Alternative fuel pumps for FI KTM990

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by cjracer, Jan 9, 2009.

  1. LukasM

    LukasM Long timer

    Joined:
    Nov 15, 2006
    Oddometer:
    5,445
    Location:
    On a RTW ride - next stop USA!
    Did you guys make any progress on this?

    I am looking for an external fuel pump that I can attach to a normal tank petcock for another project. Need about 45psi, so I would use an adjustable regulator as well. Ideally I would like to avoid a return line, can a setup like this be run in dead head configuration?
    #21
  2. Gimme 2

    Gimme 2 wheels , with nobs

    Joined:
    Mar 29, 2009
    Oddometer:
    2,176
    Location:
    still looking
    this'll be tops if you guy's get it sweet.
    my pump stuffed up at 1900 ks,
    The power decreased slowly while having to crank throttle more.

    then i turned off the ignition,

    then on again, must have re booted the ecu/ fi or something and she was good to go for another 20 mins until i had to do it all again.

    Did this all the way home 650 klms ,turn off then on whilst on the fly.

    got new pump installed when i got home and havent ridden bike a great deal cause in Western Aus, im in NSW.

    i hope this info can shed some light on the issue,

    Cheers
    #22
  3. azcagiva

    azcagiva new orange flavor

    Joined:
    Apr 23, 2007
    Oddometer:
    1,166
    Location:
    Camp Verde, AZ
    CA cycle works sells a 3.5 bar fuel pump $149.00.
    [​IMG]

    http://www.ca-cycleworks.com/shop/catalog/ducati/fuel.html#fuel%20tank

    From the looks of it you might be able to mount it in the same place as the 950 pump. It also looks like you can attach a hose to the pick up end allowing it to be mounted outside the tank.


    They also sell a vacuum mikuni pump for you carb guys that want an alternative to the beloved facet.
    -John
    #23
  4. azkiwi

    azkiwi message in a bottle

    Joined:
    Aug 11, 2004
    Oddometer:
    9,752
    Location:
    Upstate AZ
    Call me an optimist, but why do you think it necessary?

    There do not seem to have been many 990 pump failures (even fewer outside warranty). Every vehicle out there in the market has a fuel pump and very few of them die prematurely. Why should it be a continuing challenge for KTM?


    :dunno
    #24
  5. Autostream

    Autostream Long timer

    Joined:
    Aug 1, 2005
    Oddometer:
    5,833
    Location:
    Belgrave, Victoria, Australia
    is it the "internet magnification factor" ?

    How many actual failures have there been?
    #25
  6. tumbler45

    tumbler45 tumbler

    Joined:
    Jan 29, 2008
    Oddometer:
    100
    Location:
    Delaware
    Mine is failing at 30,000 miles. Same story as listed above, it started with the engine losing power and sometimes stalling when the fuel level was low, but only under hard braking or acceleration (I still havn't figured out why:huh ). Then one day I had just filled up and the bike felt like it wasn't running quite right. Did a few hard accerations and as soon as I put a hard load on the motor it just fell on its face. It idled fine, reved fine, just faltered under hard power. As I rode it got worse and worse. 45 minuites later I could hardly keep up with traffic.

    I wanted to confirm the fuel pump was the problem so I T'eed in a $20 NAPA gauge (similar to the KTM tool) before dropping $400 on a pump assembly. Put the bike back together and of course it ran perfectly. The problem with stalling under braking or acceleration also went away:huh .

    I ran 4000 miles without a problem (:huh ) removed the fuel gauge and still had no clue what caused the problem. 1000 miles later the problem resurfaced and worse than before. It was intermittent, but seemed to be affected by the heat of the fuel. When I let the bike cool or added fuel it would run much better.

    I have a fuel pump assembly on the way, I'll probalby pull the pump out of the old assembly and carry it as an emergency backup.
    #26
  7. azkiwi

    azkiwi message in a bottle

    Joined:
    Aug 11, 2004
    Oddometer:
    9,752
    Location:
    Upstate AZ
    What have you seen in the fuel filter?
    #27
  8. sp4ce

    sp4ce Orange Invader

    Joined:
    Oct 9, 2003
    Oddometer:
    431
    Location:
    State of Grace
    Yep. Check and replace the filters before you drop $$$ on the pump.

