Fear not for I have returned, and 350cc Pistons

Information relating to the Matchless G3 or AJS Model 16 350cc Heavyweight
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jackstringer
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Fear not for I have returned, and 350cc Pistons

Post by jackstringer »

First things first, I'm Back. Sorry.

My Matchless broke a few years back after I took it to Wales for a weekend away, the piston crown came off and decided to disintegrate into many small bits. So the bike ended up in bits and because I also own a Land Rover I spent a fair bit of my time trying to keep that running I didn't do much with the Matchless. My dad took it apart and parts have been spread all over the bench.

But I am now putting it back together using a GPM piston that I had bought to put an AJS back on the road so I now need another piston. I have tried to contact the Italians to see if they still sell the pistons but no response. Thankfully I have managed to source some new rings as one of the rings went ping as we fitted it to the Matchless.

So back to my reason for posting,
Has anyone done a write up similar to Don's work on the 75mm Bores on twins (http://www.jampot.com/article_read.asp?id=23) but for the 350cc Singles?
also
Where is the recommended place for new pistons for the 350cc bikes?
bitza
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Re: Fear not for I have returned, and 350cc Pistons

Post by bitza »

Try the club spares or failing that, give A M C Classic spares a call .
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jackstringer
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Re: Fear not for I have returned, and 350cc Pistons

Post by jackstringer »

The Club site isn't showing any available but I will try that AMC place you suggested.

I did make contact with a firm I know from my work and they reckon they can do Pistons for £130 ish based on me ordering 12. I must point out this firm is based and I know some of their pistons go into some very nice things so would be top spec. So any other G3 owners interested, I must say I do need to look up the different pistons but I suspect I would try for the best compression ratio etc.

If you want to see the state of the piston I broke them here it is, https://blog.jackstringer.co.uk/my-vehi ... s-g3ls-61/
SPRIDDLER
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Re: Fear not for I have returned, and 350cc Pistons

Post by SPRIDDLER »

jackstringer wrote:The Club site isn't showing any available
Have you asked when they may be available?
Are you looking for a standard piston or one of the three oversizes?
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Which taken at the flood............'
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jackstringer
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Re: Fear not for I have returned, and 350cc Pistons

Post by jackstringer »

SPRIDDLER wrote:
jackstringer wrote:The Club site isn't showing any available
Have you asked when they may be available?
Are you looking for a standard piston or one of the three oversizes?
As they are likely to be on Holibobs I won't get a reply to the new year but I will ask. I will be looking for an oversize, and prefer a +.20 but can go further out if needed.

I only asked the UK firm I know as I was just curious as to the rough price of a high standard piston considering the usual reply I have had in the past (from members) is to buy pistons that people can't find anymore or covert to a piston that they had a few of in the shed but again not easy to find. I was quite surprised that I got a reply from this firm today after less than 8hrs of sending an email.

I was quite surprised at the recent VMCC autojumble in Somerset that there was a good amount of AMC stuff there so I ended up with another barrel and some STD pistons.
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Re: Fear not for I have returned, and 350cc Pistons

Post by SPRIDDLER »

jackstringer wrote: I ended up with another barrel and some STD pistons.
Rotten luck if none of those pistons match your current or the jumble barrel. Maybe have one of the barrels re-linered back to standard, then you'll have plenty of pistons. :?
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jackstringer
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Re: Fear not for I have returned, and 350cc Pistons

Post by jackstringer »

I paid £5 for one without rings and £15 for one with, there were of more use as testers for barrels we see, but now I have a very near (must take it with me) and I have made notes on the bore sizes. Both Hep Pistons but of slightly different designs. The barrel is sadly in need of a rebore after we honed the surface rust off as we can see a bit of pitting. The way I look at it, it was cheaper than the last Autojumble as I ended up buying another project bike.

I am tempted to get the barrels I have that are a little foxed and on the sloppy side re-sleeved.
bitza
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Re: Fear not for I have returned, and 350cc Pistons

Post by bitza »

You could also try F W Thornton Ltd , based in Telford Shropshire, they carry a large range of rings, bearings etc , got my G9 rings off
The shelf.
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Peter Morris
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Re: Fear not for I have returned, and 350cc Pistons

Post by Peter Morris »

Can't beat Cox & Turner for rings

https://www.coxandturner.co.uk/piston-rings
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Re: Fear not for I have returned, and 350cc Pistons

Post by Pharisee »

I had my 350 G3 re-sleeved by T & L Engineering. They also supplied the piston so it may be worth giving them a call 01234 352418.
John
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