300ex compatibility

[hondazilla]

i have a bare frame from a 300ex i picked up and a cr 500 my plans are to make a honda quadzilla and i was wondering if anyone knows the size differance in 250r and 300ex swingarm and a-arm mounts. so if you have a 250r i was wondering if some one could tell me the distance between inner and outer edges of the mounts on the upper and lower arms. i have a 250r 3 wheeler and believe the swingarm to be the same so i can referance off that for the rear any help would be appreciated thanks

[DirtDemon]

I have a CR500 powered TRX 250R. The ATC swingarm is the same as the 86-87 250R's. I will measure the a-arms on mine and let you know. What year is the motor you have?

[hondazilla]

i have a 1992 cr500 that im gonna pull the motor out of. how did the 500 fit in the 250 r frame that looks mean. i was gonna go with a 250 r frame and may still if i cant do the things i want with the 300ex. how did the pipe workout is that the 500 pipe or 250 i was worried about needing to make one.

[DirtDemon]

It is the CR500 pipe, I cut it and twisted it to fit in the frame, it seems to work ok. The motor fit pretty easy, I have an '86 motor so it has a 15mm hole in the rear of the case, so it fits on the swingarm bolt. The newer motors have a 17mm hole and would have the hole reamed out enough to put in a 15mm i.d. bushing so that it can mount to the swingarm. Or you can make a bracket and not mount to the swingarm, but you have to keep the sprocket as close to the pivot as possible and keep it lined up with the lenght of the swingarm in order to keep from having chain problems. The 250R a-arms are mounted 25cm(about 9.75") from the inside edge of the rear side of the rear bracket to the inside edge of the front side of the front bracket. The brackets are 5cm(about 2") wide on inside edge to inside edge. You might want to check out this thread cr500 in a 250r frame - E2S There some good pics and info that you may find helpful.