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backcracker
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Discussion Starter #1
I am curious what is the best type of dyno to use? I have found one near me that a cycle shop uses but am not sure if it is any good. The only thing I found out is that it is a Dynojet and the guy has over $40,000 invested in the dyno room. Any suggestions for what to ask or what the recommended specs should be to get the best results?

Thanks,

Dan
 

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Are you buying it?If it's just to test on it does not really matter because everyone is different.The peak gains"after mods" and Air Fuel ratio are the main things.Some dyno's read lower than others the key is seeing and inprovement from your baseline! :cool:
 

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Dan,
There is no such thing as a best Dyno. A dyno is just a tool. If you do a run on any dyno then program,tune,modify or do anything to your bike, make sure you use the same dyno with the same tire pressure, temp,etc. in order to determine whether what you did was positive or not. Do one thing at a time, that way you will know what works and how much it increased performance.
I will bet that if you do consecutive runs, there will be a difference in your #'s. The 2 major differences between platform dynos, is that one will be an inertia and the other will have a load capability. The load is used to simulate real conditions found on the road. Hope this helps.
Derek
 

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SNAFU
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Derek and Kaz are right, there is no "best" dyno but there are some that are better than others for tuning EFI bikes.

There are 2 types of motorcycle dynos, Inertial and Brake. The majority of dynos at dealerships are Inertial dynos made by Dynojet. As the name implies, they measure inertia, the force required to accelerate a known mass, to calculate torque (horsepower is nothing more than torque vs. RPM / 5252). Used in conjunction with a exhaust gas analyzer they are great tools for tuning carburetor bikes and setting WOT (wide open throttle) fuel and ignition settings and diagnosing gross errors on EFI bikes but they are very difficult, if not impossible to use to set steady state variables such as partial throttle cruise (where you might get surging, poor fuel economy, popping, etc.

A brake dyno is one where a force is applied against the rear wheel. The force is measured to calculate torque. Because it applies a counter force rather than relying on inertia it can hold the bike at a steady RPM allowing you to take AFR reading the more closely approximate the way the fuel maps are programmed. These dynos are made by Mustang/Factory One and Land and Sea to name the top two.

Dynojet has responded to the challenges of EFI tuning by creating a hybrid dyno that utilizes both the inertial wheel and an electronic brake. That's the DJ250+brake version.

So, IMHO the "PREFERED" dyno for our bikes is the Mustang/Factory one, followed by the Land and Sea then the Dynojet 250+brake. :)

Sorry for the long winded reply.

Mark the dyno geek ;)
 

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Riding around
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Mark - your replies are NEVER long winded! They are always just right for me - detailed enough that even I generally can understand them and they NEVER come across as patronizing. Thank you for your "long-winded" replies!!!

Val

 

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Val,
You better Quit Flirting! Your My Girl and I don't Share!:1273:
 

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Don't make me have to Spank you!:spank2:
 

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:eek:fftopic :slap2: ;)
 

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backcracker
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Discussion Starter #11
Thanks for the info guys, I really appreciate it. I only asked about best dyno because I heard someone mention that some only go up to so many RPMs. I suppose all I can hope for is a great running bike after all the mods. Thanks again, you guys are the best. :notworthy
 

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spit happens
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in 15 min I am headimg off to the dyno.
I did a bunch of mods and hopeing for a increase in power.
Also get rid of the hiccups and coughing rite off idle.

Let everyone know later,what the results were.
 

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You found a Trailer?:plause Keeps us posted!:cool:
 

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Ironbutt
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Mark, Great info. Thanks
 

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spit happens
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Super Kaz said:
You found a Trailer?:plause Keeps us posted!:cool:
And it was worth it :thumb

I'll post the dyno sheet when I can get a good enough pic.

I gained again.
 
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