[Mister November]

For Fracks sake, the left cylinder on my 76 CB200 is smoking a lot when she gets really warm, what gives? what might be the problem, and what do I have to do to fix it? By the way the bike has less than 1500 miles, true mileage. Please help, I love this bike and it seems like a serious problem, or could become one. thanks for your help...

 

[scott.v]

What colour is the smoke?? Are both the carbs tuned properly? Have you cleaned them out thoroughly and checked mixture in both cylinders? Running rich in one cylinder will wash oil off the bores and make the problem look worse. If you've done all this the next thing to look at is valve stem seals and piston/ring wear. A cylinder leakdown test will indicate ring wear.

Lucky find with only 1500 miles, but remember it's still over 30 years old!

Scott

 

[Mister November]

the color seems to be white, and gets heavier the hotter the engine, i'll check the carbs, kinda numb-skulled on my part, i do believe the carbs have been running rich, especially on that side, what does smoke color tell you? Thanks for your response...

 

[cb175guy]

Typically white smoke means you are burning oil. If you were very rich the smoke would be a darker color.

check compression

report back your findings. we'll get you through this.

 

[Mister November]

thank you for posting back, what is the easy/cheap way to check compression, and what is the spec i should be hitting?

 

[scott.v]

You should be getting 140-170psi on a hot motor with no more than 25% variance between cylinders. This is as per the Clymer manual. Ride the bike till hot, switch off, leave ignition off and hold throttle wide open. Kick motor over until reading on compression tester stabilises. Then come back and tell us what you find.

Smoke from over-fuelling should be black.

Cheers, Scott