Exhaust removal

Information relating to the Matchless G12 or AJS Model 31 650cc twin
GeoffR
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Joined: Wed May 24, 2017 1:37 pm
Location: GLOS UK

Exhaust removal

Post by GeoffR »

Hi, I need to remove the exhausts on my 1960 G12 and was wondering how they are fixed into the barrels. It appears that they are just pushed in? There is some evidence of a sealant of some description.

I'm used to bikes with studs and collets so I was hoping that someone can advise. Do I just unbolt the brackets and yank away until they pull out of the barrels? And when re-fitting them do I need to use a sealant?

Thanks in advance
Geoff
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Rob Harknett
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Re: Exhaust removal

Post by Rob Harknett »

Re move the silencer or silencers, depending what system has been fitted. Then pipe fittings until you are left with just the pipes in the barrels. The pipes were originally just pushed in, the brackets holding them in place. You say yours appear to have a sealant used, so you have to twist and pull to get them out. Perhaps over the years ports have worn due to pipes loose and chattering, cleaning and or repro pipes a bit smaller dia.
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ajscomboman
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Re: Exhaust removal

Post by ajscomboman »

I'm assuming you're pulling apart to make a start on fitting the centre stand. As Rob has mentioned it's just a push fit into the heads and when refitting I use plain low modulus builders clear silicone. Not so much to hold the pipe in but to seal any potential air leaks which will cause backfiring.
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Rob Harknett
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Re: Exhaust removal

Post by Rob Harknett »

A loose pipe will certainly make the engine back fire. I had a loose pipe on a G3/LS back in the 50's. Great fun, in particular at night. Overtake one of the other lads, pull in front and shut down. Very loud backfire and flame out the silencer about 3 foot long. Sometimes 2/3 back fires.
GeoffR
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Location: GLOS UK

Re: Exhaust removal

Post by GeoffR »

Yep, spot on....I want to fit the new main stand (hopefully it'll arrive in the post tomorrow or Saturday)

Thanks for the advice. I thought it must be pushed in, and I'll certainly use some sealant.

Cheers
Geoff
G15 Roy
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Re: Exhaust removal

Post by G15 Roy »

ajscomboman wrote:I'm assuming you're pulling apart to make a start on fitting the centre stand. As Rob has mentioned it's just a push fit into the heads and when refitting I use plain low modulus builders clear silicone. Not so much to hold the pipe in but to seal any potential air leaks which will cause backfiring.
Good job you mentioned the heads and not barrels. :o
Roy
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ajscomboman
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Re: Exhaust removal

Post by ajscomboman »

Hopefully it will I know the 2 I shipped to London arrived today as they were urgent and went TNT the others went Hermes on 3 day shipping so tomorrow should be the day.
G15 Roy
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Re: Exhaust removal

Post by G15 Roy »

ajscomboman wrote:Hopefully it will I know the 2 I shipped to London arrived today as they were urgent and went TNT the others went Hermes on 3 day shipping so tomorrow should be the day.
Fitting one more tomorrow on a twin just can't wait to have my fingers jamed up behind the gear box ;)
Roy
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ajscomboman
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Re: Exhaust removal

Post by ajscomboman »

G15 Roy wrote:
ajscomboman wrote:Hopefully it will I know the 2 I shipped to London arrived today as they were urgent and went TNT the others went Hermes on 3 day shipping so tomorrow should be the day.
Fitting one more tomorrow on a twin just can't wait to have my fingers jamed up behind the gear box ;)
Look the one I gave you the other day only took you an hour and you kept your fingers so this one will be even easier!! I've tested so many on the test mule twin I've got it down to 25 mins, no I'm not offering a fitting service before anyone asks!!!!!!!! :rofl: :rofl:
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clive
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Re: Exhaust removal

Post by clive »

Rob do you guarantee it will fit with the bodge up of spacers I currently have fitted? Incidently John didn't attend our section meeting last night so I didn't tell him about my stand being in the parcel. They nearly both went off with Jens for carriage to Poul. I will report back when I have removed fingers during fitting.
clive
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