Well its been this way for the past 12 years of testing thousands of HD's and the 2017's we've run in house, still do the same thing. If you have your dyno results (raw data file) you can graph what DJ calls "gear ratio" and I would bet your going to find you clutch is slipping when in 6th gear. The new clutches in the '17's do not hold the stage III in the 107 versions we've done. We've added the AIM setup in them to stop it. So my guess is you 117 is slipping in 6th gear.

 

I misspoke somewhat. The dyno runs were 4th vs 5th gear, not 5th vs 6th gear but the same issue arose. The 114 dyno shows a significant difference between 4th and 5th gear yet the 117 dyno shows the exact same performance in both 4th and 5th gear (excluding limiters). I don't have the raw data files. Worth noting that its my belief that this particular dyno is slightly "stingy" based on past dynos run over the years compared to others dyno with the same bike. I view this dyno as "conservative", but that's just my opinion.

Here's the 4th vs 5th gear dyno runs on my 2017 CVO Limited completely stock 114. Both runs in this chart were the same day, same dyno, I was in the room. Green is 5th gear - 86hp/115ftlbs



Here's the 4th vs 5th gear dyno runs on my 2017 CVO Limited after the 117 performance kit (117 Cylinders, hi-comp pistons, hi-perf valve springs, hi-perf clutch spring, SE498 cam, Street tuner, Street Cannons). Both runs in this chart were the same day, same dyno, I was in the room. Blue is 5th gear - 106hp/116ftlbs (assuming it hadn't hit speed limiter)

 

We're not talking about deliberate tricks, we're trying to find out facts.

You can't be serious.

It is indisputable that doing a dyno pull in top gear vs a lower gear gives different results. Indisputable.

And you've gone from saying: "It's the dyno doing it" to "It's your clutch slipping".

Give me a break.

 

After reading this thread I'm surprised how many of you would rely on the instrument panel for an accurate top-end speed for more than a minute if in doubt.

We have GPS gentlemen, there is an app for that. If you suspect any monkey business with Harley's speedometers just DL any number of free GPS speed indicators on your smart phone and end this speculation.

You fellows might find (Speed Box) free app suited for this simple problem. It won't report over 120 mph so that's not really going to work for a thunderstorm but it sounds like it's enough for the Milwaukee eight limiter

 

You need to reread and understand things a little better. I have clearly stated that it is the dyno! Always has been that a higher gear gets higher results. When it doesn't something else is going on. In Heatwave's case I told him to check his clutch as it is most likely slipping and that is WHY he did NOT get an increase in a higher gear. I have run three 107 Stage III (114) engine kits and all three have had the clutch slip with the entire kit installed! We have added the AIM clutch kit to stop it so I assume that his 117 kit is doing the same thing.

 

Do you have the " Run Data" NOT the charts. If you do, use the free DJ software to view the runs but graph "Gear Ratio" on a second graph. It should rise up at the hit of the throttle then start dropping as RPM increases nice and smooth downward. If it stay flat or wiggles up and down then the clutch is slipping. You will not see it in the normal charts you have posted. On the 114 kit with ALL the same parts as you have they slip.

 

I read your comments several times before I made my post. I wanted to be absolutely sure I hadn't misread your statements. I didn't.

You statement: "...it's the dyno..." is obviously correct, in the abstract, because you're making the measurements on the dyno. It can't be anything else that is delivering the readings.

My point is that there must be a reason the 6th gear and 5th gear readings are different, because, obviously, the dyno cannot possibly know what gear the bike is in. The dyno is showing higher numbers in 6th than in 5th, so there MUST BE A REASON, and it's not "the dyno".

I have studied this, from multiple sources, over a period of years, and the consensus is that it is due to different power paths through the transmission; either through the cluster gear in 5th, (not all transmissions are internally the same), or direct drive in 6th.

Here's a good overview. Originally written in 2006 and updated in 2010:

http://drdyno.com/AIM_2010-06.html

Key point: "Whether five or six speeds, OEM Harley transmissions are direct drive in high gear. All the lower gears introduce the loss of two gear meshes..." He also brings up the very real point of loss due to tire load and sidewall flex over 130 mph.

If you have something other than "it's the dyno", I'm more than willing to listen.

 

Take a look at the required heat loss to get what you think is happening. Once you do that you would find the gears would be melting and that's just not the case. The HD transmission is spinning all the shafts and gears regardless of what gear your in.

So now lets talk about what you use a lower gear for. The lower gear increases the Torque output, that's why its there. If it didn't you could just take off in 6th gear all the time. So if you increase Torque at a given RPM you also INCREASE HP at that same RPM. That is the way it works!

HP= (torque * RPM)/5252

So explain how it can be anything but the dyno. You need to remember a DJ dyno does not measure HP or Torque. It measure the rate of acceleration of a drum and converts that to a reading. It does not take into account many other factors. Depending on what model DJ dyno and what software you use, you get different readings from the DJ too. There are errors in how they are doing it but we just have to live with it as it's the most popular dyno being used.

Now let's look at the rate of acceleration and where it has issues in the case of a DJ dyno. Since a lower gear multiplies Torque output, why doesn't it show up? Since a DJ dyno use a single pulse counter that gives one pulse per each revolution of the drum, any changes that occurs in less than one revolution gets missed. Then the software averages or smooths the numbers too. As you increase the gear (1st - 6th) the time period gets longer and you get more revolutions of the drum to measure and more speed. A typical 100 HP HD Touring bike takes about 23 seconds on the highway on flat ground with no wind in 4th gear to go from 2000 RPM to 6000 RPM. I have measured it many times. On the dynojet dyno with a high inertia drum plus the load brake weight it only takes 4 seconds to do the same. So there is apples and oranges in the weight factor to the real world. Now look at what happens when your spinning a light weight drum. Since each higher gear can turn the light drum easy enough the rate of acceleration is going to increase each time you raise the gear (1st - 6th) until you get it so high it cannot accelerate it any longer and this is why I can say its in the dyno.

 

As referenced in the dyno post i do not have the data files.

 

See if they will send them to you. If your happy the way it is great, but I can be pretty sure your running into the same thing we did when we upgrade the other three bikes. The worst part of it was I did not catch it right away and as we changed parts to get increased power the thing just did not respond as expected. Then I got to thinking about it and did the Gear Ratio chart, I was kicking myself, as I should have known better. Ordered the AIM kit and installed it and the performance jumped up 14 Ft Lbs. Mind you we had been making changes to the 107 Stage III kit, so now I have to go back to the stage III only and do it all over again. Two of the three bikes now have the AIM installed and the numbers came up.