Probably getting too much fuel, will have a bit more a play soon
Its been a good couple of years since I lastt played with MS, but I am trying to help a mate set one up on his V-twin LSR bike. Its off to the salt
flats soon, so trying to get it sorted out.
We have spark and fuel, but all its doing it making fireworks from the exhausts, its kind of firing. But wont start.
There are some odd things going on, but waiting for an answer from the MS extra guru on the extra forums.
My question is whats the normal reason for the exhaust explosions? Cam timing has been check and is spot on, spark seems to be coming in the right
place as best we can check.
[Edited on 7/4/12 by flak monkey]
It's not an odd-fire engine is it?
See the discussion here http://www.locostbuilders.co.uk/viewthread.php?tid=56206
Yes it is odd fire. 50 deg v-twin with 2 crank triggers 50deg apart both triggering 8 deg BTDC. So we are using the twin trigger set up.
We get 2 sparks on cyl 1, one at the right timing, and one 50deg after. Only one spark on cyl 2, at the right timing. Obviously cyl 1 isnt right, but
it shouldnt matter that much as cyl 1 has already fired and is on its power stroke.
We are using extra code, with microsquirt (MS2) with built in coil drivers. Using seperate coils for each cylinder.
Isn't it due to sparking when the exhaust valves are open to get backfiring (with a cold exhaust).
Are you running it as wasted spark?
You could unplug the HT leads or injector power in turn to see which cylinder the backfire is on.
What is the engine?
Thanks Matt, that's along the lines of what I was thinking, however the timing checks out to be right with the timing light, hence why we also
checked cam timing. It is running as wasted spark, yes.
The engine is a Weslake 1000cc, DOHC v twin. Bit unusual, there's something like 6 of them in existance. Never was a production engine AFAIK.
timing 180 degrees out??? firing on the exhaust stroke perhaps.
It's wasted spark, so will fire on the exhaust stroke anyway won't it?
Probably getting too much fuel, will have a bit more a play soon
quote:
It's wasted spark, so will fire on the exhaust stroke anyway won't it?