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EFI cold start issues

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Still fighting with my 09 450 RMZ (bought new, 17 hours on it now)

Engine cold (as cold as it can be in FL at this time of the year), with or without choke, it's taking dozens (when not more) of kicks to get it started, to stall a few seconds after

It's doing that 3 or 4 times and finally starts and stays at idle

This pattern has been going on and on every WE and it's just taking more kicks now

Engine is running OK after that, and starting when warm is a 1-3 kicks deal

Plug replaced, valves in spec, clean air filter each ride and very slow vet C practicing only on it....

It's getting worse each time now and I'm on the edge of getting :foul:big time

I don't want (yet?) to splurge more $$ at the dealer on a new machine that's not even close to be abused.

This is not a normal operation for a fancy EFI engine and I never had this kind of problem on a dirt bike

I guess that I joined the league of happy consumers who get stuck with an expensive toy that need computer, trained tech and much $$ when things go wrong.

If I can't get that thing running (trying to work with a friend/tech who just started his own business but doesn't have yet the EFI diag tools), I will go back to a 2 stroke. I guess I should have kept my 250 SX

I didn't buy because of the EFI, just wanted to give again a shot at a thumper since it's easier to ride and I couldn't get a decent price on a KTM. I just hoped that EFI was dialed in after several years (I think suzuki brought it first on the 450 quad)

Sorry guys but I had to vent.

That being said, anybody with same experience / advice ?

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since the bike is efi and is full of electronics the bike needs basically about 5-10 nice easy kicks to get the fuel pressure built up and charge up the electronics of the bike. after that the bike should start in a kick or 2 and should continue to start like that the rest of the day. but once the bike sits a few hours or a day u will have to do the same thing over again

hope this helps

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done this since new?


This symptom started after 5 hours roughly

Got some luck and very good friends who had the bike checked at a dealer with the SDS and everything checked good.

TPS/capacitor/wires/fuel pump/etc.. checked. Idle re-adjusted (was only a bit off)

It seems worse that the weather is really hot now

I was told is that RMZ are coming rich from the factory and I can tell that the inside of the silencer tip is blackish color. Was told also that this condition could create this problem

what is annoying is that once the engine is warm, it's running perfectly and hot start are easy too

Only start/stall a few times when cold. Exhaust is stock

Could a map adjustment with the Yoshi box help?

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