, depending on what you're riding on. The Michelin tubed was useless as it was no longer a tubed version of the X11 You can use the tublis system to keep a tubeless tyre on a rim. I used it on a KT250, which, like the Yam, won't hold a tubeless tyre on it's rim. If you can find someone to show you how to modify the bead of a tubeless tyre to the same profile as a tubed type, that's another solution. I've never done it so can't help.

What's a sense of humour got to do with it? People have really lost the plot as to what 'twinshock' trials is and is about. If it needs explaining any more than it has been it really isn't worth it.

You didn't actually say just what is wrong that needs repair... Just the O ring?

That's the tube type, they've been the same since they were introduced. They're inconsistent and some are better than others but generally they are too soft. For lighter riders it's not so noticeable as they don't load the sidewall so much but once you're over, say around 11 - 12 stones, it becomes noticeable. Especially when the weather is warm. The tubeless IRC has a different sidewall which is stiffer, although I've had a couple which have been too soft in recent times and rolled too much, but that's in over 20 years of using them. The tubeless work fine with a tube on Akront rims but I've never been able to get any tubeless tyre to hold on Japanese rims, they generally drop into the well when the pressure drops below 10psi. I guess altering the profile of the bead of the tyre could get around that, to make it the same as a tube type but I've never tried it.

A bit too quick on the button with the last post, I meant to post this link http://www.classicmechanics.com/news/2012-10/revitalise-worn-out-plastics#.VKc83nsvspd Details of the refurb service for plastic tanks. I think someone I know has had a tank done, can't remember. I'll check and if so I'll post the details

Definitely a 348 tank? They were always fibreglass as far as I remember. Only the later Cota 350 and MH349 were plastic I thought

Are you sure you're reading the numbers correctly. A 210 is a Matador, the picture is definitely a Sherpa. Not the best picture but from what I can see it has the features of a 175. Colours mean nothing as it could have been stripped bare and repainted, engine / forks could have been stripped and polished The 175cc is a model 221 so is the first 2 missing / rubbed out? Are you mis-reading it. The digit following the 221 would be a 0 so if your missing the first 2 it gives 210. It's definitely not a model 210. Both the engine and frame number should be preceded by a letter M for the motor and B for the frame, so M-221 and B-221. The M and the B may also be preceded by another letter, can't remember.

210 is a Matador chassis number. The 175 Sherpa has a 221 chassis and engine number

I had a manual for the 247 I once had and the problem with them is that they don't give a written description for the part number, you have to guess from the picture 123 does look like the valve washer, 124 being the valve body. 027 looks as though it is the second part of the valve washer assembly, ( the part that is the ring with holes in on the Bultaco forks - replaced with a square shim on some 340 forks) Not sure what 025 is but 023 is the piston with 116 the circlip that secures it to the damper rod. You reaslly need someone with a set they can strip and look at, they are the same forks on the 348 and early 349, probably 172 and early 200 as well.

Yes you need NOVA registration of the chassis number before DVLA will issue a reg. Engine number being different isn't an issue, they won't care. NOVA was never intended and therefore is not designed for registering old vehicles but DVLA don't understand that so you just have to play the game. It's why it's not straightforward to complete the form. I did it over 12 months ago when it was still fairly new and I had to print the form off and complete it manually and submit it by post. There was a flaw in the design and it was impossible to complete it online. Not sure if it is still the same. Fortunately HMRC were very helpful. They aren't really interested in old vehicles, the system was introduced to stop people directly importing new vehicles and registering them with DVLA without incurring customs duty etc. They seem happy to accept that customs duty would have been paid by the legitimate importer when the bike was imported from new and that being offroad bikes, many may not have been registered originally or, may have lost there registration details over passage of time. In the section about who the vehicle was bought from I just put private sale however many years ago, no details available. I put a covering letter with it explaining that the vehicle was first imported in whatever year by Commerfords who are no longer in business and that duty would have been paid by them at that time. If they're happy they just add the chassis number to the database. As long as it is on there DVLA will begin process of your application. HMRC were very helpful with my telephone enquiries. Unless things have changed, DVLA won't accept a dating letter from Bultaco UK as they are not on their approved list of agents who can verify a vehicle's age. There is a list on the DV;A website somewhere, or you could phone and check. I used the letter from Bultaco UK as evidence of the age to get VMCC to issue the dating letter but I'm not sure how well they perform this service now as the person that used to be dedicated to dating letters left, so may be worth checking with them first. Also, as most insurance companies only offer insurance for a 14 day period against a chassis number, it may be worth checking this with yours. If that is the case, don't take out the insurance until you actually submit the V55 to DVLA, otherwise your insurance will expire before they process your application, and some companies won't extend the 14 day cover, leaving you in s h 1 t street. If you search for NOVA in this particular forum you'll find other topics about it with more info and personal experiences of others.

I thought they came small enough but maybe not after all. Honda fitted them to small bikes such as XR75 - too big?

My money would be on a GXL

Did you ever have a MK3.... You couldn't make them any worse

Looks like a bad position for the oil cooler, no protection, could get caught or drop the bike on that side and it's easily damaged which could be end of trial Pit bike oil coolers look about the right size, usually on ebay.

You'd have to be nuts and I doubt it would be in favour with the traffic police, if at all it's even legal. The view of the vehicle number plate is partially obscured as a minimum offence. Then imagine if it drops into gear whilst in transit.......

It's been a while since I rode in this event so can't remember the course, how much roadwork is involved? Is it just a road crossing or short stint down a lane, or is there some distance involved?

News from the organisers for next year's series There are 8 rounds, 7 new venues, 6 new clubs. Our aim is to rotate the clubs and venues each year to keep the series fresh, there are now 15 clubs interested in hosting events. 22nd March Congleton MCC Mow Cop 19th April Nene Valley MCC Daventry 14th June. Red Rose Classic Lancashire 26th July Zona 1 MCC Gloucestershire 9th August Cornish Centre Wadebridge 23rd August North of England Newcastleton 13th September Aqueduct Classics. Llangollen 26th October. Central Wales Auto. Knighton Website currently being rebuilt by Kia and should be more user friendly in the future. Some rule changes and a new class to follow! Follow updates via the face book page - National Twinshock Championship NOTE: There may be a change to the Red Rose date of 14th June as there are other classic events on both that and the previous weekend (a Miller round and Alvie 2 day) Updates will communicated on the Twinshock Trials Championship facebook page

They changed the fork legs for a different spindle fitting in '72 with the model 91/92 From the model 91 the spindle nut is recessed (like the 198a) along with the new style conical front hub Prior to that, the spindle nut located on the outside of the fork leg and the front wheel was the older style, not the conical type You should be able to modify them ok, from memory. You have to be careful with Bultaco forks, much of the components look the same but there are subtle differences. The forks on 250 models from the 158 to the 190 are shorter than the 350 forks from the same years because of the different frame. The bottom yoke is also not as deep. They reverted to normal length from the 198.