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Stage 1 Kit Fuel Mileage

Discussion in 'CVP Stage 1 Tuners Kit' started by ddices, May 26, 2010.

  1. ddices

    ddices New Member

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    Good morning, I am coming back now after you folks helped me get my bike running! 1996 Fatboy with moderate exhaust, K and N filter and Stage 1 Carb kit. RUNS strong but I am getting 25 MPG. Even with a windshield I would expect more than this. WONDERING if I am a tad too rich (and would that matter)?? Is this the outcome of the stage 1 carb kit? Planning on triple checking the timing (hard without a tachometer) and the plugs for sign of being rich. If I am then I plan on backing off on the air fuel mix. Would you agree and do you have any comments on the MPG before I do this..Thanks for your wisdom. Dave
  2. cowboy

    cowboy Moderator Staff Member

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    dave you might try that but alos try backing wrist some :D
  3. FLHTbiker

    FLHTbiker Moderator Staff Member

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    Check your plugs, that will till you if your running rich.
  4. kenfuzed

    kenfuzed Administrator Staff Member

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    All too often people use the larger size main jets, and while the bike may ride fine the larger jet dumps excess fuel above 3/4 throttle. Going down a size on the main jet won't effect your idle, off-idle, or midrange and will help avoid having to retune the mixture screw. Another common cause I've seen is over use of the enrichener.
  5. ddices

    ddices New Member

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    Jumped up to the 46 main jet as the 45 required about 4 turns out to eliminate some coughing. Worked with you folks to try the 46. I'm out 2 ish right now. Will check the plugs and if rich will back off the mix. If cannot get it right could always try the 45 again to your point. SO I am correct that the air fuel mix will impact overall fuel economy and not JUST the idle and off-idle performance.
  6. hotroadking

    hotroadking Super Moderator Staff Member

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    So will throttle position, the earlier post about watching your wrist applies

    Many times MPG goes down because the rider, finding more power, uses it more, and then bam instant drop in MPG...
  7. ddices

    ddices New Member

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    Of course you only have my word, but I assure you that that is not the case, not that we don't have our moments, before or after the kit install. Plugs were carboned around the rim. Backed off to 1.5 turns out which is just 1/4 turn more than stock (plus the 46 jet over the stock 42). We'll see what this brings. MPG is more if a sign to me of something not being right vs something to worry about from an expense standpoint. Don't ride enough to bother, but not pulling over every 100 miles will excellent. My continued thanks to all.
  8. hotroadking

    hotroadking Super Moderator Staff Member

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    Its normal to get it too rich, Fuel mileage is dictated by throttle position

    A needle that is too high (thin) will allow more fuel from the main jet, and if that
    jet is too large well, low MPG.

    The pilot or slow jet transitions to the needle, then the Main at WOT.

    Did you change the needle as well, If you are shimming the needle, remove the shim
    the Sportster needle is best for this carb, someone here will chime in with the PN...
  9. ddices

    ddices New Member

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    Used the new needle and tube from the stage 1 kit and I am using the 46 pilot jet and 180 main jet (not the 185 that also came with the kit). Plain old stage 1 kit upgrade/rebuild. Using the 46 as the 45 seemed to required too much turning out of the air/fuel mix (4 turns). I am at 1.5 turns out with the 46. At 1.25 the motor starts to "slow down" so I think that the 1.5 may be good. Have not yet taken her for a good run to test this but seemed ok on my short neighborhood test ride..Have a 1 month old baby so not as much time to play as is normally required for all this tuning. I'll check the plugs after a few miles and if still rich I may try the 45 pilot jet again. Seem logical?
  10. kenfuzed

    kenfuzed Administrator Staff Member

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    Yup, you are right on with your tuning approach.

    Have you checked to make sure your enrichener (choke) is closed and seating? Sometimes if the plastic nut is not screwed tight enough into the side of the carb it can allow the enrichener to always be slightly open which will drop your fuel mileage. This would also be evident by soot on the plugs and maybe even some soot buildup in the mufflers.

    Sometimes a drop in MPG can be attributed to non-fuel related conditions. For instance, a dragging brake pad, slipping clutch, or trans oil being too heavy or sludged can cause a change in mileage. Also as mentioned before things like throttle, high idle speed, or timing can impact mileage. It could also be a combination of many of these factors.
  11. ddices

    ddices New Member

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    Let's let the fun continue!! I will check the enricher; hadn't thought of that as it seems to close very distinctly. Tranny fluid is new and have checked the brakes, etc. Went through the bike when I purchased (first Harley and loving it..why did I wait so long?). We are still fine tuning the timing. We can see the marks ok but we're only guessing at the RPM we are timing her at..Don't have a tach..Any ideas on THAT one?
  12. tomcat

    tomcat New Member

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    Automotive Test Systems: Electronic Specialties Deluxe Multimeter Kit

    this is what I bought for adjusting the tach. Works great, and I can throw it in the saddle bags and randomly pull over and check the idle when I am trying to dial in the carb on a test run. the inductive pickup is directional sensitive, so if you don't get a reading, just turn it over as there is no direction arrow indication on the pickup itself.
  13. ddices

    ddices New Member

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    Borrowed an older tach/dwell tester from my neighbor. Gonna see if that works..BACK to the Fuel Economy..brought the air fuel mix back to 1.5 turns out and I am at 50 MPG..Still no burping, coughing, etc and bike runs great..Gonna double check the plugs this weekend..SO far so good!
  14. sarge7

    sarge7 New Member

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    Sounds like yer on the right track. At least ya ain't dealin with EFI. That is a can of worms I don't ever intend on opening!

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