Posts
153
Joined
1/24/2019
Location
Clark Fork, ID, USA
I have a beta 200RR and just checked compression. Builds to around 180 and then leaks off. Bike only has 20 hours on it. Is there anything obvious I can check before I start assuming it’s the rings ?
Ensure the compression tester doesn't have a leak, too. If there's a way to dead end the compression tester under pressure, that's always a good first step. Additionally, and alternatively, listening/watching for the leak is key --- for example, when spraying soapy water around the seal at the spark plug o-ring, does it obviously leak there?
Once you're sure the tester is good, start troubleshooting the bike.
Lastly, is the bike running poorly or are you just trying to get a baseline reading?
I’ll check the soapy water and report back. The bike is running great, was just wanting to get a baseline and looking into a high compression head
Definitely don't assume your bike's rings are going bad if it's running great. I've done this in the past when I was "too by the manual" ... then realized I was faaaar from a pro rider (and how awesome the protection/ring seal Maxima K2 provided) and I could go 50+ hours on 250cc 2-stroke top-ends.
A baseline is a great idea! A post on Vital asking what to expect is a good idea, too (even if the manual gives a spec, other real-world owner readings are gold).
You have a bad compression tester. The tester is what holds the pressure during a test. Remember as you are kicking or cycling the engine it loses compression when it opens any of the ports.
Your tester has a leak internally.
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Do you hear it leaking out the exhaust or intake?
Post a reply to: Compression dropping rapidly during test