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Author Topic: F1 fuel range reserve fixed!  (Read 2306 times)

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Offline Don R

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F1 fuel range reserve fixed!
« on: May 11, 2011, 10:22:10 PM »
My F1 is getting about 95 miles on a tank before reserve. It figures about 39 to 45  mpg depending on how hard I'm riding but the range seems a lot less than a K before reserve. About 2.5 gallons. is there more reserve on an F or smaller tank?
« Last Edit: May 13, 2011, 08:15:05 PM by Don R »
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Offline cookindaddy

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Re: F1 fuel range
« Reply #1 on: May 12, 2011, 08:12:59 AM »
Are you losing gas out the carb overflow tubes?

I have a 750K8 and last calculated 55 mpg and was pleasantly surprised. I think that the tank is the same size.
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Offline BeSeeingYou

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Re: F1 fuel range
« Reply #2 on: May 12, 2011, 08:47:59 AM »
The F has a bit more fuel capacity. 4.8 vs. 4.5 gallons than the K.  Your results may vary depending on vintage. :)  I think it just hits reserve sooner but because of gearing differences the K may get a bit better mileage.  I seem to hit it between 100-120 miles.  Ultimate range seems to be 200-210.  Yeah, I ran it dry once. ;D
« Last Edit: May 12, 2011, 08:50:55 AM by srust58 »
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Offline Steve F

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Re: F1 fuel range
« Reply #3 on: May 12, 2011, 09:44:02 AM »
On my F1's I would make it a rule to fill up at 100 miles so I won't need the reserve.  I probably can go 120 or so before hitting the reserve.
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Offline Don R

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Re: F1 fuel range
« Reply #4 on: May 12, 2011, 04:37:52 PM »
I've been getting 95 miles but coming back from Topeka I got caught in the boonies and it didn't want to run on reserve, I choked it, fiddled with the fuel selector and it took off. I got gas at 112. Then 300 miles later it went on reserve at 93 started to run poorly and died at 103. We were going down a long grade. I'm sure there was gas left in it. I had tested the petcock last week and again today. Everything looks good. I ordered the screen assy that goes inside the tank at the petcock because the screen was missing. We filled the tank, ran it into a can then tested reserve and it worked OK. Not really sure what has been happening yet.
« Last Edit: May 12, 2011, 04:40:51 PM by Don R »
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: F1 fuel range
« Reply #5 on: May 12, 2011, 05:38:27 PM »
Don,

I'd think you would do better than that. I'd also think you could get 175 miles on a tank at 40mpg. I'm thinking again that my reserve starts around 125 miles. 4.7 gallon tank according to one of my manuals with a reserve of 1.3 gallons. If you need a measurement of the tube height to compare with yours I can pull my relatively new petcock. Hey, at least you're not having to gas at 70 miles like the 650 I was riding.
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Offline MasterChief750

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Re: F1 fuel range
« Reply #6 on: May 12, 2011, 05:45:39 PM »
im in the 120 mile ish range before reserve on my k
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Offline Don R

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Re: F1 fuel range
« Reply #7 on: May 12, 2011, 06:53:10 PM »
Right, my K3 would always go 120-125 no worries that's why I asked. I tested the petcock again and it worked fine, I'll ride 50 miles in the afternoon tomorrow. At least I got the clutch working well. Going to test it again now.
 Jerry, not sure how you made it. Some places we rode it seemed like there weren't very many stations.
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Offline Don R

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Re: F1 fuel range, Reserve fixed!
« Reply #8 on: May 13, 2011, 08:14:40 PM »
I fixed the petcock there is a small D shaped gasket under the fuel pick-up riser the gasket was twisted and made a small flap that almost covered the reserve fuel outlet. My local shop was able to get the kit with the riser, screen, seal, etc.
« Last Edit: May 13, 2011, 08:16:28 PM by Don R »
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 You don't need a weatherman to know which way the wind blows.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: F1 fuel range reserve fixed!
« Reply #9 on: May 13, 2011, 09:46:40 PM »
Great news! And at least we can still get a few parts for these F's.
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As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)
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