Broken Exhaust Bolt

[Joast]

Hi, I am a new poster from Illinois. I just bought a Schwinn Riverside cruiser with a 2 stroke engine off a facebook ad. The seller knew little about the whole setup, but claimed it was built at a shop when he bought it.
Anyway, when I got it home it looks like one of the 2 exhaust bolts is broken off in the mounting hole in the Cylinder. The exhaust gasket is toast. It is an allen bolt in the other side. Is there any way to fix this or should I just look for a new motor or cylinder? It starts to run when the clutch is dumped but not well and then it dies. All the guy could tell me is that he thought it "might be" an 80cc engine. I should have just walked away, but the whole thing was only $175 and it was rust free with new tires and all the acessories installed. Can anyone give some input on the best option to fix or replace. At least I would like to get some idea what engine this is. Pictures are attached.
Thank you for any responses. John

 

[Greg58]

Welcome to the forum, that looks like a 69cc engine, the 48cc engine has head nuts that needs a 10mm socket to remove. You may be able to get the broken piece out, tap near the edge with a center punch to see if it moves. The reason the stud broke is it doesn't have a rear mount on the muffler in the picture. If it's not flush to use the punch you can drill it center and use an easy out, if you can find a left-hand drill bit the vibration and reverse rotation may back it out.

 

[Greg58]

Warning, the same vibration that broke the muffler will break the fender mounts, there have been a lot of people hurt because of fenders locking up the tire.

 

[Joast]

Thanks for the help. I have the fender issue on my list. They will be removed if I get it running. The muffler exhaust flange is also bent so it will need to be upgraded as well. I have already pulled the muffler.
Thanks for the ideas on the stud removal, if it doesn't work I will just get a cylinder-- if I can figure out what will swap on for this engine. Are there different 69cc cylinders? I have a micrometer ordered if I need to measure the bore etc. Thanks John

 

[Greg58]

They are all fairly interchangeable, the port placement will differ from one supplier to another. If you replace the cylinder I would change the piston and rings also, they’re not that expensive.

 

[Mossy]

These are the new 2018 triple 40 open transfer cylinders... Note the exaust port on some are a 2 port zeda style and the pk wildcat is open no divider... There's the older style with closed transfers 40mm intake. The last one.. if you're going stock replacement piston port...no reed no pipe nothing but what came with it 69cc is the one you want... CDH

Thanks for the help. I have the fender issue on my list. They will be removed if I get it running. The muffler exhaust flange is also bent so it will need to be upgraded as well. I have already pulled the muffler.
Thanks for the ideas on the stud removal, if it doesn't work I will just get a cylinder-- if I can figure out what will swap on for this engine. Are there different 69cc cylinders? I have a micrometer ordered if I need to measure the bore etc. Thanks John

 

[Mossy]

I don't know what happened but these are a few of the cylinders triple 40 / wildcat pk80...

 

[Joast]

Thanks for all the info on the engine. I suspected it was a 69cc, but didn't know how to tell that from a 48cc or one of the 80cc+ by looking at the outside. If it got to the point of buying the cylinder and a piston I would probably just get the whole engine ---then I could at least know what I had and some history of usage. Tonight I got the bolt out with an Irwin spiral screw extractor with drill bit combo from ACE. The included drill bit was not reversed which I thought was strange, but anyway, I am back in business for now to see if it will run. Thanks for the help. John

 

[Greg58]

John if you install a rear mount on the muffler it will take some stress off of the studs.

 

[Joast]

Thanks, I am going to look into that but I am not sure where it will mount on to the downtube.
I was going look online to see what the options are floating around. I don't think this thing ever had one
on the frame before. john

 

[Mossy]

Thanks, I am going to look into that but I am not sure where it will mount on to the downtube.
I was going look online to see what the options are floating around. I don't think this thing ever had one
on the frame before. john

Something like this and run a file over the flange and cylinder to make the surface flat and the Toyota gasket is the best fix for the exaust... The studs fit Vdub beetles....

 

[Joast]

Thanks for the links Mossy! i have the exhaust system roughed on for now just to keep stuff out of the engine. I got a metal gasket that a guy at the mower shop gave me that fits good as best I can tell. Will put on the studs and the brace linked above to hopefully get the stock exhaust more solid.
I have been sidetracked messing with the carb --which was plugged up, but finally got it to fire up and run-- Not running great -but the carb may still have some issues. Gonna have ground it until I can get my flopping rear fender cut down or removed. Also the brake is basically not working, but I think it is just needing adjustment. Thanks Again! for your helpful links and advise. JOhn