BMW G650GS Auxiliary Fuel Tank



+ Reply to Thread
Results 1 to 7 of 7

Thread: BMW G650GS Auxiliary Fuel Tank

  1. #1
    MarkR's Avatar
    MarkR is offline Brrrummm!
    Join Date
    Mar 2007
    Location
    High Peak, Derbyshire
    Posts
    317
    Thanks
    0
    Thanked 1 Time in 1 Post

    BMW G650GS Auxiliary Fuel Tank

    Auxiliary Fuel Tank – BMW G650GS 2011

    Introduction

    BMW have recently introduced the G650GS single cylinder enduro motorcycle (the German for motorcycle is ‘motorrad’ – hence BMW Motorrad). This motorcycle is a continuation of their very successful F650GS (single cylinder) which stopped production for Europe in 2007. Realising their mistake in not continuing production, the updated G650GS was born for 2011. This note focuses on the smaller fuel tank capacity of 14 litres total, of the G650GS as compared to the 17 litre capacity of the F650GS and my installation of a gravity fed 12 litre auxiliary fuel tank. This approach will also apply to any of the BMW motorcycles with an under seat fuel tank as the fuel access point to the main fuel tank will be common to these bikes.

    The low fuel warning light comes on with 4 litres left in the tank, which is after 155 miles at 70 mpg. When travelling in any remote areas of the British Isles, for me, this lower range is a nuisance as you are not guaranteed to easily find a petrol station now that many have shut in favour of the big super markets. The fitting of this auxiliary tank will increase the range to over 400 miles making searching for fuel a much lower priority.


    Equipment – ‘the bits and pieces’

    The tank is a USA Tour Tank (16” x 8”) which will hold 12 litres. It is fitted with a roll-over valve/tank vent which is ‘Td’ in with the existing tank roll-over valve/vent tube. The fuel flow from the auxiliary tank to the main tank is through a 90deg elbow, a fuel stop-tap, a fuel filter and a non-drip fuel connector making the trans-shipping of the fuel to a fuel can or to another motorcycle an easy and safe activity.

    The vent from the auxiliary tank is joined to the main tank pipe using a ‘Y’ connector which then vents to below the motorcycle in the usual way.

    The existing roll-over valve/tank vent is replaced with a purpose built and designed aluminium plate which holds a roll-over valve/tank vent and a fuel tank 90deg union sourced from the aero-industry. The photographs show all of the important aspects of this installation and my warning to everyone is that designing and installing fuel systems can be a dangerous activity and do not undertake the work unless you are capable of fuel systems pipe work and mechanical installations.

    My original F650GS was fitted with a Metal Mule rear rack to which I engineered the fitting of a Peli Case. I have re-installed this to the new G650GS. The tank is secured to the rear rack with two substantial mild steel ‘L’ brackets (bar 1” x ”) bolted to the rear rack. The standard Tour Tank securing loops bolt on to the ‘L’ brackets. There are sufficient clearances to allow the seat to be removed and replaced without any modifications to the motorcycle. Complete removal of the auxiliary tank will leave no trace of its installation.


    Preparation

    Before starting this installation, ensure that you have all of the components and do a ‘walk through’ of how you are going to tackle the whole job. Care needs to be taken when ensuring no fuel leaks, the routing of fuel lines to reduce any possible mechanical failure and most important, when removing the existing fuel roll-over valve/vent that nothing falls into the main tank especially any of the six securing Torx-bolts before the new plate is in position. Access to the rear seat-lock compartment and the removal of the seat also needs to be considered so the choice of a rear rack becomes a high priority.


    Watch your Threads and Pipe Diameters

    BSP is British Standard Pipe thread. (parallel thread and 57deg pitch)
    NPT is National Pipe Taper. (tapered thread and 60deg pitch)
    Inside pipe diameters can be 6mm (1/4inch) and/or 8mm (5/16inch).
    Outside pipe diameters (od) can be up to 14mm for an inside diameter (id) pipe of 8mm.
    ALWAYS use either PTFE tape or LocTite 567 on threads to prevent leaky joints.
    ALWAYS use hose clips or cable ties on barb and push-on fittings.
    4.55 Litres = I Imperial Gallon, 3.79 Litres = 1 US Gallon
    For this installation I used 6mm id hoses and fittings. The gravity flow for 6mm fittings is approx 45 seconds per litre.

