Blew the Motah today o.O

GoldenMotor.com

Cylon

Member
Jun 26, 2015
346
9
18
Maine
Today my wife was riding her bike to work about 15 miles away and her engine seized up. Was a pain in the ass to pull the motor apart, the metal was all melted together.

Swapping the motor out for a new one tonight when I get out of work at midnight.

I estimate it ran for about 850 miles before the failure. Mixing at 32:1 and it was stock. I plan on adding a 6.0 cc head and a banana pipe for the next motor tonight. I hope that should keep it cooler.

I have a spare reed somewhere too but last time I tried it I didn't like it on my bike.

 

Cylon

Member
Jun 26, 2015
346
9
18
Maine
Wrist pin bearing was okay. The wrist pin itself had the bearing melted into it then looks like the piston dome smacked the transfer port.
 

Cylon

Member
Jun 26, 2015
346
9
18
Maine
Nope I'm building an exhaust for it tomorrow I get out of work at midnight so I'll probley spend my night listening to music having a few beers and replace that motor with a new one. I'm just bolting a whole new engine in there shouldn't take to long.
 

Nashville Kat

Well-Known Member
Apr 20, 2009
1,501
55
48
Jacksonville, Florida
Keeping things stock has some advantages I think- just bolt the stuff on a new motor and go. I always keep in my mind the Chinese Junk- the little boats that have been a way of life in the Oceanic Asian regions for centuries. It's not that the motors are "junk"- it's that we're really dealing with something conceived to have a great practical value first, for teaming millions we've been fond of dropping gasoline on.
 

Cylon

Member
Jun 26, 2015
346
9
18
Maine
Yep drained the gas and it was blue just mixed 2 gallons of 32:1 last weekend. All the other bikes have been fine on that gas.

She said it slowly just died then locked up the rear wheel.
 

maniac57

Old, Fat, and still faster than you
Oct 8, 2011
4,484
22
0
memphis Tn
Sure sounds like one too. Most likely a cylinder plating failure then.
I hear there have been a rash of jugs with bad spots lately, and I recently saw one myself with a dime sized defect, luckily BEFORE using it!
 
Could have been a bad crankshaft oil seal. This will cause a super lean mixture due to air being partially sucked in through the bad seal instead of the carburetor thus leaning out the mixture. I've repaired several 2 stroke motorcycles that befell this fate. The best thing to do if you have a means to do it is to have the bottom end pressure/vacuum tested. It also could have a splitline seal failure or a crack in the crankcase. A quick and dirty way to check for a bad oil seal is to spray starting fluid around the seal area, if your engine picks up a lot of RPM you probably have a bad oil seal.
 
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Cylon

Member
Jun 26, 2015
346
9
18
Maine
Could have been a bad crankshaft oil seal. This will cause a super lean mixture due to air being partially sucked in through the bad seal instead of the carburetor thus leaning out the mixture. I've repaired several 2 stroke motorcycles that befell this fate. The best thing to do if you have a means to do it is to have the bottom end pressure/vacuum tested. It also could have a splitline seal failure or a crack in the crankcase. A quick and dirty way to check for a bad oil seal is to spray starting fluid around the seal area, if your engine picks up a lot of RPM you probably have a bad oil seal.
i just ordered a new motor for 130 bucks problem solved.