Originally Posted by rmak
I think a 60's tank might be easier than what looks in the photo to be a 70's T140 tank. The 60's tanks had spaces for the coils underneath just like the moderns. 70's Triumphs had the coils under the seat and the channel was very narrow. Also, 70's tanks were held by a screw in the middle coming up from the frame where a 60's bolted in the back, like the Hinkleys.
the 70s tanks are oil in frame tanks and so the frame spine is wider than the 60s so while the earlier tanks have the space for the coils they narrow towards the back where the 1971+ tanks have a consistently wide channel. I seriously doubt either channel would be wide enough for the Hinkley frame though.
If you really wanted an older tank maybe you could perhaps take an older tank, cut out the bottom and remake and weld a suitable bottom to it. I think though it would have little fuel capacity but that may not be an issue if looks are the main priority.
An other alternative is to make a tank from scratch eg using techniques shown in: http://www.millerwelds.com/resources...ks-Ron-Covell/
That would be a pretty serious undertaking though but achievable. (I actually bought the DVD of tank building by Covell - maybe one day when I get the time I will have a go at building a tank)
My recommendation if you really like the old tank shape would be to do what I did, buy a complete old bike which has the tank shape you like, fix up the bike and ride that**
FWIW The 1971+ OIF tanks look like this underneath
the earlier tanks look like this:
** I actually think putting the older tank on the newer bike, from a look wise POV, may not work that well. The bikes have different sizes and lines and I have a hunch you will find it will look slightly forced rather than natural. The bike you show, to me, seems to have a slightly too small tank for the size of the bike but everyone's tastes vary - that is just the way I'd see it and it is your eye that matters on your bike. That said Sayonora's T150 tank seems to work visually. Maybe the T150/T160 tanks are physically bigger than the Bonneville ones.