Bikeguy Joe
Godfather of Motorized Bicycles
We are talking air leaks not oil leaks.
Significant power decrease, no more hills, 3 weeks old
- Thread starter nsxcorvette
- Start date
We are talking air leaks not oil leaks.
biknut
Well-Known Member
Right, but no matter where an air leak might be, oil will come out with the air. So you might ask, what if air is only leaking in. Again, there's no place in the motor where air pressure doesn't go both ways. So oil is always going to be present from any leak.
goofyfoot2001
New Member
ok, so where is the crank seal? can you put a link to gaskets? I'm assuming we're talking about replacing a gasket. I have the black jet 66cc http://www.pistonbikes.com/product-p/1bjet80.htm
biknut
Well-Known Member
There's one behind the magneto rotor, and one behind the pinion gear. They're both different sizes.
If they're leaking you'll notice oil, especially in the magneto compartment. The pinion gear side might not be as obvious because of grease splatter from the gears.
It's still a good idea to check the seals to make sure they're installed properly. You can't see them without taking off the rotor, and the pinion gear.
Bikeguy Joe
Godfather of Motorized Bicycles
...and if you have an air leak around the intake gasket, you will not likely see anything until you remove the intake, and then you may see a faulty gasket, with no oil.
To fix that, just use some seal all or RTV silicone and goober up both sides of the gasket with a light coat and re-install it.
To fix that, just use some seal all or RTV silicone and goober up both sides of the gasket with a light coat and re-install it.
goofyfoot2001
New Member
I had just put a new gasket on the intake but this weekend I'm taking off the carb and cleaning everything and gooping up every seal. FYI I installed the scrappy dog CDI/ignition coil combo and while the bike would stall after idling a few minutes, the bucking going on at low speed when just started seemed stronger. Hoping this will give me a better power band on the top end.
goofyfoot2001
New Member
Biknut "There's one behind the magneto rotor, and one behind the pinion gear. They're both different sizes.
If they're leaking you'll notice oil, especially in the magneto compartment. The pinion gear side might not be as obvious because of grease splatter from the gears."
There is oil in the magneto compartment and I feel air pulsing out at where the wires come out. So I guess maybe compressing is f'd.
If they're leaking you'll notice oil, especially in the magneto compartment. The pinion gear side might not be as obvious because of grease splatter from the gears."
There is oil in the magneto compartment and I feel air pulsing out at where the wires come out. So I guess maybe compressing is f'd.
biknut
Well-Known Member
That's a sure sign the seal is leaking. It's easy to replace it.
goofyfoot2001
New Member
Is there a diagram of the engine online any place? I assume I have to break down they whole engine no?
goofyfoot2001
New Member
I meant to say compression
goofyfoot2001
New Member
Are there other seals than these gaskets? http://www.gasbike.net/bike-motor-part-66cc-gasket-kit.html I guess I'm clueless on what seals you're talking about. Can you throw a link up to the parts please!
mew905
New Member
they're referring to these http://www.gasbike.net/bike-motor-part-seal-loop.html
It only offers the one and as far as I know the bearing it's sealing both on the magneto side and pinion side are both 6202 bearings (so same size, not different). Buy one of these, pull the magneto off (its really easy, I just stick a pair of pliers somewhere to stop the magneto from spinning, then use a ratchet [14mm IIRC] to take the bolt off. Then the magneto will pop off, though it's a strong magnet you will need some force, but not a whole lot), then theres a metal shim right under the magnet. Take that off, and you'll see the black bearing. Total time to replace it... I'd estimate around 10 minutes. However having never needed to replace it before, I dont know if you have to crack the whole case open (which could take an hour or so), in which case buying that gasket set would be good as you'll have to replace ALL the squished gaskets. While you're at it, if you're at that stage, may as well goop all the gaskets with sealer to prevent any air leaks in the future.
It only offers the one and as far as I know the bearing it's sealing both on the magneto side and pinion side are both 6202 bearings (so same size, not different). Buy one of these, pull the magneto off (its really easy, I just stick a pair of pliers somewhere to stop the magneto from spinning, then use a ratchet [14mm IIRC] to take the bolt off. Then the magneto will pop off, though it's a strong magnet you will need some force, but not a whole lot), then theres a metal shim right under the magnet. Take that off, and you'll see the black bearing. Total time to replace it... I'd estimate around 10 minutes. However having never needed to replace it before, I dont know if you have to crack the whole case open (which could take an hour or so), in which case buying that gasket set would be good as you'll have to replace ALL the squished gaskets. While you're at it, if you're at that stage, may as well goop all the gaskets with sealer to prevent any air leaks in the future.