Knowledge Base Feedback, Questions on Knowledge Base articles.

Adding fuel range with a VFR tank

Old 04-20-2005, 06:08 PM
  #1  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Adding fuel range with a VFR tank

Here's how I converted a 6th generation (02-present) VFR tank to the SuperHawk. It's not a bolt on
mod by any means so I'll try and break it down via the good (fuel range), the bad (mounting method), the ugly (petcock assembly). This a copy/paste so I apologize for the formatting.


Let's start with the ugly: the tank is for a fuel injected bike and is thus made to contain the fuel pump.
This is the biggest obstacle yet is relatively easy to overcome (hey, I did it!). You need to fab up
two plates that will both seal the large pump opening and be the basis for mounting the VTR's petcock.

Name:  IMG_3868.jpg
Views: 516
Size:  106.4 KB

I used two pieces of 1/8 inch aluminum sandwiched together with a small cork gasket between the plates around
the area of the petcock holes. The 2 bolts for the petcock hold these two plates together. The inner piece is sized to seal the oval opening while the larger
outer unit bolts to the tank pushing the inner plate tight against the oval seal/gasket. Make sense?

Name:  IMG_3872.jpg
Views: 468
Size:  83.2 KB

The three petcock holes (the 2 mounting bolts and the much larger fuel
screen tube opening) are then drilled through both plates. I clamped them tightly together while drilling to keep everything lined up. I initially used a generic cork gasket to form the oval
seal but worried that it wouldn't resist gas over the long run plus it cuts very easily on edges.
It never leaked but I feel much better using the stock VFR gasket as it fits like a glove and is much stouter. It was only
about $4 or so anyway. The piece of aluminum stock I had laying around had reinforcing
ridges which I wanted to keep so I had to turn the petcock slightly from perpendicular to fit between them (in case you're
wondering why it's situated that particular way).

Name:  IMG_3886.jpg
Views: 474
Size:  108.6 KB

I used locktite on the petcock nut/bolts since the nuts are on the inside of the tank after final assembly.

Last edited by superbling; 10-29-2007 at 08:34 PM.
superbling is offline  
Old 04-20-2005, 06:12 PM
  #2  
Hmm?
SuperBike
 
marmaladedad's Avatar
 
Join Date: Oct 2004
Location: San Gabriel Valley
Posts: 2,069
marmaladedad is on a distinguished road
Nice write-up!! How did the tests go with the range of the bike?
marmaladedad is offline  
Old 04-20-2005, 06:15 PM
  #3  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

Here's a pic of the assembly mounted.

Name:  rightside.jpg
Views: 481
Size:  58.9 KB

I had to make a bracket to connect the stock frame mount to one of the mounting plate nuts.
This bracket doesn't support weight since the tank sits on the airbox rather it just keeps
the rear in position and counters the pull from the front mount when you tightened that one down.

Last edited by superbling; 10-29-2007 at 08:35 PM.
superbling is offline  
Old 04-20-2005, 06:17 PM
  #4  
Senior Member
Back Marker
 
call me phil's Avatar
 
Join Date: Feb 2005
Location: mass.
Posts: 140
call me phil
Re: Adding fuel range with a VFR tank

you my friend are [email protected]%#^* brilliant!!!!! quickly patent your idea before someone steals it, takes it to india, mass rpoduces it and makes a bloody fortune!
call me phil is offline  
Old 04-20-2005, 06:25 PM
  #5  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

The bad: The seat/tank junction does not fit correctly with a stock seat. I cut the tank's rear mounting tab
for clearance BUT I DO NOT RECOMMEND THIS. Not only was it sharp but it developed a slight weep that I had to seal up
from the inside. I think one could just hammer the rear tab down to follow the vertical contour of the tank. Another possibility is to cut it down and then have it sealed with a weld. I might do this down the road for more peace of mind.

My corbin seat covers this mismatched joint fine but it causes the seat to sit farther back. I was able to compensate somewhat for this with the corbin's adjustable latch. I still need to get this right but it's workable now.

The stock seat slides underneath the rear of the tank
in the position I have it now (see pic) and with a tank bra looks OK.
superbling is offline  
Old 04-20-2005, 06:27 PM
  #6  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

The tank is not the same size (duh) but the front mount is the same so that eliminates one
problem. The tank is slightly wider (no big deal), longer (big deal) and sits much higher at the rear
mount (very big deal).

