Norton 961 Compression Test

Jan 16, 2015
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Hello , I thought I would test my compession again and I was surprised to find it so high. I was expecting 150-160 psi and I was wrong.

Left cylinder 176 psi

Norton 961 Compression Test

Right cylinder 180 psi

Norton 961 Compression Test

Current mileage

Norton 961 Compression Test
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That motor seem pretty healthy.
Whatever you're doin', keep doin' it.
Folks, what is the correct procedure to carry out a compression test on a 961 ?
Thanks @Stu Bodycote & @City Garage I should have been more specific. I was wondering if I need to pull the fuel pump relay, but I hadn't thought of disconnecting the fuel pump.
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No, just unplug under the tank. It will keep you from getting an initial blast of air-fuel at 150psi ish or more coming out.

Also, you can do it cold( you will get lower numbers than warm), but the consistency is really what you are looking for. Cold tests happen all the time on no-start conditions.

Ideally, like Stu said, warm, WOT
Carried out the test tonight straight after riding home from work ( yes I commute on mine).160 psi left & 155 right, so right in the middle of the spec.