F: Frame Fuel tank rear lugs

[Gene Nehring]

 

[vibrac]

All that fiddle is why I use a solid bar with two tapped holes in each end and two hex bolts (1/4 or M6) as bar is alloy it also saves weight

 

[Peter Holmes]

It is not often that I would question Vic's modifications to a Vincent motorcycle, but surely welding additional brackets to the UFM is totally unnecessary, the standard rear tank bracket will take all weight you will ever ask of it, when full of fuel and with a heavy tank bag on top. The only purpose of the T38 and T39 tube and stud is to stop the rearward tank panels from flexing, with vibration and the like, and then fracturing the tank , as was found on the early models. As Bruce has alluded to, this not a precision component, neither does it need to be, you can shorten it, lengthen it with a washer if you previously cut it to short, you can file two grooves in it so it clears the underside of the UFM, you can file a small angled lead on each end to assist fitting, it only has to be a slide fit between the existing tank tabs, none of this is in anyway difficult or challenging, I would even suggest that if you find it so, perhaps a Vincent is not the bike for you.

 

[fogrider]

Vibrac's use of a solid bar with holes in each end is sound, but when I tried to undo mine, one screw came out and left the other stuck in its' threads with no easy way to grip the round bar !
A hexagon alloy bar is waiting for the next time the tank is off.

 

[Peter Holmes]

But why, when the factory solution to the problem was so simple, and it worked.

 

[Vincent Brake]

Bruce, you are quite right: When thinking about that tank support, you better keep in mind to find a way for easy mounting the tank at services. So tonight I had a long look at the design and decided on welding corresponding lugs on the UFM which will have short tube ends with rubber hose inside. So the main weight will go on these and prevent loads on the upper standard tank plate from out-of-center forces on the tank, like from heavy tank bags. Well, not an argument in my case as I will hardly do longer holiday trips - too old for that tiring sports. For that kind of activity there is a 1964 E-Type Coupe´ that just had its TÜV / MOT after sitting 3 years unused in the garage. But then, times are weird these days, CO2 craze, burning cars, Brexit depression in UK, I´d be nervous now having holidays in France, UK and all with the Jag - was a different time only 15 years ago . . .

Vic

I would not be to worried about it Vic, got me a Austin Healy, sticker on it: Using E-Petrol.
allthough we old boiis smell the diference, no one else does.

they all do Thumbs up

 

[oexing]

As already mentioned above I cannot do the original spacer tube stiffener, it would not clear the valve spring cap by about 1/4" , whatever the reason is on this tank/UFM set. So either I mod the tank lugs a lot or have new lugs on UFM welded to align with the tank lugs. So then I don´t have the long spacer below, seems better to me somehow. Still working on all details today for a useful design in real life . . . .

Vic

 

[vibrac]

Bump up the rubbers at the rear under the tank pad that may give enough room also if you use a solid rod you can carve a section out (more weigh saving!)

 

[Cyborg]

For some long forgotten reason, I use 2 rubbers at the rear of the tank. This made the tube touch the lowest plates of the UFM, so I had to file reliefs in the tube. It causes extra fiddling, especially since my tube is short enough to require a washer to shim the assembly long enough for the width between the tank ears.

My guess would be that you used 2 rubber spacers to help align the tank around the oil filler tube.

 

[b'knighted]

Alternatively you could just use a bit of studding with nuts either side of each lug. The reduced diameter should find an easier path through.