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Offline DammitDan

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Dyno testing?
« on: July 26, 2006, 04:55:36 AM »
I dunno if maybe this has been covered, but I didn't see anything in the FAQ about it.

I know the purpose of a dyno is to put the bike under load in a controlled measureable situation...  Therefore you can read horsepower output at different RPMs and speeds.  However, how can a dyno test help you with your jetting/mixture problems?  I've never had a dyno done, so what's the procedure for it?
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Offline MRieck

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Re: Dyno testing?
« Reply #1 on: July 26, 2006, 05:02:53 AM »
The graph will show your air/fuel ratio throughout the run. You can see if you are lean or rich. It is real helpful.
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Offline Lumbee

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Re: Dyno testing?
« Reply #2 on: July 26, 2006, 08:21:56 AM »
...yea, I've always wondered that too...how is the air/fuel mixture measured.  Is here a sensor thats placed in/at the tail pipe?
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Offline MRieck

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Re: Dyno testing?
« Reply #3 on: July 26, 2006, 12:10:58 PM »
Quote from: The great "Lumbee" on July 26, 2006, 08:21:56 AM
Is there a sensor thats placed in/at the tail pipe?
Correct. You shoot for 13 to 1 ratio.
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Offline Lumbee

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Re: Dyno testing?
« Reply #4 on: July 26, 2006, 02:36:53 PM »
13 parts carbon to one oxygen?

or 13 parts fuel to one part oxygen?
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eldar

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Re: Dyno testing?
« Reply #5 on: July 26, 2006, 09:27:43 PM »
13 parts air to 1 part fuel is supposed to be the ideal mix. I think.
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Offline cben750f0

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Re: Dyno testing?
« Reply #6 on: July 27, 2006, 04:41:41 AM »
here is a copy of my dyno chart, there is a huge lean spot, and was told by the dyno tech, that usually its because the CB's dont have accelerator pumps, and that by lifting the needles a clip would probably fix it, but it is around the 13:1..... hope this helps... peace
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Offline Lumbee

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Re: Dyno testing?
« Reply #7 on: July 27, 2006, 05:50:24 AM »
Quote
the CB's dont have accelerator pumps

 :o  Eldar, are you going to let him get away with that!!!
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Offline cben750f0

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Re: Dyno testing?
« Reply #8 on: July 27, 2006, 06:07:07 AM »
OK!!!!! jeeeeeeez, pre 78 CB's dont have accellerator pumps!!!!!!....picky picky!!!!...peace ;D
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you are never to old, to act like a kid... be safe
funny thing,chasing someone down hill on a bike 30 years older than theirs..
he said \\\\\\\'it was like watching a 250kg unguided weapon getting stuck up you bum\\\\\\\ http://www.bikepics.com/members/trixtrem/

Offline MRieck

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Re: Dyno testing?
« Reply #9 on: July 27, 2006, 06:10:36 AM »
Quote from: cben750f1 on July 27, 2006, 06:07:07 AM
OK!!!!! jeeeeeeez, pre 78 CB's dont have accellerator pumps!!!!!!....picky picky!!!!...peace ;D
Now you've gone and done it! :D
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eldar

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Re: Dyno testing?
« Reply #10 on: July 27, 2006, 06:10:44 AM »
See he corrected his mistake! He wasnt actually degrading anything ;D
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Offline Lumbee

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Re: Dyno testing?
« Reply #11 on: July 27, 2006, 06:30:29 AM »
Quote
pre 78 CB's dont have accellerator pumps!!!!!!

...you mean pre 77's   ::)
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Offline cben750f0

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Re: Dyno testing?
« Reply #12 on: July 27, 2006, 04:35:05 PM »
no b/c i have a 77 F1, that dont have pumps.... and i am the second owner, and it was like that when it was impoted to australia........but noone can tell my why...peace
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funny thing,chasing someone down hill on a bike 30 years older than theirs..
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Dyno testing?
« Reply #13 on: July 27, 2006, 05:05:05 PM »
Ben,

What's the engine serial number ??? In the states that bike was a 1976 F1 the way it looks (which is nice by the way). The dyno chart did you well. Thats really an invaluable tool ! Have you tried raising the needle yet?

Jerry
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Offline cben750f0

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Re: Dyno testing?
« Reply #14 on: July 27, 2006, 05:24:23 PM »
couldnt tell you the number off the top of my head.... i have gone back to uni, so am 3 hours from home, the F1 has been put into storage untill i get back from New Zealand, but i ended up puttin pods on it, so have changed everything anyway....those numbers were with the airbox  and uni filter..... i think the bike actually had more mid and low range with the standard air box....so to answer you question, i didnt after wards, i just rode it cos i went great NEway, and its a fight to get to the bloody needles NEway ;D.... sorry couldnt be more help....peace
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you are never to old, to act like a kid... be safe
funny thing,chasing someone down hill on a bike 30 years older than theirs..
he said \\\\\\\'it was like watching a 250kg unguided weapon getting stuck up you bum\\\\\\\ http://www.bikepics.com/members/trixtrem/

Offline Zeke

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Re: Dyno testing?
« Reply #15 on: July 27, 2006, 07:48:21 PM »
Y'all:

What's it usually cost to do a dyno test?  How many does it take to get dialed in?

How hard are they to find?

I am jetting my bike after 4 to 1 and would really like to get it spot on.  Seems to run crappy at sustained 3-4Krpm.

Thnaks

Zeke
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Offline MRieck

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Re: Dyno testing?
« Reply #16 on: July 27, 2006, 07:57:31 PM »
3 runs for 50.00 or so. It really depends on the operator etc.
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