mpg conversion is this right?

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May 7, 2012 | 01:47 PM

#11

RidemyEVO

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From: Northern Ontario

Quote:

Originally Posted by monkeyboy22

It also means your odometer is off and is also throwing off your MPG.

What was your MPG before changing the carb and or cam? Did you change both at the same time?

Mpg was about the same. I did take the speedo being off and accounted for it. I've had the cam for a while now.
I do notice the enrichener has a bit of sponginess to it in the closed position,like with it closed I can push it another 1/8 of an inch.

May 7, 2012 | 04:35 PM

#12

FXD_One

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Joined: Sep 2011

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From: Ontario, Canada

Quote:

Originally Posted by RidemyEVO

Do you have a stock cam?

I have an Andrews EV27 cam and a Killer carb, when the weather improves I'll do the calculation as well and post the results. Been riding the bike since Saturday ( just got it from the shop ) and I've been having so much fun I didn't even think about it. lol

May 7, 2012 | 05:09 PM

#13

PanHeadRich

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From: Big Bear City, CA

Quote:

Originally Posted by RidemyEVO

Do you have a stock cam?

Yes, my motor is stock. Other than breather & pipes, it's all stock.

Quote:

Originally Posted by RidemyEVO

Well now that the conversion part is figured out ( thankyou Internet) I need some help increasing gas millage. I emailed Dale the builder of the Killer Carbs and he said "As far as gas mileage goes I have hundreds of customers we flh's and the stock motors with a good exhaust and air cleaner are getting 48 mpg on the road but as soon as you put in a cam the mileage will drop by 15 to 20 percent depending on the cam.

15% to 20% seems to be a bit much from a cam change. Regardless, for some reason you're burning about 27% more fuel than me. I would expect that from a 124" S&S, but it seems a bit much for your bike.

I ordered one of Dale's carbs a week ago. Hopefully I won't see a drastic drop in MPG. All other threads I've read that mentioned MPG after his carb install have been good.

May 7, 2012 | 05:35 PM

#14

RidemyEVO

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From: Northern Ontario

I'm going to check for intake leak and also give some thought to the enrichener, would that enrichener needing the extra push to close be a culprit?
You are correct on the killer carbs , I've heard nothing but increases in mpg but hard to find flht's with the upgrades.

May 7, 2012 | 06:04 PM

#15

RidemyEVO

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From: Northern Ontario

For those in the know will a too large pilot jet eat up the mpg?

May 7, 2012 | 07:03 PM

#16

95yj

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Joined: Mar 2008

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From: Aruba

Quote:

Originally Posted by RidemyEVO

For those in the know will a too large pilot jet eat up the mpg?

Yes, increasing pilot jet size will make the bike run richer and lower your fuel economy. Each additional jet size will be noticeable and two or three jet sizes could be better than five mpg.

Quote:

Originally Posted by RidemyEVO

would that enrichener needing the extra push to close be a culprit?

Yes, if the enrichener is not in all the way, you're adding more fuel to the mix. (Unlike an automobile, the enrichener is not a choke which "chokes" off air, it is actually an enrichener which will add fuel to the fuel mixture.) This would be very similar to running a bigger pilot jet.

May 7, 2012 | 09:22 PM

#17

RidemyEVO

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From: Northern Ontario

Thanks YJ that gives me a place to begin after I check the intake for leaks.
By the way do you really live on the breezie island of Aruba?

Last edited by RidemyEVO; May 7, 2012 at 09:37 PM.

May 7, 2012 | 10:08 PM

#18

FXD_One

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From: Ontario, Canada

Quote:

Originally Posted by 95yj

Yes, increasing pilot jet size will make the bike run richer and lower your fuel economy. Each additional jet size will be noticeable and two or three jet sizes could be better than five mpg.

Yes, if the enrichener is not in all the way, you're adding more fuel to the mix. (Unlike an automobile, the enrichener is not a choke which "chokes" off air, it is actually an enrichener which will add fuel to the fuel mixture.) This would be very similar to running a bigger pilot jet.

The biggest rich condition on Dale's modified carbs is when the accelerator pump kicks in. Goes way rich through the 1700 rpm range to 2800 or more and drops from 13 to 1 ( optimal ) to about 11.75 to 1 ( rich ).

On the dyno test sheet on another of my posts, incomparison to the latest dyno sheet I have ( will post soon ) shows that dispite Dales heavy jetting the carb can easily be leaned out or enriched using the mixture screw.