Apr 1, 2008 · Actually, I had a ported/milled Varner cylinder on my '01 YZ125. It was, hands-down, the fastest 125 I have ever ridden. I pulled good starts at Glen Helen on that bike against 250s and 450s.

Apr 20, 2014 · A mid/top port job will be exactly what you are looking for. Runs just as well as a stock motor but pulls further than stock with better over rev. That means less shifting!

Apr 13, 2015 · Has any one done any kind of porting or polishing to a 2 stroke cylinder themselves? I only have a Dremel and was wondering if I could do anything at all myself to my yz125 before I put it together. Is it worth it and is it reliable? Or should I …

Nov 20, 2012 · Plan was to do DIY porting or at least match the cylinder to crank cases better. If you have any good advices I am thankful to hear. there below is some red marks what I am planning to remove in order to achieve better flow.

YZ125 144 Cylinder Conversion | $1250 Our yz144 has pushed the amount of power thought possible out of a yz125. We have hit 45 hp on some builds! Requires case clearance.-Cylinder boring-Stage 3 144 porting, tailored to each customer-Powervalve machining-144 head machining specific to fuel and customer-Replating-Piston and gasket kit

Porting for the following models, according to the specs of Eric Gorr, can be read about in his book "Motocross & Off-Road Performance Handbook ": 1999 - 2004 Yamaha YZ 250 for more top end power. 1992 to 1998 Yamaha YZ 250 for more top end power. 1994 to 1996 Yamaha YZ 125 for more top end power. 1990 to 1999 Suzuki RM 125 for more top end power.

Dec 17, 2007 · I want to talk to the guy who is actually porting the cylinder. There is a difference because I have personally used or ridden the tuners bikes for comparison. Terry Varners work is really clean and the HP gains are huge.

Jan 22, 2019 · Cylinder ports are cleaned, exhaust port is polished, polished cylinder head, cases and cylinder are matched (crank case with epoxy). I have swapped a carburetor to Keihin 38mm air striker from 2008 rm250.

Dec 11, 2023 · Porting - what it actually does. Cylinder porting is where you can make or break the power-band on a 2 stroke engine. The YZ125 has pretty good ports from the factory, but there's always room for improvement. If you don't know what you're doing, I strongly warn you NOT to port the cylinder yourself. It's very easy to make it run worse.

Feb 15, 2009 · Don't have any business modifying a motor. They don't know how to jet, adjust timing, or run proper fuel. 2. Run the motor past it's intended service intervals. 3. Expect too much from the motor.