Oil blow by?

[Dynamohum]

Not really an oil issue but that’s the end result. A thin mist of oil tends to cover the lower end of just about everything aft of the motor, especially the inside and underside of the bags. Now I recall this a bit on my previous 82 but nothing to this extent. Looking thru the motor I can’t see any area that’s seeping that might be the cause and the motor @ 39,051 seems to be in perfect shape. Doesn’t burn oil and barely uses any. I added a quart after nearly 4,000 miles as the dipstick showed it to be low. I’m using 10/40 Amsoil as I do and have on all my bikes over the years. Is there an oil vent tube somewhere that could be routed wrong or plugged? Could a too rich motor be the culprit? After a run, four headers read around 175-180. Two read about 15 degrees lower. My mileage is in the mid 30s. To confirm, the checkered area on the dipstick is where I want the oil level to be right? It’s been nearly 7 years since I had a 79 and over 10 years since I had an 82.

[Larry Zimmer]

Just a wild hair---- Could there be anything coming from the vapor condensation 'bottle' that is located up under the rear fender? That bottle collects any condesed vapors from the carb that don't get ucked back into the engine. (Crankcase vent vapor.) That bottle tends to get brittle and crack. And/or, it's mount breaks and it cracks. Just a thought o something to check given that you said everything aft of the engine. Good luck with this witch hunt.

[CBX-tras]

About your oil.......I'm a big fan of synthetics in almost any motor.

But the CBX starter drive (buried deep in the motor) only has 3 rollers to engage. Synthetics are too slippery for them to engage and stay engaged.
If you are experiencing starter slippage or non-engagement, switch back to a dinosaur oil and that problem will go away.

It's an expensive repair if it fails, totally.

[CBX-tras]

Stock alternator or Denso/Kawasaki conversion?

[Dynamohum]

Just a wild hair---- Could there be anything coming from the vapor condensation 'bottle' that is located up under the rear fender? That bottle collects any condesed vapors from the carb that don't get ucked back into the engine. (Crankcase vent vapor.) That bottle tends to get brittle and crack. And/or, it's mount breaks and it cracks. Just a thought o something to check given that you said everything aft of the engine. Good luck with this witch hunt.

When the shock was replaced I noticed an empty plastic ‘bulb’ near the shock with hoses coming out of each end. Is that what the book says is the crankcase breather storage tank? I thought it had something to do with the OEM shock. To replace it looks very hard to do. My hands are kinda big. Is that it?

[Dynamohum]

Stock alternator or Denso/Kawasaki conversion?

Stock. My previous 82 had starter issues after 80-90,000 miles and then only if I hadn’t started it in over a week. Daily morning startups on tour were no problem. Mine currently has under 40,000 miles and the starter engages perfectly even after a couple weeks of not starting it.

[CBX-tras]

Consider yourself lucky with using synthetics.

I've known guys that sold their CBX because they didn't want to go to the trouble of fixing the starter drive.

I see synthetic oil in a CBX like how long you can hold on to a hand grenade with the pin out.

[Larry Zimmer]

I've heard both on the synthetic. Some without ever an issue. Others with starter spin on the first crankcase full. As with J.R., I'd stay with the non-syn. Ever try to push start a CBX by yourself?!? There's plenty good stuff of the 'regular' out there. As Kevin Cameron once said about oil brands and types, 90% of the thing about it is just to have enough in the crankcase.

[Dynamohum]

I've heard both on the synthetic. Some without ever an issue. Others with starter spin on the first crankcase full. As with J.R., I'd stay with the non-syn. Ever try to push start a CBX by yourself?!? There's plenty good stuff of the 'regular' out there. As Kevin Cameron once said about oil brands and types, 90% of the thing about it is just to have enough in the crankcase.

Larry, maybe you missed my response above copied below,

When the shock was replaced I noticed an empty plastic ‘bulb’ near the shock with hoses coming out of each end. Is that what the book says is the crankcase breather storage tank? I thought it had something to do with the OEM shock. To replace it looks very hard to do. My hands are kinda big. Is that it?

[Larry Zimmer]

Mine was cracked at the mounting. Things were a bit meessy in that entire area. Not much in the 'bulb' itself -- just general oil all around. I repaired the bulb with fiberglas and anchored it with some steel strap. I found and did all this when I was replacing the shock. So, everything was out of the back end. Don't know way other way to access the thing. I would not have known about the crack and oil mess if I had not removed the air bag to install the Progressive. Unfortunately, I didn't take any photos.
My original mounts were so cracked that the bulb was staying in place just being held by the hose and overall location.. You won't get your hands in there to do anything unless you remove the wheel and shock. Assuming the bulb is cracked, that can be repaired with fiberglas. Mounting is a matter of inventiveness. Note: one hose comes from the air box on the back of the carbs; the other is a drain hose that terminates on the right side of the frame behind the centerstand mount. It should have a plug in it. The plug and bulb repair are necessary to prevent the engine from sucking outside air. Hope this all helps.

P.S. On the oil comment I was addressing the post by cbx-tras about oil. Nothing to do with your problem. Sorry for any confusion there.

[daves79x]

I'd first thoroughly clean the bike and especially the area mentioned. For sure investigate the oil catch tank for damage. You can change it without removing a bunch of stuff, but it's not easy. If the mounting tab is just broken, the hoses will hold it in place. Then see what gets oily first. I suspect your oil is coming from somewhere else. Possibly from the sump cover or perhaps an about-to-fail oil line.

Have to say, synthetic or not, 4000-plus miles is too long without an oil change on an air-cooled engine, especially a CBX.


Dave