Fuel tank mounts.

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The LR/Interpol tank was low volume and hand made and the base made up from numerous parts, the Roadster and Interstate tanks were high volume in comparison so the base was a single pressing.
 
Does that mean the Roadster tank is Norton made and not a EMGO ? (I am hoping so)
 
That is good enough for me, it left the USA before the EMGO was introduced if 2014 is the first production.
The tank will have to wait, I will if brave try and draw it in or machine two adaptors that will use the existing stud locations but move the bobbins inward to something closer to the correct 5-3/8".

If it is some 7/8's wider, trying to draw it in that much might end in tears, a thread to be updated in the future.
Thanks for all the replies. :)
 
If you try and pull the tank back into shape using the studs you will rip at least one of them out of the tank and leave a big hole. I have an Interstate tank that had very little force applied to one of the studs and the metal piece that the stud screws into ripped out and left a hole about an inch across. The tank metal is pretty thin. Big job to repair.
 
Thanks Nortoniggy.

I will repair the right hand frame mount hole and machine some adaptors to move the bobbins in.
For its age it is to nice to risk damaging (more than it is already damaged)

Fuel tank mounts.
 
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FWIW, and I don't how much detail you can pick out, but here's the seam weld on my OE tank...

Fuel tank mounts.


i'm kind of guessing here, but it looks to be a machine weld.
 
Good news that it is most likely its original fuel tank.
 
Time Warp said:
Can someone tell if it is a Norton OEM or EMGO tank off the pictures up the thread please.
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I can't answer that, but I can say that current new EMGO Roadster tanks are high-quality and fit correctly. They are heavy steel and baffled like the originals. Generally, I don't like EMGO so don't think I'm some sort of EMGO advocate.
 
There were a few hand gas welded seam tanks a long time ago. The vast majority were pinch roller spot welded (not sure of correct name)Very different and easy to pick out.
The one gas torch hand welded tank I had did not fit well at all and I sold it (with full disclosure) to a guy that had to have it....It was old back then and I sold it 10-15 years ago.
 
I have a 7/73 tank and it's welded on the outside of the seam. The front studs measure 5 1/4" between the base of the studs, the tunnel measures 3 1/2" @ an 1" below the base of the studs and the tank width at the front edge of the studs measures 8 1/4" seam to seam, but looking at the bottom of the tank, the tank has a tumblehome shape so the seams are narrower than the actual bottom.
I can post photos after VIP gets activated.
 
joe czech said:
FWIW, and I don't how much detail you can pick out, but here's the seam weld on my OE tank...



i'm kind of guessing here, but it looks to be a machine weld.
Click to expand...
I just checked two known original 1974 Roadster tanks. The seam looks the same. Here's a picture of the bottom incase it helps. Difficult to tell in a picture, but the area in the red oval widens by 1/4" from the flat area away from you to the flat area close to you in the picture. Hard to measure - I cut pieces of cardboard to fit in both spots and measured the difference.

Looking at the front rubbers you can see that the tank was last installed offset side-to-side and farther back than is should be but it's clear that the studs could have been centered in the frame mounts. The studs measure 5-3/8" center to center..

Fuel tank mounts.
 
while we're on the subject - mignt as well throw in a couple more original OE tank pics -

Fuel tank mounts.


note, i'm "assuming" it's the date code - ??? anybody decipher 269D
I was thinking 269 was a julian date, but it's probably is too late for my Aug 74 build date. the letter "D" - 4th letter - 1974 - ??? - just guessing here....

Fuel tank mounts.
 
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joe czech said:
while we're on the subject - mignt as well throw in a couple more original OE tank pics -



note, i'm "assuming" it's the date code - ??? anybody decipher 269D
I was thinking 269 was a julian date, but it's probably is too late for my Aug 74 build date. the letter "D" - 4th letter - 1974 - ??? - just guessing here....
Click to expand...

I have two known original black Roadster tanks from 1974 MK2s, one from my 1974 MK2A that was originally sold in Scotland, one from a 1972 750 Combat. None of them have a stamp like that. I might be a dealer's inventory number as a spare part unless you know it came on the bike.