The underside/airbox mating is close but different enough that it will not mount
without some major modifications. My "high-tech" solution was a piece of soft wood and a sledge
hammer. Placing the tank on a folded up fluffy blanket in the grass, I slowly dented in the underside where it contacted the airbox,
then place it back on the bike and look for obstructions. The more you do this, the lower the tank will eventually sit. You "might" could use it without doing this but it would look really stupid and the rear would be so high that you'd probably lose a gallon or more of capacity since the petcock would be higher than much of the tank!

This method transferred no dents to the topside surface but I will still say you
run the risk of dents doing this. Be careful. YMMV.

The fuel sensor touches the top of the airbox and it's bolt
threads scratched it up pretty good. Enough to concern me that they would eventually chew their
way through the airbox so I got some cap nuts, like the ones used on the mirror mounts, to cover the threads.

The front mount doesn't sit flush at the steering neck like the stock unit.
I used some longer bolts and spacers to make up the difference. Besides getting the tank/seat junction closer,
lowering the rear tank height also drops the petcock's pickup level allowing for more complete drainage. I think
I have mine at a level where maybe only a 1/10th of a gallon or so is "wasted" when the tank runs dry. Just a guestimation there.

The overflow and vent tubes are located on the front of the tank instead of the rear so you'll need to
re-route those (no big deal).

Unfortunately, I don't have one pic of the underside of the tank. I SWEAR I took one but damn if I can find it now. Next time I remove the tank, I'll make sure to get one and point out the areas I concentrated on.
superbling is offline  
Old 04-20-2005, 06:39 PM
  #7  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

The Good: More capacity!!! Even with the underside heavily dented, I still have 5.3 out of the original
5.8 gallon capacity.

Note: following figures are with a 15t front sprocket but using a sigma computer for mileage readings (although stock odo isn't that far off unlike the speedo)

This gives me anywhere from 175 to 200 miles range (yeah baby!!!!). The VTR's
reserve level sensor bolts right in but it requires re-calibration (fancy term for bending the rod) because
of the VFR tank's different interior contour. I have the RLOD "calibrated" to come on with about 1.3 gallons
left giving me a 50+ mile reserve on the highway. Set at that, my reserve light comes on in 130's instead
of 90 something when I'm running hard (30ish mpg) and in the 140-150 mile range on the highway (38+mpg). On my last road
trip, I frequently filled up with 160-170 miles on the odometer and never put in more than 4.8 gallons!
This range keep me in the same ballpark as the more sport-TOURING bikes on that ride. The final leg
home was nearly 500 miles and I only need 3 fuel stops whereas the stocker would have been at least 5
because of the distances between fuel stations in the remote region.

Name:  odo.jpg
Views: 469
Size:  33.5 KB

Think of it this way, even when I was running 80-85 mph on the interstate, I had over a 2 HOUR fuel range. Even with my VFR bars, lowered pegs, DB screen and throttle lock. I'm ready for a break by that time. :-)

The price. I got a dented tank off ebay for $19. Figure another $50 or so for materials for the plate
and gasket. You can use the VTR's fuel sensor, gas cap assembly, and petcock so there's no
need to duplicate those. I painted it myself although that's not really a requirement but the VFR red really stuck
out on my black bike. ;-) The VFR red on most years is the same as the VTR red (R157) AND the 2000 yellow VFR/VTR are also the same for those of you
considering that route. The biggest cost is time since it's all experimental.

Clearance: It fits on the frame reasonably well and although it's much taller than the VTR it still clears
the taller VFR bars I have installed. It's wider between the knees but you get accustomed to it
after a few hundred miles.

Name:  IMG_3898.jpg
Views: 474
Size:  254.5 KB

Looks: OK, it's certainly not as svelte as the stock tank but you gonna' have to have a bigger bucket
to carry more gas. Personally, I don't think it clashes with the overall styling of the VTR and looks way
better than the huge 6+ gallon morawaki endurance tank which looks very bulbous to me and let's not talk about the $1800 price of admission to that game......

