Compression test.
 

Hello, i am about to do a compression test on my 1999 1500 Nomad and i need to know the figure's to expect,good and bad, before anyone say's, buy a manual, ive got one,a Hayne's, have you tried finding something in it,it is so all over the place that it must have been compiled by someone with dementia.I cant find the link to the manual on here either :shrug: any help would be appreciated.:cheers:

See if you can find the compression ratio of your bike.
per the evans tuning checklist:
8:1-8.5:1 compression: 150-170 psi per cylinder
8.5:1~9.5:1 compression: 170-210 psi per cylinder
9.5:1~11:1 compression: 210-275 psi per cylinder
11:1+ compression: 250+ per cylinder (also depends on cams being used)
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If you have compression but still have symptomatic engine issues, get a leak down test run. That will spot how fast the compression leaks off.

Read the manual on how to do a compression test, there are KACR's (compression release valve) to aid in starting, which can give you a false reading if not done correctly.

Sent you the link for manual in pdf form Mick. Check your pm's.

As ringadingh mentioned it can be difficult to get good compression readings due to the compression release mechanism built into the valve train. I suspected I had a cracked ring so attempted wet/dry open throttle compression tests with only one plug removed and all plugs removed. Never was able to get readings that repeated itself but was able to deduce the compression was high enough to rule out a cracked ring.

I cant get anything on that link mate, only basic spec's like in a dealer's brochure.:tup::cheers:

That's the information that i am looking for, but nothing is where it say's it is in the Haynes manual and it really pisses me off to even look at it >:( i was hoping someone with more patience than me would send me a link to the bit that i need :D :cheers:

Hello mate:wave: and thank's for that :tup: but i reckon that's a bit vague for what i need,there are a lot of variable's in there.:cheers:

The compression ratio for a 99' Drifter (Classic, Drifter, Nomad, Meanstreak should all be the same ratio) 9.0-1, so the compression should be 170-210. Both should be within 10% of each other (that is the important part).

:wave: I knew i could count on a colonial :D only an Englishman can travel all over the shop and still be just that :tup:







http://i233.photobucket.com/albums/e...Englishman.jpg

Just passing it along.........I owed some Limey sailors for getting a drunk Yank back to the ship in Athens, Greece. Not the right ship but at least it was the right type ship.

Anything newer then 2001 could be FI, those motors had a higher compression rating and used different rings then our carb d 99s, I went with 03 FI rings at 9.5.1 when I did some performance upgrades