polaris scrambler 400 cylinder on a 250r bottom

[joshridina400ex]

anyone have any info on this project? pics?

[honda300EXtreme]

Is that even possible??

[f150mann]

all odds would lean to hell no, but, nothings impossible

[honda300EXtreme]

thats what i was thinking i have never even heard of doing this before

[honda300EXtreme]

thats what i was thinking i have never even heard of doing this before

[wilkin250r]

It has been done a few times, commonly called the "polonda". If memory serves, they are the same stroke.

Most often with hybrid motors, you need to do extensive welding and case modifications, relocating base studs to fit a cylinder from a different motor. With the Polonda, however, all those modifications are made to the cylinder. The only mods to the case are standard case boring to accept a larger sleeve. You could later switch back to a standard Honda cylinder, because the studs weren't relocated.

The cylinder needs fairly extensive mods, as well as a spacer plate to fit.

[joshridina400ex]

wilkin250r do you know where i can find more info about doing this?

[honda300EXtreme]

huh... i never knew that... i learn something new every day

[wilkin250r]

Originally posted by joshridina400ex
wilkin250r do you know where i can find more info about doing this?

Not really. A google search for "Polonda" will give you several hits about general information. People that have done it, the results, possible a dyno run or two. But I really don't think you are going to find SPECIFIC details on how to accomplish it.

You'll learn that you have to weld/move the water passages, but you won't learn how/where to actually move them.

You'll learn you need a spacer plate, but you won't get details on the thickness.

Several different pistons can be used for different size configurations, but you won't find any details on how to get those pistons to fit the stock 250r crank.


I've been able to find links describing the power and feel, and rider's reviews, but I haven't found anything on the DETAILS of building the motor.

[rundrave]

heres a link, not sure if you all have seen it:

http://www.atvsource.com/articles/pr...nda_engine.htm

also I thought I saw some talk of this over on gen3usa.com

http://www.gen3usa.com/forums/viewto...=polonda#27952