analyzing Relative compression results

CycleImp · Post by **CycleImp** » Mon Nov 11, 2019 3:18 pm

Is the any way to get useful data from a relative compression test on an uneven firing engine like a V Twin or V 4?

Thanks

Post by **Steve Smith** » Wed Nov 13, 2019 4:07 pm

Hello and thank you for the post.

Regrading "useful data" from your relative compression test could I ask if this is to determine the offending cylinder?

If so, then the following Case-Study from Ben describes the approach taken for a Parallel Twin engine.

Whilst this is not your V Twin, the techniques describe the application of PicoScope and a current clamp to determine cranking effort (relative to compression) via the starter motor current draw.

Introducing a second channel to capture the ignition event of cylinder 1 will help identify each cylinder

I hope this helps, take care.....Steve

CycleImp · Post by **CycleImp** » Wed Nov 13, 2019 4:21 pm

Hi Steve, that is exactly what I was looking for, thanks so much. James

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