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Your Dyno operator needs a refresher course! :rolleyes:

A few things:

-He needs to turn scaling on so that torque and hp cross at 5250 rpm.
-STD horsepower will always read higher than the usual SAE correction factor.
What about the air/fuel ratio graph at the bottom? It is the most important one.
Why did he start your runs at 5000 rpm?
Run 8 then run 9? What happened to the first few runs?


Other than that, your gains are good.
Bottom line, do you feel improvements at all throttle openings? That is what really counts.


John T
 

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Airfuel,

Thanks for responding. I do feel gains over the full range of the throttle- well at least upto to the 8-9K that I've taken it. Off the bottom the response is so much more instantaneous it seemed almost snatchy 'til I got used to tempering/easing my grip twist. Been doing too much time on my '06 GSX-R600- a bike with far less torque and hp. The throttle is more linear than when I first picked up the bike and she is so free flowing.

I wanted to post my dyno results because I said I would, but also to show fellow forum members how one example of a stock 910 dyno'd. My original stock 750S was a dog that was obviously fueled wrong. That's why I got the headers and PC in the first place. From early reports and my own break-in experiences on the 910 I didn't think that there were any issues with the 910. In fact I thought it was great. Of course I had no way of knowing how she dyno'd and if she would perform as advertised/implied. I had the headers and PC moved over to the 910 because I had them already and it would have been a shame to let them go.

I can see and feel from the results that I was right to do so. Now, I'm not a numbers queen. Saying I've got XXX peak HP so my bike is better than one with XXW is just bullshit. But it is nice to see the numbers and put them up for discussion since no other owners have put their own numbers up.

The guy who ran the dyno has an excellent reputation for his abilities. I have very little knowledge of dynos or running one so I can't really comment on his need for a refressher course- but the results that he's achieved on both my bikes have been nothing less than spectacular. He did say that the current version of the dynojet dyno software seems to have some issues and he was only able to generate that graph from a screen-shot, not the normal graph printing function. And I have heard similar things from other dynojet dynos on other forums.

Can you comment on why you believe the air-fuel graph is most important? To me that's kind of like showing how you solved a math problem- when I only care about the resulting differing HP & torque graphs and difference in the way the bike feels now.
 

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CB910 He did say that the current version of the dynojet dyno software seems to have some issues and he was only able to generate that graph from a screen-shot said:
Computer problems most likely, the latest software has been out awhile and zero problems here.

CB910Can you comment on why you believe the air-fuel graph is most important? To me that's kind of like showing how you solved a math problem- when I only care about the resulting differing HP & torque graphs and difference in the way the bike feels now.[/QUOTE said:
The a/f ratio is the main reason you put a bike on the dyno in the first place.
If the a/f is correct the resulting tq/hp will be the best you can get. There is also a difference to tuning for peak hp and tuning for overall performance/longevity.
Some bikes make better numbers if you lean them out a bit. Remember the old hotrodders saying "lean is mean" This is true to an extent but lean can also be hot. Dynojet gets their target a/f ratios from extensive testing for the most hp, longevity and most important driveability. I find the target numbers to be almost perfect 99% of the time.

So in other words, the a/f shows how your bike was and then how it is now with the better numbers. Just more information for you! Was your bike lean? Rich? combination of both and where? What is the resulting number 12.5? 13.5? Did he give you different target ratios for different throttle positions? You can get up to 3 different ratios for light throttle, mid and wide open throttle. A little leaner at light cruise gives better gas mileage while a richer mixture is better for wide open throttle.

Still puzzled why he started his runs at 5-6000 rpm, what is the bike doing below this?

Bottom line is how you feel. If you notice a better, smoother running bike and you are happy, that''s all that counts! :)
 
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