MicroSquirt.com read only forum (Jan.15,2018)

this is on a Honda CBR f3 600, running MSnS -e newest code version (c13?) on a v3 board, 12 - 1 trigger wheel and wasted spark.

the motor will rev to 11500 without problems (breathing through a restrictor) but hits a very strange fuel cut at about 9500 rpms. During this time it sounds like it is bouncing off of the hard cut rev limiter, and on the VE table in MT the green tracer dot drops to 0 rpm/0 load for fractions of a second while the motor cuts out...with enough persistance with the throttle, it is possible to throttle through there, but it definetly sticks for a few seconds before continuing. this happens at all loads at the same 9500 rpms every time.

the actual hard cut is set to 12500 rpms, and the soft cut to 12000, so thats not the cause. i was thinking perhaps the ecu had some sort of issues counting teeth at that particular rpm? it revs and responds fine at rpms above that though, so i dont know what it is about 9500 rpms that is giving it problems.


any insight is much appreciated. thanks!

Hi, i will convert a CBR 900 to EFI. At this time only fuel, but i want control spark too.
I have a couple of cars convert and i have some problems like yours, but at aronund 7000 rpm. The two fixes were a shield vr cable and move close the vr sensor. Have your bike VR or Hall sensor?

Please, tell me if it solve your problem.

Regards

Miguel

we were able to solve the problem partially by adding a bit more fuel in the rpms that the motor was cutting out at. its a VR sensor if i remember right (only two wires), so adding a shield should help, but the it doesnt currently run. i will add a sheild as soon as we get it going again.

thanks for the tip!