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You can send in your working or non-working HPI engine along with your payment and take advantage of this engine exchange program. If you send in an HPI engine, you can choose any one of the engines below. The 21BB exchange is available only if you send in a 21BB engine.
The engine that you send in does not have to run and may be disassembled.
Damaged parts are acceptable (broken head fins, broken pullstarter, broken con rod, etc.).
It should be as complete as possible (no missing con rod, pullstarter, carb, head, etc.)
Remove any mounts, flywheel/clutch, exhaust and air filter before mailing the engine to us.
California residents must add 7.75% state sales tax to the total.
The engine that you receive will be BRAND NEW. We will not send you a rebuilt or remanufactured engine.
Originally posted by error401
Doug, It wouldn't hurt to try. If the 21BB 1 way will fit on the crank shaft of the 25, it should work. I've heard that the roto start will fit on the 25, so there's a good chance that the 1 way will fit the 25. If it don't fit, it won't work. The 1 way is just a camming roller bearing.