BSA a10 650 smoking

[TYJ105]

Hi there I have a 1959 650 bsa a10 and upon startup it is smoky it used to smoke  really bad and wouldn’t stop until I cleaned the left cylinder exhaust the bike had a full engine rebuild and then sat for 13 years now it doesn’t smoke much but upon startup it smokes and burns oil then after about a minute it all disappears a week ago when I was going to start it I couldn’t start it because the plugs were getting covered in oil but now it’s starting fine just with the bit of smoke on startup any idea on what it could be

[muskrat]

G'day TYJ105 
I'd say after 13 years the rings are letting the oil past until they heat up and seal.
Cheers
Now get over to intros and give us your story.

[TYJ105]

I was maybe thinking that as after it was rebuilt it wasn’t ridden much and when it was ridden it was fine no smoke at all or maybe a little bit without burning any oil from now on I’m just going to keep starting it every few days and ride it and see what it does

[Triton Thrasher]

Oil draining down from the tank into the crankcase while parked.

Maybe.

[Colsbeeza]

Welcome TY, .
Likely rings stuck as Muskrat said. To check TT's (Triton Thrasher) post, drain the sump and measure the volume caught. It should be less than 150mls. If so, you may have to empty the sump before each ride.
Col

[Worty]

Welcome TY, .
Likely rings stuck as Muskrat said. To check TT's (Triton Thrasher) post, drain the sump and measure the volume caught. It should be less than 150mls. If so, you may have to empty the sump before each ride.
Col

Or fit a tap on the feed

....... and tell it to stop - smoking is very bad for you

[Slymo]

Id rather make clouds of smoke than deal with a seizure due to forgetting to turn on the feed tap.

[Worty]

Id rather make clouds of smoke than deal with a seizure due to forgetting to turn on the feed tap.

Disclaimer - if you've a poor memory, DON'T fit a tap on the feed (unless it's one of those fancy ones that attaches to the maggie cut out)

[BSA500]

The cut out taps work a treat

[limeyrob]

This subject is annoying me. I recently rebuilt the bottom end and fitted a new wet sump ball, spring and re-seated the ball. I flattened the oil pump joint.  So the damn thing wet sumps, not huge but enough to smoke for a few mins after not running for 2 weeks.  I've had clapped out engines do better than this so its very frustrating.

[Worty]

This subject is annoying me. I recently rebuilt the bottom end and fitted a new wet sump ball, spring and re-seated the ball. I flattened the oil pump joint.  So the damn thing wet sumps, not huge but enough to smoke for a few mins after not running for 2 weeks.  I've had clapped out engines do better than this so its very frustrating.

Alternatively, you could always fit a cut out tap and go on a memory improvement course

[limeyrob]

"Memory improvement course" Pah, I'm off to the "early onset" diagnosis course

[Swarfcut]

 Final piece of the jigsaw is the oilpump itself. A standard pump has no seal on the drive spindle driving gear shaft, so this is a path for oil to enter the oilpump cavity and from there to the sump. Late A65 pumps had a puny O ring seal in a vain attempt to hold back the oil on standing.

 Sure a new pump MAY effect a cure, but as a design the system behaves well enough when a bike is used as intended way back, as everyday transport. It is only when left standing that wet sumping becomes an irritation to some, end of the world to others.

 Save you money on fringe medicine Rob, invest it in a new pump......or a tap and a big reminder sign.

 Expect smoke anyway from an old sleeper. Chances are rings and bores need to renew their intimate relationships. Silencers may also have a fair amount of accumulated oil deposits. Easy cure for all these maladies is to get some miles in....

 Swarfy.

[limeyrob]

I'm inclined to agree. Its only 5 mins smoke after 2 weeks standing so I can live with that, its just frustrating after the new ball, spring, seat and pump lapping

[bikerboy]

 I recently rebuilt the bottom end and fitted a new wet sump ball, spring and re-seated the ball.
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Hi limey, I normally buy two balls, heat up the crankcase and then give the ball a hard whack to seat it with a wide punch. I then us the new ball to actually fit to the bike ie: the one I have not whacked damned hard lol