[broomstick]

As this seems like a topic that would have been covered here before, I did a search and found nothing, so hopefully I'm not repeating anything.

Anyway, I'm building a hardtail from a '69 TR6 and love the look of the oil tanks on the Pre Unit rigids. What's the story on fitting one of these bad boys on a Unit? Does it just depend on the size of the Unit's hardtail section? Would it have to be a tank from a rigid, or would one from a swingarm Pre Unit fit? I've seen oil tanks from Cubs made to fit onto Unit hardtails too, is why I ask.

What about the capacity and the plumbing, being a little smaller than the Unit tank--is this an issue?

Thanks for any insight.

 

[rustirpyles]

Most bolt on hard tails have a bit of stretch to to them giving them a bit more room inside than the factory installed ones, so you can run just about any early preunit oil tank in one. As to volume, I have seen some pretty small oil tanks on unit trumps that ran for a really long time. I don't think a cub tank would hurt anything. I'm sure somebody out there will disagree though.

 

[need louvers ?]

The problem with the pre unit ridgid tanks though is that the they have a sort of forward "cant" to them that doesn't look good with a unit's straight seat post tube. If you look at the ridgid pre unit bikes, the trans is behind the seat post tube and the tube is layed forward. In my opinion, the Cub tank really looks the best on a unit bike. I've been doing the same thing lately with my '61 Triumph after putting a 2" over hard tail on it, space is at a premium. Oh, the swing arm pre unit tanks don't have a shape that lends them selves well to a hard tail application either.

 

[BikeVice]

Cub tanks look great, but they only hold 1 1/2 quarts of oil vs. about 3 quarts for a stock unit tank. In one of the build threads, somebody extended the back of a Cub tank a few inches to gain some more capacity. Maybe they'll chime in.

Eric

 

[broomstick]

Cub tanks look great, but they only hold 1 1/2 quarts of oil vs. about 3 quarts for a stock unit tank. In one of the build threads, somebody extended the back of a Cub tank a few inches to gain some more capacity. Maybe they'll chime in.

Eric

I saw that thread with the extended Cub tank on here a while back. Looks great, but unfortunately I don't have any fabricating/metal working skills (makes building a bike that much more difficult...) to do the same. Good to know on the capacity, thanks.

Need Lovers--I see what you mean now about the forward "cant". I don't think it looks too bad, but you're right, the cub tank looks better.

 

[Ryanm]

check out this thread http://www.jockeyjournal.com/forum/showthread.php?t=46842 it is lurkingclass bike and I think it looks bad ass with the preunit tank. I put a cub tank on my bike and it would overheat with the amount of oil in it. I have since put a preunit tank on it
Ryan

 

[need louvers ?]

In the side view on page 2 of Lurkingclass's thread, the pre unit ridgid tank doesn't look too bad. Ironically, I pulled every tank I have out of hiding around here to mock mine up and a tank very similar to the first one he had on that bike won. It's an old Santee horseshoe type that came with a basket case ten years ago and has never had oil in it. I had to trim it a bit here and there where it couldn't be seen to fit with the short tail, but damn it looks good.

 

[broomstick]

The pre-unit tank looks great on Lurkingclass's bike. I was also checking out the tank in SpeedAndNoise's post, toward the bottom of the page HERE. Looks great, although, a little empty on the other side. Need Louvers, I also like the horseshoe style for this reason.

Thanks for the input guys.

 

[vorhese]

Mine
http://vorhese.blogspot.com/2010/06/expansive.html

Another link with all the pics
http://geekbobber.blogspot.com/2012/08/cub-tank-adaptation.html

I actually redid (WITH HELP) it from this first time, because my attempt at brazing sucked so bad

2nd attempt:

 

[broomstick]

Vorhese--that looks great, man. Digging the bike in general. Did you ever figure out a cover for the other side of the tank?

 

[need louvers ?]

Broom stick, I hope you don't mind a little Highjack here, But Vorhese, that's bitchin'! You and I have to some of the few messing with duplex bikes. What is the stretch and drop on your tail?

 

[broomstick]

Louvers--Highjack away; I was wondering the same thing.