woody

It's possible to assemble the gearbox with one of the selectors upside down, or wrong way around, forget which. If this happens then you get no 4th or 5th gear, only 1, 2, 3. So if the engine has been rebuilt this is a possible cause. If this has happened since you've been using the bike with all gears working, then you could have a broken or bent selector. As per the question above, when did it happen, after a rebuild or during use.

Generally smooth motors, but some Sherpas can make some strange noises when you drop the revs right down to nothing and ride at near stall speed, nothing untoward but possibly the grating noise you describe. I've heard it even on a fully rebuilt motor. No idea what it is but it's only at that point where the engine is almost stalling. There could be other causes, ignition flywheel catching the inside of the timing case if it has previously been damaged by the chain coming off. Clutch crankshaft weight loose, even the mesh between the bottom frame tubes touching the engine through being dented from rocks can cause vibration noises you may think come from the engine - same for the alloy bashplate on the later bikes. If it's anything more than that then you're going to have to look at the possibility you may have the onset of main bearing wear, or just a worn piston that is noisy but doesn't cause any loss in performance.

If it's a new frame kit you mean, contact Jim Pickering who makes the Drayton frames. There are a number of satisfied customers with these now. 07850836571

Yes, 1 down 4 up. The older Sherpas aren't very quick on the road Gearbox = 600cc Clutch = 300cc - if you have the original steel plates, use ATF

Short memory TL - last year. Pedrosa Lorenzo, Brno.

It doesn't look too bad to be honest, I bent one worse than that on the left hand side and it caused the shaft to bind in the casing, so it did affect gear changes. Nothing damaged inside though and I'd guess you'd really have to hammer it one to do so. If it is changing gear ok and the oil seal isn't damaged and not leaking oil then you won't hurt riding it a bit longer. Eventually though, it may prematurely wear the oil seal on the shaft. You can get them from ebay from time time but you're reliant upon the description being good - ie: not bent and with good splines. Better off to try Bultaco UK, Sammy Miller or John Collins (JC Motorcycles Port Talbot) to see if they have a good used one. They'll know if it is good or not. Bultacos by the way are one of the more straightforward engines to work on.

Rossi rode well, no denying it, but yes, the Eurosport duo went way over the top. All of a sudden, we're back to the days when a myth was created, only one rider knows how to overtake, only one rider can ride on worn tyres etc etc. Gets a little irritating pretty quickly. If another rider had made the mistake he made at the begining which nearly took him out and another one, maybe two riders, there'd have been criticism for sure, but for him, it's an acceptable risk. Double standards. Fact is there are only four full factory bikes, so 4th should be his worst finish, he shouldn't have a satellite bike in front of him. Cal was unbelievable but where he had the speed advantage over the Hondas around the back of the circuit, he couldn't use it as two Hondas were in the way. Maybe his bike just didn't have enough go to get up the inside of them, maybe he just couldn't do it, who knows. He must have been gutted when Rossi breezed past him up the straight. Something tells me he's not going to get any upgrades as they will not want him harrassing the factory duo, although I daresay Lorenzo had something in reserve, just in case.

Only you know if it's affecting gear selection as you're the one changing gear.... However, if you need to change it, it's an easy job and only needs the clutch cover removing, the shaft can be removed without removing anything else. You may have to cut the splined part off the shaft to draw it through the hole in the casing though, if the shaft is too bent..

Who care's ? He does, it will probably needle him forever that he couldn't ride it, particularly so given the results his hated rival got on it. He and Jerry Burgess accused Stoner of not getting the best out of it due to lack of set up knowledge and not trying hard enough and attributing the crashes to pushing too hard too soon in a race. They said rider error, not the bike. Ooops. Dovi's gone well on it tonight.

Yes, it's much easier to do it properly with the cases split. I've never tried to replace the spring with the engine assembled but you may as well have a go now the old spring is off... Only way I can think I'd try it is locate the spring into the shaft and then get a long / thin nose pair of mole grips and attach them to the spring just below the 'hook' part that locates on the stud with the lock nut. Then with the spring firmly held in the grips try and wind it round the shaft and locate the hook on the stud. That's how you have to do an Ossa kickstart spring. Not sure whether you'd have to go around the shaft once or twice to get the right tension but I guess you're going to have fun finding out...

Is the engine assembled or are you rebuilding it?

