Did a compression test on my Elite...help

[Kerry]

well, she runs great, plenty of power and i'm a big guy but it looks like 59#'s of pressure. how bad is that? I'm a scooter newbie. I'm kind of surprised as my 92 elite has only 1,500 miles.

Suggestions on what to do..again, I'm a novice but I'm learning like crazy.

thanks!

[Wheelman-111]

Greetings:

If it ran before, I'd suspect an inaccurate gauge reading. Any kind of fitting leak will cause the PSI to read low. My cheapo Harbor Freight came with several different adaptors, even though the end that's attached to the hose fits the plug threads directly. If I try to use the adaptor, the pressure reading drops significantly.

If the reading truly represents your engine's compression, it's pretty bad. If so I see a Big-Bore Kit in your future. That's not necessarily a bad thing...

[Kerry]

It runs wonderful and hauls my fat 260 6'2 jazz around no problem 30+.

I borrowed the gauge from Vato Zone. I did have to use an adapter, it came with two...one larger and the one from the scoot plug. I was shocked!

Maybe ill use thread tape on all connections and tighten it more?

[Wheelman-111]

Greetings:

You can try the thread tape, or This. For ten bucks, it's hard to go wrong, and you'll know if it's your AutoZone gauge or the true compression.

[mustangwagz]

Your are holding throttle WIDE open while cranking, correct?..

i did my scooter with the throttle closed, and it also came up 60psi...

just a thought..

[Kerry]

I left the throttle closed...is that my problem?

[Bear45-70]

I left the throttle closed...is that my problem?

Yes, to do a proper compression test the throttle much be at WOT. A closed throttle restricts air flow into the engine which lowers the compression PSI.

[Kerry]

Did it twice with wot and its the exactly the same reading. I'm thinking it has to be the gauge due to 4 tests with all the same results and two with wot and two with the throttle closed.

Ideas or comments until I get a new tester?

[Trafficjamz]

Why are you doing a compression test if your scooter runs "great" ?

[Kerry]

Just to know basically. I'm somewhat Ocd on anything I own with an engine. I like to know as much as possible and become educated. When I got the scooter I knew nothing of its history so I went right through it from plug,belt,cleaned Carb,filter,gear oil etc. So, its free to borrow a comp tester from auto zone so I figured, why not?

Didn't need it, but I like to know...is that cool it a good enough reason for you LOL?

[eliteguy50]

Why are you doing a compression test if your scooter runs "great" ?

To properly maintain an engine, the rings should be replaced before compression reaches the point of not running. They all have a service limit and are more likely to break when run too long.

[eliteguy50]

Did it twice with wot and its the exactly the same reading. I'm thinking it has to be the gauge due to 4 tests with all the same results and two with wot and two with the throttle closed.

Ideas or comments until I get a new tester?

It still could be that your engine has low compression. When compression gets so low, opening the throttle doesn't really have much effect. I have an engine on the bench now that reads the same with no carb at all as when it was mounted in the bike.

[Kerry]

if this is true, how does mine run perfect? I did research on other sites and on a few, I've read

"A motor must have a minimum compression rating of at least 100 to 125 pounds per square inch to operate properly."

is this not true?

Did it twice with wot and its the exactly the same reading. I'm thinking it has to be the gauge due to 4 tests with all the same results and two with wot and two with the throttle closed.

Ideas or comments until I get a new tester?

It still could be that your engine has low compression. When compression gets so low, opening the throttle doesn't really have much effect. I have an engine on the bench now that reads the same with no carb at all as when it was mounted in the bike.

[Kerry]

let me add that this info was on 2 stroke scooter motors.

[eliteguy50]

Different motors require different conditions to run. I've had engines that ran just fine at 60 PSI cold. I've also read about engines that wouldn't run at 107PSI and had a broken ring.