1955 G9 recomissioning

Information relating to the Matchless G9 or AJS Model 20 500cc twin
Oggers
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Location: Aberdeenshire

1955 G9 recomissioning

Post by Oggers »

Chaps

I have just taken delivery of a very smart 1955 G9 which has undergone a full restoration. However, I think it has been standing for some years, and thus needs a little checking over before riding and running in. The bike started when first viewed, no smoke at all, and it sounded very sweet.

Any helpful tips as to what to look for - particularly as regards the G9 - before I take it for a spin would be much appreciated.

Generic things I thought of

Replace petrol
Check tyres
Check brakes
Check plugs
Oil pump return fine...change oil after 200 miles or so?
Clean out carb - Monobloc.

Anything else...


Thanks and regards....
Mick D
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Location: Aberdeenshire

Re: 1955 G9 recomissioning

Post by Mick D »

Hi Oggers and Welcome

If it ran without issue when you viewed it all I'd do would be to check the brakes, lights, levels and tyres, give the bike a general 'look over' for leaks and take it for a series of runs. Start at a few hundred yards and work up with an inspection as per above after each run.

I see you're in Aberdeenshire - anywhere near Turriff?

Regards Mick
Oggers
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Re: 1955 G9 recomissioning

Post by Oggers »

Mick - about 6 miles NW of Banchory, so in Aberdeenshire terms, near-ish!

Just picked it up today....
MalcW
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Re: 1955 G9 recomissioning

Post by MalcW »

Hi

Based on my experience of recommissioning my twin, I would suggest that when you change the petrol you have a look in the tank with the aid of a torch and mirror, just to see what state it's in. If it starts and runs OK, I wouldn't bother stripping and cleaning the carb at this stage - save that for if problems show up on the road. I would also change the oil immediately, not after 200 miles or so. When you check the tyres, see how old they are. There should be a DOT code on there somewhere, and at the end of it will be a number like 2514, 25/14 or similar. This means the tyre was made in week 25 of 2014. If it isn't there, the tyre was made before 2000. The general consensus seems to be that tyres over 10 years old should be replaced, even if they look OK.
Other than that, Mick has covered everything. Again from experience I agree that you should build up from a few hundred yards, checking everything after each ride. Take a few basic tools with you, so you can make basic adjustments by the roadside, if necessary.

Malc
SPRIDDLER
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Re: 1955 G9 recomissioning

Post by SPRIDDLER »

Oggers wrote:I have just taken delivery of a very smart 1955 G9 which has undergone a full restoration.
Welcome to the club and Forums, Mark. From the experience of chums who have them the 500 twin seems to be the least troublesome and most owner and rider friendly of all the twins.
I see you have other old bikes and far be it for me to drip monograde on your drive but unless you have firm evidence of the extent of the restoration take nothing for granted. ;)
Agree with all above plus it's a good habit to check that oil is returning to the tank at every first start-up of the day.
Enjoy!
'There is a tide in the affairs of men
Which taken at the flood............'
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1608
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Re: 1955 G9 recomissioning

Post by 1608 »

As all the above and especially as Nev has added, take now't for granted. How thorough was the rebuild! I would be inclined to check the sludge trap. I know it means a rebuild, but if it was done properly then there will be the minimum of parts expense and great peace of mind.
SPRIDDLER
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Re: 1955 G9 recomissioning

Post by SPRIDDLER »

1608 wrote: How thorough was the rebuild! I would be inclined to check the sludge trap. I know it means a rebuild, but if it was done properly then there will be the minimum of parts expense and great peace of mind.
Yes, I agree John, in an ideal world that would be a sensible move but I guess Mark is keen (excited even) to get riding it rather than start stripping the engine.
I would suggest first contacting the 'restorer' for specific info on what he had done, if anything, to the engine. The 'full restoration' may have just been cosmetics and an oil change............
'There is a tide in the affairs of men
Which taken at the flood............'
Mick D
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Re: 1955 G9 recomissioning

Post by Mick D »

Hi Mark

Were you at Crathes last year with a Bonnie? if so I think we have met.

Regards Mick
Oggers
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Re: 1955 G9 recomissioning

Post by Oggers »

Mick - No, but doubtless you met the PO of the Bonnie - Chris ???. I was there though - with my highly modified MG Midget. Crathes is excellent is it not? Looking forward to another splendid day with another record entries!

Spriddler et al - Quite right. There is no possible justification to start an engine strip! I have no doubts about the resto - even though it is just word of mouth. The overall condition of the bike tells me that much, though clearly I will not be able to confirm 100% until I start to ride it.
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clive
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Re: 1955 G9 recomissioning

Post by clive »

SPRIDDLER wrote:
1608 wrote:
I would suggest first contacting the 'restorer' for specific info on what he had done, if anything, to the engine. The 'full restoration' may have just been cosmetics and an oil change............
Now now Sprids we are not all as generous with our stretching of the truth. I mean an oil change is that really necessary during a restoration?
clive
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