This auction is for one billet aluminum Y-piece designed to convert an 02-07 CR125R to accept a 1989-2001 CR500R engine.  This is not an auction for the completed frame just for the Y-piece. This Y-piece is machined from solid blocks of 6061-T6 aluminum, then de-burred in a media tumbler.  The front engine mount is machined into the Y-piece such that you will not have to fabricate front engine mounts. The ends are machined to fit inside the tubing of the frame to allow the strongest possible welds.  With this Y-piece, you do not have to replace the square tubes that run under the engine.  I have many customers who have used this Y-piece for their conversions and I have received no complaints but many of them have commented on how much they like it.  As you can see from the images it makes a very clean looking conversion.   CR500 engines from 1985 to 1988 can be used but require the swing-arm bolt bushings in the rear of the case to be modified. 

Download the Conversion Manuals. These manuals included detailed instructions and photos on how to perform each of the modifications for great looking results.

We offer billet aluminum Y-pieces, engine mounts, coil mount bracket, exhaust and silencer mounts, airbox adapter plates and radiator outlet parts for various engine conversions. We also offer complete kits at a discount. 

Check out our store ConversionParts500 for all of these components to make your conversion easy. 

We will combine shipping if you purchase items together and notify us that you would like them combined.

We are happy to provide our contact info to anyone who purchases a part so they can contact us with questions about the conversion process.


02-07 CR125R chassis:
-This conversion makes a very fast and light bike that handles extremely well.  
-The CR125 chassis is almost the same size as the CR250 chassis, but it has a steeper fork rake for better tight track handleing. 
-The CR125R chassis are cheaper and easier to find.  You can usually buy a whole bike then sell the engine, carb, exhaust and electronics on ebay to recover most of the cost of buying the bike.
-The swing arm bolt and spacers are the perfect width, so you don't have to modify anything with the rear engine mount or swing arm spacers.
-The gas tank has a nice cavity in the bottom of it in just the right place to clear the spark plug and coolant hoses, so you don't have to modify the fuel tank at all.
-The only thing you have to do to make the airbox work is to replace the rubber boot with a boot from a 2000 CR250R.
-This conversion does require a fairly significant pipe modification to allow for full compression of the front wheel.