Mix n Match Shimano Crank Arms?

Does anyone know if a 6800 left crank arm will work fine with a 6600 drive side?

Seems like it should be ok.

Nope

You’re probably right. Suck it and see.

Yes, it will.

edit depends on bb width actually. The shorter preload cap that screws in can sometimes be an issue.

The only issue i can imagine might be s slightly different width on the lh crank arm. The steel axle spline looks pretty identical on all road cranks…

I’ll probably take the plunge and find out.

I’ll report back so that when nobody ever wants to know this, they can find it here.

If you have the bits, 7800/7900/9000 compatibility would be good too.
Ive done searches for this before with no luck.

yeah pretty much all of the shimano cranks will work with each other, all of the DA ones do, can confirm.