AJS & Matchless Owners Club

Finally got my recently acquired G12 650 partial rebuild finished and went a run where even more faults appeared. My petrol tank now leaks and my speedo cable snapped (I think). Useage seems to showing up the weak points on the bike and I seem to be simply going round the bike repairing more and more of the various parts and systems since I bought it although the basic condition seems to be OK.
Of these the tank is the most of a pain. I think someone had repaired it and lined it in the past and when I removed and replaced the tank I opened up the repair again.
Anyway I have two choices, clean and reline the tank again or send it away and get it repaired properly by rewelding on a stud where someone has bodged on something in the past.
The tank is in remarkably good condition,paint and steel, as far as I can see apart from the front nearside stud area.
It is from a 59 G12 so the studs are part of the tank and not seperate screw in studs as per the later versions. It looks like someone has welded a larger stud into the tank at some point and it is leaking somewhere around here.
The question is, does anybody know of a good reputable tank restorer and have a guide price of what it costs to have a tank restored and if necessary repainted, the online place are noticeable by the absence of any ballpark figures. This is understandable because it is hard to price it unseen but you would expect some guide?

Try Tank Care Products - google them for details

I'll give them a call and see what the options are.
Alternatively I don't supposed anybody knows of a tank for sale anywhere in good nick to save the bother?

Hi Bruce,

I think the going rate for a decent custom tank paint job is around the £200 mark - plus whatever the repairs cost. I had to get my fibreglass tank repaired & relined and it cost nearly as much again

Oh well, at least the fuel now stays where it's supposed to. The chances of me getting a replacement competition tank would be near zero, so I just had to grin & bear the cost...

Hi Bruce,
I am totally with you about the bit where every time you fix something and take it for a test ride another little "challenge" or two rears its head. I'm in a similar place, having fixed around 10 "little things", a broken speedo cable being one and that turned into a complete rebuild of a previously bodged rear hub. It still makes me smile every time I ride the bike (1960 31) though After all, she's 57 and as anyone that age will tell you, not all the "bits" work as well as the did when they were younger (newer)
Sorry, can't help on the tank as I've still got that to do on mine.
Andy

It is from a 59 G12 so the studs are part of the tank and not separate screw in studs as per the later versions.

Hi Bruce, your tank is probably more modified than you think, originally it would have used bolts (with a spacer tube and rubber and steel washers) to fix it not studs, studs will make the tank difficult to remove from the frame due to the handlebar/top yoke clearance.

Hi Bruce, I had my tank stripped (outside only blasted; inside with a handful of graavel and shaken) and petsealed 10 years ago. Lasy year the paint blistered in a rear corner, revealing pinholes. Admittedly the Petseal was the older, non-ethanol resistant type but it taught me a lesson - don't skimp on tank preparation, as I now have to have an expensive respray. Taking the advice of a metal cleaning specialist (R D Cox, Reading, Berks (very good), I had the bottom of the replacement tank cut out so the inside could be well and truly blast cleaned. The bottom was welded in again and I lined it with modern stuff. I won't know for another 10 years or more if this will work, but I know that the tank is fully clean inside and out, and properly lined. Cost about 100 quid, but considering the cost of a paint job, worth the money for peace of mind. Andy

As I understand it early bikes had studs instead of bolts. Certainly looking at mine, and it's an early 59 one with a single loop frame. However the tank removal issue is probably why it changed to bolts as it is difficult to get the tank off without scratching it on the handlebar mount.
I need to get the tank off and see what has been done where it leaks before deciding what to do about it.

Bruce that's wrong. They never used studs ever. They always had 5/16" Cycle thread bolts untill 1960 when a special bolt was used in a rubber bush. Your tank was a one off in that it was the same shape as the duplex frame models but was fitted the same as previous years ie 4 -5/16" bolts. Even the singles in 1959 didn't use this tank.

I cannot argue about it as I simply don't have a reliable parts book that is clear. However this information came From AMC classic spares when buying new rubbers. I was told that it was only 59 bikes that ever had this stud arrangement.
Certainly the tank, on three studs, doesn't look like it has been altered in any way but I need to get the tank off again and have a good root around.
The fourth stud is definitely bodged and is where the tank leaks.