Motorcycle Repair: smoke from exhaust, air fuel mixture, gasoline consumption

Question
Hi! I have a 1991 Yamaha Super tenere. I've had it for 2 years and I don't think it is in a good condition. When I bought it, it had a hole in a gasket on carburetor. I fixed it, but there's still smoke coming from exhaust. Black smoke. It also uses a lot of oil. About 2-3 dcl per 1000 km. Gasoline consumption is also high. Above 7l/100km. Are these problems connected? Can I fix it, or is my bike...
Hope to hear from you
thanks
aljosa

Answer
Hi Aljosa,

Perform cylinder compression and leak-down tests to know the condition of the engine.

Black smoke indicates a excessively rich air-fuel mixture.

Oil consumption up to a quart per 1,000 miles is considered normal with some manufacturers.

Worn needle jets contribute to increased fuel consumption. Rich A/F mix also causes high consumption.

You can fix it. Start with a tune-up. Tune the carburetor and repair worn parts as necessary.

Respectfully,
Mark Shively