G2CSR barrel

Biscuit · Post by **Biscuit** » Wed Nov 29, 2006 11:29 pm

So it appears that both schools of thought are correct.

Why use terms like 'negative' and 'contradictory'? completely unnecessary.

chris kelly · Post by **chris kelly** » Wed Nov 29, 2006 11:31 pm

Hi ,again.

As your bike is a 1965 bike , then it is silver.

Chris.

good-hifi · Post by **good-hifi** » Thu Nov 30, 2006 9:32 am

quote:
So it appears that both schools of thought are correct.

No, Chris revised his conclusion.

The bike is a 1965 bike and the question was what colour should the barrel be. The correct answer is silver.Edited by - good-hifi on 30 Nov 2006 09:59:18 AM

basketcase · Post by **basketcase** » Fri Dec 01, 2006 3:06 am

Thanks all, totally confused now!! Pink it shall be, with black AND silver spots. Cheers, basketcase.

good-hifi · Post by **good-hifi** » Fri Dec 01, 2006 8:14 am

Too may answers spoil the broth. Only one answer was required....

Anywyas, whatever you want, it's your bike. Mine is not standard. Apart from the silver barrel that is.

As a more serious aside the silver barrel is also better for cooling (the same reason radiators are white, black abosrbs heat) and I suspect that this is the reason AMC finished it silver since the CSR has a higher compression pistons than the standard bike it will rrun hotter......

Cheers

itma · Post by **itma** » Fri Dec 01, 2006 11:09 am

makes no bloody diference at all, its a styling exercise, done to dupe the gullible into believing its an alloy "sports" cylinder.
same logic as putting AJS on a chinese whatever.

I love my Matchless machines but find all this back- inference implying higher thinking on the finer points of finish a bit niave
1965 = AMC going down the pan, anything to shift the stock was the case.

matman · Post by **matman** » Fri Dec 01, 2006 2:05 pm

quote: As a more serious aside the silver barrel is also better for cooling (the same reason radiators are white, black abosrbs heat) and I suspect that this is the reason AMC finished it silver

Sorry, Mick, in this point I have to contradict you. The black colour absorbed the heat from inside the barrel and led it on the outside, to the cooling fins, where it could better be dissipated by the airstream. So, black coloured components were/are especially found where high temperatures had/have to be handled.
Just remember the nice, matt-black bonnets of 70's rally and race cars? They were intended not only to take away the heat from the engine compartment but to avoid unwanted sunlight reflections from glossy varnished surfaces, too.

And when I look under the bonnet of my '67 Volvo Amazon or my '71 Mercedes 250C, the radiators seem rather black than white to me... So the white radiators in your living room should not lead you to wrong conclusions - they are white to avoid burning your b*tt

good-hifi · Post by **good-hifi** » Fri Dec 01, 2006 10:24 pm

Matt black is one of the most absorbing colours of all. It absorbs heat as well as light. Bonnets were painted matt black to cut down on light reflections. Matt black bonnets got hot from the sun and were the worst thing you could have to help cool an engine bay. Read up in some of the old rally books about heat transfer problems.

So matt black was not used to help cool engines. It used to be fashionable to have crackle black exhaust manifolds but that was nothing to do with cooling. Radiators are black because what is the point of having a light colour on a component that is the first to get dirty on any car and is impossible to clean.

Heat travels from the internals of the cylinder to the outside by conduction, black paint on a barrel has no effect upon that in any way shape or form.

Black does not conduct heat, it absorbs it and the mere fact it absorbs it means that, by definition, it is not good at releasing it.

Heat is transferred from the barrel by convection. Black is poor at transferring heat and white is good at transferring heat. Convection relies upon free release, hence the use of silver to help cool the barrel.

Don Madden · Post by **Don Madden** » Sun Dec 03, 2006 2:45 am

Hmmm. Somebody needs to go back & read his primary school physics text book that is propping the door open.
Cheers, Don.

chris kelly · Post by **chris kelly** » Sun Dec 03, 2006 10:10 am

http://answers.yahoo.com/question/index ... 436AAeNlhX

Hi all,

'school physics text book that is propping the door open'

In the Beano/Dandy they had the text books on top of the door...!

Actually, Mick's contribution above, read carefully, is I believe correct.

For a clear, easy to understand , short explanation of the properties of light, colour reflection, heat tranfer etc then refer to above Link.
Best wishes, Chris.