Smoke on start up...

What side is it smoking from, it could be wet sumping. 

If you stop and think about what the possible sources of the smoke are you can come up with only a couple.....

Rings

Guides

It will be a process of eliminations until the correction is made.

Which side is the smoke coming from?

p.s. When you park up your bike are you using the sidestand or centerstand?

I have read here that when on the sidestand  oil can gravity to the guides on the low side???

Mike

Drain the sump before starting, if the smoking does not happen then carry on draining the sump before each riding day or leave the surplus oil in the sump and live with the smoke.

Your engine may be displaying the classic signs of wet-sumping due to a worn oil pump.

If you Commando has covered more than 50,000 miles then the chances are that the oil pump is worn internally and in need of a service. The original Dominator  pump was designed to last 100,000 miles but with the bigger engines came the double speed gearing which of course wears the pump out much quicker.

Hello It's Not Just  Norton,s  That Smoke On start up  many Diesel engines and petrol engines  do smoke on start up  as an engine is left for some time  there is a build-up of oil around the rings  and valves areas  and this after startup then burns off  when the engine is warming up  So nothing much to worry about,  just ride and enjoy    yours   Anna J