Poor Road King MPG...Carb
Poor Road King MPG...Carb
I have a 2005 RK carb. Low miles around 10k. Got it from a one owner who did many nice mods. Some include a stage 1 intake big sucker and Bassani slip ons. He said he did dyno jet kit as well. It runs good. I just put new harley plugs in it and a full can of B12 fuel cleaner in the tank. Its actually running a tad lean as the carb farts a few times during a ride. The air / fuel screw plug has been removed so I will richen it up some till it wont backfire from the carb. Anyway im only getting 33 combined mpg. Seems I should be in the 40s right? This is Harley # 6 for me but my first carb and was really not wanting a carbed bike but the price was right. I also always run 91 octane.
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Joined: Sep 2010
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From: Phoenix '53, '88, '09 Big Twins
depending on cams and heads, you may be fine with 89 octane.
the CV carb is easily tuned and the nightrider.com site has good tuning and modding info...check the biketech section, then read up on tuning and modding teh carb.
completely possible that the dynojet kit is junk ( that is my opinion) if they replaced the slide with a piece of plastic.
the classic mod is drill the stock slide bleed hole to .125", chamfer the edge, eplace needle with N65 sporty needle, and rejet...maybe 45 and 175 for your bike.
with careful tuning and record keeping, my 1995 80" FLHTC would return 45 MPG at a steady 65 MPH. crane hi4 single fire.
89 octane, 10% corn welfare.
I used mpg, *** dyno and an o2 sensor to do my tuning...I was tuning for best range.
sneezing through the intake can be lean...and that could be due to a clogged jet...but don;t try tuning anything until you are running pump gas- no "magic additives".
sneezing can also be too advanced spark timing or a valvetrain problem ( less likely).
if you are using the screw for the idle air jet- use a little locktite- I have seen then vibrate out and fall between the lifter blocks if lucky.
there is also an aftermarket replacement which uses a knurled know for easy adjustment.
I love the CV carb and have one on my 88 FXR- the 95 FLHTC is gone.
pushing through the air is tough...same bike would drop to about 38 MPG at 75 MPH...and 32 MPG at 85 MPH
I often run I-10 between PHX and LA- it became apparent that running at the speed limit ( 75 in AZ and 70 in CA) would allow me to start on a full tank, stop once for fuel and make the trip in about 6 hours.
running faster like 80/85 would require an additional gas stop and get me there in about...6 hours.
No time saved.
Running at a speed closer to other traffic also reduced passing hazard
Mike
the CV carb is easily tuned and the nightrider.com site has good tuning and modding info...check the biketech section, then read up on tuning and modding teh carb.
completely possible that the dynojet kit is junk ( that is my opinion) if they replaced the slide with a piece of plastic.
the classic mod is drill the stock slide bleed hole to .125", chamfer the edge, eplace needle with N65 sporty needle, and rejet...maybe 45 and 175 for your bike.
with careful tuning and record keeping, my 1995 80" FLHTC would return 45 MPG at a steady 65 MPH. crane hi4 single fire.
89 octane, 10% corn welfare.
I used mpg, *** dyno and an o2 sensor to do my tuning...I was tuning for best range.
sneezing through the intake can be lean...and that could be due to a clogged jet...but don;t try tuning anything until you are running pump gas- no "magic additives".
sneezing can also be too advanced spark timing or a valvetrain problem ( less likely).
if you are using the screw for the idle air jet- use a little locktite- I have seen then vibrate out and fall between the lifter blocks if lucky.
there is also an aftermarket replacement which uses a knurled know for easy adjustment.
I love the CV carb and have one on my 88 FXR- the 95 FLHTC is gone.
pushing through the air is tough...same bike would drop to about 38 MPG at 75 MPH...and 32 MPG at 85 MPH
I often run I-10 between PHX and LA- it became apparent that running at the speed limit ( 75 in AZ and 70 in CA) would allow me to start on a full tank, stop once for fuel and make the trip in about 6 hours.
running faster like 80/85 would require an additional gas stop and get me there in about...6 hours.
No time saved.
Running at a speed closer to other traffic also reduced passing hazard
Mike
Last edited by mkguitar; May 6, 2015 at 11:16 AM.
Banned
Joined: Mar 2012
Posts: 11,232
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From: Socialist Republic of the USA
depending on cams and heads, you may be fine with 89 octane.
the CV carb is easily tuned and the nightrider.com site has good tuning and modding info...check the biketech section, then read up on tuning and modding teh carb.
completely possible that the dynojet kit is junk ( that is my opinion) if they replaced the slide with a piece of plastic.
the classic mod is drill the stock slide bleed hole to .125", chamfer the edge, eplace needle with N65 sporty needle, and rejet...maybe 45 and 175 for your bike.
with careful tuning and record keeping, my 1995 80" FLHTC would return 45 MPG at a steady 65 MPH. crane hi4 single fire.
