The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: DgM on August 10, 2009, 12:46:48 PM

Title: Gas Tank Mod
Post by: DgM on August 10, 2009, 12:46:48 PM

To make use of the gas carried in the right side of the gas tank on my 1983 R65, I picked up a used gas tank on eBay from a R65 LS, had it strip dipped (no rust!), brazed a bung from a donor tank, did a bit of grinding, smoothing, priming, now have twin petcock ready gas tank. Black paint is temporary to seal primer until final prep and paint.

Title: Re: Gas Tank Mod
Post by: DgM on August 10, 2009, 12:48:02 PM

photos...

Title: Re: Gas Tank Mod
Post by: DgM on August 10, 2009, 12:48:36 PM

photos 2

Title: Re: Gas Tank Mod
Post by: Bengt_Phorqs on August 10, 2009, 12:53:37 PM

Brilliant!

Title: Re: Gas Tank Mod
Post by: DgM on August 10, 2009, 12:59:06 PM

smooth photo

Title: Re: Gas Tank Mod
Post by: DgM on August 10, 2009, 01:24:55 PM

Thanks

Title: Re: Gas Tank Mod
Post by: Justin B. on August 10, 2009, 01:56:28 PM

Excellent, that's the way the factory should have done it - or at least put a crossover tube between sides like my old Honda had...

Title: Re: Gas Tank Mod
Post by: DgM on August 10, 2009, 02:03:18 PM

I'm going to run fuel line from right petcock to a 't' fitting as on left side, short line to carb, utilizing crossover gas line as balance pipe.

Title: Re: Gas Tank Mod
Post by: R65Singh on August 10, 2009, 11:31:50 PM

Excellent job!!!...looks really neat.  BTW how u did that strip-dip thing?  Is it some sort of chemical wash?...I am planning to repaint my tank and it might be a good idea to strip to the bare metal before repainting.  This site is a big help...keep up the good work.

Title: Re: Gas Tank Mod
Post by: Bengt_Phorqs on August 11, 2009, 07:50:53 AM

Quote

I'm going to run fuel line from right petcock to a 't' fitting as on left side, short line to carb, utilizing crossover gas line as balance pipe.  

Yep, just like on the big boys.  Are you using a BMW petcock with the screen filters inside the tank?  Be sure that you use the ethanol resistant fuel line.  Justin has a thread on here somewhere about fuel line.

Title: Re: Gas Tank Mod
Post by: DgM on August 11, 2009, 12:55:32 PM

I had tank stripped to bare metal by L&M in Van Nuys, Ca in their hot acid bath.  Inside and out clean as a whistle.  Toxic.  BMW badges sort of melted after falling off.  Planning on using BMW petcocks with screens.

Title: Re: Gas Tank Mod
Post by: bjamesw on August 11, 2009, 12:55:53 PM

Ever seen those "jiggler" fuel siphon hoses?  I saw one on the shelf at Menards last year and a little bulb lit up in my head, but I never pursued it.   Seems like a miniature version of this, well encased in rubber, in the shape of a "U", and sufficiently weighted at both ends to keep it in place, would be a cool aftermarket item for all motorcycles with deeper saddle tanks and single petcocks.    Just the bouncing and jiggling of the bike in motion would constantly be working the ultra simple little ball bearing pump inside of this "jiggler" siphon and be moving gasoline from the untapped side of the tank to the other.   It would siphon very slowly, but sufficient to drain the non tapped side dry by the time the next fillup was necessary.  

Title: Re: Gas Tank Mod
Post by: invincibleone on August 14, 2009, 12:14:50 AM

Sooooooooooooo, DgM, any interest in possibly making this mod for a few fellow R65 riders? I think you have found/created a market niche. Nice work man.

Title: Re: Gas Tank Mod
Post by: DgM on August 17, 2009, 10:55:02 AM

Thanks again for compliments.  Any R65 tank can be modified.  How many amongst you would want mod?  

Title: Re: Gas Tank Mod
Post by: Bob_Roller on August 17, 2009, 11:16:21 AM

Are there fittings available, without having to 'cannibalize' a donor tank to accomplish this modification ?

Title: Re: Gas Tank Mod
Post by: DgM on August 18, 2009, 11:46:14 AM

Don't know where fittings would be found.

Title: Re: Gas Tank Mod
Post by: weasel01 on August 21, 2009, 10:42:07 AM

Was the stripping process expensive?

Title: Re: Gas Tank Mod
Post by: DgM on August 22, 2009, 11:19:55 AM

Stripping should be the price of a couple fill ups of gas - for your R65.  Stripping removes EVERYTHING not metal on tank, including factory touch up materials.  Inside tank is spotless as well.  Less distortion of metal than sandblasting.  However, as EVERYTHING is removed from tank, you should work quickly on prep / sealing or surface rust - inside and out - will set in.  My tank is at painter, should be ready in a couple of weeks.  If my R65 was modified / stripped down I would have just polished it.