RGM new Interstate tank

Hi,

I'm interested in getting an Interstate tank. RGM stock a new fibreglass one, 'Very sturdy, made in UK using special resins that are 100 % ethanol proof'. Was wondering if anyone has had experience of these? Cost is 430 pounds, so adding freight to NZ and paint makes it expensive if there are any future issues.

They also recommend using 'Slosh' from Rustbuster as a sealant. Looks good on their website but doesn't appear to be sold in NZ. Anyone tried this?

Thanks,
Graeme.

Mmmm. That's a lot of money for a fibreglass tank. Are they still legal in NZ? I'd check with VTNZ.

I think TAB in Wales make a aluminium one although an Interstate tank is heavy when full of fuel and you would really want to check the mounting is very strong.


If you do want to try a liner available in NZ use POR 15. I lined a rusty roadster tank with POR 15 about 4 years ago and it's been fine with NZ 95 petrol.

johnm said:

Mmmm. That's a lot of money for a fibreglass tank. Are they still legal in NZ? I'd check with VTNZ.

I think TAB in Wales make a aluminium one although an Interstate tank is heavy when full of fuel and you would really want to check the mounting is very strong.

If you do want to try a liner available in NZ use POR 15. I lined a rusty roadster tank with POR 15 about 4 years ago and it's been fine with NZ 95 petrol.

Click to expand...

The Tab aluminium one costs 680 pounds plus freight. Their welder died in a recent IOM race so could be a while till production restarts. I've only seen old fibreglass ones on Trademe, don't want to take the risk of importing an Indian one.

Seems strange that they recommend applying sealer to a '100%' ethanol proof tank....

I see there are hundreds of tanks made in India for our bikes for far less money
Are they really that bad?
What advantages do fibreglass tanks have over steel ones?
Why were fibreglass tanks initially used and then banned?

As an aside, I remember my disappointment 40 years ago when I at last saw a JPN replica for real in a bike shop and saw how badly the fibreglass moulding had been plonked over a rough steel tank with a few bits of foam rubber between the two. I lost interest though I wish now I had bought it anyway. I still think they are a stunning looking bike and I’m sure I could have improved the poorly executed setup
Alan

Alan L said:

I see there are hundreds of tanks made in India for our bikes for far less money
Are they really that bad?
What advantages do fibreglass tanks have over steel ones?
Why were fibreglass tanks initially used and then banned?

Click to expand...

Fibreglass tanks were banned in the U.K in the early 70's after some incidents where the tank split open, and riders were killed.
Tanks from India are a bit of a lottery, some are just OK, whole others are outright crap.

Alan L said:

I see there are hundreds of tanks made in India for our bikes for far less money
Are they really that bad?
What advantages do fibreglass tanks have over steel ones?
Why were fibreglass tanks initially used and then banned?

Click to expand...

Fibreglass tanks rupture more easily in a crash, with a larger fire hazard.

They are also weakened and leak with Ethanol laced fuel.

I think the way to look at Indian tanks is to consider them as a start point rather than s a finished product. Don't bother getting a painted tank for example. I bought a T160 Indian tank on Fleabay once, the UK seller had a money back guarantee so I thought I would try it.
When it arrived, the tank had obviously been pcked in bubblewrap before the paint was quite dry, leaving an interesting pattern of marks. Rather a pity actually, since the pinstriping ( the really hard bit) was quite good.
When I test fitted the tank, the petcock holes were placed too far back, meaning that any type of petcock was going to hit the carb gantry. Fixing this means removing the existing bosses, welding a patch, cutting a new hole & welding new inserts, then leak testing, then painting again.
I chose to return it.

Regarding fiberglass tanks, I have a PR tank (again off fleabay) which I lined with Caswell. So far (after 4 years of E5) it seems ok, but I'm not 100% confident in it, so at the moment its wearing a rattle can coat of black. No point in spending money on a good paint job if the tank bubbles up.

There was one good Indian maker of Interstate tanks who pressed the top in one piece instead of the normal patchwork of scrap steel. Shape was good and good reports but not seen his product in a few years.

I bought a painted Indian tank 3 years ago $400.00 US delivered to my door. I was very excited as the paint and Pinstripping looked good.All that went away when I put it on the m/c.All the mounts were off by a 1/2”.I had to have the tank cut in the front so it would slide up enough to clear the handlebars and reworked the mounts.This work doubled the cost but has held up for quite a few miles.
If I had to do it again, I would just keep looking for a factory steel tank in usable condition.Too much of a crap shoot and the dealer in India was worthless.
Mike

Alan L said:

What advantages do fibreglass tanks have over steel ones?
Why were fibreglass tanks initially used and then banned?

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1. The cost of the tooling/moulds is significantly less for fibreglass over steel.

2. Cheap and then found to be lethal.

kommando said:

1. The cost of the tooling/moulds is significantly less for fibreglass over steel.

2. Cheap and then found to be lethal.

Click to expand...

Particularly for low production volumes, GRP tooling probably is well under 1/10 of the cost of doing it in steel, but the production process is more labour intensive. After banging out the top & bottom halves from sheet steel, they have to be welded, cleaned and painted.
GRP requires that the gel coat be laid down, then the glass matting, then more resin. When the 2 halves are cured, they have to be joined with more resin. No need for painting though, since the colour is in the gel coat - unless you want more than a single colour that is...

The modern equivalent of GRP is the blow molded plastic tanks, which have their own problems with modern fuels. Ducati were well known for problems here, and there's a long running thread on the 961 forum on replacing tanks as well. lots of bikes today have very complex shapes which are difficult to do in a simple press tool, and the costs climb steeply when you get into the more complex tooling forms, so there's a lot of motivation to use other methods.
Perhaps it will all go 3D printed at some point.

Oh, I forgot - future bikes will be electric, so no need for a tank at all