Do I need a refresh?

[KennyNUT]

Wow, if that's the best thing you did in 25 years......especially in that beautiful city of "opportunity" that you live in.

Only, joking, however, I guess you do spend a significant time snowed in, especially at this time of year. Keep warm and dream of those ride outs in 2015.

In truth, I am really happy that I can potentially, have the refurbishment done and so still use the original carburettor with that likely to last 25 or more years with more accurate metering of the fuel/air mixture at low revs and idling. This work that has turned into something more significant than a refresh, however, it has been really great. I am a bit smitten by the engineering prowess of those who can actually do what I have to outsource. However, so be it!

One last thing, Bob, just be sure that if you are married that "your dear wife" did not see your last reply. That's assuming you were married within the last 25 years. Otherwise, you may just live to tell the tale.

Have fun in 2015.

 

[Bazlerker]

lol..indeed...I am married, and for less than 10 years. Spring will soon be here - only another 4 1/2 months of winter!

 

[Matty]

Hi This is Matty

There is a long set of comments which may be of interest to other "smokers" regarding my Comet at :-
Comet Smoking After Rebore Is the Bore Glazed ?
Discussion in 'Technical Advice: Public Access' started by Matty, Jan 28, 2015

I have had my Comet for 59 years and it has always smoked a bit and sometimes sumped.
I do a fair amount of miles on it all year round including a 1000 mile + round trip to the Isle of Man each year since around 1975.
I am pretty pragmatic about how it looks and it is virtually as it came out of the factory, with a magneto, awful standard brakes, 6v lights, alloy guards etc.
I have rebuilt the engine twice in the 90,000 miles it has done, and it still only does about 250miles to the pint of oil.
It is very reliable, pretty tidy cosmetically and has never let me down on the trips to the IOM. All I do is make sure all the bits work properly (with an electronic voltage regulator and Miller dynamo rebuilt to look like a Lucas one).
I do have some engineering skills however and am qualified as an electrical/electronic engineer after an apprenticeship in which I was taught to use lathes, mills, etc and do some sheet-metal work and instrument making. So maintaining the bike is not a problem technically but old age is now making the physical work pretty back aching !!

Happy Smoking

Matty

 

[Gene Nehring]

Kenny,

I bought my Comet under the same sort of conditions, in fact your experience is almost exactly the same as mine.

When I bought my Comet it smoked a bit and had been rebuilt ten years earlier. It too was good up to 70mph and was generally pleasant to ride. I was riding with my friend Mike after John M rebuilt his Comet motor and I knew something was not right buy just listening to the difference between the two machines. Riding beside Mike made it more obvious to me that something was off.

So this winter I pulled the head and found that the piston had an extremely worn thrust face and that other sundry items needed attention (including big end). I know have John rebuilding my motor and I can't wait to have it back in the bike.

We have new parts from Maughan and sons, valve springs from Terry Prince and some other upgrades. This is worth it to me to be able to have trouble free motoring for years to come.

In short find someone to have a good look at it for you if you are not comfortable or don't have the experience. Top end would be the best out come, complete rebuild even for a comet is not cheap.

Eugene.

 

[Matty]

Thanks for your reply. As I said I bought my Comet in 1956 - and have the engineering skills to rebuild the engine as necessary. In fact as a hobby I have rebuilt many bikes including a Vincent twin, a Scott, Douglas 90+, and around 60 written off modern bikes - BMWs, Fireblades, CBR 600s, Kawasaki Ninjas etc.
The insides of my engine have been fully replaced over the years an are in excellent condition but I am just trying for academic reasons to find out why some oil is still used.

Thanks again

Matty

 

[Martyn Goodwin]

Thanks for your reply. As I said I bought my Comet in 1956 - and have the engineering skills to rebuild the engine as necessary. In fact as a hobby I have rebuilt many bikes including a Vincent twin, a Scott, Douglas 90+, and around 60 written off modern bikes - BMWs, Fireblades, CBR 600s, Kawasaki Ninjas etc.
The insides of my engine have been fully replaced over the years an are in excellent condition but I am just trying for academic reasons to find out why some oil is still used.

Thanks again

Matty

Just musing over the matter. For the oil to "be used" it must go somewhere. It could be leaking from the motor or it is getting past the piston rings and being burnt or it is getting down the valve stems - inlet valve would see it burnt inside the combustion space and exhaust valve would see it gong out of the exhaust. Cannot think of any other alternative.

 

[Jim Richardson]

My fully rebuilt "0 miles when I got it" Comet, used to do a verified 85 mph, until I added around 28lb to the area above the seat, I am currently trying to reduce this added weight, without recourse to drilling holes!

 

[Robert Watson]

One thing worth checking, as we just discovered on a twin that smoked. The oil feed holes to the thrust face of the pistons were incorrect. They entered the cylinder at a point above the oil ring, in fact about even with the middle ring when the pistons were at BDC. Been like that for years.

 

[Colin]

My (Egli) Comet which I have now owned for about 35 years, would (about 35 years ago) happily do about 85 plus MPH, and went better the more it was thrashed (despite some noisy rattley bits- which are easily sorted out simply by getting better ear plugs!) As time passed it didn't seem to go quite so well, so I would fiddle with the carb, fitted bigger main jet etc etc. About 2years ago I found it really was beginning to struggle to get to 70, and maintain that speed. So I did a bit more fiddling-not much better. Then, whilst looking roun at Stafford Show I had a word with Messrs Amal, and to cut a long story short I ordered a brand new Mk One Concentric to exactly the same spec as the original bike builder had put on the bike, some 40years earlier! I did remark to myself at the time that the original spec.main jet was 170 and I had now got up to about 210, POW The bike is transformed, I can wang it up to 70 plus in 3rd bang into top and the old 85mph is back. I would add the bike has Mk one -and -a -half cams (a Ron Kemp speciality some years ago) and when my original Burgess straight through silencer finally had to be cut off it was replaced by an Armours straight through job (which is very well made and not restrictive) I use a 49 tooth rear sprocket (fitted by original builder) and the engine is as noisy rattley as ever, runs on 20/50 oil (though years ago I always used mono 40 sae in summer, or even mono 50 sae when touring in hot countries, and mono 30 sae in winter)Also years ago when hot and on the over run it would smoke like The Royal Scot, running uphill .So what,a quick plug chop would see us off again. Mac Reid solved it for me in the end by fitting oil seals on the valves. The little Egli engine is very noisy (it is entitled to be as it is a 1950 job which spent some of its life as Pete Gerrish's sidecar TT power plant!) but it does GO! So the moral of this taleis twofold 1) If you are worried by clatter/rattle etc, get better ear plugs and 2) If it ain't broke don't mend it!

 

[Colin]

I should also have said that carb. wear is insidious, inevitable, ongoing and easy to overlook, especially without an air filter