    Photographs

    The photographs show the finished installation and a view of the tank access plate made from 1.6mm thick alloy sheet cut, drilled and filed, but no CNC this time.


    Some helpful links: (June 2011)

    Tour Tank, USA for tanks and the main accessory parts
    Demon Tweeks for fuel cut-off valve and hose fittings
    Your local plumbers merchant for PTFE tape
    Your local electronic store for cable ties and Halfords for Velcro ties


    Other suppliers of fuel system accessories:

    Goodridge Hose and Fittings – another source of fuel pipe fittings
    Earl's Performance Products – many fuel related parts


    Mark Raybould
    June 2011


    The new G650GS




    Aux Tank ready to GO!





    Peli case removed





    Pipe work





    The new access plate with rollover valve/vent and fuel access



    If you have any comments, please PM me.

    Modification No.1

    To prevent any air locks in the venting system, each tank will have its own separate vent tube. During fuel transfer with both filler caps closed, the main tank is expelling air whilst the aux tank is inhaling air. A stale mate could arise and prevent the flow of fuel.


    Modification No.2

    The tank's earthing lug has been connected to the chassis of the bike which will reduce any static buildup on the tank.


    Ride safely,
    Mark


    Last edited by MarkR; 16-06-11 at 09:36 AM. Reason: Modification to venting system and earthing of the tank
    "It's all very, very simple and easy to do!"

    TLD 2008 JOG-LE - 16h20m - F650GS
    G3XYS/NS1Q - IBA #40715/#53038

  2. Remove Advertisements
    XRV.org.uk
    Advertisements
     

  3. #2
    j's Avatar
    j
    j is offline SHW'MAE BUTT
    Join Date
    Apr 2006
    Location
    Rhondda boy living in Bridgend SouthWales
    Posts
    3,270
    Thanks
    7
    Thanked 120 Times in 115 Posts

    Re: BMW G650GS Auxiliary Fuel Tank

    Nice one mark, looks very neat . I agree with the problem looking for fuel in Northern Scotland is a bit of a worry sometimes.
    "Weisser Jagd Panzer" The white one



    BMW SAFE HOUSE AND GARAGE SOUTH WALES

  4. #3
    raymo's Avatar
    raymo is offline Senior Member
    Join Date
    Nov 2005
    Location
    aberdeenshire Scotland
    Posts
    3,692
    Thanks
    7
    Thanked 44 Times in 37 Posts

    Re: BMW G650GS Auxiliary Fuel Tank

    Hi Mark,

    seen these tanks before.. good idea, but its high up, any Handling issues?

    its a good mod . same issue in Scotland.. Even with a 25Lt RD04 Tank and 50mpg.. I still occasionally carry a 5 lt insurance tank in the far North of Scotland..

    Sorted now...... as I have fitted a 42lt Marathon Front Tank.. 400+ miles no longer a fuel junkie, always looking for the next fuel fix

    Neat Job
    XLV 750Rf RD01 1985 Simple and Sweet
    XL 600V R Transalp 1994 Stella Basher
    DR 600 Raider 1985 Knee Smasher
    XRV 750R RD03+ 1988 Frankathon spawn of the Transalp and RD01 , and a1992 750 Marathon kit
    XRV 650R RD03 1989
    The Longest Day Rider 6
    TLD 2008 John-O-Groats to Lands End 14h 50m 880 miles
    TLD 2009 5 capitals 23h 50m 700 miles
    TLD 2010 Run for the Sun 19h 30m.
    TLD 2011 Tower to Tower 17h 700m+ one channel Tunnel and arrived in time to watch the Eiffel Tower lights go on

  5. #4
    MarkR's Avatar
    MarkR is offline Brrrummm!
    Join Date
    Mar 2007
    Location
    High Peak, Derbyshire
    Posts
    317
    Thanks
    0
    Thanked 1 Time in 1 Post

    Re: BMW G650GS Auxiliary Fuel Tank

    Raymo - No real handling issues - 12 liters is 12 kgms and with all the other gear being carried it is just part of the general load. For general doodling around, the tank will be empty.

    J - I think it is about time that more of these aux fuel systems were generally made available. Years ago when working in the North and West of Scotland all fuel stations were shut by 5.00pm and closed on Sundays!

    Mark
    "It's all very, very simple and easy to do!"

