Restored a TY80 for my son last winter. Recently, it has developed a puzzling little problem. It starts up and runs fine when cold, but after it is warmed up, if it is shut off for a short break (or he stalls), it will not fire back up again. Kicking, choke, no choke, bump-starting, throttle, no throttle, nothing works! After sitting for a half an hour or so however, it will then fire right back up again. Any thoughts on what I should be looking at first? I was wondering about the condenser; if bad, would it create a symptom like that? One other question, do you know what the proper torque setting is for the cylinder head nuts? I'm thinking maybe loose head? According to the manual they should be at 1 m/kg which converts to about 7.23 ft/lbs (right?). That seems awfully low to me, isn't it? Am I converting correctly? What do you guys tighten to?

Any help with this would be greatly appreciated. Thanks, Matthew

it could be a number of things chap. i would start by changeing the spark plug. although i had a problem same as this a few years ago the bike would allways start when cold but never warm i changed everthing and was ready for giving up when someone told me to check the reed valve to my suprise it was stuck open (had bent some how) so i staightend her up and she run fine. just a thought

Could well b the condensor, cheap to change and rule out.

I hab exactly that problem on one of my 250's.Changed the coil same,changed the condesor and the points no trouble at all.So get her a new condesor and a new pair of points and it will work again.

Chrs:Mike

Sounds like a dud source coil in magneto to me, try the points & condenser first then you'll need to have some readings done if not the cause

Interesting responses, and I thank you all. I have not had time to try replacing the condenser that I got (points not even a year old) yet but I wanted to direct your attention to some supporting comments I found from another thread on this same site. Look at comments #10 & 11 in the "Twinshock" section under the sub topic "Problems with Amal Carb?" It is almost word for word.

I would say as you have mentioned, try the carb as if it starts when cold the mixture could be rich so it would start fine,stall the bike when its hot and then trying to start a hot engine with like its got the choke on. Just a thought, it could be whats been mentioned also.