HELP! - wr450f problem

Can anyone tell me how to 'bench test' if a coil is working please?

I can ride the bike for about 12 miles, it runs like a clock then when it gets hot it cuts out. I leave it cool for a bit and it goes again for a short distance, etc...
reminds me of an old car when you had to let it cool if the coil was bust and then go again until it got hot.
- so I reckon it's the coil.

It's been in a bike shop and they have tested all the electrics and an alternative coil - with no fault being found - but I'm not convinced they got it hot enough to test the current coil.

Any help gratefully received - or a bike shop/expert recommendation?
(if not it's try a new coil £100!)
Cheers
Rob

Are these any good
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Cheers mate - do you reckon my diagnosis is a reasonable one?

I wouldn't like to say,but if you want I have a wr250f ,if you would like to bring yr bike to zooport ,you could try mine off my bike to see if it works,it could the spark plug cap I think there is a coil of some sort in there,they are the same part.

take a look at this link it might help

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after checking the part No. for the 250 and the 450 it looks like they are different.

thanks for the offer 'sheep' & the websites.
cheers

The coil and plug cap are both one part on the wr. Hence no plug lead.

OK thanks

rob,if you can get hold of a manual (and i don't mean a spanish waiter) there will be a section in it giving you info on how to test various leccy parts.


at a guess it does sound like coil.whip your stator cover off and check there's no nicked wires or anything.