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03 KX 125 Cranking compression questions

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I picked up a 03 KX 125 a few months ago and I've been running a blend of 50/50 av gas premium blend in it. I checked the compression yesterday with a snap on gauge and it is 215 PSI:banana: I'm thinking I might need a little more octane than I am running. I do not see any deto marks on my plug, but it does have me a little worried because it is much higher than any of my other two strokes. My blaster had 160psi and I ran 93 in it, and my superjet has 175 and I run the 50/50 av blend and it is on the edge. I know the correct way to find your octane requirements is to determine your true compression ratio, but I'm feeling kinda lazy.

Is this a normal compression for a kx 125?

Should I bump up the octane?

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Wow, 215 is high as hell!

id say you should be running race gas. might try calling a shop, my bikes are built to run on pump gas and they are both 180 new. after break ins are done its 170.

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Wow, 215 is high as hell!

id say you should be running race gas. might try calling a shop, my bikes are built to run on pump gas and they are both 180 new. after break ins are done its 170.

Yeah I think i'm going to start running at least vp red in it. I'm happy that the motor has some stuff done to it, but I really don't need to be running race gas for trail riding and some small climbs. Maybe i'll have to tear it down and send it to eric gorr. Oh darn:smirk:

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215 is really high. Too high? Has the bike been modded for race gas with head/piston mods?

I wouldn't think it would run well at all on pump gas with compression that high.

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Static compression is only one factor in the octane requirements of an engine. The peak combustion pressures and temperatures determine the octane requirements.

To keep it simple, if you aren't experiencing detonation, you are running enough octane. there's no benefit to going any higher.

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