Aircooled Monoshocks

Hi all As anyone who has owned an early Beta knows (and has scars to prove it) the kickstart is very ordinary. Has anyone drilled and tapped the kickstart shart and fitted a later model kickstart?

I'm interested in purchasing an aftermarket repackable silencer for my TY mono (DEP, WES or those sold on FEKED). I am located in California so, as such, I'm required to run a spark arrester at any OHV park. I've been going round and round on this, trying to find a solution. I'd love to find a cone screen that will fit any of these and avoid the DIY mess I may make of a new silencer. I was also thinking of sourcing a Cobra Sparky that will fit on the back end of one of these silencers (although a bit clunky looking). I'm concerned that it may not clear the rear fender as well. Can anyone tell me the dimensions of one of these oval silencers at the back (top to bottom, s…

Hi all Anyone know the torq setting for the front sprocket nut? I have online ty350 manual which covers most of what i need for my 250, but no reference to the front sprocket at all?! It does have a table of torq settings based on nut size, but it only goes up to 20mm and that’s 130Nm!! thanks

My TK carb is just worn out on my Yamaha mono TY. I'm looking into replacing it with the old stand bye, the Mikuni VM26. I had read that Jon S. had success with these. Does anyone know the starting point jetting specs for a Mikuni VM26 for a bone stock Pinky? Thank you for your help.

Has anyone replaced or rebuilt the stock rear shock absorber on a Mecatecno Alevin?

Hi Folks, Just bought two yamaha ty 250 mono of unknown age. Bikes were bought as non running but complete. both 59N chassis id One has a steel tank with a white frame (poss originally red) it has J. Shirt on the flywheel cover and silencer, the steering lock has been cut down on that bike The other bike has a plastic tank, red frame with a dirt ground out rear link (flat where it faces rear tyre) There are differences in the frames with the red frame bike having a couple of brackets with holes on a down tube at kickstart side, the white frame bike does not have that. I could put all the best bits on one bike and keep the other for spares. I…

While pottering around on the dunes with my son, my bike, a gas gas 125 has decided to kill itself. While in top gear (and thankfully on a straight bit of beach) the throttle seemed to jam wide open, with no response from throttle, clutch or kill switch (once I`d wrestled it to a halt.) After continuing to scream it then rapidly died. And surprise surprise it isn`t keen on starting, just sounds horribly rattley on the kick start. So my questions to you clever people are What caused this,what`s the damage likely to be and once rebuilt how do I prevent it happening again? I had just filled it with fresh fuel containing 63ml of putoline. Thanks, Jac…

Hi, I have a TY250 mono with a pro monty front pipe and sammy miller back box and rebored to 261cc with wossner piston, just wondering if there is a carb upgrade from the original as can not get it to run right always running on when it gets hot tried cleaning carb out I have left jetting as it was. If there is a carb upgrade where to buy one from

I’m thinking of building a air cooled mono. I have an extra rebuildable Rotax 280 trials engine and exhaust. Just need a mono chassis. Any recommendations?

Hi just wonderd if anyone would know where to get a front disc cover for my ty mono .it's had the 80s shirty convertion at some stage .

can someone tell me where I can buy a set?

hi ....im getting a rebore on my yamaha ty 250 mono could anyone recomend what pistons are available and what modifications if any do i need to do to make it compatible....Thanks for any replies.

It´s been a while since i was here! I just finished my rebuild of my new Honda Aircooled Mono TLM 250R (1988). A quite rare Bike and it seems to be underrated in my opinion. I was looking for an air-cooled mono and wanted to have a disk brake at least on the front. And i was in the mood for a japanese bike again. A few days before christmas i bought this bike in really bad condition. Parts are not easy to find, but when you get a little creative a lot is possible. I managed to find a wössner piston of a 250 Rotax that was available in 74,50 and 75,00 sizes. The main difference was the 18mm Piston Pin and a different shape to the dome. …

When running, I've oil dripping from gear change shaft, easy fix or engine split ? Ty250s

Hi, I am having some issues setting up this air cooled mono, its recently had a full engine rebuild, I have cleaned out all the exhaust system and repacked it, i have had barrel off for inspection and this would appear to be correct, i have stripped the carb down and to be honest its very clean(original 26mm TK), it would run then suddenly stop...this faulted to the ht secondary ...replaced aok, i rode it 3/4 throttle up a long hill and then did a plug chop)nicebrown/tan colour(, the problem is lower down in carburation especially when warmed up, i believe the pilot maybe a tad weak, anyhow iset air screw to 2 out, and rode it around fine tuning on air and tickover then i…

Hi, does anyone know a good jetting starting point(main+pilot) for 26mm PWK f/side carby for a TY250 mono, Ta.

Hello It's wonderful to join you all I have a tx 240 but the disc valve came loose and jammed, I would say it's a catastrophic engine failure as the flywheel slipped, crank gears slipped, disc valve broke in 2. Flywheel previously welded on and crank taper is in bad shape. Cylinder and piston are fine and bearings all ok Where would I start looking to get a rotax 240 engine to replace my old one or part to fix her. I bought a rotax 122 engine but it would require some fabrication to work- drive sprocket won't fit its too low for the chain. We're worried about the strength of the frame if we start cutting. What alternative engines are the…

Hi, I'm considering a 1985 jap import TY 250 Mono, just wondering what peoples thoughts are on these, any pros cons or things tor look out for? This has the autolube fitted, is this system easily removable, being an import are their any specification changes to be aware / wary of? Cheers!

Hi I have a JCM 323 that I use infrequently. At the weekend it started fine on the Saturday afternoon, but at the Sunday trial nothing (although there did appear to be a week spark). I suspected the kill switch and with this disconnected it works fine. The switch was connected to the blue wire on the Motoplat ignition coil and I think it just breaks the connection. Today I have fitted the lanyard type switch from my Beta (and it worked fine there). This still does not work, but again with the blue wires just connected it fires up every time. I have put a meter across the lanyard switch and this seems to show an open circuit with the cap on and …

Simple, thanks again to thai-ty.