Thread: How do I know which upstroke sparks fires at tdc on my 96 Suzuki 250 2 wheel...

...drive quadrunner? How do I know which stroke sparks on my 96 Suzuki 250 2 wheel drive quadrunner? I am putting the cam in as pictured in the manual but how do you know when you are at true TDC and its firing and both the valves are shut? You are supposed to set the cam at TDC but it has to be the right one . . . so how can you tell when its the one that fires?

The one that's coming up to fire well make compression. The other should have the exhaust valve open on the way up. So one will blow your finger out of the hole. You can also check to see were you are on your harmonic balancer and this will tell you.