swollen tank still won't fit!

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dipper
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swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 2:19 pm

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the swollen tank is driving me up the wall! i changed headbearings in less time than its taken to refit the tank... and it's still not fitted! :evil:

even after fitting the MH adjustable tank mounts the tank is still too big. the front mount rubs on the head bearing cover and is @ 5mm too long still. ive tried levering it back but can't get it far enough. i could leave the rear bolts out and maybe tiewrap thenm instead but then the seat doesn't fit!

any ideas?

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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 2:29 pm

Only thing I can think of is to get an offset front mount made up

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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 2:45 pm

Or, grind off the captive nut in the frame, elongate the hole slightly and refit a normal nut. Think that could be the winner!

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No. 47
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Re: swollen tank still won't fit!

Postby No. 47 » Fri Aug 18, 2017 3:11 pm

Put the tank in a deep freeze.............................?
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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 3:20 pm

That did cross my mind. I don't have one big enough unfortunately and I'm not sure how successful it would be. Would probably need doing every time the tank comes off. It's an idea though. New rear tank mounts worked fine on the other bike.

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Re: swollen tank still won't fit!

Postby Sabre » Fri Aug 18, 2017 3:44 pm

Fit the two rear bolts then using a couple of ratchet straps ratchet the tank back into position until the front mounting bolt seats nicely :D Trust me it may seem brutal but it works, Millar suggested the idea when i was struggling with mine 8)
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Re: swollen tank still won't fit!

Postby The Gin Reaper » Fri Aug 18, 2017 3:48 pm

take the rubber bung that fits in the hole that centralises the tank and cut out a section from the stepped down section - put the cut out pointing to the rear of the tank this allows the bolt to be started in the thread as you have some fore and aft slack but as you tighten it down it pulls the tank into place - has worked fine on mine for the last 5 years or so? If i can figure out a picture posting account and you can't figure out what i mean i will try and put up a pic......
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Re: swollen tank still won't fit!

Postby Willh » Fri Aug 18, 2017 4:37 pm

Another way to do it is to unbolt the rear of the tank, install the front by the head bearing first then lever the tank forward from the rear to place the rear mounting bolts.
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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 5:19 pm

Sabre wrote:Fit the two rear bolts then using a couple of ratchet straps ratchet the tank back into position until the front mounting bolt seats nicely :D Trust me it may seem brutal but it works, Millar suggested the idea when i was struggling with mine 8)


That does sound brutal. Not damaged the tank doing that? A strap round each side and pulled back against the rear footrests?

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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 5:20 pm

Willh wrote:Another way to do it is to unbolt the rear of the tank, install the front by the head bearing first then lever the tank forward from the rear to place the rear mounting bolts.


Tried that with no success.

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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 5:21 pm

The Gin Reaper wrote:take the rubber bung that fits in the hole that centralises the tank and cut out a section from the stepped down section - put the cut out pointing to the rear of the tank this allows the bolt to be started in the thread as you have some fore and aft slack but as you tighten it down it pulls the tank into place - has worked fine on mine for the last 5 years or so? If i can figure out a picture posting account and you can't figure out what i mean i will try and put up a pic......


I'll have a look at this. Might be a possibility

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Re: swollen tank still won't fit!

Postby Aphex » Fri Aug 18, 2017 6:31 pm

My tank is also expanded I've never measured how far but it does look as bad as yours.

I've always mounted the front bolt first then used a large screwdriver behind each rear mount while pushing the bolt through until it's located, then I start the threads and do the other side.

Your's must be waaaaay far out for that not to work.
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Re: swollen tank still won't fit!

Postby Willh » Fri Aug 18, 2017 6:35 pm

Aphex wrote:My tank is also expanded I've never measured how far but it does look as bad as yours.

I've always mounted the front bolt first then used a large screwdriver behind each rear mount while pushing the bolt through until it's located, then I start the threads and do the other side.

Your's must be waaaaay far out for that not to work.


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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 6:40 pm

Aphex wrote:My tank is also expanded I've never measured how far but it does look as bad as yours.

I've always mounted the front bolt first then used a large screwdriver behind each rear mount while pushing the bolt through until it's located, then I start the threads and do the other side.

Your's must be waaaaay far out for that not to work.


It is. It was tight before but I managed it the way you describe. The tank was then off the bike a few months and it's grown another 5mm or so. I. Was levering it with a foot long plastic coated tyre lever but had visions of ripping the mount out the tank so gave up

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Re: swollen tank still won't fit!

Postby No. 47 » Fri Aug 18, 2017 6:55 pm

Try levering with a large screwdriver or bar through one rear frame mount bolt hole and corresponding tank hole whilst feeding in bolt on opposite rear mount - once first bolt is sufficiently in place, bolt up other side.
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Re: swollen tank still won't fit!

Postby dipper » Fri Aug 18, 2017 6:59 pm

No. 47 wrote:Try levering with a large screwdriver or bar through one rear frame mount bolt hole and corresponding tank hole whilst feeding in bolt on opposite rear mount - once first bolt is sufficiently in place, bolt up other side.

Been there, tried that. Will need to resort to the more savage methods above i reckon!

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Re: swollen tank still won't fit!

Postby shadowman » Fri Aug 18, 2017 9:24 pm

After a winter rebuild I had the exact same problem.

Tried all the obvious suggestions, bought the MH brackets but nothing worked. I never thought of the ratchet strap idea which I'm sure would have worked.

I was lucky and a mate was able to lever the rear mounts (front bolt started but not tight) while I got the bolts started which I had found impossible when trying single handed.