Patrick, I can't argue with your physics as I have no qualifications in that subject. I can only speak from experience. The 300 Fantic I tried with specifically designed large volume airbox to boost performance was no better than a standard bike. When I've run my Ossa with no airbox, just a piece of gauze across the carb intake, there was no difference in performance and you can't get a better airflow than straight into the carburettor with no airbox in the way? The engine can only draw as much air as it needs and if the stock airbox doesn't stop it drawing that air it's difficult to see how a bigger one will make any difference - like the 300 Fantic example, or my 320 Majesty?

This is one I made for a 320 Majesty using a modern airfilter but 175 could be done the same. I did it not for performance but for the ease of removing the airbox for maintenance because the original airbox is a lot of work to remove. Also it was broken. There was no difference with performance.

The puller I have is tapered so it doesn't damage the threads. The Ossa sleeve can also fly off pretty quick so at least you know what to expect after the Monty experience... Most damage I ever did was with a MAR rear wheel spindle. Because they used to bend (i didn't realise this at the time) they could be a bugger to remove. I had one stuck once, half way out and as an enthusiastic teenager employed the hit it as hard as you can method. I was absolutely battering the drift with a lump hammer and eventually it came out - like a guided missile it flew arrow straight across the garage and went clean through my dad's stock of flourescent light tubes, reducing them to powder in a nano second... I also put the front wheel of the same bike through a french window following a badly executed pivot turn off the step up to it. Had to say I did that with a plank of wood.

I don't understand why? I could if the engine was struggling to get air due to the airbox restricting airflow, but it doesn't. The TY175 engine doesn't have flat spots and it will rev out cleanly so it must get enough air. A larger airbox won't allow it to draw more air than it needs? The airbox on my KT250 was smaller than a TY airbox but still provided the 250 motor with enough air. I've ridden a 300 Fantic with a large volume airbox and flatslide carburettor and it was no more powerful than a standard bike. The standard bike actually felt better...

Tubeless tyres don't seat well on the Japanese tubed rims so you're going to be taking a gamble if you try and use it. Even if you get it to seat when fitting, you run the risk of it dropping into the rim when riding. Usually, after fitting, they drop off as soon as you let the pressure down, normally around 10psi

Actually it was a very stable bike and was brilliant fun on the road. Gave a Golf GTI a hard time round the switchbacks of Moidart one year and had fun with a bunch of trail riders on big KTMs another. I'd punctured the rear up on the Ben one year and didn't have time to fix it but it was also doubtful I'd be able to limp back to FW in time either, so I'd resigned myself to exclusion, having had a miserabale week fitness wise with back and wrist problems. Anyway, coming down off the Ben, Alan Sagar was just about to set off having seen Paul through. He flagged me over and offered me Paul's spare wheel to get me back. He set off in the van leaving me to fit it. Never forget his face as I steamed past his van a few miles further down the road. The rear had 20 - 30psi in it and the TYZ was really singing on that occasion. Worst bike I rode in Scotland on the road was a '98 315 which wanted to knock itself apart during roadwork and needed constant throttle adjustments to keep it running clean and from knocking. The 4RT was a huge improvement over that thing and was quite relaxed on roads and forestry tracks.

Unlikely those were the original bushes as they would normally be a bronze bush with a steel inner sleeve. Yes it will have to come out to fit new bushes, you can get the complete kit from Bultaco UK - bushes and spindle

You can get one from Keith Lynas in the USA at Ossa Planet. I don't know where else you can get one from http://ossaplanet.com/partspage.html To remove it without the tool you will have to make something. You need two circlips to fit into the groove on the sleeve. Behind the circlips you need something that will pull against the circlips, then if you fit a normal puller onto this, you can pull the sleeve off, but they are very tight so whatever you make needs to be strong enough not to bend. I made a 4mm thick disc (ie: like a very large washer) with a hole with an internal diameter hat would just slide over the sleeve. I made two semi-circular circlips that fitted into the groove to form a complete circle and then pulled the disc forward up against the circlips. The disc centre was recessed a bit so that the circlips fitted into the recess and were held in place. I could then use a 3 leg puller to pull it off. Some come off easier than others, some need repeated tensioning and tapping with a mallet to get them to release. And maybe heat although I'm not sure about heat as it transfers through to the crank as well presumably so everything expands together? The more stubborn ones can let go with a bang and land a few feet away, so don't stand directly in line with it...

