1. After 20+ years it's time to pass the torch. If you are interested in acquiring this forum please contact support@cv-performance.com for details. Any spam will be reported and blocked.
  2. Welcome to Bike Talk, a forum for all bikers and motorcycle enthusiasts. If you are new to Bike Talk, be sure to register for free and join the conversation.

    There's always someone around willing to help out with questions or give a friendly wave back. All Harley and metric riders are welcome.
Bike Talk Motorcycle Forum is For Sale Welcome to Bike Talk

O3 Twinkie stumble at 2,800 rpm mod load.

Discussion in 'Motorcycle Tech Talk' started by rstar96, Dec 10, 2006.

  1. rstar96

    rstar96 New Member

    Joined:
    Dec 10, 2006
    Messages:
    3
    Likes Received:
    0
    Location:
    Central Florida
    My 03 RK 1550 Stage I with basic download, V&H dresser duals, touring mufflers and a TLE hack on the side and 30,000 miles runs strongly and accelerates nicely but at light to moderate load an irritating stumble and the occ spit out the EFI is really a bummer. I have jsut pulled/replaced the fuel filter and examined all the internal tank and external line components for leaks or seal problams and have found nothing, while doing this, I have changed what looked to be fine HD plugs and am replacing the IGN wires with SE 8mm silicone type.

    What to do now? No codes, by the way. :puke:

    Warren
    rstar96, Dec 10, 2006
    #1
  3. Sleepy

    Sleepy Well-Known Member

    Joined:
    Apr 6, 2004
    Messages:
    1,665
    Likes Received:
    73
    I was hoping someone with more knowledge would weigh in here. I think Harley's download is pretty generic and may not work with all pipe/air cleaner combos. to fine tune things some folks get the Screaming Eagle Race Tuner. Sounds like something isn't quite right in the mapping..assuming the hardware is OK. are you the Warren from Xroads and had the Urals?..sorry I couldn't be of more help.
    Sleepy, Dec 12, 2006
    #2
  4. mwelych

    mwelych Active Member

    Joined:
    Apr 19, 2006
    Messages:
    1,211
    Likes Received:
    0
    Location:
    Charlotte, NC
    Noticed this is your first post... Welcome... Lotsa good fo;ks here. Enjoy...:)
    mwelych, Dec 12, 2006
    #3
  5. kenfuzed

    kenfuzed Administrator Staff Member

    Joined:
    Jan 1, 2005
    Messages:
    10,513
    Likes Received:
    140
    Location:
    Las Vegas NV
    Has the problem only just started happening or has it been like this since your last upgrade (exhaust, BB, etc)? If the problem has persisted since then I'd say you need to get her mapped. Hard to go wrong with either the SE tuner or Power Commander III.
    kenfuzed, Dec 12, 2006
    #4
  6. rstar96

    rstar96 New Member

    Joined:
    Dec 10, 2006
    Messages:
    3
    Likes Received:
    0
    Location:
    Central Florida
    Yep, that's me, with Urals as well!

    A VERY, VERY minor low load stumble has been there for a good while before the hack was put on, not aggravating without the sidecar. To get more power I had the 1550 Stage I kit installed, NICE improvement in power. The stumble is more pronounced now and seems to be getting worse by the day with some spitting out the FI, I have about 2,000 miles with the engine mods in place. I am going to run it in a few days (medically down for a couple days, argh) with the new internal tank tubing and fuel filter in place, MAYBE I was getting an air leak in them, not likely as I see no defects.

    Boy, is that a PIA job getting the fuel pump assembly out of the tank!

    Warren
    Last edited: Dec 12, 2006
    rstar96, Dec 12, 2006
    #5
  7. kenfuzed

    kenfuzed Administrator Staff Member

    Joined:
    Jan 1, 2005
    Messages:
    10,513
    Likes Received:
    140
    Location:
    Las Vegas NV
    Really sounds like you need to update that map if its the one used before the BB build. Keep us up to date.
    kenfuzed, Dec 12, 2006
    #6
  8. rstar96

    rstar96 New Member

    Joined:
    Dec 10, 2006
    Messages:
    3
    Likes Received:
    0
    Location:
    Central Florida
    Unfortunately, not that easy, no downloads at all before the 95" H-D upgrade kit which requires the enhanced Stage I upgrade. Playing by the written rules and installing the download with the 95" kit (K&N style air cleaner, pistons, jugs, gaskets, valve seals, download).

    Before the 95" kit, no work on the engine other than V&H Dresser Duals headers with EPA legal mufflers, oem inlet and air cleaners, with base timing and controls.
    rstar96, Dec 13, 2006
    #7
  9. Sleepy

    Sleepy Well-Known Member

    Joined:
    Apr 6, 2004
    Messages:
    1,665
    Likes Received:
    73
    I think Harley's downloads are set up for their equipment..pipes/air cleaner/ big bore kit. your pipes may pull enough air thru the motor at a light load throttle setting to give you a lean stumble..[just fishing here] you may want to get a SERT or something like it to get your motor dialed in. i'm running a 95 inch stage one on the Electra Glide..with stock mufflers yet. Not great power but the bike runs crisp..even pulling the trailer. Fuel Injection is great when it's on but can be a bit of a bear when it's nor quite there..[based on my Ducati experience]....anyway, keep those Urals happy and it's nice seeing some old familiar folk coming back..been a while
    Sleepy, Dec 13, 2006
    #8
  10. hotroadking

    hotroadking Super Moderator Staff Member

    Joined:
    Jun 16, 2004
    Messages:
    13,682
    Likes Received:
    584
    Location:
    Mouseville USA
    Thinking back when did the stumble start, was it that way before all the parts upgrades.

    You could go and toss new sensors at it, engine temp etc but you could also get a powercommander on it, most of the time getting the tps set right and mapping done on a dyno is the best solution.

    Getting it on a dyno and a scan tool on the bike would allow the reading of the range on the sensors to see if any one is out.

    One thing you could do is test for an intake leak by using wd40 spray some around the intake seals to see if idle changes indicating a leak.
    hotroadking, Dec 13, 2006
    #9

Share This Page

XenPorta © Jason Axelrod from 8WAYRUN.COM