[HondaATC]

Does anyone know anything about the Rotax 800cc snow-mobile cylinder swaps onto the 250R? I think Packard and a few others have built them. Considering building one...interested in knowing what year machines the cylinders come off of, pv or non pv, what rod to use, original engine stroke length, etc. etc.

 

[StrokeitTwice443]

thats a first for me. i've heard of the Polaris cylinders being used, but not the Rotax.

 

[HondaATC]

http://www.3wheelerworld.com/attachment.php?attachmentid=81923&d=1254640110

Its hard to see, but look at the cylinder on the red bike.

 

[2strokefan]

I'm pretty sure it can be done, but I have no idea what would be involved. Maybe you can contact C-Leigh Racing over on 250r.net. He's really good when its comes to these 250R's.

 

[HondaATC]

http://www.3wheelerworld.com/showthread.php?75264-ski-doo-top-end-on-250r Heres an old thread on 3WW I dug up that has some more (better) pictures of the setup.

 

[flotek]

packard is the guy who did them they used a outer starter and bumped them alive
id just call him and pick his brain ,seems like kind of a one off project to do without the aid of someone who has done them in the past might be very involved

 

[traxman]

Not sure on the year but the four I've delt with have a 6mil stroker with a yz 490rod and a 87mm yz490 piston giving it a 463cc displacement. you can set them up for all different rod stroke combo's.

 

[HondaATC]

I know the YZ490 rod can fit on a 250R crank with minimal modifications, so knowing that makes it alot easier. The welding of the cases and drilling/tapping for the studs doesn't really worry me that much. This sounds like it could be a pretty fun project. Have to have my buddy in Alberta hunt up a cylinder and head for me. Stay tuned, see what I can cook up in my shop If anyone else has any other info I'd appreciate it too!

 

[volfan537240]

sounds interesting!!

 

[CR480R]

cylinder comes from a ski-doo 800 twin

 

[Paulie B]

Seems like a fair amount of work to get 400cc's.
I suppose if you like to play and have the time it's all good.

 

[HondaATC]

I've done the CR500 motor conversion thing before, and I'm the type of guy that hates cookie cutter stuff....I could spend $1500+ on an ESR350 kit or I could spend a couple hundred bucks in parts and some welding/machining time and have something that there are probably less than 2 dozen motors in the world floating around as, I'm going for the crazy wacky weird thing

 

[Chuckie]

i dont know if theres anything specail about the 800 twin but sea doo makes a 951 twin maybe you could use one of those cyls and get more cc?

 

[Paulie B]

I've done the CR500 motor conversion thing before, and I'm the type of guy that hates cookie cutter stuff....I could spend $1500+ on an ESR350 kit or I could spend a couple hundred bucks in parts and some welding/machining time and have something that there are probably less than 2 dozen motors in the world floating around as, I'm going for the crazy wacky weird thing

I do the same thing lol

 

[2strokefan]

Do you know what would happen it I tried to cut and weld on some cases and cylinders? NOTHING!!!........except I'd have a nice paper weight!!:LOLsign:

 

[CR480R]

i dont know if theres anything specail about the 800 twin but sea doo makes a 951 twin maybe you could use one of those cyls and get more cc?

they use the 800 cylinder because it offers a larger bore, powervalve, and a huge cylinder reed cage... most sled engines have case reeds, and are tripples with small displacement per cylinder..

 

[2-330s]

look around exriders jon *** built a few of these

 

[HondaATC]

Welp I am the new owner (as soon as it arrives) of a 2004 Ski-doo 800 REV cylinder

 

[volfan537240]

this is gonna be an awsome build!

 

[RichM1983]

Im posting to subscribe. Please keep us updated!