woody

1. Yes, tubeless rear, tubed front. Tubeless front rims were discontinued a long time ago 2. Possibly, they seal normally using a rubber sealing tape around the rim which seals off the spokes to stop air leaking past the spoke heads. Tubes are sometimes fitted as these tapes are a pain to fit and can still leak. Some give up and fit a tube. If the corrosion is bad the tape won't sit correctly and air will escape. If it's really bad be sure that it's not going to fail in some way. Corrosion isn't uncommon on older tubeless rims 3. Tubeless rims need tubeless tyres whether you fit a tube or not. A tube type tyre won't stay on the rim and the bead will drop off. You don't need rim locks with a tube fitted as a tubeless tyre holds itself and won't creep

Red one (both) will look different from how it was when new as it has been repainted, probably more than once. Catalogue pictures will show you how it left the factory. The numbers are the way to accurately identify it. It's 1971 era frame but it has the wrong front wheel, maybe one from an earlier model, I can't tell from the picture. If the blue one has no number on the headstock it's either been removed or it was a replacement frame from the factory as a replacement would be unlikely to have a number stamped. Maybe the number got polished out in the preparation stages of plating. This is also a 1971 era frame, it is Bultaco not Miller. As I mentioned in a previous comment the forks and front wheel are from a 1972 model It would help if you put the numbers that you have on here if you're not sure how to check them. otherwise you're going to go around in circles The Alpina was the trail bike version of the Sherpa. Early models of both looked virtually identical apart from the Alpina having a similar but larger tank

You need the engine and frame numbers to identify which model exactly. The frame number is on the headstock not under the tank. The engine number is on the r/h crankcase under the exhaust. Early model Alpina had the same frame as a Sherpa which is why you need numbers to identify From the pictures they both look like 1971 Sherpas which was a model 80 ie: the frame and engine number would be B-80###### M-80######

Differs in what way? It depends on which aspect you mean and what you want to do I think physically the actual silencer bodies are the same size model to model although they come off the front pipe at different angles depending on the height of the pipe bend as this differs amongst the 250 models. The 350 models also have different bends The outlet to the rear silencer on the 250 is a smaller diameter than the 350. 25mm OD against 27/28mm OD I'm fairly certain that the inner core is the same diameter on 250/350 The flange that bolts to the cylinder has a bigger stud spacing on the 350 Earlier model pipes aren't a good fit on the A or B models as they had the engine raised in the frame so had less of a bend to clear the underside of the tank. A higher bend will be too close or even contact with the tank and the heat will cause damage, especially to a plastic tank

Yes you can The picture is a 1974 bike but it is the previous model that was produced into 1974, not your bike which was the new model introduced later in 1974. However the differences are very small and for the purpose of appearance yes you can use the picture as from this side it is the same as your bike. The only difference on the other side would be the rear silencer

I'm not sure technical information will help much as it is more appearance that is a bigger issue if you want to return it to original. Although you have a paper with build 1975 the M125 is a 1974 model which carried over into 75, so if you look for an owners manual it is for the 1974 bike, not 1975 as the 1975 model had small differences If you google images for 1974 Bultaco Sherpa you will find an image of the original sales brochure which will help you see the original appearance From a quick look these are the changes I can see:- Brake light switch has been moved, should be on swingarm above chain tensioner Petrol tank sidepanels and seat base have been cut off (tank and seat are a one piece unit) Tank filler cap top missing Rear mudguard brackets have been moved Seat has wrong cover Shock absorber bottom mounting has been moved A plate has been welded in the frame V above the footrest Wrong carburettor and hose, should be 627 Amal MK1 Wrong front mudguard brackets Chain tensioner should have a pad not roller Mudguards are aluminium originally On the plus side, the main frame structure hasn't been altered, the engine doesn't look battered, wheels and forks are correct, exhaust is correct

Just for interest, I ,measured the 151 and 198. The 151 came out as a touch over 52 with the wheel just forward of centre, the 198 was close to 53 with the wheel just behind centre