    TLD 2008 JOG-LE - 16h20m - F650GS
    G3XYS/NS1Q - IBA #40715/#53038

  6. #5
    raymo's Avatar
    raymo is offline Senior Member
    Join Date
    Nov 2005
    Location
    aberdeenshire Scotland
    Posts
    3,692
    Thanks
    7
    Thanked 44 Times in 37 Posts

    Re: BMW G650GS Auxiliary Fuel Tank

    Quote Originally Posted by MarkR View Post
    Raymo - No real handling issues - 12 liters is 12 kgms and with all the other gear being carried it is just part of the general load. For general doodling around, the tank will be empty.

    J - I think it is about time that more of these aux fuel systems were generally made available. Years ago when working in the North and West of Scotland all fuel stations were shut by 5.00pm and closed on Sundays!

    Mark
    Did not think they would be an issue

    there is another angel to the fuel issue.. if you do find fuel its very pricey

    these tank are usually very shiny and on Harleys any reason for the wee coat ?
    XLV 750Rf RD01 1985 Simple and Sweet
    XL 600V R Transalp 1994 Stella Basher
    DR 600 Raider 1985 Knee Smasher
    XRV 750R RD03+ 1988 Frankathon spawn of the Transalp and RD01 , and a1992 750 Marathon kit
    XRV 650R RD03 1989
    The Longest Day Rider 6
    TLD 2008 John-O-Groats to Lands End 14h 50m 880 miles
    TLD 2009 5 capitals 23h 50m 700 miles
    TLD 2010 Run for the Sun 19h 30m.
    TLD 2011 Tower to Tower 17h 700m+ one channel Tunnel and arrived in time to watch the Eiffel Tower lights go on

  7. #6
    MarkR's Avatar
    MarkR is offline Brrrummm!
    Join Date
    Mar 2007
    Location
    High Peak, Derbyshire
    Posts
    317
    Thanks
    0
    Thanked 1 Time in 1 Post

    Re: BMW G650GS Auxiliary Fuel Tank

    The wee coat helps to disguise the tank and when I had it mounted on the R1200GS most on-lookers thought it was general luggage and not a fuel tank. But I suppose the wee coat could be a Tam o' Chanter or even a pair of bagpipes in disguise to us sassenacs! (spelt korectly?)
    "It's all very, very simple and easy to do!"

    TLD 2008 JOG-LE - 16h20m - F650GS
    G3XYS/NS1Q - IBA #40715/#53038

  8. #7
    raymo's Avatar
    raymo is offline Senior Member
    Join Date
    Nov 2005
    Location
    aberdeenshire Scotland
    Posts
    3,692
    Thanks
    7
    Thanked 44 Times in 37 Posts

    Re: BMW G650GS Auxiliary Fuel Tank

    Quote Originally Posted by MarkR View Post
    T But I suppose the wee coat could be a Tam o' Chanter or even a pair of bagpipes in disguise to us sassenacs! (spelt korectly?)
    no Idea. I'm from Yorkshire

    thought it was to keep it cool
    XLV 750Rf RD01 1985 Simple and Sweet
    XL 600V R Transalp 1994 Stella Basher
    DR 600 Raider 1985 Knee Smasher
    XRV 750R RD03+ 1988 Frankathon spawn of the Transalp and RD01 , and a1992 750 Marathon kit
    XRV 650R RD03 1989
    The Longest Day Rider 6
    TLD 2008 John-O-Groats to Lands End 14h 50m 880 miles
    TLD 2009 5 capitals 23h 50m 700 miles
    TLD 2010 Run for the Sun 19h 30m.
    TLD 2011 Tower to Tower 17h 700m+ one channel Tunnel and arrived in time to watch the Eiffel Tower lights go on

+ Reply to Thread

Similar Threads

  1. G650GS Switch Failures
    By MarkR in forum BMW
    Replies: 10
    Last Post: 28-07-11, 06:38 PM
  2. Borrowed a G650GS for a few days!
    By Metalmule in forum BMW
    Replies: 2
    Last Post: 18-04-11, 09:06 AM
  3. 2011 g650gs
    By fionaann in forum BMW
    Replies: 30
    Last Post: 01-04-11, 02:58 PM
  4. Replies: 0
    Last Post: 06-03-10, 12:50 AM
  5. fuel tank
    By GERASSIMOS13 in forum Africa Twin
    Replies: 9
    Last Post: 01-11-09, 03:59 AM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts