All Activity

Rear brake : new gaskets everywhere, pads, bolts and yellow plastics

Thanks for the advice, did not think of that.

I have a recurring issue with the rear (tubed) tyre becoming partially unseated. There's no problem with getting it to seat initially - a bit of lube, inflate it to 60 or 70 psi and it pops on nicely, all the way around. The problem occurs after I deflate it to my normal pressure (4 psi) and ride it. A section of the bead slips off its seat, about 250mm in length. I can reseat it easily but when I deflate it back to riding pressure and ride the bike it happens again. The rim looks fine, as does the tyre itself - both are fairly new. Suggestions? Superglue and self-tapping screws?

Include a photo when you’ve got it back together. Best of luck!

I'd be testing the bottom end seals.

Hi, I hope some of you more knowledgeable Bultaco owners can help. i have a model 90 that has been fully rebuilt and it’s fitted with 36mm Mikuni carburetor and new electronic ignition. Its an absolute pig to start, but when started the motor sounds strong and will happily rev to 6000 and will tick over, but when riding on the road the engine runs very erratically and will not push through 5000 revs. The engine after 1-2 miles will start to misfire and run really badly. I have changed the main jet, pilot jet and needle with no joy. I now wondering if I have a dodgy ignition system ? Any advice? thanks Mark

Reassembly without the rear brake (a spacer replaces the caliper) to start the motorcycle and quickly test the clutch. It's great, it works perfectly on the first try. The clutch disengages the transmission perfectly. The fork works well. Note: To get more rebound damping, you need to loosen the center screw on the left-hand cap. The adjustment is reversed compared to many other forks.

Yes to it depends on the rules set out by the organizer, the alternative to no-stop is to time limit the section. You're lucky my wife is not checking, she watches the front wheel and if it rotates backwards even a little you just 5'd.

It is a shame you have to go through the pump issue. The 4rt was rock solid for it`s first 16 years. The pump issue has been around for almost 4 years now. Terrible mess.

We went over a decade without being able to roll back. The rules were all over the place. Some places the good riders could hop sideways and then reposition themselves. Quite silly as it was the same spot if you would have just rolled back. The world rounds did away with the no stop about 3 years ago. Most places have gone back to the roll back is legal, but if you dab going backwards it is a 5. Finally there is a push for all trials to get the same rules. Very hard for an outsider to understand our sport.

Im fairly new to trials, started in December. On one of my early events, I got penalised with a 5 for rolling backwards on a section. Not very far, maybe 10 or 12 inches. So im rather confused when I watch all the hopping about to see really good riders jumping backwards and even rolling backwards. This morning there was a clip of a rider bouncing his bike around and rolling back into a prime spot pointed out by his minder. Are there different sets of rules for club trials and national events? Im not moaning at all, just confused Cheers all

The hydraulic clutch looks very nice and soft. New ignition cover and cables heat protector.

Just a follow up. Been on my new (to me) 4rt for the last 3 weekends. Starting to feel at home on it, much more so than the Beta I had before. The bike feels heavier, but more predictable and more planted. I love the throttle response, im still a bit jerky on the clutch, but im sure I can iron that out in time. Its already on the bench for repair having fallen foul of the well known fuel pump issue, whether the seller knew this or not, or whether I've just got unlucky is still up for debate. I've got a new Quantum pump to go on and will do oil, filter, gb oil etc. Overall, really pleased with my purchase. Thanks to everyone that helped out.

I treated myself by buying all the hydraulic clutch control parts for the '94 model (the last Climber). Complete cover, hose, master cylinder. A modification that was on Tommy's official bike in '93. I was missing the gasket. That's been taken care of with a bit of gasket paper and 15 minutes!

Thanks ALL - I ordered the lower leg on EBay - I can always repair it later if needed. $115 seems safe and it looks like new, just like my current forks. All parts ordered - seat from Spain - can't wait to put it all back togegether.

That would be affordable if you are the guy doing the machine work and you have all the equipment already.

If the bores are oval, you can have them machined to take modern Teflon coated bushings, or bronze. But, it would be much easier to find a replacement.

I remade the end piece for the swingarm pivot. It was fitted with an M14x1.50 thread and glued loctite 638. The original one was cracked. I had no experience with threading and tapping on a lathe. The result is perfect.

Hi i am trying to get details to register this bike in Uk but not having much luck tracking down. Can anyone give me any guidance on how to get paperwork? i believe its a 1977 manufacture. The bike frame has a stamp FANTIC TX 250 GM 6992 OM *0008980* or could be * 0006980*

I'm waiting for a used 4RT top triple clamp for 22mm handlebars. It's lighter and also moves the handlebars forward, which is what I'm looking for to modernize the stock, slightly chopper-like geometry without compromising the look. I have a few other bits and pieces to add to save even more weight (I expect to save around 400-500 grams). I'm going to machine an alloy swingarm pivot. I'll take this opportunity to remove the engine and take off the extra base gasket.

The fork is finally finished! I replaced the hydraulic part, which was completely wrecked. You can see the heat marks I made trying to reshape it... but the shaft and its guide bushing were shot. So, I found a suitable part from an earlier model year. There are a few differences, including the end stop, but that's actually a good thing because this assembly avoids a worn-out foam buffer in favor of a more durable rubber one. I adapted a brake hose guide. It's clean and doesn't rub anywhere.

https://www.amazon.com/-/es/Montesa-Scorpion-Vintage-Manual-Original/dp/B091G4YRW8

Stickers in progress.

Hi, I'm running a 24mm OKO from Mid Atlantic (so a genuine one) junked the air box so using a foam pod filter and alloy exhaust with no back muffler. Pilot is #42 Main is #102.