    I had all the symptoms reported in this thread - bogging at speed when throttle applied, intermittent poor running, turning the bike off and back on temporarily fixing the problem - and it was dirty filters. I replaced them and the bike was fine.

    I sure would be interested in an external pump solution. Not so much for the pump, but for the ability to run an external filter that doesn't cost $120.
    #28
  9. Autostream

    Autostream Long timer

    Joined:
    Aug 1, 2005
    Oddometer:
    5,833
    Location:
    Belgrave, Victoria, Australia
    I worked for Bosch as a technical sales rep for 7 years so have had a fair exposure to fuel pump issues.

    This is starting to sound like a pump cavitation issue.
    I have yet to open mine up and see how it is all set up, but from what I can tell, the pump sucks in fuel via a sock filter, pumps it through a small fine filter, builds up pressure in some internal pressure regulator with the excess bled back into the tank and the pressure fed out the single line.

    If I am correct in those assumptions then....
    • The same fuel will be circulated around the fuel pump in a very small volume as the tank empties out.
    • The tank is plastic so does not get rid of heat well.
    • The rather small main pressure filter will tend to block up quite easy, requiring more effort to pump fuel through, this will tend to increase the fuel pump power effort and hence heat generated.
    • Warm fuel being sucked through a partially pick up blocked filter will tend to cause the pump to cavitate, create vapor locks and generally conspire to stop the pump being able to create the pressure needed to run the bike. (EFI pumps are useless at sucking, great at blowing)
    • As the fuel temp increases the problem gets worse until engine stops altogether.
    For those that have had the problem, does the 'tone' of the pump sound at all like it is sucking air when things start to go kaput?

    Does this sound like it fits the symptoms?
    Add fuel or let it cool and all is fine.
    Cold ambient temps and all is fine.
    Hot ambient temps and it all happens faster.
    Traffic, where radiator heat is soaked into fuel tank, all is worse.
    Freeways, more airflow throught radiator so less absorbed into tank, runs better.


    Get the idea?
    #29
  10. tumbler45

    tumbler45 tumbler

    Joined:
    Jan 29, 2008
    Oddometer:
    100
    Location:
    Delaware
    First thing I did was pull off the filters and check them out. They were brown, but did not seem to be clogged. I could blow through them will no resistance (for whatever that is worth). I have also had the problem happen on a 50 degree day within 15 miles of filling up.

    Rather than spend $115 on a filter set and $60 on the orings (which is crazy!) I am going to buy a complete pump assembly and have a back up pump to carry.
    #30
  11. The Fist

    The Fist Knulp

    Joined:
    Mar 14, 2003
    Oddometer:
    3,607
    Location:
    Dolores, CO
    I just returned 4 days early from a solo trip into the deserts of Utah --

    I was about 300 miles from home and 20 miles into the Burr Trail when the bike (2008 990 Adventure) started starving for fuel. The bike would idle fine but when given throttle would chug along at about 2mph -- I was lucky to have been in a position to turn around and retreat to civilization, albeit very slowly with the bike dying every quarter mile.

    My guess is that the filters have become clogged but who knows, the pump might be failing as well. Had I been in a position to swap pumps trailside, I would saved myself ALOT of hassle. I didn't attempt to repair this issue at the gas station for fear that I would be only further from home once I started riding again and might be worse off with a false sense of confidence....

    Point is: 990's do have "fuel pump issues" and I am following this thread with great interest. Thanks to everyone involved.
    #31
  12. scorpion

    scorpion Two arm bandit

    Joined:
    Aug 10, 2004
    Oddometer:
    5,424
    Location:
    Planet Reno
    Do you still have the canister?
    Sounds like my problem before canisterectomy
    #32
  13. sp4ce

    sp4ce Orange Invader

    Joined:
    Oct 9, 2003
    Oddometer:
    431
    Location:
    State of Grace
    Fair enough, I can understand that.

