Hi Rustman -
The difference in dyno readings are that the EC997 dynos read the actual power that is transferred to the drive roller by the rear tire.
The Dynojet numbers are always higher that anybody elses dyno -
The explaination is here:
http://www.factorypro.com/dyno/true1.html
That is a comparison, over the years of the "average" dynojet dyno comparisons as compared to TRUE HP scale, rather than DJHP (dynojet hp).
http://factorypro.com/magazine/mag_cyclecanada_Dynojet_dyno.html
If you look at the chart, you'll see that your 145 True is about 172 to 176 djhp.
Why does dynojet read higher than any other dyno?
(just watch for the rebuttals!!!)
They did something odd in 1990 and just never corrected it. There's more to it that's more technical, but -
For fun - take a recent file and view it in the DOS version of their software and it will read about 2% lower than the Windows software. Weird and they didn't fix that either.
One problem with the dynojet's are that they still run a knurled drive roller (which creeps excessively at high hp - reading lower than normal djhp) and not the newer "slotted" drive roller style.
You can see that if you look at the rear tire after a test - If it's shiny looking - it was slipping. Some places spray adhesive onto the drive roller to try to minimize the slippage error.
Tires slip all the time on the dynojet dyno at the AMA races on bikes with less power than the Busa's put out.
As far as what gear the bike is tested in?
Can we get a real description as to why 4th gear is a magic gear?
If anybody thinks that the load on the bike in 4th gear is anything at all like what the bike experiences when you are riding the bike for a topend run - they are mistaken - and I think that anybody can see that.
One of a dyno's primary jobs is to duplicate anticipated loads - and that's certainly not a 8 second scream through 4th gear.
So - the only reason why a bike should be tested in 4th gear on an inertia dyno is because somebody "trained" somebody to do it - certainly not a reality based simulation of real world loading!
So - Without tire slippage AND on an AVERAGE reading (dynojet's wander +/- 5% to 7%) would be pretty damn good.
And don't even get me started about the customer scaring "Tuning to an Air/Fuel Ratio" scheme....... being correct in any way except by accident - It certainly flies in the face of reality.
I see silly stuff like an engine running well at a dynojet "17:1" af rations all the time - When they richen them up? They run worse.
You'd be smelling gas when you slow down with a tailwind....
Tuning to Best Power guarentees that you have the proper amount of fuel and ignition timing..... Tuning to an a/f ratio is not.......
Yes - I do design dyne systems for a living.
Cheers!
Marc
<!--EDIT|Marc Salvisberg
Reason for Edit: None given...|1075597605 -->
