Hot Engine wont start!!??

[Acidicall]

Hello guys/ girls, ok so the problem i have is that the engine starts no problem when cold but when it gets hot, (close to the fan cutting in) the engine wont even crank over. It seems that the hotter it gets the harder it is. When i stop for fuel that seems to be enough time for the bike to cool down enough for me to start it (just), but when i turn the engine off at lights i have to wait 3-4 mins before i can start the bike!! So is it the starter motor? temp sensor?

Any help will be good!! Thanks all

[Wicky]

Check the starter motor connector under the rubber hood for corrosion.

[Miztaziggy]

Do you have manual CCTs?

If so, maybe they're too tight, so when the engine gets hot, they're putting too much force on the cam chains and stopping it from turning over?

[Acidicall]

No i dont have manual tensioners yet. The carbs have been cleaned and a dyno fitted and that all works nice (floats all set properly etc). The values have also been done last year and havent had a problem ( only done 2000 miles since).

As for the starter connections i havent looked at it but i replaced the rubber protector last year as well and the bike doesnt go out in the rain, so i dont thin k it would be that. but i will check.

[Miztaziggy]

Hmm..

Seems odd that it won't even try to turn over when it's hot. Sounds like something maybe expands and tightens up stopping it turning. If it's not tensioners and you're confident the engine is OK then maybe it's the starter motor itself that's gone...somehow getting hot and losing the ability to turn.

[AMCQ46]

my bike did this 2 or 3times about 3yrs ago and I never pin pointed the exact problem as it wouldn't happen every time, but it was clearly electrical.

so I stripped the starter motor bolt connector, plus cleaned all the ground connectors and the battery connections and recharged the battery............its been OK since

[Acidicall]

Ok thanks all I will have a look at the starter. Strip it down and so if I can see anything.

[VTRDark]

(floats all set properly etc)

Floats are non adjustable. They either work or they don't.

My first thought was like ziggy's, something expanding causing it to slow it cranking over. I'd start with the starter motor but also don't forget the starter switch itself and the wire from the switch to the starter relay. This may be a bit temperamental. Is the battery and charging system all good?

(:-})

[Acidicall]

All new electrical system. that went last year. ok i stripped the starter and the previous owner must have stripped it and broke it and bodged it back together. moisture must have got in and seized one of the postive bushes. so it wasnt touching the amuture and thats why its been getting worse. not sure why it is worse when its hot. Electrictry doesnt pass through hot objects as well??! dont know. but got a new starter motor on order so will see when thats fitted.

[darkember]

Sort you CCT's out if they are still stock or you may well be sorry in the future. Kind word of advice.

[tony.mon]

It may be that the starter motor's insulating washers are fitted incorrectly or are failing.
This allows the insulated bolt to touch the casing- and when it's hot it can expand and make more of a contact.

[Acidicall]

Ok so put a new starter and fixed all the problems. Took the old one apart to see what was wrong with it. Previous owner must have stripped it down and broken something as he tried gluing the thing back together. Water must have got in as the "glue" is not as good as a rubber seal and the positive bushes were seized in place. So that's why it was getting worse. Silly bast**d

Thanks for your help guys and yes I will do the CCT S when I find some time.