89 octane, 10% corn welfare.
I used mpg, *** dyno and an o2 sensor to do my tuning...I was tuning for best range.
sneezing through the intake can be lean...and that could be due to a clogged jet...but don;t try tuning anything until you are running pump gas- no "magic additives".
sneezing can also be too advanced spark timing or a valvetrain problem ( less likely).
if you are using the screw for the idle air jet- use a little locktite- I have seen then vibrate out and fall between the lifter blocks if lucky.
there is also an aftermarket replacement which uses a knurled know for easy adjustment.
I love the CV carb and have one on my 88 FXR- the 95 FLHTC is gone.
pushing through the air is tough...same bike would drop to about 38 MPG at 75 MPH...and 32 MPG at 85 MPH
Mike
the CV carb is easily tuned and the nightrider.com site has good tuning and modding info...check the biketech section, then read up on tuning and modding teh carb.
completely possible that the dynojet kit is junk ( that is my opinion) if they replaced the slide with a piece of plastic.
the classic mod is drill the stock slide bleed hole to .125", chamfer the edge, eplace needle with N65 sporty needle, and rejet...maybe 45 and 175 for your bike.
with careful tuning and record keeping, my 1995 80" FLHTC would return 45 MPG at a steady 65 MPH. crane hi4 single fire.
89 octane, 10% corn welfare.
I used mpg, *** dyno and an o2 sensor to do my tuning...I was tuning for best range.
sneezing through the intake can be lean...and that could be due to a clogged jet...but don;t try tuning anything until you are running pump gas- no "magic additives".
sneezing can also be too advanced spark timing or a valvetrain problem ( less likely).
if you are using the screw for the idle air jet- use a little locktite- I have seen then vibrate out and fall between the lifter blocks if lucky.
there is also an aftermarket replacement which uses a knurled know for easy adjustment.
I love the CV carb and have one on my 88 FXR- the 95 FLHTC is gone.
pushing through the air is tough...same bike would drop to about 38 MPG at 75 MPH...and 32 MPG at 85 MPH
Mike
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Joined: Apr 2012
Posts: 9,982
Likes: 5,220
From: Michigan
I have a '98 Heritage Springer (EVO) with a carb and I put a Dyno-Jet kit in it several years ago mainly because I put straight Samson exhausts on it and I didn't want to run it too lean.
My mileage took a real "hit".
I rarely ride the bike these days but I'd guess that it gets somewhere in the high 30's MPG's.
My mileage took a real "hit".
I rarely ride the bike these days but I'd guess that it gets somewhere in the high 30's MPG's.
Cruiser
Joined: Sep 2006
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From:
CCS FXD
If a comparison helps, you are about 5 mpg. behind the combined 38 mpg. on my 95" 2001 RK carb. Three friends with 96" 2007 injected RK's usually get 2 mpg. more on long road trips. I am running a snappy 3.37 final gear ratio and suspect that the minor mileage differences are due to their much taller gearing.
If a comparison helps, you are about 5 mpg. behind the combined 38 mpg. on my 95" 2001 RK carb. Three friends with 96" 2007 injected RK's usually get 2 mpg. more on long road trips. I am running a snappy 3.37 final gear ratio and suspect that the minor mileage differences are due to their much taller gearing.
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Joined: Mar 2008
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From: Everywhere
My 99 w/carb would get close to 50mpg when riding lazy country roads all day. Stage II with bigger Mikuni carb. It dropped into the 30s running 75mph in 5th gear. Before the carb swap, low 40s was norm when running 75 all day.
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Joined: Jan 2007
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From: Twin Cities, MN
My '99 RK is an 88" stage two with Andrews 21 cams. My CV carb has run flawlessly for over 75k miles. I have the "classic" carb mod and very rarely get below 40 mpg. My typical mileage is 42-44. I would agree the dyno jet kit may be the problem. Have read for years it was not very good.
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From: Here and there
CCS FXD
If a comparison helps, you are about 5 mpg. behind the combined 38 mpg. on my 95" 2001 RK carb. Three friends with 96" 2007 injected RK's usually get 2 mpg. more on long road trips. I am running a snappy 3.37 final gear ratio and suspect that the minor mileage differences are due to their much taller gearing.
If a comparison helps, you are about 5 mpg. behind the combined 38 mpg. on my 95" 2001 RK carb. Three friends with 96" 2007 injected RK's usually get 2 mpg. more on long road trips. I am running a snappy 3.37 final gear ratio and suspect that the minor mileage differences are due to their much taller gearing.
That's usually what I see - about 38 mpg combined. I also have a 95" build with a CV carb, and I tend to be a little heavy on the throttle (usually cruise at 75-80 on the freeway).
Before I got the engine work done, I was seeing 40-42 mpg. Whatever. It's not a Prius, so I don't really care that much as long as the bike is running strong.
