I've got an XR80 that I've been using as pitbike/yard bike to eff around on. It's lost compression (~70) and I'm looking at a couple hundred to order a new piston kit, gaskets, rebuild, etc... Don't really wanna spend it on the bike. IF I could find a working 100 motor (and it'd fit) for a couple hundred, I'd consider that route. Anyone know if this swap would work? Otherwise, if anyone has any interest in the bike, I could bring it to Summit next weekend. PM me.
The 100 motor should drop right in as well as use the same exhaust. I can't speak to the electronics or carb, but they should be compatible. The difference between the 100's and 80's is the swingarm, everything else should be compatible.
Thanks. I'm looking but not too many complete motors out there. Really don't wanna shitcan the thing... it's really been a fun little neighborhood terrorizer!
Can anyone confirm the stock bore size of this bike? I'm searching but I'm getting conflicting #s. I THINK it's 47.5mm, but I've seen 45.5mm, 46mm... If it's 47.5, can I shoehorn in a 48mm piston without boring out the cylinder? Seems 47.5 is an odd size... (*disclaimer: I'm not much of a mechanic so I apologize for the dumbdumb questions!)
47.5mm bore 45mm stroke. You would still need to bore it to fit a 48mm piston. Also the xr80 has a 13mm pin. The xr100 has a 14 mm pin.
the 100 has a 24 mm carb as well. the intake body on the head different as well. the xr 80 carb has bolts that come from the carb, the 100 has bolts that come from the intake. the xr 100 head is different as well. stock 100 is 9.1:1 and 80 is 9.5:1