I've always thought that the wheelbase given in the manual was a bit conservative as when I've measured my Bultacos in standard set up (a while ago) I'm sure they were over 52", even with the wheel forward which it rarely is due to chain length and tension. I'm working on an M151 and a 198 at the moment, both standard so I'll measure tomorrow out of interest. They don't feel that short to ride... When you mention offset it sounds like you're actually referring to the angle of the forks to the steering stem ? which isn't the offset as that's the distance of the forks from the steering stem. Your yokes look like Montesa ? which probably have less offset than Sherpa yokes As Carl said the later Alpina yokes have an offset but run parallel to the steering stem so would reduce the wheelbase slightly. I tried some once but because they were wider new spacers were needed and I couldn't be bothered and you'd have to stretch you mudguard brace to fit or fit it to the inside I've ridden a Sherpa with the head angle tightened and which also had parallel billet yokes which I thought might affect the steering adversely but it steered fine and seemed stable enough

ok, I'll try and explain this just once, as I think that as English isn't your first language you misunderstood what I said. And I don't mean that to criticise your English as it is good, but misunderstanding happens from one language to another. You suggested trying a local supplier or online specialist. Myself and others have done that and in the UK we cannot find the bearings apart from Pyramid and In Motion. I was talking about the UK. and saying that we can't get them here. They are not listed on FAG, SKF or any other sites. That is all I meant, not to criticise you If you have been able to find them in the UK people would be interested to know

Firstly, you do realise that both myself and the person who wants the bearings are in the UK don't you, so how would I be aware of some obscure German make of bearing. You will also note that their bearing size is measured in fractions, not whole numbers so how would I know to search for that, even if I was searching German companies. As for false information I never said they didn't exist, but that they were not available in the UK from local suppliers. If you look back through the Bultaco forum you will find others have said the same as they have been unable to find them either. I also suggested the person who wants them search for himself before using Pyramid if he wanted a known brand Before you respond in such a sarcastic manner (limited view of the world) and then accuse me of posting false information why don't you google "bearing 25x45x11" and see what you get in the search results for the UK. Then have a look on the websites of FAG, SKF etc and see if they list a bearing in that size. Then contact a few UK bearing suppliers and ask them if they can supply that size bearing. Let us know how you get on and the name of any suppliers you find I could ask why you didn't mention your supplier yesterday when you replied if you want to be helpful... With respect to bearing stress loads etc I'm not an engineer so have no idea of what you're talking about and don't care. I replied to you agreeing that it is not a good idea to use cheap bearings in an engine. However, with my limited view of the world, I doubt a steering bearing is going to fail completely resulting in the forks falling off and serious injury to myself, so I was prepared to use a non-name brand. I have used Pyramid bearings in my steering for about 15 years and have never had a failure, they rarely go out of adjustment and I have only had to replace one set on a well used bike in all that time, and that was most likely due to water ingress from repeated pressure washing

None of the main manufacturers supply this size bearing, it's not a standard size. I agree about only using quality bearings in the engine and even wheels but the steering is under little stress and the no name steering bearings have lasted me more than 10 years in some of my bikes with some hard use

Simply bearings don't stock that size. I haven't found anyone that does apart from Pyramid and then latterly In Motion which may well be the same bearings as Pyramid.

I agree there is nothing wrong with the ball set up in terms of efficiency, for me it's just the inconvenience factor when removing and refitting yokes, it's just so much easier with the tapers. I've had the tapers in my bikes for years now though with no issues, only had to replace one set along the way and that was on a bike that has had a lot of use

Personal choice really, when the bikes were new the bars then were much taller than now, 7 or 8" rise so the footpeg position was never an issue. Now the bars are 6" ,max so the riding position can feel a bit cramped for taller riders. The pegs on the 159 Sherpa are close to the bottom frame tubes so there is not much scope to lower them by much, 1" maybe. How far back will get many opinions, mine is they don't necessarily need to go back once lowered but if they do either under or just behind the s/arm spindle.

