1954 Comet C - broken cam follower

  • Thread starter charlottevictoria
  • Start date
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Graham Smith

Guest
I wonted to upload two fotos of the broken Part and got that message:
Error creating thumbnail! Error code: 1

Command:

"/usr/bin/mogrify" +profile "*" -size 0x100 -quality 70 -geometry 0x100 '/var/www/html/photos/data/500/thumbs/IMG_10581.jpg'


Do you have any idea how to add a Photo to that forum?

Leave it with me. I'll try to have a look to see what's wrong this evening, but I'm still trying to get MPH to the printers, so may struggle. Please bear with me.

Graham
 

Hugo Myatt

Well Known and Active Forum User
VOC Member
Dear all,

I have found a piece of metal which may come from the exhaust cam follower. So I want to remove the steady plate and the cam sprocket to see where is the problem. Now I have some questions:
1) Should I use new nuts for the steady plate or may I use the old ones at the end?
2) Are there any problems removing the cam pinion?
3) how does the cam fit togeather with the cam pinion?
4) does anybody have a photo, which shows how it looks behind the cam idler?
5) do I have to remove the large idler too?
6) is it possible (and helpful) to fit a black lightning camshaft?
I drive the bike with a blacknell bullet sidecar an 60 teeth on the rear sprocket. It runs 65mph. A few horspowers more shold help climbing hills.

Thanks a lot for your help. Please answer to my e-mail-address kohl.lalo@web.de

Yours
Peter Kohl

Peter,
I once found a stray piece of metal at the bottom of the timing chest. After much head scratching I realised it was one of the projections from the rocker bearing collar as used with locking rocker feed bolts. Presumeably it had broken off through over-tightening. Somehow it had dropped down the pushrod tube to the bottom of the timing chest without causing any further damage.
 
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charlottevictoria

Guest
According to the Rider's Handbook a Comet with 60 tooth rear sprocket does 763 rpm for every 10 mph. Therefore at 60 mph the revs should be about 4578 rpm, at 70 mph about 5341 rpm and at 80 mph about 6104 rpm. These figures are all well within the capabilities of a Vincent. So it is lack of power which is the problem,not an inability to rev higher. Try the outfit down a steep hill and if it will not exceed 65 mph then something is stopping it breathing properly or something in the transmission is not free. I was lent a Comet to ride solo a few years ago and it really was gutless. It did about 70 mph with me looking like a young tearaway down on the tank. The owner thinks that it is fine but I rode a Comet as a 'go to work bike' over 40 years ago and it was much better than that. Even the lack of 5 star fuel should not be causing that much of a deterioration.
many years ago, when I drove without sidecar the comet went more than 85mph.
 

deejay499

Well Known and Active Forum User
VOC Member
Charlottevictoria.
Everything that Phil Primmer says about your Comet outfit is right. 65mph with a Blacknell Bullet is pretty good, as the chair is pretty heavy. Good luck with the timing chest. Hope it is not too serious.
DJ
 
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charlottevictoria

Guest
IMG_1062.jpgIMG_1063.jpg
here is the damaged unit
 

Bill Thomas

Well Known and Active Forum User
VOC Member
Hello Peter, It has happened many times, It is a weak part, The advert Timetraveller told you about do a Stronger unit, Good Luck, Bill.
 

Alan J

Well Known and Active Forum User
VOC Member
Peter, with a magneto, it is best to fit "a cutout"- i.e. a method of "earthing" the volts to the frame, in an emergency-like a stuck throttle cable. 70 m.p.h. with a comet is good going!!
 
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