[Oscargffg]

My 98 1200 sporty runs when cold but looses spark when it warms up! I mean no spark is it the coil or something else?

[PeterHD13]

Yeah a lot of times it can be a coil but check the connections are clean first undo the nuts on the coil and clean the terminal ends and electrical contacts. Also check and clean inside the High tension spark plug lead compartments.

If you get a clymer manual or haines etc there are tests you can do on the coil to make sure it's OK. Or just take the coil to to shop to test it or get a spare off someone to try and see if that fixes it.

Check you spark plugs too as they can go the same way when they get hot. Take them both out. Clean them up attach them to the plug ends and sit them on the head hold one at a time with a set of insulated pliers with the base of the plug against the head or earth, turn on the ignition and kick the bike over and see if you get a strong blue/white spark. If it's weak yellow try a new plug. If it's still no good it may be the coil leads, coil, or the pick up on the timing side. Electronic ignition modules can go the same way when they get hot/ vibration. There are set tests which aren't too hard if you have a volt/ohmeter cheap digital one, that is set out in the manual. I figured it out it's not too hard. Just putting a probe in the right spot and reading values.

I found a broken ignition wire on my feed to my ignition unit near the plug connector for the cone timing sensor . Check continuity. There only very fine wire and if someone pulls on them near the plug connector they can snap or go intermittent. So I cut off the stock connector and Double wired mine through a six pin connector.

The Sensor inside the cone can go too but there are tests for that as well. If it is your ignition module.sensor you'll have to buy a new one . I found some trick systems on Ebay that sit the whole system inside the timing cone miniturised with adjustmet tabs for around $250 to $400. I was thinking of buying one when I save up they even have a KIcker/ electric setting. Otherwise there's OEM new or second hand, may as well upgrade Screamin Eagle etc.