Another data point. I have another brand new, beautifully hand pinstriped and painted in 850 style black Roadster tank that I got as a part of a large lot of parts. I have no idea who made it, but it is not baffled and the underside is very different from OEM. It's studs are 5-3/8" center-to-center. The steel is lighter than the current EMGO tanks - I'm guessing India but the quality is better than their usual stuff.
 
marshg246 said:
Another data point. I have another brand new, beautifully hand pinstriped and painted in 850 style black Roadster tank that I got as a part of a large lot of parts. I have no idea who made it, but it is not baffled and the underside is very different from OEM. It's studs are 5-3/8" center-to-center. The steel is lighter than the current EMGO tanks - I'm guessing India but the quality is better than their usual stuff.
Click to expand...

There was a Roadster tank comparison thread (10+?) years ago* which appeared to show some Roadster tanks were better-made than others, some having baffles and some not, but nothing to suggest they were not original.
The quality of my 850 Mk3's tank (no raised front seam) is not perfectly formed in the rear mount areas and it has no baffles.

Edit: This one: https://www.accessnorton.com/NortonCommando/annoying-tank-vibration.1333/
Unfortunately Photobucket now blurs photos of members who haven't paid the ransome-I mean haven't become paying members.
 
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marshg246 said:
I have two known original black Roadster tanks from 1974 MK2s, one from my 1974 MK2A that was originally sold in Scotland, one from a 1972 750 Combat. None of them have a stamp like that. I might be a dealer's inventory number as a spare part unless you know it came on the bike.

Another data point. I have another brand new, beautifully hand pinstriped and painted in 850 style black Roadster tank that I got as a part of a large lot of parts. I have no idea who made it, but it is not baffled and the underside is very different from OEM. It's studs are 5-3/8" center-to-center. The steel is lighter than the current EMGO tanks - I'm guessing India but the quality is better than their usual stuff.
Click to expand...


(hope we're not getting too off topic)

can't swear to the tank being original to the bike when it left the factory. the history of the bike prior to 2006 to me is unknown. I have no reason to suspect it's not original - most of what I'm finding on this bike "appears" to be very original. then again, i'm certainly not a Norton expert.

fairly sure i'm the 3rd owner. when I got the bike it came with most all the original parts . seems previous owners saved most everything -- even the nuts and bolts . problem is, they didn't bag and tag anything!

based on julian date 269, that's September 26th, so from that standpoint, it's not the date code, at least a julian date code, since I have an august build. could it be a paint code, or a unit number (269th tank made)? i'd be interested if any other owners with original painted tanks have similar markings. I would think it could be visible without removing the tank, so, if anyone could check - ;)
 
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maylar said:
Any theory of why it's so far off then?
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I can only assume it was pressure tested when it was painted last, I notice that the bottom of each side where the fuel taps locate checked with a straight edge across them leaves a gap at the outsides of around 6 mm /1/4") which in Joe's picture looks to be flat or near enough to across both surfaces.

The construction quality is very nice, if someone had said it was a modern EMGO not that I have seen one up close I would have had no reason to doubt it (The bike came to Australia before the EMGO was available)

The tunnel is some 100 mm / 4" wide as per this pic.

marshg246 said:
View attachment 12178
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joe czech said:
(hope we're not getting too off topic)
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No such thing Joe.
I keep thinking everything was made at the factory but maybe tanks were outsourced (to fuel tank makers) and even that might have changed or construction methods changed as the numbers needed expanded.
There would be some reasonable machinery needed to stamp the components and do the welding, I keep forgetting it would be in the 10's of 1000's needed plus spares and some guy with a cheese-cutter, pipe and oxy torch was not going to achieve that.
 
joe czech said:
note, i'm "assuming" it's the date code - ??? anybody decipher 269D
I was thinking 269 was a julian date, but it's probably is too late for my Aug 74 build date. the letter "D" - 4th letter - 1974 - ??? - just guessing here....


I have to take back part of what I said earlier. I zoomed in the original full resolution version of the picture I uploaded and realized that they was something in the same place as your stamp. I looked again with the old eyes and saw nothing so I tried wetting it - then I could barely see a ghost of a stamp. Yours starts with a symbol that is maybe an 8, P, B, or even a bear then some space and then 269D. Mine has C8 then a little space, a dot or dash, a little space, 17 then some space and the same symbol your starts with. I'm not 100% on the C or symbol, but the 8, 1, and 7 are readable when wet. Also, I'm confident that each was stamped separately and none of them line up. I recheck my other tanks and still can't find anything there.
Click to expand...
 
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