Hi all

bit off a problem here,,,,,, i have a ty 250. now we have power to the end off the HT lead but no spark. this is confusing the hell out of me. Has anybody out there any idea what it may be please

Did you test or replace the 5k resistor spark plug cap?

What year of TY is it? Asking to find out if it has a magneto ignition like my old 1974 model has. I don't know if newer models have cdi/breakerless ignitions or not.

Did it just suddenly stop on you, or just won't start after sitting for awhile? Having said that, it's never a bad idea to check and clean all the ground contacts (to earth). If it has a points ignition, take the ignition side cover off and have a look under there. Sometimes condensation can be the problem there. Be sure wiring looks good, points are opening and closing, and etc.

Lemur's suggestion to check the plug cap is a good one. You can do a lot of electrical checks with a cheap DVOM (Digital Volt/Ohm Meter) on that cap, the coil, and wiring and such.

(Added after re-reading your post, Andy-Walt): I think Lemur is on to something. If you can get spark without a plug cap, a new spark plug cap may be in your future. Personally, for my bikes, I've never worried about having a resistor style cap or even resistor spark plugs in my bikes with a CDI ignition. And spark plug caps are cheap to buy and try........

Jimmie

Edited 43 minutes ago43 min by mr neutron
omitted a word.....