MXA PRODUCT TEST: L.A . SLEEVE YAMAHA YZ272F KIT

 

 

 

WHAT IS IT?

Memorize this phrase: “There’s no substitute for cubic centimeters.”

 WHAT’S IT COST?
$1398.95 (pipe, cam, cylinder and piston kit)(562) 945-7578.

www.lasleeve.com

 WHAT’S IT DO?
The 250F four-stroke craze has created a unique problem for your typical Vet racer. It’s a choice problem. They love that they don’t get as tired on a 250F as on a 450, but hate how they get beat on the track by their buddies on 450s. It becomes almost cyclical, as a guy will buy a 450 one year, get tired of it dragging him all over the track and buy a 250F the next year. Then on the 250F, he’ll get tired of being beaten by every yahoo on a 450, and buy a 450 again the next year.

The problem has gotten worse as all five manufacturers now offer 250Fs. Back in the golden, olden two-stroke days, you’d occasionally see someone trying to race a YZ167 in the Vet class, but, to be honest, they weren’t at all competitive against 250 two-strokes. Now the big-bore companies are offering oversized 250Fs. The latest one to fall in our laps is L.A. Sleeve’s YZ272F.

WHAT STANDS OUT?
Here’s a list of things that stand out with LA Sleeve’s YZ272F kit.

(1) Parts. This may surprise you, but the sleeve is the second cheapest part of L.A. Sleeve’s kit at $90. The high-compression piston (13:1) is $198, gaskets $57, machine work $115, Webcam camshaft $423 and DR.D exhaust $515.95.

(2) Performance. Most big-bore 250Fs end up going too big. They try to create a mini 450 and end up with a hard hit, short rev and lots of decompression braking. L.A. Sleeve’s kit only jumps up to 272cc, and they avoided the big-bore curse by having Webcam and DR.D produce a cam and pipe that add equal amounts of bottom, mid and top.

On the track, the YZ272F runs much like you’d expecta 250F on steroids. It comes on stronger down low, pulls harder in the middle and runs until it hits the rev limiter.

(3) Problems. With the additional horsepower L.A. Sleeve’s 272 kit put out, the stock YZ250F clutch just couldn’t handle it. We fried a clutch in a single moto. The only way to get a clutch to last in the 272 was to go with stiffer clutch springs.

(4) Place of Manufacture. L.A. Sleeve’s YZ272F kit is made in the USA.

WHAT’S THE SQUAWK?

The fact is, 450s are still going to pull you.

 

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