Dyno racing!

[Steve in Sunny Fla]

Both Concours. Which bike is faster - and why?

[Rhino]

I'll take a stab. Mike_Dionne is faster because the power comes on at much lower RPM.

[maxtog]

I'll take a stab. Mike_Dionne is faster because the power comes on at much lower RPM.

I think that is just a data collection issue.  In the case of the red plot, the usable data only starts probably around 3.6K RPM, so you have to start there in the comparison.   I doubt the red plot is really saying there is only 10hp at 3400 rpm and suddenly has 80hp more a few hundred RPM later at the blink of an eye    This is pretty common on the dyno plots I have seen; it depends on what gear is being used and when the plot is started.

[Steve in Sunny Fla]

I think that is just a data collection issue.  In the case of the red plot, the usable data only starts probably around 3.6K RPM, so you have to start there in the comparison.   I doubt the red plot is really saying there is only 10hp at 3400 rpm and suddenly has 80hp more a few hundred RPM later at the blink of an eye    This is pretty common on the dyno plots I have seen; it depends on what gear is being used and when the plot is started.

correct on that issue. Posted elsewhere on the net, nobody seems to have figured that part out yet. Still, the question remains... Which is fastest?

   steve

[Rhino]

correct on that issue. Posted elsewhere on the net, nobody seems to have figured that part out yet. Still, the question remains... Which is fastest?

   steve

In this case, the bike with the better rider will be faster.

[turbojoe78]

The red one.  From 4000 rpm's on till shut down it's pulling harder.

[Steve in Sunny Fla]

The red one.  From 4000 rpm's on till shut down it's pulling harder.

well that would certainly appear to be the case, But all is not as it appears...

steve

[Conniesaki]

Still, the question remains... Which is fastest?

   steve

Define "fastest". Top speed, or acceleration? My answer is: Red = Blue. i.e. same.

They can both make it to redline, and with the same gearing they'll be equally "fast".

[maxtog]

Define "fastest". Top speed, or acceleration?

That was my first thought, but I assume he meant acceleration.  Then I thought it was a trick question (like many us of probably do) and it might still be.....   

They can both make it to redline, and with the same gearing they'll be equally "fast".

Technically, on the graph, neither was tested to redline, which is as least 10K (some claim the tach reads 0.5 high at the top end so 10.5 = 10).  And there is no usable data from the red one under 3.6K, which although typical for many dyno plots, is still  important to know

[Steve in Sunny Fla]

So let me toss out a hint... read the title. Steve

[tweeter55]

Neither one...they're both strapped onto a dyno & can't move, hopefully.

[maxtog]

So let me toss out a hint... read the title. Steve

LOL- maybe they are two bikes on the same dyno at the same time??    That would be strange.  Perhaps it is the SAME bike, and these are readings from two different dynos....

[Steve in Sunny Fla]

  Perhaps it is the SAME bike, and these are readings from two different dynos....

   and THAT would be correct!
 
   So one might wonder what the point is. Simple, actually  - - to dispell some misconceptions about the infallability of dynos, and the mistaken thought that we can tell which modifications are better than others when the testing was done on different dynos.

  The bike used here is in the exact same state of tune on both, yet one dyno clearly gives it a strong edge of 5-6 hp for the entirety of the comparative run. In this case, the bike is the standard that the yardsticks (dynos) are held to. Which dyno is closer to correct? who knows... all we know is that they are clearly not measuring the same.

   To me, this is important info because often we make farkle choices strictly by the dyno chart This can still be done, but to give viable info the modifications need to be compared on the same bike, on the same dyno, and in as comparable weather conditions as possible. Then compare the percentage of change.  This should give a more clear view of the actual performance changes achieved. we need to get away from just looking at dyno charts and seeing which shows the highest hp or TQ... and buying that product. If the measuring devise isn't constant, the results are just not reliable. Steve

 

[maxtog]

 



I took way too many courses in statistics, so I will totally agree with you.  Sample size and repeatability are both extremely important when evaluating things and trying to draw a conclusion about something.

[kzz1king]

Who won ?

[Steve in Sunny Fla]

you did! 

Steve

[kzz1king]

HaHa!>

[Conniesaki]

Then please direct me to the owner of the red dyno. I want my bike to have more horsepower and torque without me having to buy anything.







 

[Steve in Sunny Fla]

Then please direct me to the owner of the red dyno. I want my bike to have more horsepower and torque without me having to buy anything.
 

    That would be Chris Jones, Chiefland Fl. Chris is a world champion engine builder / tuner, he built the zx14 Ricky Gadson set the world record on. He's had so many 500 +hp pulls on that dyno I think all the friction is worn out of it!  The blue trace is from my dyno which had very little use before I bought it, and the electronics were just refurbed by Dynojet less than a month before that run. Steve

[gPink]

If I recall Chris also built a turbo C14 for a guy that was around the forums for awhile.