Last edited by superbling; 06-02-2008 at 02:08 PM.
superbling is offline  
Old 04-25-2005, 04:55 AM
  #8  
Senior Member
Superstock
 
ClevelandSuperhawkRumble's Avatar
 
Join Date: Mar 2005
Location: East Cleveland
Posts: 296
ClevelandSuperhawkRumble
oh how naughty
ClevelandSuperhawkRumble is offline  
Old 05-10-2005, 09:52 AM
  #9  
Member
Squid
 
v2weapon's Avatar
 
Join Date: May 2005
Location: Nashville, TN
Posts: 84
v2weapon
Re: Adding fuel range with a VFR tank

Bling, do you think this would work using the stock VFR fuel pump, going to a pressure regulator? I don't know how much the pump outlet protrudes from the bottom, I'd just like to know if it would create clearance issues. I believe using a pump and a regulator would resolve some of the issues with stalling under heavy braking and idling. Supplying consistent pressure to the carbs would keep them well fed, even when the manifold vacuum drops low enough they would fail to siphon from the petcock. It would also help with complete drainage to use the full capacity of the tank.

BTW, this is my first post. I just bought a '98 track 'hawk with road rash on the right side, including the tank. Since I need to replace the tank anyway, I might as well go this route. Thanks for doing the R&D on this! :wink:
v2weapon is offline  
Old 05-10-2005, 06:39 PM
  #10  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

That's an interesting idea. I have three concerns:

1) What pressure would you run?
2) The price. I never see the FI pumps come up used for some reason; very rare and high dollar when the do.
3) Electrical hookup

The pump is fully enclosed with only the in/out line hookups on the exterior so there's even more clearance than with a petcock, so no probs on that front. Check the threads, we had a fellow from down under who's fitted a pump to a standard tank and reports better drainage.
superbling is offline  
Old 05-10-2005, 08:40 PM
  #11  
Member
Squid
 
v2weapon's Avatar
 
Join Date: May 2005
Location: Nashville, TN
Posts: 84
v2weapon
Re: Adding fuel range with a VFR tank

Yes sir, that post is sorta where I got the idea, along with previous experience with drag bikes. Many drag race teams have found that gravity-feed systems, regardless of the flow capacity, usually end up starving the motor for fuel at some point. This shows up as a power hole and a heat spike on their telemetry. By installing a dedicated fuel pump with a regulator they improve consistency, reliability of the motor, and drop their ETs. Since quite a few drag bikes would have an onboard fuel pump for the Nitrous Oxide system anyway, it's not really adding anything unnecessary. Lectron carbs can take 8-9 psi, but I'd probably set the regulator on a 'hawk to around 6 psi and adjust it from there. It's dependent on the tolerance of the float needles.

Yep, those pumps are outrageously expensive. Fortunately my g/f works at a Honda/Kawasaki/Yamaha/Suzuki dealership and I can get parts at 10% over cost. Even so, it's still hard on the wallet for that particular piece.

Electrical hookup? You think up the Superhawk mod of the century, and you'd let a few little wires worry you? :P Seriously though, hooking it up would be a simple matter of splicing the wires into a key-on source with a couple inline fuses for safety. No more difficult than wiring up an alarm system.

I'd really like to see a pic of the bottom of your tank, where you had to apply some "gentle persuasion" for clearance. To be honest, I think the VFR tank has a nicer shape than the 'hawk's. To be able to use that tank with the stock fuel pump to improve the streetability of those big-*** carbs would just be icing on the cake, not to mention bypassing the fabrication of the plates to seal the tank and mount the petcock. (Great job on that, BTW.)

I'll get to work on it and post some pics. I've got my eye on a couple VFR tanks on ebay right now. I picked up my 'hawk on the cheap, but she needs alotta TLC. This is a good place to start. Thanks again for posting your idea and the excellent pics!
v2weapon is offline  
Old 05-11-2005, 06:11 PM
  #12  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

Boy you've got my interest now!

On the electrical issue, I had it in my mind that it was some kind of variable pump controlled by the ECU according to fuel needs. I'm always thinking too much. You make that part sound relatively easy so it seems the most "difficult" part of this is getting one (either used or forking out the bucks for new).

I'm hoping to get some time this weekend to pull of the tank for those pics I promised. It's 3/4's full so there's my excuse to get some riding in! :wink:
superbling is offline  
Old 05-15-2005, 08:38 AM
  #13  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

Here's a shot of the bottom of the VFR tank with indications of the areas where I contoured it to the SuperHawks airbox.

Name:  bottommap.jpg
Views: 477
Size:  132.9 KB

Green is primary, followed by yellow and blue. The white was wasted effort I think. Initially, I concentrated in the yellow section too much and probably took out more capacity than necessary. The blue areas are the vertical sides and also may not be necessary. Lot's of test fittings will keep the amount of denting (thus capacity) to a minimum.

