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Discussion Starter #1
Been To The Track Lately And Noticed That My Bike Pulls More Or Less Depending On The Run
Sometimes I Run 10.70 Other Runs 11.00 And Others 11.30
Could It Be Our Unbeloved 6.xxx Version Or Gas?
From What I Noticed It Seem's That The Computer Senses How We Ride And Gives Performance According To The Latest Drive.
I.e. If We Drive Like A Grandma It Performs For A Grandma And So On.

Anybody Else Noticed This?

Last Week I Did A Strait Pull In 6 Th Gear And It Topped At 240 Kph

Now It Cant Be The Clutch ,the Mecanics Had A New One In Just 2 Weeks Ago And I Run Only Mineral Oil(motul),and Have Ken's Race Filters In And The Stock Can.

I Even Had I Run At 11.79 , It Was Just Not Pulling!my K12rs Was Faster Than That

Marc The Stroker
 

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I've noticed my 06 KS (ver. 6.0, stock exhaust, 93 octane) feels like it varies in acceleration performance. Sometimes it feels faster than others, even on days with similar temp and humidity. However without objective measurement, you can't be sure.

Your numbers may indicate it's really varying. Don't know about the KS but the ECU on modern cars will often pull timing, richen mixture -- whatever it takes to preserve the ECU's idea of safe thermodynamic margins. This can cause performance to fluctuate somewhat. It's usually more pronounced with temperature changes.

However my bike did three back-to-back Dynojet pulls with almost no cool down time in between. Each was within 1 hp of each other (about 140 hp rear wheel). That implies in that specific case hp output wasn't affected by heat buildup.
 

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Discussion Starter #3
it was fine before i had version 6.0 loaded in the bike!!!!????
what's up????????????????

stroker
 

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joema said:
I've noticed my 06 KS (ver. 6.0, stock exhaust, 93 octane) feels like it varies in acceleration performance. Sometimes it feels faster than others, even on days with similar temp and humidity. However without objective measurement, you can't be sure......
If you're using the same fuel then I suspect variations in "air density" could be causing fluctuations in output. Inlet air temp is the major variable along with relative humidity and barometric pressure at that time. All these variables fluctuate throughout a day and will cause output variations.

A dyno is always gonna be more precise than the "seat of the pants ometer" but dynos also should be corrected back to a standard rating for set ambient conditions - it's the only way I know to make a meaningful comparision between dyno runs separated by time and changes in conditions between those runs. If an ambient standardised comparision is used there is a lot less logistical issues with changing conditions, parts installation, dyno time and access etc etc.

A few measurements of ambient conditions while at the track may be worthwhile. If you're looking for accuracy for an ambient temp a good start is to shade the thermometer from direct heating by the sun and take a reading at the same air inlet height above the road surface that the bike will be running over. The temperature gradient above a dark ashphalt track surface is not the same as in the pits.

This site may be useful: http://www.csgnetwork.com/relhumhpcalc.html
 
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