Give your local shop the dimensions and see what they say, if they can't help they're available at In Motion or Pyramid parts

The bearing is 25mm ID and 45mm OD. The depth of the bearing housing in the frame headstock is 11m. Whether 11mm is the actual measurement of the bearing height I don't know without measuring an original, it may be 12mm. If you can find a bearing 25x45x11 you'll do well. Pyramid parts sell Bultaco bearings off the shelf and as Carl said they are 25x45x12. They fit fine. You'll also do well to find this size at a local stockist. I would guess the In Motion bearings are the same but I haven't used them. I first fitted tapers about 15 years ago and the only source with a direct replacement was Pyramid, no-one else did them and I bought a number to keep me stocked for future rebuilds. Millers sold a kit but they weren't the right depth and needed the big nut that tensions the top bearing machined to make them fit. All Sherpas are the same size bearing

It looks like a model M125 with a few alterations. The engine and frame numbers will confirm the model

That's the mod I was referring to with the Beta kickstart that I did for mine although that's not mine in the picture. I took mine off after trying it for a while as I got fed up of having to reach down to flick it out by hand to use it. The Bultaco lever can just be flicked out with your heel, I couldn't get my heel behind the Beta one

I was wrong about cranked kickstarts, I've just seen a picture of a kickstart from one of the Matador models, the SD, that is cranked outwards so that it avoids the exhaust

You can get the stator repaired by Bradford Ignitions, I had one done some time ago and it still works Or you can buy a complete replacement aftermarket ignition from In Motion The bike looks to be in good unmolested condition

Sammy Miller never did the type of kickstart you're looking for There is an aftermarket folding kickstart that has been recently made by someone in either France or Spain which is a copy of an aftermarket one that was produced years ago by a company called DOA. I don't know if they sold them all or how good they are but they were quite expensive. You'd have to get on one of the Bultaco forums on facebook and ask on there as there was a bit of discussion about them. The old DOA items are very rare and I don't know how good they were in terms of quality, I've heard it said they were poor. What I did some years ago was cut off a Bultaco lever just above the spline. I did the same with a Beta Rev3 kickstart, cutting the knuckle just above the spline which left me with the swivel and lever. Then welded swivel to the Bultaco spline (it looked a lot like the DOA item) This gave a lever with a bottom swivel You could do the same with an Ossa one but finding an Ossa kickstart won't be easy, they're also quite long. I'm guessing this or similar is what must have been done with the one that Feetupfun saw as an Ossa kickstart won't fit a Bultaco spline, it's way too big

Those kickstarts are for the early Sherpas, not later, they fit the 4 speed and first 5 speed models. They bend inwards so if you fit that on your A model it really will clout the frame

It's not uncommon. On A and B models the kickstart is closer to the frame as the shaft is shorter. If either the kickstart itself or the shaft have the slightest of bends in them it will catch the frame or brake pedal. I have three B Sherpas and it catches on each of them If everything is working correctly the bikes start so easily that your heel hitting the footrest shouldn't matter, the kickstart doesn't need to rotate further than the footrest. Use the clutch to get the kickstart into a comfortable position and then fiddle with it to get the piston to TDC. Then let the kickstart up as high as is comfortable and give it a sharp push rather than kicking and thrashing at it. If everything with the engine is as it should be it should fire up with one kick. It's thrashing and kicking at it that can bend things inwards towards the frame There is no alternative lever that bends away from the frame

You have to dismantle the engine

Yes, like the first picture in Carl Ekblom's post. I forgot to link my reply to your original question. As far as I know the Indian seller doesn't have proper Sherpa tanks, only Alpina Also, there are two types of alloy tanks for later Sherpas and are different shapes. The alloy tank fitted to UK bikes from model 159 up to 199A are copies of the original fibreglass tank. The UK alloy tank originally fitted to the 199B (now reproduced by JC Fabrications - see bottom picture) and the alloy tank now available from Spain (middle picture which is the tank In Motion sell) are based on the last models plastic tank. The slope of the tank where it meets the seat is differs from early to late and the front of the seats for each were shaped to match You didn't mention which bike you have as there was also an alloy tank/seat unit fitted to the 'slimline' Sherpas in the UK from '73-'75 but that won't fit models 159 onwards and there are no replicas being made of that one. Similarly the later tanks won't fit a slimline model