Again, I used a block of soft wood, hammer and/or small sledge hammer to contour the underside. I also used a small id piece of PVC pipe for the fuel sensor area. For that section, I install the sensor and put the pipe around each nut, not on them, when hitting with a hammer. I criss-crossed hitting the four bolt areas just like when torquing a part down. It was my hope that by leaving the sensor bolted in, it would keep that opening level and square thus preventing possible leaks. It doesn't leak.

Word of caution: I got tired while using the sledge and hit the vent tube bending it and had to repair it.

Clear as mud right?

Last edited by superbling; 06-02-2008 at 02:14 PM.
superbling is offline  
Old 05-23-2005, 07:06 AM
  #14  
Senior Member
Back Marker
 
thegreep's Avatar
 
Join Date: Sep 2004
Location: Salt Lake City, UT
Posts: 206
thegreep
Re: Adding fuel range with a VFR tank

How does the difference in width feel? One of the things I really like about the VTR is the width at the knees being narrow. Keep up the development, and I think you may have a winner for any of us that don't like filling the tank every 120 miles.
thegreep is offline  
Old 05-23-2005, 09:01 PM
  #15  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

Yes, it's wider everywhere including between the knees and is quite noticeable the first time you ride it. After a couple of tanks, it feels normal as you adapt. If you want to know how it feels, go sit on a VTEC VFR on the showroom floor.

I let a fellow bmw r1150r rider try it and he remarked that mine was too narrow for his tastes!
superbling is offline  
Old 05-24-2005, 06:51 AM
  #16  
Senior Member
Back Marker
 
thegreep's Avatar
 
Join Date: Sep 2004
Location: Salt Lake City, UT
Posts: 206
thegreep
Re: Adding fuel range with a VFR tank

I don't know if it would work, or if it's any bigger, but there's a cbr919 tank on ebay for anyone interested.

http://cgi.ebay.com/ebaymotors/ws/eB...sPageName=WDVW
thegreep is offline  
Old 01-21-2006, 09:18 AM
  #17  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

Update:

I replaced the stock and corbin seats I had been using with a VFR VTEC seat (02-present) that matches the tank junction MUCH better. The seat is also amazingly close to the VTR in terms of length and width and, to me, in some ways looks more at home on the bike than the stock unit.

Name:  vfrseat.jpg
Views: 471
Size:  200.3 KB

To get it to fit I had to:

add a latch
shorten the passenger section about an inch
use the hooks from the stock seat
fab a front mount for the locking tongues
cosmetic "fillers"
add sargent foam as the stock VFR sux!

This sounds like a lot but it's all simple stuff done with basic hand tools. I then added a stock VTEC seat cowl to finish it off (need to paint of course) as the stock doesn't fit (too narrow). I have it sitting about an inch further foward than stock to match the VTR's lines better.

You can also see the 919 rear hugger and the rear bracket (template) I recently added. I like the looks and the price ($5 ebay). 8)

Last edited by superbling; 10-29-2007 at 09:09 PM.
superbling is offline  
Old 01-21-2006, 10:12 AM
  #18  
Hmm?
SuperBike
 
marmaladedad's Avatar
 
Join Date: Oct 2004
Location: San Gabriel Valley
Posts: 2,069
marmaladedad is on a distinguished road
The bike looks good with the seat!

How flush is the tailpiece with the tail fairing?
marmaladedad is offline  
Old 01-22-2006, 07:38 PM
  #19  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

It's remarkedly close. It's a tad wider overall and longer (remember I cut the seat shorter) so I might trim some off the rear edge of the seat cowl when I paint it. The passenger section of the seat sits higher than stock so I might try to relocate the latch lower to compensate. As is this makes for a larger gap between the two cowl pieces than stock but nothing too drastic IMO. I may leave it as is.
superbling is offline  
Old 01-26-2006, 04:40 PM
  #20  
Les
Member
Squid
 
Join Date: Jan 2006
Location: Tucson
Posts: 93
Les
Re: Adding fuel range with a VFR tank

Interesting but what? 140 miles between stops ain't enough for ya? Don't know about you but after about 100 miles on the bike I'm ready to get off and take a break....It might as well be at a gas station. And I'm out here in AZ where gas stations can be far between.
Les is offline  
Old 01-26-2006, 07:48 PM
  #21  
Moderator
MotoGP
Thread Starter
 
superbling's Avatar
 
Join Date: Dec 2004
Location: South Texas
Posts: 2,553
superbling is on a distinguished road
Re: Adding fuel range with a VFR tank

140miles? WOW, good for you. Me? When I'm ******* it, I can run out at 115 miles with RLOD flickering on in the 90's.

