I bought a bike from a guy it's a 79 with a broken chain and he said he would have to do a conversion because he couldn't find the original chain. Well after that I went to ride it home and the rear wheel started wobbling back and forth, the bearings had gone out but the guy said he rode it for like 30 miles that morning to test out the new chain. I'm about to put new bearings on it but I was wondering if it's a possibility that the new chain threw the bearings off, etc. it's a 32 year old bike and everything that went wrong with it was origianl with only 17k miles
I think the seller has been buttering your bread a little.
Always give year, make, engine size and model # when asking questions. We need all of that info to give an informed answer. Japanese bikes of that era used 3 bearings in the rear wheel. 2 bearings in the wheel hub and one bearing in the sprocket's flange, with a spacer between the sprocket flange and the wheel hub. If that spacer was not installed, that could cause the bearings to prematurely fail. Unless the chain was adjusted improperly (to tight) it's unlikely the bearings would ware out from installing a new chain. Before removing the rear wheel, check the chain slack to see if the previous owner installed the chain properly.
Yes, an improperly installed chain (too tight) can mess up the wheel bearings, but unlikely in 30 miles. More likely, the bearings were already messed up. It is an old bike and you have no way of knowing when the last time those bearings have seen the light of day for maintenance. Good clue here to look into all of the other critical components of the bike before putting a lot of miles on it.
Get yourself a manual if you don't have one and pull it apart yourself. No conversion was necessary, chains are widely available. A new chain will not trash bearings. They may have been on the way out - but not likely at 17k unless it was stored in a swamp. Pull, clean and grease the swingarm bearings, too. That grease in there is now hard as a rock and not lubing anything. You should also change the front wheel bearings when you do the rears and at least clean and re-pack the neck bearings.
