tdm900

Is it when the fan cuts in? I had a very similar problem with a rotax aprilia, whenever the fan started up it seemed to steal some power from the ignition circuit for some reason. In the end I ended up wiring the fan into lighting circuit, that cured the problem.

I'm thinking of freshening up my tyz with a new set of rings. Have any of you done this recently? The reason I ask is the cost of the bits, especially if when I pull it down I find it needs a piston. I am assuming the bits fron the scorpa sy will be a direct fit, but how does their price compare to the tyz at : piston=

Dear all (sr34, Woody and Outlaw) thanks for your support and suggestions. Top of the class today is Outlaw Dave. I drained quite a bit of oil stained fuel out of the crankcase when I up-ended the bike and then it started second kick afterwards. I must admit to leaning towards the woodruff key myself, especially with the backfiring. But, there you are, you learn something new everyday ! cheers

Seriously, can you get a crankcase full of fuel???

After last Sunday's trial I brought the bike home and washed with hosepipe as usual. Went to try and start as I usually do to dry things off and it and it just wouldn't. So I tried the standard cure of spraying everything with WD40 but to no avail. Then I noticed I'd transported it home with the fuel on. So I decided to leave it a couple of days to dry out internaly, just in case I had flooded it. Fast forward to Friday, took the plug out. black and wet, that's the problem then. Dried the plug out on the gas hob, checked for a spark, not brilliant but I thought it would do. No way. all it would do is backfire and scare the **** out of the dog !! Then noticed carb was flooding a bit, so took that off, gave it a dam good clean, float working well after reassembly, tried again, still won't start, I'm starting to get p****d off. So today, took carb off again, good clean, reassembled and installed, bought new plug (spark looked weaker if anything) still won't start, Checked wiring. disconnected kill switch, reinstalled ht cap with silicone grease. cleaned earth point on ht coil. even took sumpgaurd and flywheel cover off to check for any evidence of rotor displacement (none apparent), guess what, still won't start, still backfiring though. Any ideas or suggestions really would be appreciated. I've got a multimeter so if anyone could advise how to check the various components of the ignition system that would br brill'. there appears to be a lot of unecessary wiring left on the bike, I guess after the lights have been taken off, can this be "rationalised" ?

piston - http://www.jkhirst.co.uk/acatalog/Pistons_Rings_Pins.html gaskets - http://www.jkhirst.co.uk/acatalog/Gaskets.html not cheap though !!

Woody seems to be the font of all tyz knowledge on this forum, are you reading this ? Have you any idea?

you can get a copy of the workshop manual for the scorpa 250 (same engine) ........... http://www.scorpaaustralia.com/Tech.html This contains all the oil details etc if you PM me with your email address I can send you a copy (3.12 meg)

Try JK Hirst of Bradford http://www.jkhirst.co.uk/acatalog/store.html or Nigel Birkett's sorry don't have web address- you could google it

I recently bought a cracking TYZ 250 and there is one thing that is intriguing me. It has got the number "18" stamped into the top of the headstock, just in front of the radiator cap. Does anyone know what it signifies, if anything?

Thanks for the positive responses guys, thing is, I'm not without a certain amount of bulk or girth nowadays, the the concept of having an easily managed and maneuverable modern bike is largely irrelevant You may have heard of the expression " a pea on a drum", well putting my body on a modern trials iron could be described as " a drum on a pea"

Gving some thought to returning to the trials scene. I started a long time ago - 27 years to be precise - and gave up when the born again road bike bug caught me. I have been attending trials over the last year as either a spectator of observer and although I enjoyed it. it's not the same as actually competing. Thing is, if I'm going to take trialsing up again, i don't knpw what type of bike to buy. I don't have a wadge of money ( kids at uni, etc) but I'm not going to skimp and buy a nail. I quite fancy getting myself a twinshock fatic or the like and then compete on the clubmas course, but will I end up frustrated with the bike ?? Also it sems to me that the twin shock scene is becoming a tad overpriced ( thanks perhaps to evil-bay). So should I drag my old, fat body back into trials and what bike should I buy ?