Tank No1 Trial Fit

Message

D-Rider · #1 Post by **D-Rider** » Sat Aug 22, 2015 10:06 pm

Hi Folks

We've not only reached the phase of having the first tank made (not quite finished - still needs final fettling and lacquering) but we've also had it on a bike for a trial fit.

This first post shows the tank itself and sitting on the bike.

The next post will look at how well it fits.

The third will explain a few features etc.

Here goes with the first:

.... and a few more that I can't seem to link the images directly .... but click the links and you should see them:

https://scontent-lhr3-1.xx.fbcdn.net/hp ... e=5670AF77

https://scontent-lhr3-1.xx.fbcdn.net/hp ... e=56360410

https://scontent-lhr3-1.xx.fbcdn.net/hp ... e=563F30DE

https://scontent-lhr3-1.xx.fbcdn.net/hp ... e=56815EF4

D-Rider · #2 Post by **D-Rider** » Sat Aug 22, 2015 10:54 pm

Next Post ..... a few issues with the fit:

Yes it's close but tank No1 isn't a perfect fit.
The front and rear mounting points are slightly too far apart to bolt straight in to the standard frame mounting points.
It's nothing like as far out as my ethanol-swolen tank but it doesn't quite fit right.
I'm sure it can be sorted with a slight reposition of the tube for the rear mount.

Firstly, the front mount was attached to the tank with it pushed as far back as it would go on it's mounting bolts.

The first pictures show the front mounting bolts in position with the tank pushed as far forward as it will go within the adjustment range of the front bracket. The pictures of the rear mounting show that the rear mounting point of the tank is a little too far back.
Ideally the rear mount would line up when the front mountings are in the mid position of the front bracket.

The next set show things the other way round - the rear mount fixed and the front mounts set as far back as they can be but not back far enough (these aren't so easy to see as you can't get a camera angle straight down the mounting tube):

The final set are showing the tank mounted front and rear using the slotted rear mounting bracket that II use to hold my ethanol-swolen tank.
It's good to see that the carbon tank fits better than my current tank

Carbon tank in slotted bracket (rear mount):

Front mount (nicely located in the middle of adjustment)

.... and for comparison, my own tank in the same slotted bracket .... yep - I've run out of adjustment again .....

D-Rider · #3 Post by **D-Rider** » Sat Aug 22, 2015 11:22 pm

Third Post .... a few other things to mention:

If anything, the photos over-emphasise a few features that people might have a concern about.

Firstly there is the line around the top - sort of where the top meets the sides.

Richard will prep that a bit more to blend it in a bit better and the lacquer will further reduce its appearance.
As it's a line where different mould sections meet, it's just a feature of the part and won't be as obvious when the tank is finished.

The other things that people may have noticed are a few "witness marks" from the stickers on the original tank.
There are 4 of them.
On either side there is the Aprilia tank sticker - the rectangular one from the early bikes (not like the ones on my OEM tank). It's subtle but if you look close you can even make out the word Aprilia within the rectangle .... from just the thickness of the ink!

There are 2 more on the top.
On the recessed crescent there is a slightly raised crescent. It's very subtle - If I'd not mentioned it you might not even notice it!

Finally there is the outline of one of the "world champion" stickers on the top (once again, a different sticker to the one on my OE tank (Aprilia used several at different times).

This one isn't symmetrical and probably the most intrusive (though they don't show that much (photos show them up more than "real life") and lacquer will probably hide them more.

All that said, Richard has found someone to supply sets of all these stickers so they can cover these witness marks.
TBH I may well only fit the World Champion sticker ... but we'll see.

I don't believe these are problems but best that everyone is aware of them.

Viking · #4 Post by **Viking** » Sun Aug 23, 2015 2:48 am

Looking good!! I like it. A lot.

There is also the seam down the rear of the tank as well. Perhaps a tank-protector can hide that?

D-Rider · #5 Post by **D-Rider** » Sun Aug 23, 2015 7:43 am

Viking wrote:Looking good!! I like it. A lot.

There is also the seam down the rear of the tank as well. Perhaps a tank-protector can hide that?

If you never get off the bike, you'll hide it yourself.

Yes a tank-pad will probably do the job ..... I have another Lions-head one squirrelled away for mine.

morepower · #6 Post by **morepower** » Sun Aug 23, 2015 7:51 pm

The seam where the two mould sections meet is the same on the RS250 tanks....

morepower · #7 Post by **morepower** » Sun Aug 23, 2015 7:55 pm

I will get on with tank number two this week and get it over to Andy to make sure any changes I make are correct before I bond the base into place. It will be after the bank holiday but I think it is just a very minor swelling of the pattern tank due to the heat of the resin curing. Vick did all he could to keep the temp down when he made the mould so a 5mm change is almost nothing but is something I will have to allow for on every tank.. Once I have one done then the rest should be spot on as I will be able to make up a template for drilling for the tube.

