XR650L build and swapping XL600R parts

[MentalGuru]

I have a 1994 XR650L that needs second gear. I also have a XL600R parts bike and XR600R suspension setup.

I'm combining the two and building a beast. ?

Here's my plan.

Swap the dual carb setup, the head, airbox, cams, timing chain, valve cover, decompression setup, right engine side cover and all the kickstart parts from my '85 XL600R.

The dual carbs and airbox fits by using the rear shock from a '87 XR600R with it's remote reservoir and smaller diameter. The remote reservoir will mount in the XL's empty battery box.

I have already swapped on the XL's 1/8" larger header and XL Supertrapp exhaust. It will be getting wrapped. It is a direct swap for a XR

L header. I still have a spare XL header too. ?

I need to find out if second gear from the XL will fit or if I should just use NX parts. I also need to research adding the kickstart and head swap.

I will be tearing down the engines very soon.

Are there any other good parts I should swapfrom the XL like ignition or such?

Any good links for the second gear repairs, a factory service manual pdf or any other input would be great.

[MentalGuru]

Other plans include a 103mm big bore kit, ported dual carb head, a big cam, 9mm headbolts, new valves and springs.

My main question is about the trans parts swapping. I would want to use the XL600R 2nd gear with the rest being XR650L gears. If not I'll research the NX 2nd gear swap.

Your input would be great.

Thanks ?

[heart_of_darkness]

Fun project. I'm slowly building something very similar.

-I'm pretty sure that the 650L, XL600, and XR600 all have the same second gear ratio. The NX second gear is slightly deeper, which lessens the gear spacing with the 650L's deeper first.

-research ignitions. The xl600 runs a magneto style ignition like the xr600 and most traditional dirt bikes. the 650L has a three phase stator and runs the ignition off the battery. I've heard it suggested that the XR600s have a more aggressive timing curve; if so, best power would be to use the xl600's stator and wiring combined with an xr600r CDI.

-research timing chain widths. XL600s are thicker, therefore presumably stronger, and if so therefore more desireable to use.

-look for an air box from a dual carb xr600r, which won't have wasted space for a battery moulded into the right side. It will give you a larger air filter. I think it may work better with the xr650l left side number plate panel.

-look into a custom longer hose for the rear shock reservoir which would let you mount the reservoir in the normal position on the frame rail.

-the 650l cylinder will already have 9mm head bolt threads, where the xl600 cylinder will need all holes rethreaded. I guess the dual carb head can be drilled for the larger head bolts and alignment dowls, but I haven't heard of anyone doing it.

-you'll need a piston which matches the 650'L's stroke length, not an xl600 piston.