Going back on 2 step at end of track ? Ideas ?

jeffmarsh750 · Post by **jeffmarsh750** » Tue Jun 14, 2016 2:40 pm

This is on one of the carbed bikes I put together last year. For some reason this year it started dropping cylinder 2 at end of track. It is waste spark and we have spent a ton of time chasing this new issue. I think I have seen similar results on my other bikes as they would re-start the nitrous timer and sometimes the boost timer but never triggered the rev limit and retard from 2 step. You can see in the very end of the run the timing go back to 25 degrees a few times. It is nosing over in 4th gear too and really bad in 5th if you stay in it. To listen to it go down the track it sounds like its on a rev limit. The other bikes I added a VSS input and made the launch innactive above 5mph but it didn't help this one, as it also has a speed sensor problem. This is kind of a band aid even for my bike and if sensor fails it may mess up the run.
Any suggestions would help. Thanks, Jeff

Post by **jsmcortina** » Tue Jun 14, 2016 2:56 pm

Please attach a datalog of the problem.

James

jeffmarsh750 · Post by **jeffmarsh750** » Tue Jun 14, 2016 3:29 pm

Woops !
Accidently added a 2014 msq. Here is the log.

jeffmarsh750 · Post by **jeffmarsh750** » Wed Jun 15, 2016 12:51 pm

Hay James, could you check out the log when you get a second ? Do you think it's possible I need to add a pull up to the launch in circuit ? Maybe it's seeing a false edge trigger on the digital in. Thanks, Jeff.

jeffmarsh750 · Post by **jeffmarsh750** » Thu Jun 16, 2016 6:13 pm

Need some Ideas here if possible ??? If we turn the nitrous back on it's going to lift a head like the last one.

jeffmarsh750 · Post by **jeffmarsh750** » Fri Jun 17, 2016 3:21 pm

Maybe this datalog will work better

Post by **jsmcortina** » Fri Jun 17, 2016 3:38 pm

I hope somebody else will be able to chime in here as I'm away for a few days.

James

Matt Cramer · Post by **Matt Cramer** » Mon Jun 20, 2016 11:18 am

Can you log a couple specific variables? I'd like to see PORTK to see what the launch input port is doing, and both STATUS2 and STATUS3 to see if it is commanding the 2 step or some other spark cut.

jeffmarsh750 · Post by **jeffmarsh750** » Mon Jul 11, 2016 10:13 am

We found something interesting with this. The ignition timing is off 6 to 8 degrees on one channel. This was not like this on the initial install nor did it miss fire at all at high rpm last year. Is there anything in the ecu that maybe it possibly has a weak driver on channel B spark output ? We can adjust the compensations but this is throwing up a red flag. Changed the quad spark and coils with no difference. Has an 8-1 wheel and all teeth are evenly spaced. Any ideas ?

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Going back on 2 step at end of track ? Ideas ?

Going back on 2 step at end of track ? Ideas ?

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Re: Going back on 2 step at end of track ? Ideas ?

Re: Going back on 2 step at end of track ? Ideas ?

Re: Going back on 2 step at end of track ? Ideas ?

Re: Going back on 2 step at end of track ? Ideas ?

Re: Going back on 2 step at end of track ? Ideas ?

Re: Going back on 2 step at end of track ? Ideas ?

Re: Going back on 2 step at end of track ? Ideas ?