Rear sprocket

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
Trebor160
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Posts: 29
Joined: Fri Nov 03, 2017 9:36 pm
Location: Oldham UK

Rear sprocket

Post by Trebor160 »

Hi All - just rebuilding the G5 and the rear wheel sprocket is looking a bit worse for wear. Any ideas were I can locate a replacement. It has 55 teeth and the part number is: 043230. Ive tried all the usual places, including our own Jampot spares listings, but no joy unfortunately....
Thanks, Rob
bitza
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Posts: 452
Joined: Tue May 27, 2003 1:00 am
Location: SHROPSHIRE UK

Re: Rear sprocket

Post by bitza »

If it's not a combined brake and sprocket you could try, WWW. THE - CHAIN - MAN.CO.UK PHONE. 01299 403688 names ANDY,
They do plain bore sprockets, and can machine to pattern,
Also.
JOHN HEMMING ENGINEERING, UNIT M TIMBER YARD, BUCKNELL, SHROPSHIRE, SY7 OEL. Phone 01547 530759
They retooth drum sprockets

Www. Sprockets unlimited.com
Phone01386 831341
Greybeard
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Posts: 456
Joined: Mon Jun 29, 2015 8:49 pm
Location: East Yorkshire

Re: Rear sprocket

Post by Greybeard »

I can recommend John Hemming's work, but he's not quick. He did the engine sprocket for my 1937 Sunbeam Lion pretty quickly. The rear drum/sprocket took months and I never got to ride it at all that season. A nice job when it did turn up after several failed promises of delivery.

Steve
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Ozmadman
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Joined: Wed Dec 14, 2011 1:02 am
Location: ESSEX UK

Re: Rear sprocket

Post by Ozmadman »

It is just a plain bolt on sprocket, pity as the club had some about a year ago which had one hole drilled incorrectly and they sold them off for £5 each!!! presume from your comments that they never had any replacements made. Maybe Gary can let you know where they got them from
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
Trebor160
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Posts: 29
Joined: Fri Nov 03, 2017 9:36 pm
Location: Oldham UK

Re: Rear sprocket

Post by Trebor160 »

Thanks guys - yes its just a plain sprocket plate with six fixing holes in it. I'll carry on trawling the internet and using the suggestions below.
I know they didn't make many G5's but I believe they're very similar to the G2's (250cc version) and the AJS MK 8 which they sold a lot more of. I would have thought spares that were common to all versions would have been more readily available..........

I'll give below a call in the new year and see if they can do a replacement or knock one up, otherwise its back on with the old one.
Cheers, Rob
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Ozmadman
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Joined: Wed Dec 14, 2011 1:02 am
Location: ESSEX UK

Re: Rear sprocket

Post by Ozmadman »

trebor161 wrote:Thanks guys - yes its just a plain sprocket plate with six fixing holes in it. I'll carry on trawling the internet and using the suggestions below.
I know they didn't make many G5's but I believe they're very similar to the G2's (250cc version) and the AJS MK 8 which they sold a lot more of. I would have thought spares that were common to all versions would have been more readily available..........

I'll give below a call in the new year and see if they can do a replacement or knock one up, otherwise its back on with the old one.
Cheers, Rob
G2's will fit but might be one tooth difference (possibly later ones might be 54 teeth as early ones appear to be the same) and the AJS model 8 is the same as it is the same bike apart from livery. Try to stick to the same amount of teeth or less as the G5/Model 8 is way under geared in my opinion and you will wonder why you need 1st gear at all. Many on here use a 19 or even 20 tooth gearbox sprocket (with a 55 rear sprocket) instead of the standard 18 tooth especially if using the bike for runs as it keep the revs down at cruising speed. If you just knock around town or live somewhere where you have to go up steep hills all the time then leave it standard otherwise it will seem to be revving too much at say 60 mph.
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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Janet
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Joined: Mon Jan 01, 1996 12:00 am
Location: EAST YORKSHIRE UK

Re: Rear sprocket

Post by Janet »

Rangy 65 and I are looking at getting some sprockets manufactured for the lightweights. They will probably be 55 toothed as this seems to suit most of the models.

I find having a 1st gear on my lightweight is very useful. I'm also used to high revving engines.
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Rangy65
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Location: LINCOLNSHIRE UK

Re: Rear sprocket

Post by Rangy65 »

HI all as Janet has said we are looking to find a supplier/manufacturer who will not only supply the blank sprockets but machine & drill them too. I have just fitted one of the mis-drilled sprockets to the lightweight i am currently building so i have a worn 55 tooth sprocket as a pattern. Will start calling round the list of companies that i have this week and try to get a feeling for minimum order and prices.

Keep you posted.

Steve
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Janet
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Location: EAST YORKSHIRE UK

Re: Rear sprocket

Post by Janet »

A question for lightweight owners. If we were able to source rear sprockets ( ie the one on the back wheel ) without having to modify them to fit lightweight machines, how much would you be prepared to pay for one?

Note: this would be on behalf on Jampot Spares and not advertising a private enterprise.
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dodger
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Joined: Sat Jan 01, 2000 12:00 am
Location: HAMPSHIRE UK

Re: Rear sprocket

Post by dodger »

I have one on order from John Hemmings Engineering at £60.00 so if Jampot spares can negotiate a deal for say 50 or so then economies of scale should mean they come in under that cost.
Since ordering the above I now need another two so will hold off ordering from Hemmings until you come to a conclusion one way or another.

Laurie
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