Looking back, modifying the front mount rubber would have been the best long term fix or if reluctant to cut I'm sure the ratchet strap suggestion would work and is something that would be simple if working alone.
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Re: swollen tank still won't fit!

Postby AGRO! » Sat Aug 19, 2017 1:04 am

Try holding the tank up a bit at the front then line up the bolt with the thread so it just starts to screw in then lower it and screw all the way home.
This used to work for me when I had my SD but I'm in Australia and It seems that with overseas fuel the tanks swell more.

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Re: swollen tank still won't fit!

Postby SUPER DUKE #1 » Sat Aug 19, 2017 2:04 am

Haven't read all of the posts but I removed the standard rear hinge brackets, oval ground the bolt holes as much as possible (I think I substituted allen head bolts so I had more bolt head room?). Then I removed the standard large rubber grommet from the front tank mount and put a rubber hose over the 8 mm bolt as a little protection and with a large fiber exhaust system washer as a cushion under the bolt head and some blue Loctite lightly tightened the front of the tank down. The front tank mount doesn't need to be secured much, just enough to hold in down.

Side note: Decades ago I raced a 24-Hour Endurance road race and we used a stock GS1000 with a stock fuel tank and some teams were already using gravity quick fills. We had three extra stock gas tanks filled with fuel and ready to go for pit stops. The tank on the GS was not bolted down, anywhere, just the fuel line was safety per the rules. Pit stop refueling was quicker than the rider change. Stopped, lifted the hinged seat, cut the safety wire and pulled the fuel line off, lifted the almost empty gas tank off, replaced with one of the full spare tanks, closed the seat, re-safety wired the fuel line and gone. That's why I'm not concerned too much about how really secure the front gas tank mount is on my 990 Super Duke that has way more seat securing the rear of the tank than that GS1000 had. Unless your SD seat flies off I don't think you have to worry how secure the front mount is as long as it has a large washer bigger than the fuel tank hole and just touching. Just my experience.


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Re: swollen tank still won't fit!

Postby dipper » Sat Aug 19, 2017 10:06 am

Sorted. Used the ratchet method. Took way more force than I was comfortable with but no damage done. May try another method next time... which may be very soon as now the tanks on it appears my new(to me) WP steering damper/mounting hardware fouls the tank at full lock/ :evil: it's so far out I'll need to adjust the left lock stop by 15mm which means I'm guaranteed to fall off in a car park! Looks like it was only designed to fit with the earlier tank. looks like the whole top yoke saga(discussed in a previous thread) was a waste of time! :roll:
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Re: swollen tank still won't fit!

Postby SUPER DUKE #1 » Sun Aug 20, 2017 1:52 am

dipper wrote:Sorted. Used the ratchet method. Took way more force than I was comfortable with but no damage done. May try another method next time... which may be very soon as now the tanks on it appears my new(to me) WP steering damper/mounting hardware fouls the tank at full lock/ :evil: it's so far out I'll need to adjust the left lock stop by 15mm which means I'm guaranteed to fall off in a car park! Looks like it was only designed to fit with the earlier tank. looks like the whole top yoke saga(discussed in a previous thread) was a waste of time! :roll:


Any chance you can remove the damper cylinder body clamp angled/offset arm and drill a hole through the top of the clamping split large enough to get an 8mm allen head bolt to go straight down to the tank mount? That's how I mounted my 990 SD's steering damper. No offset on my damper body clamp mount and no lock to lock interference.

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Re: swollen tank still won't fit!

Postby Miff_UK » Sun Aug 20, 2017 10:58 pm

As already mentioned by others, on mine, the front of the tank is touching the steering head bearing cover so HAS to go backwards, (no good just altering the stepped rubber grommet at the front) .
I also removed the original rubbers from the rear mountings and the tank now fits, but the seat is a bugger to clip in.

I left the tank empty over last winter hoping it would shrink back, but no joy.

I wonder if one of those tank sealing kits would help.

Miff

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Re: swollen tank still won't fit!

Postby Aphex » Sun Aug 20, 2017 11:29 pm

Yeah that tanks are absolute shit in that regard. At one point there was even discussion about fabbing aluminium tanks in the same shape but it was to cost prohibited.
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Re: swollen tank still won't fit!

Postby SUPER DUKE #1 » Mon Aug 21, 2017 2:39 am

Miff_UK wrote:As already mentioned by others, on mine, the front of the tank is touching the steering head bearing cover so HAS to go backwards, (no good just altering the stepped rubber grommet at the front) .
I also removed the original rubbers from the rear mountings and the tank now fits, but the seat is a bugger to clip in.

I left the tank empty over last winter hoping it would shrink back, but no joy.

I wonder if one of those tank sealing kits would help.

Miff


I modified the rear stock tank mounts as much as possible to move the tank as far back as possible and you're correct the front of the tank still touched the steering head cover so I ground some of the tank away. I'm pretty sure the front of the tank at the mount hole is solid and I'd bet you could remove as much as 15+mm and still not have any leaking issues. I'll check on this and report back. Has anyone experienced a leak at the front mount??

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Re: swollen tank still won't fit!

Postby SUPER DUKE #1 » Mon Aug 21, 2017 3:41 am

Didn't have a chance to cut the front tank mount yet but did "bore scope" it and it's solid around the front 1/3rd or a little more and pretty sure where one would need to gain some steering head cover clearance. I'll see if my friend still has his old SD tank and if he will let me cut it to confirm it can be modified and not leak.

View from left inside of the front mount area:

Image

View from right inside:

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