Do I need a refresh?

[Matty]

Thanks all
If you have time to read the many pages under the heading Comet Smoking after
Rebore as specified above - ignoring the bits about reaming oil pumps and bike stands which have nothing to do with the topic - you will see that the oil hole is correctly drilled on my Comet, but in fact I blanked it off many years ago and it did not change the smokiness at all. It is OK to blank it with a disc in the timing cover on a Comet but not on a twin because the cam would be left unlubricated.

Most owners, including some of those who race do not use the cylinder feed holes and have no problems when using modern oils.

Other suggestions include- oil pooling round the inlet valve guide, worn valve guides, non-circular piston rings, oil pump not scavenging, blocked return pipe to the oil tank causing over lubrication to the rockers, mistimed or blocked breather, glazed bore caused by running in too slowly, porous head allowing oil into the inlet tract etc.
I have checked most of these possible causes of smoking exhaust with the exception of the porous head which if damaged could be fixed with impregnation of resin in a vacuum.
When I have done around 1000 miles or so in a couple of weeks to allow things to settle down I will see if the oil consumption is reasonable - say around 300 miles per pint, and if so carry on as I have been, using a bit of oil for the last 59 years!!!

Matty

 

[Alan J]

Colin weighs was much as a mosquito! That's why it goes so well! My friend Clive from J.B's " Real classic" articles is riding a beautifully restored 125 M.V,but he weighs 14 stone and crawls up the hills!

 

[vibrac]

That bit about worn carbs is even more appropriate to TT alloy jobs, a new TT transformed the racer and I am not talking about a new slide it always had that. The wear was just not easily identified on the old carb -but it was there.

 

[Colin]

Alan Why does your friend crawl up hills. If he's got a motorbike he should ride it up, if he 's not got the bike can't he just walk up. Otherwise you are right, just got over pneumonia and lost a stone in weight. How was your gallumping around Shri Lanka are you intending to go to France etc?

 

[Alan J]

I should proof read more often! Sri Lanka was great-had no problems, if a trifle hot! I have bought a modern m.g tf and hope to call in to the French rally,once again it is a long way on an outfit!! Sorry to hear you have been poorly, how can you loose a stone without disappearing?

 

[Matty]

Hi Kenny
I hope your Comet goes as well as it looks. It should be very reliable with all its parts in such excellent condition.
Mine is quite tidy and smart, and very original, but has a "patina" of use because it is ridden regularly - Summer and Winter.
I am very impressed with your efforts as a first time Vincent owner and hope you enjoy riding it as much as I do mine.
I feel that Vincents are like Marmite and you either love or hate them.

Matty

 

[Colin]

A & J Come with your camper, your penny farthing, your MG we don't care it's your company we want. You will see us there, you may miss me if I am turned sideways, but am working on it

 

[tim welsh]

A & J Come with your camper, your penny farthing, your MG we don't care it's your company we want. You will see us there, you may miss me if I am turned sideways, but am working on it

Steak you need Colin! See you and Alan in France I hope. As you say it matters not how you get there.
Tim

 

[Monkeypants]

- you will see that the oil hole is correctly drilled on my Comet, but in fact I blanked it off many years ago and it did not change the smokiness at all. It is OK to blank it with a disc in the timing cover on a Comet but not on a twin because the cam would be left unlubricated.



Matty

The cams on a twin get their lube via the spindles they sit on, , numbers 2&4. The cylinder holes are fed via spindles 1&3 so those can be blocked without reduction of lube to the cams. Terry Prince has plugged the cylinder holes on all rebuilds or new builds for years. The cams actually get a bit more oil this way as with the two cylinder holes plugged there is a tiny bit more oil available to the other locations, that is to say, the overall pressure in the system goes up a very slight amount.
On his top end kits the liners are shortened so that more oil is splashed on the cylinder walls.
The cylinder holes are plugged just by not drilling them through, however if this is done I think it makes sense to also plug the timing cover holes 1&3 as this should greatly reduce the possibility of oil oozing up around the cylinder bolt which is in contact with the pumped cylinder oil supply.

 

[KennyNUT]

Hi Kenny
I hope your Comet goes as well as it looks. It should be very reliable with all its parts in such excellent condition.
Mine is quite tidy and smart, and very original, but has a "patina" of use because it is ridden regularly - Summer and Winter.
I am very impressed with your efforts as a first time Vincent owner and hope you enjoy riding it as much as I do mine.
I feel that Vincents are like Marmite and you either love or hate them.

Matty

Many thanks for your kind words and empathy. I definitely love mine! I did hate it when I totted up the invoices in a spread sheet 3 weeks ago - but hey that was my decision to do what I did, after all, the bike was running, anyway, just puffing out some smoke, occasionally, along the way. To be fair a few members warned me of what would happen to my wallet! Anyway, I really love how the Comet has turned out. It looks fantastic and it taught me a number of things during this journey.

I have written some text and compiled some more photos of refurbed bits to finish this story of my Comet, though I have not posted this yet as I hope to take some final photographs of the bike and post those, too.

In the briefest summary, the wheels are rebuilt, the carb has been re-sleeved, the rear suspension all cleaned up an put back together, the tank (full story to follow) has been fully repainted, most other bits re-painted, new fuel taps added, new brakes, and everything put back together. The full story to follow.

I was feeling pretty bad at not having written anything for a while but work had been manic, I bought a new Italian Ducati bevel 1974 at the beginning of the year and as I had to import that (as very few of this model come up for sale in the UK), so there has been lots of supportive discussion with the DOC (GB) and the DVLA and today I took that on its first road run, mot's taxed and with a UK registration plate - amazing! As you can see lots of distraction, never mind kids and family stuff.

Anyway, back to the smoking Comet! - I promise to finish what I started and then run the bike in over the summer and hope to report back that it is not smoking! If it continues, then I will just live with it. Its a real beauty now and I am quite proud of having embarked on this journey. I have enjoyed it immensely.

Look out for the remainder of the write up within the week!