So for the last couple months I can start my 450 90% of the time if it has been sitting in the garage. If I take it to the track it will always start the first time, ride a moto. Maybe it starts again and i do a 2nd moto, but its over after that and end up draining battery cranking it.
Tried disconnecting map switch/kill switch, makes no difference. Thought it was fauling out plug or flooding but there is never gas on the plug and I have replaced it to no avail, no gas in oil.
Next thing I'll try is pulling the fuel pump filter and seeing if it plugged up with old varnished gas or something? It did sit in a barn in oklahoma for like 9 months or more.
Any other ideas? Really want to get rid of this bike but i cant sell it like this.
*Bike has less than 5 hrs of run time, actually a 2022 rs model
I pulled the fuel pump filter and lightly blew back through it with compressed air, although it didn't appear to be clogged.
Now it seems to work somewhat reliably? Reluctant to start once its hot but fires up within 5 minutes, I usually wait 30 seconds to a minite between attempts.
So this all points to the filter being the culprit? Could it have been clogged by some kind of microscopic particles of old fuel? Its a 70$ part so im not just gonna buy it on a whim. The bike has always ran great when its running and hasnt ever cut out or felt like its starving for fuel.
Its almost 50 degrees colder now on oklahoma, Im thinking this could be the reasom why its working all of a sudden. Maybe bad MAP sensor? Im gonna check TPS voltage next
I would check TPS voltage like you mentioned. Make sure it was set correctly out the door in the first place. I’ve seen bikes that were nowhere near where they were supposed to be.
It could also be a bad sensor. It wouldn’t hurt to check that while you’re at it.
I would rule valves out as you’re only having the starting issue when it’s hot after the first initial start. Will be interested in seeing what the problem ends up being.
I hope that you’re able to figure it out. It very well could’ve been something in the fuel pump filter causing the issue seeing that it has improved since blowing the filter out.
I’ll be following to see the outcome. Good luck!
A can of starting fluid should almost be the first troubleshooting step on an EFI bike every time. It allows you to manually fuel the bike so you will immediately know if it's a lack of fuel problem. When the bike won't start, remove the filter and spray starting fluid into the intake as you crank. If you can get it to fire on starting fluid, you know something is causing a lack of fuel.
It could be the Coolant temp sensor or Intake Air temp sensor is whacked. That would explain why it starts when cold but not when hot. Sensor is failing to properly compensate for temperature and compensate fuel. On some bikes the IAT can get covered with filter oil and act up. Make sure that is clean.
I doubt it's valves. One, too low hours for that. Two, valves usually cause hard starting when cold but then not so much once warmed up.
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