Tanks

Information relating to the Matchless G12 or AJS Model 31 650cc twin
BruceB
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Tanks

Post by BruceB »

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?
66 BSA Spitfire MK11
77 Yamaha XS750 Triple
98 Suzuki Bandit GSF600S
78 Honda Superdream (rebuilding)
51 Cyclemaster (in queue)
56 G11 bitsa (in boxes awaiting courage)
78 Series Landrover (rebuilding)
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petert120r
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Location: POWYS UK

Re: Tanks

Post by petert120r »

Try Tank Care Products - google them for details
BruceB
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Location: INVERNESS-SHIRE UK

Re: Tanks

Post by BruceB »

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? :oops:
66 BSA Spitfire MK11
77 Yamaha XS750 Triple
98 Suzuki Bandit GSF600S
78 Honda Superdream (rebuilding)
51 Cyclemaster (in queue)
56 G11 bitsa (in boxes awaiting courage)
78 Series Landrover (rebuilding)
72 MG Midget (in queue)
06 Honda XL1000
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clanger9
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Location: Chester, UK

Re: Tanks

Post by clanger9 »

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 :shock:

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...
1989 Moto Morini Dart 350
1993 Ducati 750SS
Gibbo
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Joined: Sun Apr 24, 2016 8:51 pm
Location: NORTH YORKSHIRE UK

Re: Tanks

Post by Gibbo »

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. :headbang: 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 :D 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) :lol:
Sorry, can't help on the tank as I've still got that to do on mine.
Andy
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Duncan
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Re: Tanks

Post by Duncan »

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.
Andy51
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Location: BERKS UK

Re: Tanks

Post by Andy51 »

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
BruceB
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Re: Tanks

Post by BruceB »

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.
66 BSA Spitfire MK11
77 Yamaha XS750 Triple
98 Suzuki Bandit GSF600S
78 Honda Superdream (rebuilding)
51 Cyclemaster (in queue)
56 G11 bitsa (in boxes awaiting courage)
78 Series Landrover (rebuilding)
72 MG Midget (in queue)
06 Honda XL1000
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dave16mct
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Re: Tanks

Post by dave16mct »

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.
BruceB
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Re: Tanks

Post by BruceB »

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.
66 BSA Spitfire MK11
77 Yamaha XS750 Triple
98 Suzuki Bandit GSF600S
78 Honda Superdream (rebuilding)
51 Cyclemaster (in queue)
56 G11 bitsa (in boxes awaiting courage)
78 Series Landrover (rebuilding)
72 MG Midget (in queue)
06 Honda XL1000
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