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Old 03-06-2008, 08:56 PM   #1
Mr Lefty
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Default Carbs on long trips

I've been think'n of doing some long runs when I finally get to CO... and most are gonna take me through mountain passes and down into vallys... I'll be living at the feet of the Rockies... and I wonder...

What kinda issues am I gonna run into (if any) with power loss with a carbed bike? I know with EFI it auto adjusts and obviously I'm not gonna stop and adjust my carbs for every elevation change

will it even be that big a deal? just kinda wondering what to expect.
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Old 03-06-2008, 09:00 PM   #2
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I'd say minimal, but OTB and No Worries would know more. The higher compression a bike makes should offset any loss you'd see in a cage... Diesel semis with superchargers don't see any loss that I know of.
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Old 03-06-2008, 09:01 PM   #3
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it shouldnt be to noticable if you're just cruising.

when i was down in tenn last summer, the elevation might have fuckered up my bike a bit tho. for some reason after goin up the skyway, and back down, my bike just quit on me. Engine would NOT run. i think it was mostly user error, but just in case make sure you've got a way to reach someone or a way to get your ass off the mountain if worst comes to worse.
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Old 03-06-2008, 09:02 PM   #4
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Originally Posted by NONE_too_SOFT View Post
it shouldnt be to noticable if you're just cruising.

when i was down in tenn last summer, the elevation might have fuckered up my bike a bit tho. for some reason after goin up the skyway, and back down, my bike just quit on me. Engine would NOT run. i think it was mostly user error, but just in case make sure you've got a way to reach someone or a way to get your ass off the mountain if worst comes to worse.
so what ened up being the issue?
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Old 03-06-2008, 09:15 PM   #5
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still dont know to this day.

I think i was messing with the engine idle too much, that was part of the problem. but at the time it was the ONLY way i could get my engine to run for more than 2 seconds (was to raise the idle speed)

My guess was the fuel pump had some debris or something that got worked out.

For that reason, i plan on replacing it before i head to deals gap this year.
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Old 03-06-2008, 09:20 PM   #6
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still dont know to this day.

I think i was messing with the engine idle too much, that was part of the problem. but at the time it was the ONLY way i could get my engine to run for more than 2 seconds (was to raise the idle speed)

My guess was the fuel pump had some debris or something that got worked out.

For that reason, i plan on replacing it before i head to deals gap this year.
yeah fuel filter is something I'm gonna change before I leave for Indy


oh... and SeaFoam is great stuff for cleaning your carbs... you can pour it in the carb (I did on my truck) or put it in the gas... you can even spry it (comes in a spray and normal liquid form) in the intake to help clean the intake track...
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Old 03-06-2008, 09:30 PM   #7
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Quote:
Originally Posted by Ebbs15 View Post
I've been think'n of doing some long runs when I finally get to CO... and most are gonna take me through mountain passes and down into vallys... I'll be living at the feet of the Rockies... and I wonder...

What kinda issues am I gonna run into (if any) with power loss with a carbed bike? I know with EFI it auto adjusts and obviously I'm not gonna stop and adjust my carbs for every elevation change

will it even be that big a deal? just kinda wondering what to expect.
You will prolly not notice much, as long as your bike is in good running order to begin with. You can figure out the appoximate horsepower loss with this calculator. http://www.webcalc.net/calc/0757.php Less airflow means less mixture, means less power.

That should be the only really noticable result.
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Old 03-06-2008, 09:31 PM   #8
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Originally Posted by OTB View Post
You will prolly not notice much, as long as your bike is in good running order to begin with. You can figure out the appoximate horsepower loss with this calculator. http://www.webcalc.net/calc/0757.php Less airflow means less mixture, means less power.

That should be the only really noticable result.
ok... I was figure'n the only thing I'd loose was a bit of HP just wasn't sure how much... and if it'd be that big a deal...

Thanks!
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Old 03-06-2008, 09:33 PM   #9
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uh... when I use that link and set it to


Elevation 14000
BHP at sea level 100

Brake Horsepower loss : 420


shit!

even setting at 1500 feet it says I loose 45hp...

somethings wrong
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Old 03-06-2008, 10:37 PM   #10
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I have a 96 CBR600 F3 with 32,000 miles on it. I took a 800 mile weekend trip a month ago(By myself and 100s of miles from anyone I knew). Which I went from Atlanta, GA to Augusta Georgia in which you go down in elevation. Then I rode from Augusta to Deal's Gap and ran the dragon in the same day. Then the Cherohola (which does reach over a mile at one point) the next day and back to Atlanta including riding in rain the entire way back.

Infact here it the route from Augusta to Deal's Gap that I took...
http://maps.google.com/maps?f=d&hl=e...108643&t=p&z=8

I didn't notice any problems with the bike nor a performance loss(even with my carbs tuned for Full exhaust and having stock exhaust on it). I felt like the exhaust got quieter when I went in up in elevation fast but my friends with their EFI bikes(Not at the gap but another mountain) noticed teh same thing with theirs.

Of course comparing my mountains to your mountains would be like comparing Paris Hilton's breasts to Dolly Parton's breasts. You just can't.

I think your bike would be fine but maybe do some test runs up a very tall mountain to see how it really feels. Also my buddy's GF just got a brand new ZZR600 and those things are freaking sweet. Even though they are carbed.
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