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Project 2-4 update

3517 Views 4 Replies 4 Participants Last post by  mscuddy
Project 2-4, where we took a modern four stroke frame, and stuck an air cooled two stroke MX motor from the late 70's in it (in this case a '79 RM250 motor) is nearing completion.

The bike will tip the scales at 214 lbs, put out 39 horsepower and will sport a custom built down-pipe.

Also it will not blow up every fifteen hours, and should haul ass, without the pain of a three thousand dollar rebuild every six months.

So watch out all you four strikers! Stay tuned to for the latest poop on the project bike.
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Look in the motorcycle for sale section of any Recycler or free ad publicaiton and you'll find literally dozens of KX CR & YZ four stroke's a couple years old with blown motors for $600.00 and up.

Source a decent air-cooled two stroke motor from a salvage yard, and with a little fabricaiton and drilling you get an unbreakable dirt bike with the latest frame and suspension tech. The biggest pain is fabricating the expansion chamber, had to cut the stock pipe up and re-configure as a down pipe.

I wanted to get a YZ465 motor but Rick wanted a 250. So we got a sweet RM250 from a '79 basket case for $200.00. The whole cost of this is right aorund $1,000.00. (for a 214 lb, bike that puts out 39 hp).

Should be done today sometime after Rick welds up the chamber at his buddy's house who has a Monomag 400 wire welder (the only way to get a good bead is with a gas shield).
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