Hi everyone, new member here. I hope someone can give me some advice, I have a XJ750 seca and the last time I used it it let me down. It was a very hot day 30 degrees or so and she seemed to be running quite hot, she then started to missfire badly on both cylinders and was down to 5-10mph, I let it cool down for a while and she run fine for about half a mile before misfiring again I got home the last 20mls at 10mph. I am just recovering from a bad accident on my CX and can`t ride a solo again so I want to put a sidecar on the XJ but need to sort this problem out before i go down that road. Anyone come across this problem and can put me on the right track, thanks

brassnobs

Hi there,

sounds very much like one of your ignition coils is breaking down when hot so you are loseing power on two cylinders thats why your performance is so bad ! next time this happens see which two exhaust pipes cool down and which two are still hot this should give you an indication of which coil is duff?

Hope this helps

Regards

Bill

Hi Bill, thanks for the reply. Have had a couple of coils from a xj550 which should fit so I will try them, fingers crossed

Tom

By the way, I should have said on all cylinders (must be to used to riding the CX) but still could be the coils I suppose so will change both

When i got my XJ650 it used to run great for about a mile then cut dead, would not start until it cooled down a bit then you could go another mile or so and it would happen again. Problem was the TCI unit, once replaced no more problem, if it was starting to break down it could give the symptoms you are getting and a replacement is quite cheap of ebay. The only way i know of checking this is to replace the unit, cant think of anything else that would affect both coils at the same time.

This guy had a similar problem

http://members.tripod.com/dave_jack/id41.htm

You could also check the fuse box, if its original it will have the old glass type fuses and as they get old they give all kinds of problems, most people replace them with newer type blade fuse box.

Thanks Dave, yeah that seems more likely than both coils going at once. Will renew it and carry a couple of spare coils just to be on the safe side.