sherpa325

If the chain oiler is standard factory fitted then the swinging arm will not fit your bike. They were fitted to the slimline models from 1972 through to 1974 and don't include a space in the centre for the rear engine mount bracket.

I had a brand new Piuma back in 1984 and the marzocchi rear shocks were quite stiff and had a lot of damping. I never used them after one practice session and replaced them with Gas Girlings, which were the best shocks available at the time and a huge improvement. I would suggest using the lightest oil in them 2.5w and back in the day when I was modifying shocks I just filled the tube the piston runs in and then put the piston in with any excess being pushed out. Cheers Greg

That's not the only thing that isn't working and using your mates wife for your avatar, what can I say

They are a pretty simple motor and will run even when the ignition timing is a fair way off. It can be a little tedious to get it set correctly at 2.7 - 2.9 . I have found the best way to do it is to set the points on the low side of the allowable gap and then rotate the backing plate by loosening the three screws that hold it in place to achieve the correct timing, and it's probably going to take a couple of goes to get it right. Cheers Greg

I reckon 2009 was probably the last time I saw you ride your Hontaco or was that Bulda

With the Elf oil I can find neutral easily and the clutch does disengage, however that's not the case with ATF

The oil does make a difference and the lighter the oil the better. I use ELF htx 740 , another good light oil is GRO Gear Extreme 75W. There are ways to adjust the clutch inside the case, but I would change the oil first and see if that works. Cheers Greg

Not sure why everyone seems to overthink this issue, C3 bearings are standard and don't cause any problems that I am aware of, so why fix something that isn't broken it's a trials motor after all not a motocrosser or road racer where it's getting flogged to death

Most of my riding buddies and myself included all put a smaller front sprocket on them to slow them, 11T is standard but they make a 10 and a 9. I use the 10 and it makes a big difference, also makes second and third gears much more usable as well

As has been said you definitely need the woodruff key to locate the flywheel correctly, maybe you have installed the backing plate incorrectly , ie out by one or two screws or 120 degrees. It can be mounted in three different positions and from memory the wires exit on the left hand side and the 'coil' is vertical on the left hand side. Please correct me if I am wrong but that's how I remember it. Cheers Greg

Just a thought,check the ignition cover and make sure the operating arm that has the spline on it is installed correctly , it is possible to let the arm, in the case, rotate around so that it doesn't push the clutch rod in. I fixed a friends bike the other day where this had happened, he had taken the horizontal lever arm off in order to put a longer one on, to get a lighter action, and the vertical operating arm in the case had rotated out of position.

They used to be advertised as the lightest production wheel in the world

All Sherpa T 250 325 340 models have 60mm strokes

I think you are worrying about nothing here as every year the bikes were better, with a wider spread of more usable power. I wouldn't read too much into the graphs published in the manuals as for example the M92 325 and the M125 325 have the same graphs published in their respective manuals but the M125 has a larger 27mm carb in place of the M92 25mm and is a much better motor. In 1975 the 250 was reduced in size to 238cc to allow for cheaper registration in Europe and I wouldn't be surprised if the factory downgraded the power output 'on paper' to assist in this cheaper registration process, just a thought anyway! Cheers Greg

There are two types of that style of airbox. The 325/350 version is the better in my opinion as the side panels are slightly concave, bent inwards, and less likely to be damaged by your boots rubbing on them. The 250 version has slightly convex side panels and is more prone to wear from your boots. It's very difficult to pick up which is which when looking at photos but all the smaller capacity bikes I have seen in the flesh have the 250 style airbox, whereas the 'inmotion' one appears to be the more desirable 325 style. Cheers Greg

This can occur on GasGas bikes as well and if it can't be cured by winding the air screw in a little, people generally go to a one size bigger pilot jet or a no3 slide or lift the needle. All have a slightly different effect and it seems to be a bit of trial and error as to what works for you. Also its important to do this after the bike has been decoked as carbon deposits on the head and piston can cause an increase in compression and add to the problem

No, Sherpas only came with one plug hole standard. The only ones I saw that had an additional hole were for a de compressor, which supposedly made the bike easier to start and were used going downhill, to stop stalling,and were owner fitted not standard. I have never heard of using a plug to start and then another one for running and I can't imagine a second plug that is not being used is going to fire when the working plug gives in. The non working plug would be covered in all the combustion by products that are in the combustion chamber and it would be doubtful that it would be in working order. Cheers Greg

Thanks, I assume you have now seen it!

I was pretty sure Trial 2 was changed to 300cc 2T

Google the site 'In Motion' they sell all sorts of parts for Bultacos including electronic ignitions that use the original flywheel. They are very professional and easy to deal with. Cheers Greg

I would check the wheel spacer as these are not standard and were used to replace the speedo. Mine are 33mm but I have seen quite a few variations, smaller and bigger, and yours does look a little small to me, but difficult to tell. Any reasonable fabrication shop should be able to straighten it, after all its just steel, which can be heated straightened, welded all quite easily. They did bend back in the day and we used to straighten them in the bike. Cheers Greg

Gasgas should make Cabestany an offer and get him out of retirement!

Exhaust pipe has water in it maybe!

The M80 wouldn't look too bad with the later 'boomerang' or 'clubfoot' - which both perform better than the original triangular one. I don't recall anyone using the original back in the day or even now but that is not to say it couldn't be modified to give a nice note and decent performance, however the volume looks to be way smaller than the current setups and it is impossible to make it bigger. I guess you could try opening up all the baffles as well as using larger diameter inlet and exit tubes as has been suggested.

I would suggest you try and find a complete later model bike as it is getting more difficult to find missing parts these days and the cost of these parts has increased accordingly. Any of the bikes you have chosen will do the job even though they are all different to ride with each having their own personalities. I would personally choose a Bultaco because they have the best parts availability and they are relatively bullet proof and easy to work on. I quite like Montesas but they have some issues when you come to work on the engine, I have only ridden a couple of Ossas back in the day but they also felt fine and regarding the Yamaha, they sold heaps around the world and they were very competitive and reliable with good brakes. I would also recommend you think seriously before modifying any of these bikes as they were all developed by riders who were competing in the World Championship at the time and in particular the Spanish bikes were very close to what the factory riders rode the year before. Enjoy restoring the bike, make sure you put a good set of shocks on the back and a good set of tires as well as a set of late model wide footpegs and enjoy the experience