1974 125/175 Connecting Rod Woes

I picked up a 1974 175 a week ago that overall is a nice bike. I had planned to rebuild it to use in AHRMA cross country events but have discovered it has a bad rod.

The question is: Can this be fixed or do I now have a 200# pile of parts.

Thanks, Dennis

What is the length of the conrod centre to centre and lets have the other dimensions whilst you have a vernier out...?

Andy

I don't have the engine apart yet but the rod is 94mm from the crank pin to the end of the rod with a 19mm hole in the small end. The rod is 12mm wide at the bottom and 20mm wide at the top.

The motor has a PVL ignition on it and it will run. With the cover off you can see the flywheel moving back and forth laterally, what is supposed to keep it from doing this? It has a full 1mm of play in and out and it has some up and down so crank bearings are needed.

The rod does not seem to have play up and down but you can rock it back and forth. If I read right the piston is supposed to keep it centered but the bearing can be moved side to side. I also makes a lot of noise running.

Sounds more like main bearings than big end bearings.

The rod is piston centered in Husqvarnas so that play is necessary. Most others are crank centered.

That's good to know, still trying to learn Husky stuff after years of Penton/KTMs.

Would the mains be allowing the lateral play? A friend who does all kinds of engines is going to take a look at it. I'll be thrilled if it is just the mains and the rod is OK.

Bad main bearings would give the effect of radial (up & down) play. The noise would likely indicate severe wear on the beaing rollers or balls

mains are a deep rumbling noise and sometimes allow some over rev if they let the seal leak air.

Thanks for the reply's. From other people looking at it, it seems my rod is OK. The lateral movement of the crank seems to be the concern now, will have to get it split apart and see what is up with that.