Very Hard to start when warm.

dragbike1300 · Post by **dragbike1300** » Thu Sep 14, 2006 5:39 pm

My bike is almost impossible to start when it's warm. When I first start it when its cold, it starts right up. Maybe voltage problems becouse the battery drops pretty low when trying to crank.

2003 Suzuki Hayabusa Turbocharged 1300cc's (Drag Bike)
MSII v2.3
MSD MC4 Ignition
Inovate LC-1
(4) 750cc High Impediance Injectors
9:1 compression

Can anyone help?

Bernard Fife · Post by **Bernard Fife** » Thu Sep 14, 2006 5:44 pm

dragbike1300,

Have you adjusted the hot cranking pulse width? In general, you need to go low on this.

For example, if you try setting it by turning the warmed-up engine on in the driveway, you will get an acceptable setting. But when you come screaming in after a run, and then shut the engine down and try to restart it a few minutes later, the engine likely won't start. It will often need to be a few tenths to a half millisecond less pulse width than what you can use with the 'unstressed' hot cranking pulse width.

Lance.

Bernard Fife · Post by **Bernard Fife** » Thu Sep 14, 2006 5:46 pm

Oh, and please reduce the size of your avatar, the maximum we allow is 80x80 pixels. This is so that avatars do not obscure the useful content of a thread.

Lance.

dragbike1300 · Post by **dragbike1300** » Thu Sep 14, 2006 5:50 pm

Sorry about the Avatar. I though it would auto adjust.

Bernard Fife · Post by **Bernard Fife** » Thu Sep 14, 2006 5:56 pm

Sorry about the Avatar. I though it would auto adjust.

dragbike,

Yeah, I thought it was something like that.

The hot start tuning can be a bit tricky. It helps to keep the prime pulse short (so the engine doesn't flood). In the 2.36 code, the prime pulse isn't dependent on temperature, and at high engine temperatures it can evaporate quickly, leading to a flooded engine. I generally try to keep the prime pulse under 3.0 milliseconds, ideally less.

Later versions of the code (the soon to be released 2.6, for example) have additional controls for hot start - things like a separately settable hot prime pulse width, and hot ASE settings.

If you want to try those now, they are in the code in the beta section.

Lance.

dragbike1300 · Post by **dragbike1300** » Fri Sep 15, 2006 9:59 am

I will try setting the hot (160 degree) lower. It's at 0.5 ms currently. The prime pulse is at 1.0 ms. I will also lower it.

Another question-Can I change the temps on the Warmup Wizard?

Example: My bike never sees 160 degrees. These numbers in Megatune are useless to me. My bike at cranking will see about 110-120 degrees max.

Thanks alot.

FiatFreak · Post by **FiatFreak** » Fri Sep 15, 2006 4:05 pm

In the latest beta code you can change the temp values if you go to Tables, and then Temperature Table Values. I don't think this menu was there in official releases, but I can't remember for sure.

-Patrick-

dragbike1300 · Post by **dragbike1300** » Fri Sep 15, 2006 7:01 pm

Thanks.

I will check out the newer version.