Had one of the first 05 models and remember it being pretty good on the road but it wasn't so good on fuel. It ran dry on the Thursday morning run from FW up to Chairlift before the first fuel stop and I was definitely not thrashing it. Being relatively new I didn't know how reliable it was going to be so it was nowhere near flat out, just cruising. Also ran dry later in the day but at least it was within pushing distance of the fuel stop. It ran dry in the Lakes 2 day later that year as well. No idea why, it was absolutely standard spec. Couldn't touch the TYZ for making up time on the road though which would do a snatch over 80 and it would do it all week long when needed.

Isn't that the Europa? Available as 240 or 325cc. Maybe they called them the Vega elsewhere and did them in red? In the UK, the budget version of the Europa (which was white) was called the Weekend and had a red colour scheme I thought Scarlett rode the SR which was a rare model

USD250 to have a liner...??? It costs £40 - £50 here. It would be cheaper to send your hub to Bultaco UK for an exchange item.... Virtually all of the chrome had gone from mine when it began to wear through the alloy, but the trial was held on boggy land and the stuff acted like grinding paste inside the hub. You'd have to cause some considerable wear to render it useless as it has to be machined out a bit to take the liner. I'd imagine there's life left in it yet as it took a while for all the chrome to disappear from mine.

Send your shoes to Villiers Services who will get them relined with a softer material. They'll make them oversize if you like so that you can skim them to fit the hub better but just the linings themselves will improve things.

They can't, two routes and their trials are absolutely ideal for novices and inexperienced riders, even the hard route is such that a decent novice rider can tackle it. You can ride the most clapped out ill-prepared old bike on the easy route and still get around, no need for spending thousands on a bike to compete in their events. Only if last minute weather changes occur will they turn out to be more difficult than intended, but that is a problem any club faces with that sort of terrain. They've always run on Saturdays and used to regularly get up to 50 - 60 riders until a few years ago, sometimes more. You'd see people riding their trials that you wouldn't see at any other. Blokes with new bikes and all the gear to blokes in wellies, jeans and 70's helmets riding all manner of stuff. You'd see early 90s bikes which you just don't see anywhere else. They pitched the sections right for the standard of rider they had and it worked well. Nothing has changed from the club's approach but what has changed is that all those 'odd-ball' riders have disappeared and in addition to that, fewer and fewer Midland Centre riders are bothering to ride now and this has been happening for years, although it seems to have increased in the last 3 or 4. We had about 16 riders at our last club trial, although a clash with another club didn't help - both trials had been rearranged from earlier cancellations. There is no easy answer. Very few new riders are coming through, a lot of the older riders don't ride anymore and most centre trials have the same names as a riding list from the late 70s early 80s, just less of them. Life has changed, trials is no longer a family sport where mum and the kids came out with dad to watch him make a pratt of himself or help observe / organise. Therefore the kids don't get involved and take the sport up themselves. There are too many other distractions these days whereas years ago it was generally a choice between bikes or football. Most riders turn up on their own. Most families are 2 car owners and rider's wives can go their own way and do what they want and take the kids with them. Very few owned 2 cars in the 70s so a trial was a family day out. The Kings Norton event was an unfortunate clash with a Miller round but I'd say that only took 10 riders at most. Last year it clashed with a Normandale round which would have taken more. It's a pity as it is a good trial and would actually make a good Normandale round itself. Hopefully next year, no clashes. But to get a decent entry, it is going to take riders from outside the centre to swell the numbers. In June we (Stafford Auto) run a Saturday afternoon trial with bar-b-cue afterwards, an event originally intended for Pre65 and twinshocks although modern bikes are catered for with an additional harder route. Try as we might, there are few riders from the actual centre that come and ride. Most of the entry comes from East Midlands, Staffordshire Moorlands or local AMCA and none of the local Pre65 riders from the BMCA ever come. We put 3 routes on with a 50/50 between the easy and middle route which caters for just about anyone. Still it's a poor entry from the actual Midlands clubs despite it not clashing with other events. What the answer is I've no idea but the future of the Midland Centre doesn't look too bright and in a few years when those remaining 70s / 80s riders begin to think twice about getting out of bed on a Sunday morning, it will look even worse.

It's not a later Montesa yoke. The alloy yokes were all the same appearance with bolt on bar clamps.