TE449 warm starting problem

OK chaps,here's another brain teaser from this little fair isle(UK).
As the title suggests,starting from cold no problem,starting when hot no problem,but leave it for more than a couple of minutes and it takes a fair bit of turning over before it fires.it's fitted with supplied race can,it's on race map and exhaust sensor is removed,I've also changed water temp sensor.
I have been told that people have fitted an extra earth wire(s) on bikes with similar problem,is this the solution?,if so,where and how are they fitted?
Any help welcome.

Mick

May be injector leaking? Or idle too low.

It's a known issue with no real world solution thus far. I will look into manufacturing a part I have designed to fix this issue.

Mull, does it make a difference with or without a little throttle added while cranking?

The only time my own bike is a little reluctant to fire is after a hot stall.
That is if caught out by say a rock ledge/log or something or a little too abrupt with the clutch & stall the engine.
In this instance, winding without throttle takes a couple of tries, but winding over with a little throttle (1/8 -1/4) always has it fire straight up.

At all other times it fires first wind, hot or cold, no throttle.
It may be worth looking at the air-temp sensor if you have already done the coolant sensor....

There was also 1 dude who has separated the crank pick-up wires from the alternator wiring.
I've not tried it, but the idea has merit. It is possible in theroy that the a/c wires may induce a signal, or at least disrupt the pickup signal.
Resistance increases with heat, so again it's possible to have it get worse when hot.

It may not improve it, but is simple & free to try & would have no negatives in doing it. Basically worth a shot.

I used to have the same problem along with the stalling . But ever since the dealer repositioned the TPS And turned up the idle I haven't had a stall or a hard start ...

Turn your idle screw out 1/4 turn (counter clockwise) and see if it gets better. If not, try another 1/4 turn out.

For me, cold starts have always been perfect, but hot starts required a bit of throttle as DM stated above (1/8 or so). Now I don't touch the throttle. I think I am 1/2 turn out further vs. stock. People have a wide variety of idle screw settings so don't take it for gospel, but mine is 2 3/4 out from fully closed.

Correct. Adding more idle speed also adds more air, so leaner at idle with no other adjustments.

"warm" starts seem to be a problem on this bike. It is too rich. I used PCV to lean out in the cranking RPMS and it starts better

EarthX battery, increase idle speed (to around 2k-2100 rpm), lean out cranking RPM's with Power Commander <-- These changes helped my hard starts significantly

Sorry for late response guys,I've been away for a couple of days.
Thanks for all the advise on this issue,I will try them one by one to see which one does the trick and get back to you.

Well I tried the easy stuff for last weekend,ie quarter turn on tickover and a bit of throttle,and while this was a bit hit and miss it was still better than before and something I think I can live with.....of course the other thing to do is just not stop riding all day!!!....downside of increased tickover seemed to be less engine braking which I found out on first rocky downhill section!!so that will be going back to standard.

The engine is too rich upon start up and needs a hot-start button only found on the TC449's. Tuning this with a pcv seems to be the current solution.

It is a real shame the factory ECU isn't set up correctly to use the sensors it has, isn't it?

There's an Air temp sensor, Coolant sensor & Map sensor which, if all used & set up correctly,
would negate the need for adding for adding any extra air.
If they were used, the system would know the engine coolant & inlet air were hot & what the current atmospheric pressure was.
The mapping should be set to lean the mix accordingly, but obviously it isn't.

Lucky the PCV can do this.

It's a shame we can't even work on the oem TC and TXC ecu's which is a real issue. The pcv allows you to set timers and temperature I think. The hot start button is perfect, but Husky purposely made it so that you couldn't add the TC hot start button.

It would be good and not that hard to utilize the PCV's temperature input if we knew the volts to temperature values for the stock sensor. I bet Tinken could reverse engineer the values. Or maybe I should go reverse psychology and say I bet he couldn't

Hahaha. The shop's closed til Monday, knock your self out.

Jump out clutch switch. My bike turns over much faster without clutch pulled in and starts great now.
I am sure Tinken can tell me why?

Yes, from a different tack, my earlier non clutch switch bike started HEAPS easier hot with the lithium battery fitted.

The difference in cranking speed hot or cold is very noticeable on my bike. Bike starts faster hot or cold,
something really slows it down with clutch in.