breather pipes?

[emacklin]

things are hard enough! <br />

<br /><br />Tell me about it. <br /><br />Hey, if anyone knows a good reason why these ports (I'm assuming we're talking about the ports coming out of the cylinder immediately below the carbs (on a superhawk)) would just keep dumping oil out?<br /><br />Someone I met said that they were to keep oil from building up too much on the top of the pistons, but a Honda Bike shop i stopped at simply ran a single tube, connecting the ports with no outlet. Effectively blocking them up.<br /><br />Sometime later, one of my pistons holed out.<br /><br />I'm not sure if they're coincidental or not...

[kustommusic]

Eric, I am just about positive on my '67 the two pipes were connected to each other and didn't have a Y tube. I assumed it was a factory set-up,it looked stock to me. I just can't believe this had anything to do with the piston failing. It sounds to me like you are on the right track when you look at the ignition system and fuel supply to solve the miss problem you had initially. Steve Greer

[emacklin]

That's good to know, Steve. Thanks.<br /><br />Does anyone have any idea why these breather pipes would be spewing oil out? The whole rig was pretty dry for the first 400 miles or so, then started kicking fresh oil back at me and the engine. <br /><br />Ruined a good pair of jeans.<br /><br />Or improved them... I'm not sure..<br /><br />HOLY CRAP!<br /><br /> What if it wasn't those ports?! I never questioned it before, but now that I think about it, the plastic bottle that I rigged up never caught any oil!<br />I assumed it was because one of the tubes was split near the cylinder, and it must have been leaking out before it hit the bottle,<br /><br /> BUT what if the oil had been coming from the breather up on top of the head that whole time?!<br /><br />Jeez... ok. <br /><br />That has to be it.<br /><br />no wait...<br /><br />It was dry for a day after the cat at the bike shop plugged 'em up.<br /><br />although... Someone mentioned vacuum tubes? could it be that when these ports were stopped up, they created a vacuum in the cylinder?<br /><br />That would explain why the oil stopped coming out from the breather on top...<br /><br />Or, I could stop guessing how a motorcycle works, and read a friggin book.<br /><br />Sorry kids. Thanks.<br /><br />oh man this is obnoxious.

[kustommusic]

Eric, I am feeling like you are making this harder than it is! I'm thinking Load Mouse thought you had blown a head gasket, that could account for the spewing of stuff. Especially if the piston holed out too(which it did). I do know for certain if you have a hole in a piston by running the engine it will create a pressure in the crankcase. Normally I would think it would send gook out the breather. But admittedly I'm used to working on cars not bikes. Another thought, If the head gasket went away first that would cause the enging to run on one cylinder. But now you have me thinking too much. If you just rebuild whats broke it should work,,,,,,,,,right? Good Luck (really) Steve Greer

[FireBob]

My bike is set up just like Loud Mouse said, except no &quot;y&quot;. Both tubes run into the air filter left side. Good luck, fix it and forget it . . .

[LOUD MOUSE]

That will work. Actually you may find a small tube at the front of both air filters and a larger one at the right. The large one is for the head vent and the two smaller ones were used on the CB72 250cc engine with the Power Jet carbs. A tube was run from each Power Jet to the air filter so clean air would be allowed when the carb was wide open. ............LM