Board index Flathead Power-Technical Questions, Answers, and Suggestions Big Twin Flatties Replica stock ULH gas tanks...?

Replica stock ULH gas tanks...?

Moderators: Curt!, Pa

Post Wed Oct 15, 2014 8:01 pm

Posts: 469
Location: Six miles East of Cheney, Wa.
Any such thing? I'm only getting about 110 miles out of my knucklehead/Panhead/shovelhead or what ever they are re-pop fat-bobs. But I don't like the looks of the five gallon tanks, or at least I wouldn't like them on my bike which is kind of long low and lean. Just wondering.

Also curious, with the tiny gell cell batteries that seem to work quite well, Seems like a horse-shoe oil tank with a equally tiny battery space would be a worthwhile endeavor, as it would increase oil capacity quite a bit. ?? Just a thought. I suppose a good welder and sheet metal worker could re-do a stock type tank easy enough. Just a thought.

Would like to know if there are replica big twin flathead gas tanks. These are quite indented on the bottom....but I've got plenty of room between the tanks and my cylinder heads. !!!!

Thanks in advance.


Post Wed Oct 15, 2014 8:32 pm

Posts: 86
hey Ken, i have beenrunning a shorai battery in oem oil tank for over a year, SHORAI LFX Lithium-Iron Powersports battery, very compact and powerful. had armature wire break off at generator 100's of miles from home, so dead the tach and headlight had nothing, reattached wire ran two hours and checked voltage...full charge, i think you need to use solid state reg for these guys

Post Thu Oct 16, 2014 5:58 pm

Posts: 216
Location: Georgia
I tried 1 of these in my 1946. It's been there several months. It works well so far.

Post Thu Oct 16, 2014 6:09 pm

Posts: 536
Location: Wa, USA
I am using one of these: In my UL. No problems so far. I have also used a full size Odyssey e-start battery stuffed long way down in a horseshoe oil tank. That also worked, but was a bitch to work on the connections.

Post Thu Oct 16, 2014 7:38 pm

Posts: 469
Location: Six miles East of Cheney, Wa.
Well, actually, the battery Pa suggested is working quite well. What I was getting at, was that with such small batteries, the horse shoe oil tank's oil capacity could be increased quite a bit, if the battery compartment was sized to one of the tiny batteries, instead of big 6V. I failed to communicate!


Post Sat Oct 18, 2014 2:53 am

Posts: 1642
Location: Interlaken, NY USA

Ken, on a big flatty, there's no real reason to increase the size of the oil tank 'till you have a need for more oil to keep oil temps down. With the flow from the stock oil system, the oil won't get hot enough to cause any problems.
Also, from the drift your original post has taken, apparently there aren't any repop flathead gas tanks out there. A shame, as I always thought they had a nicer profile than OHV tanks. :(

Post Sat Oct 18, 2014 6:23 pm

Posts: 469
Location: Six miles East of Cheney, Wa.
I agree, from a side view, the OHV tanks are kind of flat on the bottom, the flathead tanks have a bit of a curve, more rounded shape, and it does look nice. Indeed, I've googled for flathead re-pop tanks and have never got a hit or lead. Was hoping someone here knew something that google didn't. 110 miles sounds like enough range to always find a gas station, but riding South of Spokane, on the out of the way roads and highways, it's not too difficult to rack up 100 miles between gas stops. Many of the little towns don't have a station, or have co-op type pumps where you have to be a grange member or something to get gas.

True, the standard oil capacity seems to be enough...but on a hot day I'm thinking that too much oil can't be a bad thing, and even a few degrees less temp splashing on the cylinder walls might not be a bad thing. On the other hand, on a cool or cold day maybe too much of a good thing. Perhaps more worthwhile if you have piston oilers/squirters, high capacity/flow pumps and modifications and all that. My engine is quite stock.

Well thanks...if anyone has a set of stock ULH tanks in the garage, and would let them go for $100, PM me. :)


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