XR650R engine in a CRF450X frame

[rmhrc630]

Has anyone done this?

I'd like views on the following important issues (plus advice on others not mentioned)

1. Oil tank - could I use the CRF frame as an oil resevoir?

2. Sheer engine size - will the 650R engine even fit inside the stock CRF frame?

3. What if I were to use the XR main frame, weld on CRF spars, headstock, use CRF back end/swingarm etc? I know it would require 2 frames but so be it.

4. Other issues?

[jokerflingo]

Has anyone done this?

I'd like views on the following important issues (plus advice on others not mentioned)

1. Oil tank - could I use the CRF frame as an oil resevoir?

2. Sheer engine size - will the 650R engine even fit inside the stock CRF frame?

3. What if I were to use the XR main frame, weld on CRF spars, headstock, use CRF back end/swingarm etc? I know it would require 2 frames but so be it.

4. Other issues?

All i know is it wont physically fit in the frame.

[BOLT Performance]

Anything can be done. But at some point you gotta ask yourself why ? 👍

[jokerflingo]

Anything can be done. But at some point you gotta ask yourself why ? 👍

Wank factor?🤣

[rmhrc630]

Anything can be done. But at some point you gotta ask yourself why ? 👍

I like your casn do attitiude

450X ergos

650R power

pretty simple to me

[BOLT Performance]

The 450 can have just as much power as the 650 without the weight. That was the point of the bike ! I put a HP 302 into a Ford Courier in 1982. So like I said anything can be done. But it went fast and didn't handle for shit.

[rmhrc630]

The 450 can have just as much power as the 650 without the weight. That was the point of the bike ! I put a HP 302 into a Ford Courier in 1982. So like I said anything can be done. But it went fast and didn't handle for shit.

Fair call - I did read the 650r engine is 10kg heavier than the 450X engine.

It just strikes me that the 650R donk is a great donk so putting it into a 450X frame would be the ducks guts

[PNW_XR]

This is kind of like putting a Cummins diesel into a Charger. Why?

[Nummie]

This is kind of like putting a Cummins diesel into a Charger. Why?

The real question to ask is why not? Sounds interesting.👍

[ThumpNRed]

After you chop up a couple of frames to get it to fit, you will likely have a bike that is heavier than an XR650R and doesn't handle worth a darn. It would be unique though.

If we all used common sense, we wouldn't be tinkering on our XRs to start with... So... get busy collecting parts and let the party begin!

[bongodave]

If you manage it, you'd have a motor that doesn't have to be rebuilt every 6 months.

[scalejockey]

Iv'e kinda thought about this and had 450 next to mine at one point while both had the tanks off.It could work but... the 450 would have to find a new place for the gas,as the 650 motor is about 7 inches taller and 4 inches longer.

I think the only answer would be a fork and shock\swing arm transplant from the 450.

Sorry i can't do it,That's time spent that i could of been riding....

[ThumpNRed]

Iv'e kinda thought about this and had 450 next to mine at one point while both had the tanks off.It could work but... the 450 would have to find a new place for the gas,as the 650 motor is about 7 inches taller and 4 inches longer.

I think the only answer would be a fork and shock\swing arm transplant from the 450.

Sorry i can't do it,That's time spent that i could of been riding....

A case of beer and a heliarc... we could make it happen!👍

[motomanx]

just put a CRF front end on your 650R and be done with it.

BTW, if built correctly and taken care of, the 450X will last quite a bit longer than 6 months.

I have a 450x with 300+ hours on it.

It is no XR, but what is??

BTW, I ride my XR mostly.