Compression Tester Recommendations

[Greg]

I have come to the conclusion that if you are going to work on scoots, having a compression tester is a must.
I first bought a harbor freight model (95187) where the hoses were too long and all my scoots had 30 to 40 psi for compression.
I took that one back and now I have a second tester from Harbor Freight (66216) with shorter hoses. It seems to be closer to accurate, but still not right.
A new 39mm gy6 bore gives me a reading of 165psi. Another Gy6 50 gives me a reading of 150 psi.
165 psi has been the highest reading I have seen.
Is there such thing as an accurate, yet inexpensive compression tester?
I guess I get what I paid for at $20.00.

[90GTVert]

The second one sounds like it's working. The discrepancy between the two engines is likely the engines themselves, not the tester.

I have an old Snap-On tester that works well. I just picked up an Actron CP7828 because the Snap-On has no 10mm adapter and they don't seem to make anything for this tester now. It's a different style than most, so generic adapters won't work. Anyway, the Actron looked like a decent unit to me at a low price. I have not tried it yet, but I've got some of their other products and have been satisfied with them as reasonably priced tools. The other products have been electronics though mostly, OBDII scanner, multimeter, timing light, stuff like that.

amzn.to/1HW0Aqi

[Greg]

Thank you.
That model 7828 looks like something I will try. Conveniently sold at Sears also.
I need to first hook up my air compressor to my current compression tester. This way I can compare the testers psi to my compressor tank and hose gauges to see how far my current tester is off.
I did this with the first tester I bought and the tester read 100 psi correctly. Something was lost with the long hoses so that it could not read the small stroke correctly. After buying it, there was a review from a guy working on snowmobiles who had the same problem reading correctly.