The first YSR was just a rolling chassis.
The rolling chassis got a '86 CR80 motor. I had to fabricate the intake manifold to go from the cylinder to the carburetor. Click Here for those pictures
The YSR/CR80 got the "Franken-pipe" treatment.
The YSR/CR80's progress was put on hold to develop the next YSR member of the garage.
I picked up another YSR with a '91 YZ125 motor in it from a friend. He kept braking the motor mounts in it, so he turned his '03 YZ250F into a super-retard, I mean motard, and sold the YSR to me. I fixed the engine mounting problem and put a TZ125 pipe on it removing the "frankenpipe" he made out of the stock YZ pipe. I trimmed up the lower cowling so it would fit with the TZ pipe installed, he never ran the lower because it wouldn't go on with his "hacked" stock YZ pipe.
Project YZR125 "act 1"
125cc on left - 80cc on right
80cc in back - 125cc in front
80cc on left - 125cc on right
125cc in front - 80cc in left rear
CLICK HERE for pictures of the 125cc with the TZ pipe installed
I ran the YSR/YZ125 at Hallett for a couple of lapping days. The last day at the track the motor finally gave up it's ghost. The connecting rod became a two-piece unit in the middle of turn 5 at around 10,000 rpm with catastrophic results (for pictures click link below), but I managed to get in a good string of 1:35's/1:36's with a best in the mid 1:34's before it turned into schrapnel ending my day.
After the connecting rod failure I decided to continue with the 125cc size motors and came across a stock '01 YZ125 engine kit (all electrics, carb, throttle assembly & cable, radiators, pipe & silencer, clutch lever & cable). It just needed a few modifications to make it ready for roadrace use.