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Dave

2024-06-11, 20:02:05
Have you tried the new Drafts feature yet? I just lost a long message today and learned my lesson. It is a good idea to save a draft of any long post you are writing. You can then just keep writing and keep saving a draft, knowing you have a backup if there is a glitch. The draft is automatically deleted when you post the message.

Dave

2024-06-08, 18:30:04
For Sale
xman has two very nice 1950's machines available - a green 1950 mk4 and black 1951 mk5 - both in good condition and running well.

Dave

2024-06-07, 02:13:36

Dave

2024-06-03, 08:23:05
For Sale
Duncan has just listed his green and cream 1957 Dragonfly for sale with spares and documents.

Dave

2024-06-02, 08:34:05
Parts avalable
alistair still has parts available - barrels, carburettor, castings - see all listings.


Dave

2024-06-01, 18:33:27

Dave

2024-05-28, 00:09:46
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Advice on larger bore/pistons

Started by sidecar willy, 19 Dec 2007 at 19:49

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sidecar willy

Hi...I am sure Doug will be able to help here.

I recently picked up a spare 250 cc Comet engine which looks as if its been well used with the inside of the timing cover and crankcase gummed up with thick black oil [indicating either high mileage or that the oil never got changed]The engine came complete with a magneto and pancake dynamo. Good spares.

I intend to have the engine overhauled with new bearings and pistons...but as I will have a rebore on the cylinders..just wondering how far I can go with larger pistons. There looks like a lot of meat on the bores...and assuming I can get larger pistons thought I could take the bore out as far as I can take it. Of course this puts a strain on the bottom end...but with new bearings this might be possible.

Any ideas from the forum would be handy!!!

cheers
Bill

Edin

#1
Quote from: sidecar willy on 19 Dec 2007 at 19:49

Any ideas from the forum would be handy!!!   cheers  Bill

Hej Bill
3 or 4 years ago I made 250 Comet from the bottom.  As right I remember, I found out at that time, the 250 and 350
cylinders are identical - with exception of cylinderdiameter. I have stil many parts from that project.
kind regards Edin DK


Edit:  Quote tags adjusted 20/12/2007.  A.