The 1980 sachs that I bought a few weeks ago ran about 25-27mph as I got it. After a few minutes the bike had a loss of power and would only go 5mph up a slight incline. It would still reach 30mph downhill. I thought that old rings might have been to blame odometer shows 4000 mi
When I removed the cylinder it looked like this
I ordered new rings, but they haven't arrived yet.
I also wanted to have the cylinder honed out so I removed it. This cylinder is very narrow and I couldn't find anyone with a small enough hone. I'm going to check the bike shop where I used to work because they had some ones that I think will fit.
Now this is the wierd part. In the exhaust port there were some really big drops of metal.. kind of like someone dripped solder inside....but why would anyone solder the exhaust port?
So I thought about it a little more, and thought that maybe someone had siezed the engine so bad that the piston melted and dripped down the exhaust port. But if this did happen, it obviously wasn't with the current piston, because that one seems to be in ok shape (except for the light scoring). And also there seems to be no aluminum smearing on the cylinder.. just light scuffing on both the cylinder and piston
Another possibility is that the weld was part of the engine construction. But another sachs owner said that his port was smooth and circular. So maybe this is just a defect in my engine.
I don't know... I can't really think of any good reason that the exhaust port looks like it does. In the picture below you can kind of see what I mean. I have sanded it down a little, but in the case that it is holding my cylinder together, I don't want the weld to break.
Also this is a sachs 505 engine which has a one piece head and cylinder.