Tin Chain Cases

bobbyb123 · Post by **bobbyb123** » Tue Jan 03, 2006 2:20 pm

Hi, I'm relatively new to the intricacies of fettling a Matchless and am in the process of making a "special", AKA, "I can't be bothered to wait for or even afford to purchase new tin wear, so I'll make it into a trial bike" Could someone please advise whether its possible to fit a later tin outer primary chain case with a removeable clutch adjusting dome to an inner case that was matched to an original none removeable dome, or are they paired for some engineering reason and I have to fit them as a pair? I intend to fit stainless oil hoses instead of the original rigid ones, is this, not withstanding cost or originality, a good or bad decision?
Thanks, Bob

Biscuit · Post by **Biscuit** » Tue Jan 03, 2006 4:55 pm

I believe you can mix and match any year of PRESSED STEEL chaincase, except of course single and twin inners. As long as the pipes/hoses carry the oil and don't leak, go for it.

Biscuit · Post by **Biscuit** » Tue Jan 03, 2006 4:56 pm

Whoops - finger trouble!!!!!!!!!!!Edited by - Biscuit on 03 Jan 2006 4:58:39 PM

Dick Hobart · Post by **Dick Hobart** » Tue Jan 03, 2006 6:50 pm

Hi Robert
I'm sure what Alan says is correct, and going for an outer with the removable dome is a good move, but don't forget that you'll be moving into the time (57 road bikes; 57 - end comp. bikes), when the shock absorber moved from the engine to the clutch with a corresponding smaller front dome. Make sure you get one with a front dome to suit your needs, unless you're able to modify accordingly. No problem with the hoses - lots of trials and moto-cross lads have done what you propose.
Good luck - Dick H

Chazzyb · Post by **Chazzyb** » Wed Jan 04, 2006 3:01 pm

quote:
Hi Robert
I'm sure what Alan says is correct, and going for an outer with the removable dome is a good move, but don't forget that you'll be moving into the time (57 road bikes; 57 - end comp. bikes), when the shock absorber moved from the engine to the clutch with a corresponding smaller front dome. Make sure you get one with a front dome to suit your needs, unless you're able to modify accordingly. No problem with the hoses - lots of trials and moto-cross lads have done what you propose.
Good luck - Dick H

I may well be wrong, but I thought AMC boxes (with s/absorber) were matched with alloy chaincases, not pressed steel. The upshot being all steel chaincase outers are designed for drive shaft s/absorber.

Biscuit · Post by **Biscuit** » Wed Jan 04, 2006 3:09 pm

Charles, with my basket case G3 it came with pressed steel case with a very short sprocket/drive shaft housing, so they are about.

Chazzyb · Post by **Chazzyb** » Wed Jan 04, 2006 7:19 pm

quote:
Charles, with my basket case G3 it came with pressed steel case with a very short sprocket/drive shaft housing, so they are about.

For '57 perhaps? Roy Bacon says AMC boxes fitted in '57 but alloy chaincases were introduced for '58.

Biscuit · Post by **Biscuit** » Wed Jan 04, 2006 8:43 pm

Dunno where it came from, I cut the short bit off and stuck on the long type from a very rusty case (rusty as with holes!!)

Don Madden · Post by **Don Madden** » Thu Jan 05, 2006 9:37 pm

Chazzyb is correct as to Roy Bacon's book but the tin cases were used much later on some competition bikes. Through 1959 for scramblers & to the end for trials.
Cheers, Don

Dick Hobart · Post by **Dick Hobart** » Thu Jan 05, 2006 10:14 pm

With respect, Don, isn't that what I said? I wouldn't have posted it if I didn't know it to be correct. And your right about the scramblers - for reasons best known to AMC some scramblers post '59 appeared with the alloy cases, some even with the alternator housing although there wasn't an alternator there! Most lads threw them away and fitted the tin sets or home made sheet alloy ones. They weren't too worried about oiltightness as even the Seniors' final was only a six lap dash in those days. Far more important to be able to quickly change the gearing by changing the engine sprocket to suit the circuit or changing conditions without having to fiddle with umpteen little screws!