Bike frame as a fuel tank, has anyone tried this?

[ocscully]

Observations On Felt Framesets

This afternoon i've had the opportunity to see both the Felt MP (Steel) and a Vintage Iron 400 (Alu.) in person, and want to pass along some insights gained from seeing both of these bikes side by side. First) the volume of the tank on the Alu. frameset is probably twice (approx.) the volume of the tank on the Steel frameset. When viewed from the side the two tanks look very similar but when viewed from overhead the Alu. tank is 2&1/2in. - 3in. wide where the steel tank is only 1&1/4in. - 1&1/2in. wide.
Second) the faux gas cap on the Vintage Iron 400 is just a 2in. dia cap with a 4mm threaded post on the bottom that screws into a rev nut/braze on on the centerline of the tank. Third) the Vintage Iron 400 has brackets welded to the seat tube to mount the side number plates that might be a problem for routing the motors drive chain/belt.

 

[itskeith]

Quest for Felt

Oscully,

very interesting information about the width of the (tank) tube and other observations. Wow, that is a big difference indeed. Those MP bikes are harder than hens teeth to find. I have located a 2006 model about 90 miles from here, and I might have to take a look at it. The issue I am mulling over now is how to fasten a bushing for the fuel petcock and tank gas cap, to the bike without ruining the finish. Most folks I talk to about these bikes say they are powder coated which should withstand heat better than paint. I found a special brazing rod that seems to work will with a minimum of heat. Take a look at this page and watch the video.

http://aluminumrepair.com/aluminum_repair.asp

Pretty amazing what they are doing with this HTS-2000

I think I would get some practice aluminum, powder coated pieces to practice on. I also same the same rod on E-bay for a lot less than the starter pack on the HTS-2000 site.

Well the quest goes on but not until my days off next week (t,w,th). Thanks for your helpful observations. I would have been an unhappy camper to order the steel bike and find the tank was too small to convert.

Keith

 

[vintagebiker]

After reading your post I looked at the Felt web site.
They offer the aluminum frame as a bare frame kit, no paint or powdercoating on it.
That might be the way to go instead of ruining the finish of an MP bike.
I think it would be almost impossible to weld-braze-solder threaded fittings on without damaging the finish.

If you go the aluminum route, there is a sandrail shop in Anaheim, Ca. that sells aluminum threaded filler bungs and caps for aluminum gas tanks. You could start with a bare aluminum Felt frame and have someone who is a really good aluminum t.i.g. welder install them so it looks really clean.

Just my 2 cents.
Good luck what ever method you chose.

 

[ironwarlock]

Why do you have to weld anything? just drill and tap the tank.you have no real pressure points where you will be taping. It will be clean cut and no finish will be wreck't. If you wanna pull out the welder, ya might as well just build the frame from the ground up. .

 

[ocscully]

Felt Tank Volumes

Keith,
I would not go so far as to say that the tank on the steel frameset is not usable, its just the the volume it would hold is approx half as much as the Alu. frameset. There is a guy here in OC that has sealed up the toptube on a Nirve Chopper to use as the fuel tank for his motor, and i'm sure it has even less volume than the Felt MP. The owner of the Nirve Chopper is a member of this forum. I believe his avatar is Blaze and there is one or more photos of his bike in the gallery. I'm going to try and get by the shop again this afternoon with the Felt Crusiers and take some photos of the two different tanks from over head and post them with the previous photos of the 1903.
I watched the video on the HTS-2000 and agree with you that its pretty amazing. I didn't know such a product existed.
Scully

 

[ocscully]

Photos of Felt Tanks

Keith,
I made it to the shop that had the Felt cruisers, alas they had sold the MP model but had othe models with the steel frameset available for comparsion. There are 2 views of the steel and alu. framesets side by side viewed from overhead, and 2 views of the faux gas cap on the Vintage Iron 400 Alu. framset.

Photo Link: http://groups.msn.com/Feltmotoredbike/shoebox.msnw

Sorry, I still haven't figured out how to make the upload picture button/feature work

Scully

 

[itskeith]

Stalled out!

Here I am stuck in Yreka, CA. Been on duty going on 14 days due to fires in the area. I would really like to start on my MP bike but days off are not in my forseeable future. One thing I did find out about the Felt MP bike is that they are "wet painted," instead of power coated. This makes it a lot easier to repaint after perhaps adding the filler and bung. I found this out by emailing Felt and although it took a while for them to reply, at least they did. Thanks to all for the help and pictures but it is going to be awhile before I can actually get started.

Buzz along,

Keith

 

[mini-pub]

fuel cap and vapor lock

I own a Felt MP and I mounted a 3-speed stick shift to the right of the tank by the front forks. It is a sweet ride and definately turns heads.

I just bought the Felt Taxi from Floyds Bike shop in Santa Ana. He had a friend weld the tank holes so it could be used for a tank. It looks like it will hold about a half gallon. I am going to also mount a small half gallon cylinder shaped tank behind the seat as a reserve tank.

Question to those out there that have made their own tanks. Does the gas cap need to be ventalated? If the carb is sucking the fuel out of the tank, I would think that there needs to be a way for air to vent into the tank otherwise the pressue would prevent the fuel from flowing.

 

[jpilot]

Question to those out there that have made their own tanks. Does the gas cap need to be ventalated? If the carb is sucking the fuel out of the tank, I would think that there needs to be a way for air to vent into the tank otherwise the pressue would prevent the fuel from flowing.

Yes, the tank must be vented, otherwise it will form a vacuum as the fuel is used and fuel will stop flowing.

Another major consideration is some type of protective coating inside the tank. You must coat the inside of the tank with a protective coating to prevent rust and the coating has to be impervious to fuel. I've used a product call Kreem on motorcycle tanks with good success. The Kreem not only prevents rust but will seal any small pinholes in the welds to prevent leaks.

 

[Roy Carpenter]

If those holes are visible, then it would be easy to seal them with some JB Weld or something. You might drill out a hole in the top....possibly try to solder, or weld some sort of sleeve into the hole, and use a boat plug for a cap...lol. Hey..it would work...lol.