feetupfun

5 speed is standard for model 92

You didn't mention checking for: Fuel tank venting issue Fuel tap filter flow restricted Fuel hose kink Fuel hose filter restricted Fan not running Fan running too slowly Radiator airflow restricted Leaking connector carby to cylinder Air screw/idle fuel screw set incorrectly Exhaust flow restricted Is it the Sherco model with the fuel lift pump?

The usual thing with those carbies is that the needle jet wears alarmingly fast which makes it run rich just about everywhere. They also suffer from the jet needle wearing and the slide wearing and the body wearing. Have a look through the needle jet and I wouldn't be surprised if the hole is elongated rather than round. The jet sizes sound OK but you didn't mention the needle size. OKO. Keihin, Mikuni, Dell Orto all make great carbies for your bike. Bultaco with good carby and good ignition = fun times

If you become a site supporter you can post as many photos as you want

I've been using sealed bearings in motorbike wheels for many years so don't usually fit new seals but do find that with some wheels it is helpful to have something to hold the spacer in position while the axle is being inserted. If the old seal is beyond reuse on a wheel like that, I usually make a rubber disc that fits where the seal would normally go, to hold the spacer in place. PS your wheel looks excellent

I wish your model 27 was for sale in Australia

The most recent fork work I did on a Bultaco included green SKF seals with spacer rings I made from PVC electrical conduit (in a model 49 Bultaco). I wouldn't normally bother with fork seal spacer rings but the seal seller told me that the SKF fork seals are more prone to moving within the slider than other brand seals. I found the SKF seals do function exceptionally well.

The rolled over version is clearly shown in sales brochures so there should be no doubt that both versions were standard for the Cota 200

It would make it easy to ID if you post a photo of it

Those things are preload spacers. You can adjust the spring preload by fitting more or less of them

Complete bike not running. Some important parts are hard to source. Insufficient information of mechanical condition. $500 max in my world.

Are you talking about doing a wheelie or popping the front up as part of riding an obstacle?

My "original" is intended to mean the tank that came on the bike, not the first type of tank (fibreglass) fitted to model 198 and 199. Many 198 and 199 I know of have aftermarket fibreglass tanks that replaced their original plastic tanks that fell apart. I'm hoping that 199 Enduro has a fibreglass tank of some sort on their 199 and not plastic or aluminium, or the advice about epoxy lining it may cause a lot of problems

I hope you are talking about a fibreglass tank and not the plastic tank that originally came on 199s. Epoxy will not stick well to the plastic tank

The initial comment was for 1.6 thou not 16 thou

It's conventional to say "1.6 thou" because saying it that way is easier than saying "zero point zero zero one six of an inch" 1.6 thou could be written just as easily as 0.0016" but when spoken it is a different matter

If you set the tank up properly after you have done the coating, any excess will flow back out whatever hole you choose so it doesn't matter if you put too much in to start with.

Yes Forma Boulders work well for my ample calves. They do take a bit of breaking in though

Clear coat paint on rims usually gets chipped in use and then looks pretty bad. TY twinshock Yamahas had clear paint on the rims and fork sliders from new and it chipped very quickly and looked unsightly.

Both are excellent material choices for a bashplate. I'm keen to see how it ends up looking

You are very fortunate to only have those frame repairs required. The following model Alpina (137/138) was their first attempt at using a fancy alloy steel for the frame tubes and when I rebuilt my model 138, the frame was cracked in about 10 places, which I believe is a fairly common situation. It was worth rebuilding it though. The 138 is a fabulous bike to ride as I'm sure your 115 will be

Neat job. Well done. The 250s are not as sensitive to the condition of the first muffler as the 325s are for smooth running. Yes they are a mechanically noisy motor. I didn't realise quite how mechanically noisy until I watched a video clip of mine and a friend's Bultacos. Probably made worse using my phone to make the video. The late model motors are quite quiet for some reason, maybe the different finning on the head and cylinder and they also usually have fin rubbers.

electric start TRS are selling like hot cakes

As a visual reference, here are photos of a TY250 cylinder I recently had rebored and the Wossner piston that is going in it and a couple of very old original TY250 pistons. The Wossner piston ASSEMBLY is the same weight as an original TY250 piston ASSEMBLY. If you compare just the bare pistons, the Wossner piston is heavier. The Wossner wrist pin is very light.

That combination of Uni brand filter and Yamaha cage that your links bring up works great for me. The only problems I've had over the years with the standard TY250 airbox are the Yamaha brand filter element falls apart quickly and that another aftermarket brand filter was too bulky to fit inside the airbox without it touching the sides.