Smoky left pot on start up..

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FastFred

FastFred

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Why does my bike do this, it was on the centre stand and only stood for a week. The amount of smoke that belched out of the left cylinder last night was unbelievable and I only rebuilt all the top end and new rings 2000 miles ago? Filled the garage in seconds, could have died holding the twistgrip!

Seems to clear up after a run.
 
Try doing the disable the oil feed line to the head trick as this helps determine if the problem is in the head or pistons.The head can go a long time without oil so do not worry too much.
 
I know that oil fog. Mine was doing this too - but on the right side. I thought most was due to wet sumping because if I drained the sump first it wouldn't do it. I actually had oil droplets on the windshield of my car which was parked behind the bike!

But... it is much improved since I had my cylinder head rebuilt by Leo Goff over the winter. He said 2 of my valve guides were very loose. So much so that one fell out whole (intake left) and another fell out in 2 pieces (exhaust right). So.. did you replace the guides? If the old guides are driven out per the manual without removing the carbon build-up then it is easy for the bores for the guides to lose material and the new guides will be too loose. Oil can pass around the outside of the guide. Leo machines the old guides out (if they don't fall out first) and so avoids that problem. He had to go oversize on the 2 loose guides for me.

Check inside the left exhaust port for oil after letting it stand for a while.
 
Make sure it's not just wet sumping by draining the oil from the sump and putting back in the tank. If it doesn't smoke then, no use worrying about other things. If it still smokes, then on to the rest. I couldn't believe how much mine could smoke when wet sumped, I installed a ball valve in the feed.

Dave
69S
 
My Trixie I recently re-honed re-ringed d/t ring gap smoking my world up to mis firing, did fine immediately after but after 1st week about smokeless she now alternates which side fogs oil on starts ups for a few minutes then clears up. Yesterday, she started smokeless, ahh, then about 20 sec later L side fogs, ugh, for a minute then cleaned for rest of the day. Then left key-light on at work, and waited for Wes on his scooter to show up for a push off and quick start but we left her running to charge and after a couple of minutes hi idle and some blips both pipes began smoking but not the blue/white pure oil but grayish white for a few minutes. Trixie is parked on center stand with crank left near TDC. Head renewed about 8000 miles ago, but I suspect some guide leakage now not rings. After a decade of reading the short intervals of Head leaks I've another standard head to switch out if Combat head get so oily its too much to take again. Intermittent smoking or other faults is a manhood willpower tester to me constantly it seems.
 
You'd think that if it were the result of a wet sump that both cylinders would smoke.

That said; it IS a Norton, so try draining the sump and see.
Or, just kick it through 10 or 15 times to scavenge the sump and see if it smokes less.
 
Trixie changes smoke behavior one day first start to the next. Once started and warmed she's acceptable not noitced. Some time immediate smoke other times I'm grinning in relief for 20 sec then one side or the other smokes badly to almost misfire w/o blips. I will not pump my engine over unless to start d/t the loss of the zn/phos nano pad protection after a turn or two and don't start up unless can get full temp if I can help it. Bad cam lobe/lifter ju ju.

I'd think if intake seals then would be consistence smoking side and get worse as warmed fully. At least Wes and I are of same old school of thought, run it till a show stopper then obvious where to take it from there.
 
FastFred said:
Why does my bike do this, it was on the centre stand and only stood for a week. The amount of smoke that belched out of the left cylinder last night was unbelievable and I only rebuilt all the top end and new rings 2000 miles ago? Filled the garage in seconds, could have died holding the twistgrip!

Seems to clear up after a run.
Click to expand...

Let me guess - this is a 750? maybe a '71? and its wet sumped just enough.

Mick
 
I should have made a picture of the smoke when mine wet sumped. It filled the garage since I had the silencers pointing in there, and the whole house smelled like oil for at least a day. But have not had a problem since draining the sump with starting and now have a valve.

Dave
69S
 
Sometimes the TRIUMPHs smoke too . . .

Smoky left pot on start up..


The Original Dennis ' Stormin Norman ' flying grandfather .
 
If its a Commando could also be ring gap or bore scoring and oil leak inside gasket on that side.
 
Hey Fred,
did you mean that the head was rebiult, and new rings fitted to old pistons.
Was this the first time.?
May be sticky rings. ?
 
Same pistons, new rings, all new guides seals etc. Bike is a '74 850. Will run it tonight and see what happens..
 
DogT said:
Make sure it's not just wet sumping by draining the oil from the sump and putting back in the tank. If it doesn't smoke then, no use worrying about other things. If it still smokes, then on to the rest. I couldn't believe how much mine could smoke when wet sumped, I installed a ball valve in the feed. Dave 69S
Click to expand...


Could you please tell me where you obtained your ball valve from :?:

I would like to fit one to a Dommi :wink:
 
Many have gotten or made up their own power switches in oil valve. At least one, me, has the handle in the way to put foot on peg or kicker w/o turning it on out of the way. Caveman fool simple even someone stealing it will not forget it to ruin their new smokeless booty.
I'm no longer concerned with wet sump as long as oil enough in tank to run a few seconds before sump pump puts twice as much back and leaving. But I am a bit pissed the smoke tends coke chambers and soot up plugs. The weird ness in my current Combat is smoking changes sides on one 1st cold start to the next. A couple days ago smoked on LH in am, then sat till 6 pm stone cold dead battery push off w/o any smoke till rev's on side stand heated up really good then more grayish sooty than blueish white. Commandos mystify me more than women now.
 
Started it tonight, no smoke even though I turned off the ignition the other day before it had finished belching smoke out, work that one out!

Nortons...

Just fettling my flatslides which ticked over better than ever tonight. Dropped needles a notch (raised clip) as they were rich on the plug chop . Test tomorrow.
 
DogT said:
Don't know what size your lines are on the Domi. I took the barbs off my fittings and am using 3/8" hose. A 1/2" pex ball valve will fit fine. Here's what mine looks like.

Smoky left pot on start up..


I'm sure this one will work. http://plumbing.hardwarestore.com/52-30 ... googlebase Or do a search at Aubuchon hardware for ball valve. Dave
69S
Click to expand...

Sorry, I misunderstood your quote about the ball valve, I thought you where on about he Velo 350/500 type ball valve, which is slightly different as there is no tap to turn on and off :!:
 
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