I go on all day runs with other riders who keep that kind of pace all day. They wouldn't like me very much if I had to stop every 90 minutes or so while they all still have another hour's worth of gas! On my last group ride, a guy with a new speed triple was the first to hit reserve; not a superhawk for once! WOO-HOO!!!

Yup, west texas is just like az. A group ride out to Big Bend last spring was the impetus for "project: long range tank". I would have run out twice with the stock tank on our fun route. Sure, I could have ridden the boring interstate by myself, missing out on the twisty backroads everyone else was enjoying, but what would be the point of that?

A larger tank solves one of the biggest limitations of the VTR on the street, IMO.
superbling is offline  
Old 01-08-2007, 11:30 PM
  #23  
Hmm?
SuperBike
 
marmaladedad's Avatar
 
Join Date: Oct 2004
Location: San Gabriel Valley
Posts: 2,069
marmaladedad is on a distinguished road
Originally Posted by fjord View Post
Did anybody think about trying to locate a replacement tank from a Firestorm? It's suppose to be larger than the US version, and I would assume it would fit the VTR with no modification, but don't really know. As for cost, well, that's another story...
In terms of added capacity versus cost, I thought it was a better idea to go with the VFR mod as opposed to shipping a tank from the UK. The UK tank adds only a little less than a gallon, whereas the VFR tank can add up to 1.5 or 2 usable gallons more.

Also, most UK sellers I contacted did not want to deal with the hassle of shipping it to the US, if they even considered it.
marmaladedad is offline  
Old 01-09-2007, 05:36 AM
  #24  
Senior Member
Superstock
 
Birdoprey's Avatar
 
Join Date: May 2005
Location: titusville, fl
Posts: 470
Birdoprey is an unknown quantity at this point
the euro late model gained fuel capacity but gave up some airbox capacity/horsepower, so... you'd have to use their airbox, too.
Birdoprey is offline  
Old 01-09-2007, 02:53 PM
  #25  
Senior Member
Back Marker
 
Join Date: Aug 2004
Location: Belgium
Posts: 203
bluesman
The post-2001 Euro model comes with 19 liter tank but it has nothing to do with airbox. Airbox has not changed at all, exactly same and same capacity. It is only tank shape and fuel tap that have changed a bit. Speaking from experience - I have installed 19 liter tank from 2004 bike on my 1997 without slightest mods to airbox.
You might notice, that in stock state 1997 model is in fact tiny bit more powerful than 1999+ model everywhere, not only in Europe or US (check MO tests etc.) - I guess for "green" reasons or something like that. I think it done by small change in ignition advance and jet sizes.
bluesman is offline  
Old 02-15-2007, 05:11 PM
  #26  
Member
Squid
 
Join Date: Dec 2006
Posts: 31
CB160 is on a distinguished road
www.eti-fuelcel.com/VTR.HTML
They have a 5.3 gal, 7.4# tank made for VeeTar
CB160 is offline  
Old 02-15-2007, 06:11 PM
  #27  
Senior Member
Back Marker
 
azhawk1's Avatar
 
Join Date: Dec 2006
Location: flagstaff ,az
Posts: 154
azhawk1 is on a distinguished road
that tank is sweet ! waaaaayyyyy too much$$ for my blood though!:-(
azhawk1 is offline  
Old 02-15-2007, 09:28 PM
  #28  
Member
Squid
 
Join Date: Dec 2006
Posts: 31
CB160 is on a distinguished road
Ya don't want it bad enuff!
CB160 is offline  
Old 02-15-2007, 09:29 PM
  #29  
Member
Squid
 
Join Date: Dec 2006
Posts: 31
CB160 is on a distinguished road
aRE YOU MARRIED/ENGAGED? WHATJA SPEND ONDE ROK????
CB160 is offline  
Old 02-15-2007, 09:42 PM
  #30  
Senior Member
Back Marker
 
azhawk1's Avatar
 
Join Date: Dec 2006
Location: flagstaff ,az
Posts: 154
azhawk1 is on a distinguished road
we just traded in her rock for her sv 650 better than a ring in my mind .
azhawk1 is offline  

Thread Tools
Search this Thread
Quick Reply: Adding fuel range with a VFR tank


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.

All times are GMT -7. The time now is 06:49 AM.


© 2019 MH Sub I, LLC dba Internet Brands