went out for the day yest, all ok however developed a problem starting, so far only happened when hot/warm starting, haven't checked anything yet, just doing some homework to see if theres any known issues cold start fine started playing up after fuel stop spent few hours at a bike show, cooled right down, started fine way back, tea an fuel stops were a problem deffo seems temp related and when it does eventually fire getting a good cloud of black smoke out of rear rides fine doesn't seem boggy or over fueling on the move, fuel amout cost/mileage seems ok does seem to be purely overfuelling on initial hot start any known problems at all ? pumps, regulators, relays, injectors ? thank you very much for any help
My first thought would the coolant temperature sensor. These are pretty cheap and are known to fail. If the sensor tells the ECU that the coolant is colder than it really is then the ECU will richen the mixture. Maybe not enough to affect normal riding but enough to affect hot starting. When cold it needs richening anyway.
Try cleaning the temp senors contacts first, and the thread faces(metal to metal). I had a dodgy temp sensor, speny 50 quid on a new 1 and it was only the mating faces that made a poor contact. Quick wire brush and ok. Worth a try if it dont cost anything.
Black smoke? Over fuelling when warm maybe, temp sensor related? I was thinking a tank vacuum, but you said you had just refuelled so will have opened the filler
thank you very much everybody much appreciated recent rebuild, temp sensors are clean, contacts are clean [good call tho, thank you] this issue id say at mo until I get a chance to plug my gauges in is massively rich on warm start up im thinking, ecu temp sensor fault poss reg/relay fault or possible when I shimmed it I went a touch tight an now shes nicely bedded in since rebuild its poss when its warm im losing compression, however id say fault started to quickly and I haven't lost noticeable performance on the move only time its a noticeable problem is hot starting gonna order a temp sensor an poss a relay cost dependant, even if mine are ok now [haven't checked yet] I don't recon itll hurt having spares in the workshop for the future
If its running very lean ie engine mods, air leaks, it can become hard to re start when toasty. Jusy saying.
hmmmm yeah im not disagreeing at all, however 5k since rebuild an alls been well until one day after a fuel stop is hard to start an chucks out good black smoke black smoke to me is saying overfuelling and the timing says a fault has jus occurred, if the hard to start thing it was because of being lean [which I think it possibly is generally] I think it would've been like it since rebuild and she has been good as gold until mid day sunday
Just referring to @Derek 's post #3 above - coolant temp sensor. Could this be linked to the problem you have "get's toasty in traffic". Perhaps the coolant sensor is the dodgy bit, giving a false reading to your temp gauge and causing the starting problems when hot now as it deteriorates further?
update for anyone searching for answers sorted in this instance it appears to be my fault ! over winter I replaced plastic fuel tank connectors for metal ones and rehosed the fuel system [h cyl inj o/e feed had evidence of a kink in it] I was supplied 'efi' rated hose from a motor factors i run it up to temp to replicate the fault, got it to do it, stripped it down an noticed the front injector was damp, refitted tank propped it up a sniff an used my tv on a bendy stick thing ? forgot its proper name primed it an saw fuel squirting from injector/hose connection straight into the throttle body ! on investigation r6 fuel hose is rated for 50psi and 100*c it had gone a touch soft for my liking [heat id guess] wasn't leaking during running only ign on priming rehosed it all, jobs a good un, i will order a higher rated r9 hose redo it all an should be a done deal thank you very much people for help advice or even jus humouring me, much appreciated i know this prob wont be relevant to most but maybe one day it may help somebody out
