what if my breather hose wasn't connected

[Guest]

So I've had many issues with my bike since september. Namely. . . http://www.thegsresources.com/_forum...d.php?t=116318

HOWEVER today, while getting under the tank for the first time since the early fall I noticed the breather hose that connects from the top of the carbs to the (air cleaner)??, well , that thick black hose that runs straight down the middle of that area was disconnected to air cleaner area. Could this be the culprit of all my troubles. WHAT WOULD THE SYMPTOMS BE if this isn't connected as i discovered? I'm currently charging my battery now and will try turning her over now that the hose is connected.

Help appreciated

thanks

[chuckycheese]

Hose

That's not an uncommon occurrence and it wouldn't cause any problems you'd ever notice by riding it. You would probably notice a small bit of oil gathering in the area but, normally, it wouldn't be significant. With some bikes, it makes more of a mess than with others. I had a HD FXRS and the 'blow by' was pretty considerable. With my current bike(s), there's not much.

[maro]

dayum. I was hoping you were going to tell me all my problems are solved. LOL.. thanks for the reply

[chuckycheese]

Yep

dayum. I was hoping you were going to tell me all my problems are solved. LOL.. thanks for the reply

I understand completely....I've asked questions with the same hope in mind. Good luck; you'll get it all figured out, for sure!:-D

By the way, I looked at your previous message and agree that a carb overhaul and valve adjustment will likely solve most, if not all, of your problems. It's not at all hard to do and you can get scads of great information here on the forum.

[Smokinapankake]

I once tried connecting the breather hoses off both sides of my GPz 750 motor...no difference in performance at all. It had breathers on both left and right banks of cylinders, connecting into a T, then routing through some wierd canister valve and into the airbox. Connected both sides together and plugged the crankcase connection. No difference.

[chef1366]

You're only gonna make a mess. No performance difference.

[maro]

Well, Looks like I'll be doing my carb cleanup after all. I've never done this. I will be using the guide found here on the site. Any tips on pulling the carbs?
thanks ya'll

[slowride]

I was wondering about the breather hose also. I was cleaning my airbox (1981 GS850G) and I was concerned about getting all the rust out of the part where the breather hose is connected. I think I did get it all out but should I be concerned if tiny particles make their way to the engine (or is air not drawn from the airbox to the engine through that hose)? What is the purpose of the breather hose?

[Steve]

What is the purpose of the breather hose?

The purpose of the breather hose is to direct the vapors that have gathered in the crankcase through the engine to be burned.

The vapors are there due to blow-by, which is a normal by-product of an internal combustion engine. There are gaps in the piston rings, so there will be some leakage. The leakage that makes it past the rings ends up in the crankcase. If the crankcase is not vented, it will build up pressure, causing other problems. Way back in the "old days", vehicles merely had a tube that lead from the valve cover down below the engine. It was open to the atmosphere, and the motion of the car would create a vacuum, which would draw the vapors out of the crankcase. These vapors would then condense and contribute to the oil slick in the center of the lane.

The EPA has decided that this arrangement was not environmentally friendly, so manufacturers started re-routing the breather hose back to the intake system, usually near the air filter. To assure venting under acceptable conditions and prevent venting under unacceptable conditions, a valve was inserted to assure Positive Crankcase Ventilation (PCV). Evidently our motorcycle engines are not in need of a PCV device, but the breather hose is there to vent the crankcase into the airbox on the premise of maintaining a cleaner environment.

Unless you have a serious problem with your pistons and rings, there should not be enough blow-by introduced into the intake mixture to affect performance on a street bike. However, if you are building a race bike, you will only want as much fresh air as you can get going through the engine.


.

[slowride]

Thank You Steve. Great explanation. Now I understand how oil may get into the breather hose.

[DanTheMan]

I once tried connecting the breather hoses off both sides of my GPz 750 motor...no difference in performance at all. It had breathers on both left and right banks of cylinders, connecting into a T, then routing through some wierd canister valve and into the airbox. Connected both sides together and plugged the crankcase connection. No difference.

By plugging the crankcase connection, it should have caused problems. You need to have a breather connection of one sort or another, otherwise you'll have excessive pressure in your crankcase, and that will blow out seals in other areas, pushing oil vapors out where they shouldn't be......

[Smokinapankake]

Don't know if that contributed to my weeping camshaft seals, but it may have. I didn't leave the crankcase vent plugged for more than a few hours, so I doubt there were any real effects...Interesting thread, however.

[Steve]

Thank You Steve. Great explanation. Now I understand how oil may get into the breather hose.

You are quite welcome. :-D

I feel that is part of my purpose on the board. 8-[


.

[iva]

Thank god for the GS Resource

and for your informative responses everyone...

I'm down at my 750 as we speak (well close enough), taking the air box out to install some new pod filters. Had a minor panic attack about not having anywhere for the breather hose to go, and low and behold, once again, the answer lies with you guys. so thank you......