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crf450r gears in a crf450x engine????

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My friend has a 2005 crf450r which he would like to add electric start to. So here are the questions.

will a 450x engine fit in his 2005 crf450r frame?

can he take his crf450r transmission gears and put them into the crf450x engine?

He has a 2007 crf450x engine already now. will this later model motor bolt into his 2005 frame? will this motor also accept all his race oriented R parts like the cylinder etc?

what electrical harnesses would he need to charge battery and how hard to put this into his R frame as well as mount a battery?

I told him to buy an X but he prefers his R except for the fact no electric start but he doesn't like a wide ratio trans that the X motor has.

any help greatly appreciated!

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I'm pretty certain that the X engine won’t drop into the R frame but if you know a good aluminum fabricator it can probably be done. I’m not sure where you would put the battery and other electrical components on the R. You would probably need an X subframe and plastic. There is also some sort of charging system to think about.

You gave him good advice to buy an X. I think it would be easier to start out with a bike that already has e-start and make it more like a 450R. It might be a fun project though.

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My friend has a 2005 crf450r which he would like to add electric start to. So here are the questions.

will a 450x engine fit in his 2005 crf450r frame? no

can he take his crf450r transmission gears and put them into the crf450x engine? no

He has a 2007 crf450x engine already now. will this later model motor bolt into his 2005 frame? will this motor also accept all his race oriented R parts like the cylinder etc? no

what electrical harnesses would he need to charge battery and how hard to put this into his R frame as well as mount a battery? N/A

I told him to buy an X but he prefers his R except for the fact no electric start but he doesn't like a wide ratio trans that the X motor has.

any help greatly appreciated!

Best bet would be to get an X chassis to put that X motor in. "Gappiness" of the X's wide ratios is an easy fix with minor gearing changes. X chassis, gearing, gearbox, heavier crank, etc. is purpose built from the ground up and a totally different animal than the R. A tuned 450X will make as much power as an R but better useable power. The X is considerably heavier but sometimes that's an advantage too. :banana: Good luck!:lol:

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