    When my filters failed they were similar - brown, but otherwise not obviously clogged. I wouldn't have believed that was the problem if I hadn't blown the filter out with gasoline and compressed air and had it temporarily fix it.

    You can re-use the o-rings. Mine have been in and out a half dozen times and are still sealing fine. They are pretty hacked, but that is mostly because I am a ham-fisted wrench.

    Next time I have the pump out, I'll put in normal Viton o-rings instead of magic $60 KTM o-rings. If anyone has source and part number or dimensions for replacements, chime in. I know others here have done this.
    #33
  14. tumbler45

    tumbler45 tumbler

    Joined:
    Jan 29, 2008
    Oddometer:
    100
    Location:
    Delaware
    The last time I put my pump back in I cut one of the orings. I went to my local hydraulic shop and they gave me something that wasn't the exact size, but it has sealed perfectly. I can track down a p/n and post it.

    They were $1.25 for 2 sets of orings.

    I may try swapping just the filters first to see if my pump is in fact failing, but regardless I like the idea of having a spare pump to carry for the far from anywhere trips (Goose bay and beyond this summer!).
    #34
  15. Autostream

    Autostream Long timer

    Joined:
    Aug 1, 2005
    Oddometer:
    5,833
    Location:
    Belgrave, Victoria, Australia
    10 degrees celcius... hmm... there goes that theory...
    #35
  16. azkiwi

    azkiwi message in a bottle

    Joined:
    Aug 11, 2004
    Oddometer:
    9,752
    Location:
    Upstate AZ
    Just to keep this boiling;

    Point is: 990's may have "fuel filter issues".

    Maybe they just spec'd too fine of a filter? How bad does Super get? :scratch
    #36
  17. sp4ce

    sp4ce Orange Invader

    Joined:
    Oct 9, 2003
    Oddometer:
    431
    Location:
    State of Grace
    Depends...

    [​IMG]
    #37
  18. Gimme 2

    Gimme 2 wheels , with nobs

    Joined:
    Mar 29, 2009
    Oddometer:
    2,176
    Location:
    still looking
    Does this sound like it fits the symptoms?
    Add fuel or let it cool and all is fine.
    Cold ambient temps and all is fine.
    Hot ambient temps and it all happens faster.
    Traffic, where radiator heat is soaked into fuel tank, all is worse.
    Freeways, more airflow throught radiator so less absorbed into tank, runs better.


    Get the idea?[/quote]

    good assumptions , yes .......but mine began to fail with rain approaching brrrhh, and i was holding a constant speed for close to an hr of 140 ks per hr, yes real ks gps hooked up, to see the fuel consumption rate at this speed and for the fun factor, and also once the bike was switched off and then straight back on again it was fine for another 15 - 20 mins before slowly getting worse on a progressive downward scale,
    It was a long day Coolgardie to Fremantle so by the end i was doing it on the move , as soon as i felt the bike becoming slack in the power i would if i remember correct turn off the key so every thing was dead and then turn it back on then hit the starter with the clutch pulled in, down a gear to fourth or fivth and away she'd go again. 500 odd ks of this and i was home, not before stopping at the pub in freo:Dfor a well earned ale geez it was cold had to stop in Merrinden? for a poncho.

    I am hoping that there are'nt any spooks in the fuel pump maybe im just unlucky and i bet im not the only one hopeing that but , i rekon there is a suspect issue with them as a few people seem to have had similar issues. Time will tell .
    #38
  19. 911racer

    911racer dare to explore

    Joined:
    Feb 25, 2007
    Oddometer:
    471
    Location:
    Santa Cruz Mountains,CA
    I'm following this thread as I would like to have a out-board pump/filter for easy access and diagnostics on the side of the road.
    #39
  20. 911racer

    911racer dare to explore

    Joined:
    Feb 25, 2007
    Oddometer:
    471
    Location:
    Santa Cruz Mountains,CA
    hey any updates on this? :ear
    #40