Project Flying Mongrel – fuel tank questions

[jerry hillman]

Greetings exhalted ones!

I am pleased to announce that restoration of the Flying Mongrel has finally commenced, with a target date of the 2009 Manx GP. Various bits are off to various far-flung corners of Empire, but I need to know a couple of things about my fuel tank, which is of the twin-cap scolloped-sided variety.
Someone at some point has cut down the length of the rod at the rear of the tank, making it too short for my frame. Are the front and rear fuel tank rods one single rod of metal going through the tank, and if so does it serve any structural function?
Second question – are the tank panels welded or soldered together? Has anyone else had this problem and if so have they had any success welding an extra section on the rear without the tank falling apart?

Questions, questions…

Kind regards to all,

Jerry

[dave bushell]

Hi Jerry.
The mounting rod goes the whole length of the tank and should be regarded as structural. The tank is soldered, so be very careful if you try to extend the rear mounting. I need to do the same to one of my tanks, but at the front. As yet I haven’t plucked up courage to tackle it. I may try for a purely mechanical solution.
Dave

[Steve Bowles]

Hello Jerry,
8)
If it helps I have a spare one in primer which I believe to be sound – ring me on 02392 619369 if you are interested….Steve

[jerry hillman]

Dave/Steve,

Thanks for your kind suggestions/offers. I am going to take the tank down to a local classic bike nut who runs a welding shop here in Brentford. He may be able to help, as I’ve found out only today about some sort of plasticine-like material which soaks up the heat from a weld and stops it transferring to the rest of the metal. If it works I’ll let you know Dave – if it doesn’t I’ll be giving you a ring Steve…!

Kind regards,

Jerry

[jerry hillman]

Further to my last, my welder friend reckons it can possibly be done – but when it came to measuring up something occurred to me.

The distance between the front and rear tank bolt bolt holes is exactly 25″.
The tank itself is 20″, and the distance between the front of the tank and the mounting bolt hole on the rod is 1″.
This means that there is (would be when welded) a 4″ gap between the rear of the tank and the rear mounting bolt hole on the frame.

Is this normal? Have I got the wrong size/length of tank or do ‘they all do that sir’?

All pontification gratefully received…

Regards, Jerry

[chris wastell]

hello Jerry. I am certainly no expert and don’t know a lot about Scotts but there are definitely different legth tanks and frames. You must have the longer frame.

[Erik]

Hello Jerry,

I did some measuring on my Scott (in parts as it is at the moment…)

Distance between the mounting holes 25″
Distance between tank front and front mounting hole 1″
Distance between tank rear and rear mounting hole 1,3″

So it appears that you have a rather short tank!

My frame is the short Flyer version.

Cheers,
Erik

[jerry hillman]

Dear all, many thanks for your wisdom.
Erik, when you say 25″ between the mounting bolt holes, is that on your tank or on your frame?

No rebuilding today, we’re playing in the snow here!!!

Jerry

[Erik]

Well, as my tank fits the frame I would say BOTH!

Erik

PS very snowy here too in Holland…

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