Is There A Law That Says Reproduction Parts Have To Be Junk?

I spoke too soon about the quality of this reproduction Norton tank being decent. Inspecting it side-by-side with the original, you can see the problem. The dimensions are barely the same, the shape is barely the same. The seams are terrible. Especially that front seam. What am I supposed to do with that? I can smooth it slightly, but if I go too far, it’ll open the seam up. I have the top seam almost resembling the contour of the original after tearing into it for a straight hour with a body file. I was hoping not to use any filler on it but I don’t think I have a choice in a couple spots.

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Oct 12, 2026

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Replies (25)

· 1w

I'm guessing most people have no idea of the work it takes to make something like a motorcycle gas tank and don't want to pay what it would cost so "barely good enough" gets purchased. Then the pain is distributed over time by paying to make the "barely good enough" into a suitable item. Never mind that it would have been cheaper to buy a well-made unit to start with.

· 1w

I told the story of the battery box in your last topic on this subject? Box is rotten, shop fabricates a perfect reproduction for 350 bucks. Customer flips and says you can buy a reproduction for 150 bucks. Reproduction shows up, galvanized steel, won't fit. Final bill is more than the first box and the reproduction is a piece of crap.

· 1w

You know it’s bad when you can actually see in the photo that the saddle in the center of the tank is wider on the repop. No measuring tape needed.

· 1w

How are you going to deal with that? Or ignore it because it fits anyways?

· 1w

I’m just going to ignore that. It shouldn’t be noticeable once it’s mounted on the bike.

· 1w

Not surprising. There is a reason NOS stuff brings so much more money than reproduction junk.

· 1w

If a reproduction part is identical in every way.. its perfectly fine but you will pay for it. My Doble is having a full mechanical overhaul in Isle of Man. Chris Wedgwood is an expert machinist and his parts are possibly better than the original.. The only pain is in my wallet! 😜.

https://doblesociety.com/forums/2021/topics/28119/doble-auxiliary-unit-progress

· 1w

I would agree with “better than original” in that case, for sure.

· 1w

It is amazing what you can accomplish with an unlimited amount of time and money. And patience.

· 1w

Bought some reproduction quarters once. By the time we got them to fit it would have been easier for me to drive to Arizona and cut a nice pair off a car in the junkyard and drive home. At that time I lived 1300 miles from Arizona.

· 1w

Been there.

· 1w

When I was restoring my Shelby you could still get NOS sheet metal for 69/70 Mustang. So the trunk drop offs and a few other parts were NOS. The torque boxes were reproduction. They worked but in the end you almost which you cut up a rustfree car to get factory ones.

Almost always the NOS stuff is 2x better. I've seen mustang upholstery kits that were very nice but you need to pay for them. There were cheap kits too.

· 1w

This is why a fine point Model A differs from the vast majority of restored "A"s. Back in the 60s - 80s it seems every town had a few in process making for a boom in the junk parts industry. US made is genetally better but no substitute for NOS. Of course @DuesyGuy likely doesn't have a thick Doble parts catalog...

· 1w

It seemed like in the 80s there were dozens of Model A Ford parts suppliers. Every state has one. Many are gone.

· 1w

@rjones exactly! The owner of A&L Model A lived across the street from us - we moved in in 96 but I understand 60s - 80s there were quite a few As in our neighborhood. Kind of an anomoly but still..

· 1w

I'm very grateful for the suppliers we still have. My only peeve is, every vendor sells the same parts from the same suppliers and if those parts are junk then everyone's parts are junk.
I also understand that guys like me are a shrinking market so I'm just happy to be able to get -something- I can work with.

· 1w

Fair enough Shawn. We won't know how much we miss them until they are gone.

· 1w

Cue the sad trombone. I spent a couple more hours grinding, shaping, smoothing, and sanding and it was shaping up fairly well. Then I noticed one small split in one of the seams. Looks like it’ll need to be TIG welded up to make sure there are no leaks, then I can finish getting it ready for primer. And this tank cost $650. 🤬

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· 1w

Kind of unforgivable in a gas tank. Imagine if you didn't notice and it was painted and installed?

· 1w

I guess it would have remained sealed, had I left the very rough weld on that seam. Clearly the weld didn’t penetrate well enough to allow for any smoothing because I barely took any material off before it opened up. If it weren’t a gas tank, I’d MIG weld it myself but since it has to be fuel tight, I’ll let the welding shop up the street TIG it and it should be fine.

· 1d

I got the tank back from the welder. It was a good idea having them do it because it was a lot cleaner of a job than I could have done with a MIG so there was minimal cleanup to get it ready for primer. Being a fuel tank, I really didn’t want to use filler on it so I spent extra time metalworking. Only needed filler in a couple tiny pits in the steel. I also finished it fine enough that I didn’t have to use high build primer as I prefer to use epoxy primer where gasoline could get on it. I have it a few coats of epoxy on the outside and one coat on the underside to seal it before base/clear on the bottom.

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· 1d

Today I block sanded the epoxy primer and overall I think it came out straighter than I was expecting. After I primed it, I saw a couple problem areas but I was able to get them smoothed out well enough without a reprime. A couple minor sand-throughs were sealed with a light coat of epoxy before spraying the basecoat. It was baked and will sit overnight so it will be good and dry to put the decals on…as long as I don’t mess up them or my basecoat in the process. It’s a nerve-wracking thing, putting decals on before clearcoat, but the final product is so much nicer. I’ll probably put three coats of clear on so I have a little extra material to smooth the outline of the decals a bit.

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· 1d

Agreed on the decal but it makes it a lot more complicated, doesn't it? Looking forward to seeing the finished product.

· 15h

So, we’re up to plan B, or C, or maybe even D at this point. I put the decals on the tank this morning. The vinyl backing gave me some difficulty removing and it took some doing to get the adhesive to stick properly. Both signs that this was either very old vinyl or it was just very low quality. They looked good at first but after letting it sit for a few hours, the vinyl was full of bubbles that refused to stick. After much profanity and questioning of my life choices, I decided that the only reliable thing to do is remove the decals and clear the tank beforehand. I’ll recommend that the customer has some new decals made from high quality vinyl versus this stuff which has probably been sitting on a shelf for 20 years. Not my ideal way of doing it but it still came out nice.

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· 13h

If it were easy, everyone would be doing it.