D-Rider · #8 Post by **D-Rider** » Sun Aug 23, 2015 9:22 pm

morepower wrote:The seam where the two mould sections meet is the same on the RS250 tanks....

Seam on the RS250 tanks

what seam

you're having us on !

morepower · #9 Post by **morepower** » Wed Sep 02, 2015 7:52 pm

Just back from seeing Andy with the original scrap tank and the plastic one.. It seems rightly or/and wrongly the expectation that the bolts would be in the centre of the front plate on the frame.. (rightly from a logical point of view and wrongly from an Aprilia point of view) The two I took over tonight were almost the same and possibly 1 to 2mm different in the plate location but both would fit with no alteration to anything you guys currently have. I think the first test fit tank was my own human error and having no allowance on the tolerance apart from if the tank was to shrink! I can only make a slight alteration to the tanks and move the front inserts back a little to actually give more leeway than the brand new tank currently has.. Andy will be along soon I am sure to give you an update too... I may be making some carbon brackets which will give some adjustment to both the carbon tank and to anyone still using s swollen plastic one.. But that is a little way off and I may send you guys one of those for free when they are done... Partly as a thank you for your patience and partly because I think it will be nice to have a carbon bracket to go with the tank....

D-Rider · #10 Post by **D-Rider** » Thu Sep 03, 2015 1:05 pm

Yes an interesting fitting session last night.
The biggest eye-opener is that with a brand-new standard tank (that has never been used and never seen a drop of ethanol) using standard front and rear mounting brackets, it only just fits.

The front brackets have a large range of adjustment in them but all of that adjustment is based on premise of the tank SHRINKING. There is essentially no adjustibility to accommodate growing tanks. Bizarre (or a design cock-up)

This also makes the front brackets unnecessarily long and if (like me) you have fitted an RSVR yoke set, causes them to foul on the top yoke when you lift the tank.
For some time I've thought a solution to my fouling problem (brackets - not underwear) and to accommodate expanding tanks might be to make a new front bracket. The steel ones we have require a pretty deep pressing - which would be an issue. So when Rich and I were looking at it last night, we came up with the idea of trying to fabricate a carbon bracket. We'll find out in due course whether this is successful and how many of the issues it can actually solve.

#11 Post by **mangocrazy** » Thu Sep 03, 2015 8:14 pm

Yes, now I think about it, even when my Falco was new, there was still precious little clearance (Clarence) on the front mount. What's your vector, Victor?

Sorry. I'm a sucker for an Airplane gag.

Viking · #12 Post by **Viking** » Thu Sep 03, 2015 10:31 pm

Why not just make a new tank bracket from aluminium plate? It would be a lot easier to work with than either CF or steel. (And you can anodise it different colours to suit.)

morepower · #13 Post by **morepower** » Sun Sep 06, 2015 11:32 pm

I have a bracket to copy and to be honest because of how deep it is making an alloy one would be a pain and either be a big chunk of billet and machined or need to be pressed and a tool would need to be made...

So I will see if I can make one from carbon... Just because I can....lol

I have decided to make sure there is no human error to have a pair of bosses made to put inside the mould which are the same size as the alloy tube which is bonded in after it has been made. The bosses will be a two fold thing which will be in the mould to help create the correct size hole for the tube and then when the shell is made be used to locate the tube and be removable too.. Hard to explain so I will post photos when the little bosses have been made and the tube's bore has been corrected to accept the rubber bushes.. Hope it will be done later this week but I am away for my (late) summer holiday from Friday. So I hope I can show you guys what I mean before I go away..

D-Rider · #14 Post by **D-Rider** » Mon Sep 07, 2015 7:19 am

Yes just to echo what Rich has said, the pressing on the bracket is very deep and would be difficult to manufacture from metal in small quantities. CF is the way to go.

Also I'm away from Friday on my summer hols - so luckily we minimise delays on the project by both Rich and I being away at the same time.
I'll be back late on Weds 23rd so any more trial fits are going to have to wait 'till then.

Sorry.

morepower · #15 Post by **morepower** » Mon Sep 07, 2015 11:08 am

The locating bosses have been ordered today and I am sending the tube I have out to have the bore corrected for the rubber bushes. So the initial test fit is done. The "error" is not due to the mould maker or expansion when the mould was made. It is just there is very little tolerance on the inserts. I will try and give the front mount a couple of mm more room if I can. But it is no more than possibly 2mm before the insert would hit the back wall of the tank base.