engine swap

[hovis]

Hi all
I am looking to replace the engine in my old r45 with an r80 engine. I have found a complete engine from a 92 registered bike . My question is can I revert the r80 back to points ignition and are the charging systems compatible
Cheers Hovis

 

[newbuild100]

Not sure re the engine swap, and this may not help much but years ago, Im pretty sure we changed the electronic ignition back to points on an R1oo. (that was continuously having probs with the canister.)
This was done after BMW motorrad said it wasnt possible. !!!!!!!!!

 

[Rob Farmer]

What year is the R45? if it's pre 1980 you will have serious problems matching the clutch to the gearbox.

If you have the bean can fitted to the R80 engine I'd buy a Lucas dab 400 ignition module and turn the whole thing over to electronic ignition, however the simplest option is to buy a 1980 bean can, this will have points fitted instead of the electronic pick up.

The electronic bean cans worth around £50 if you need to recoup some of your money.

You will also need a final drive to match the R80 along with another speedo to match your new final drive

 

[JJH]

I think Motorworks do a kit with 650 barrels and pistons to change a 450 to a 650 might be a handier job JJH

 

[hovis]

The bike is a 1980 reg but the chassis number says built 1979. what is the trouble matching the clutch? I have the option of the complete bike less the frame.

 

[Rob Farmer]

This is the realoem page for the R45 Clutches http://www.realoem.com/bmw/partgrp.do?model=0351&mospid=51892&hg=21&fg=05

if you look at the dates for the clutches they changed them in 1980. Yours will be the bottom one. The gearbox input shaft and drive side casing are different to the later gearboxes.

If you have the option of the later gearbox as well that will make things a lot easier for you.

http://www.realoem.com/bmw/showparts.do?model=0351&mospid=51892&btnr=21_0068&hg=21&fg=05