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Discussion Starter #1
So my problem has been that when ever i go to start the bike hot, or hot "ish". I have to give it just a bit of throttle, like 1-2%. And when it starts, have to keep it second or two at 2000rpm, otherwise it will want to stall. But cold starts are good!

Was wondering if this could be remedied with the PC3 also, like adding or subtrackting say 10% fuel at 500 rpm or so? But how do i know if its lean or rich at start up, since my lambda shows whatever it wants at start ups....

I do remember that before i put on the PC3, i tried a super lean chip on it that started it up real good when hot. Or is there some sort of start up map function that you can build on the 16M chip?
 

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That’s what the cold start lever does. Adjust the slack out of it and you should be fine.
 

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There is a compensation in the fuel map for engine temp as well as ambient temps. There is also a "start" injector duration setting that adds a bit more fuel on initial start up.

Perhaps yours is a tad too long (rich) which would make cold starts great but hot starts a bit more temperamental.

SilentService703's suggestion is the easiest "fix". Opening the throttle just a bit provides more air to lean the start mixture out.

Interestingly, more than a few Japanese brand owner manuals advise to open the throttle slightly when difficulty with hot starting occurs. So you have that going for you !!!

Adjusting your PC will affect all fueling all the time. Not a good corrective measure for your concern.
 

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Discussion Starter #4
But if i only lean the 500 to 750 rpm range? It only affects on that range.

I actually leaned the low end some more, it does get better the hot starting. Just that its hard to figure is 1% a lot or not?
 

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1% is not much....and at those rpm settings it is only starting fuel supply as idle is much higher.
 

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Good to know !!! Thanks for reporting back.
 

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Discussion Starter #9
Its been a long road to make the right maps for the engine, the 910 brutale motor with F4 airbox and exhaust has proven to be really sensitive to AF ratio, a tad rich and it just wont go! But now after weeks of mapping, its hard to fault anymore, so considering the 70 euros spent for it, its been pure gold :)

I will do a bit of a write up on this to the other section.
 

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?

Cold cranking fuel is richer than cold idle fuel.......
ViggenF4;
I'll send you about 15 base maps from a friend's ECU that he makes.......
The maps work on everything
PM me a mailing address
 

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Discussion Starter #11
It starts fine now when hot, cold starts have always been good.

But im really interested about them maps Knurl, so i will send you my email.
 

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Discussion Starter #13
Almost as fast as my previous 1000cc F4. Might even be more responsive to throttle, anyways its light years better on the bottom and midrange as an 750.

The engine is also much smoother than my 1000cc version, alltough that could be down to mapping.

Would not ride the 750 again, after riding this for the summer.
 

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I like the idea of an engine tuned for mid range much like many of the nakeds for the road. I like the look of the sports bikes though. For now the the ole 750 engine is going well on mine.
 
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