02 cr 125 motor work

whats the best way to modify the motor on my 02 cr125? i talked to a local tuner and he said the ports were too big. he did say using epoxy to make them smaller would work though he doesnt have a lot of experience working them. what about different heads like phathead or VHM? also i remember seeing in a magazine that team geico(previously amsoil) had turned it into a long rod motor and also what of strapping on a 97 cylinder?

If he doesnt have alot of experience with Cr motors, you probably shouldnt listen to him.

Ask somebody else

sorry i miss quoted. he didnt have a lot of luck getting them better. not that its not for trying

Eric Gorr's tuning book talks about the 2002 CR125 cylinder have ports that are too large. He recommends a Wiseco 755MO5400 piston for a RM125, which will slightly change port timing in favor of low/mid power. The head will then need to be cut to match the piston.

He also mentions that the cylidner/crankcase has a horrible overlap and needs matching, and I believe the crankcase has too much volume to be ideal, which requires epoxy to fix.

Eric Gorr's tuning book talks about the 2002 CR125 cylinder have ports that are too large. He recommends a Wiseco 755MO5400 piston for a RM125, which will slightly change port timing in favor of low/mid power. The head will then need to be cut to match the piston.

He also mentions that the cylidner/crankcase has a horrible overlap and needs matching, and I believe the crankcase has too much volume to be ideal, which requires epoxy to fix.

which year piston would that be for?

According to Wiseco's application guide it is for 1999-2003 RM125

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