Anyone ever own a 1976 Honda MR 175??

[Yamaha_Rules69]

I own a 1976 Honda MR 175 oldschool motocross bike, bought it for $25 a few years ago! What a steal!! It was a good bike WHEN it ran. It has new coils in it, new points, and has great blue spark. The only problem with it is the flywheel. Every time it gets fixed, the same thing happens. The little sodder key that holds the flywheel in place always manages to come loose somehow, or something happens, causing the keyway in the flywheel to crack. It has done this 3 times now, once to the original, and two times to a diffrent flywheel we bought. We had it welded, thinking it was going to work, and it happened again. Anyone else ever own one of these bikes? Does anyone have a solution that may solve this problem? Let me know. Thanx.

[Kilborg]

You should not be shearing keys like that. Properly mount the flywheel, and torque it to spec

[Honda300ex]

We have 2 76 Mt250s One my dad bought new and we are rebuildin the motor right now, Then we have another that we got in a trade and the guy gave us a side cover for a 125.. Need it?

[Honda300ex]

The one my dad bought new does the same thing as urs.. we are tearing it down and puting a new crank in it

[Yamaha_Rules69]

do you know if the 125 side cover will fit a 175? I dont know if i want to stick any more money into this thing..

[Honda300ex]

woops.. i thought you had a 125.. I could get some pics if you wanted. In a few days my camera should be in

[TimSr]

I had a similar problem with my TriZ shearing off keys. Last time, I put a bunch of Loctite on the flywheel where it contacts the crank, and torqued it down with the air impact, and havent had a problem yet. However after I did my "fix" somebody posted baout how they used valve lapping compound on the flywheel and shaft, and when you got finished you had such good surface contact, that they didnt even use the woodruff key. Id stilkl use the key, but his fix makes sense to me.