The standard offering from DJ ia a speed control dyno(no load brake). An option on a Dj is a load cell(strain gauge or some method of measuring Torque and a brake). The DJ models have just one trigger for drum speed, my Dynastar has four(will be more accurrate and stable) another manufacturer, DynaPro, has 16 triggers(even more accurate and stable). horsepower = torque * rpm / 5252.
So I know the weight of the drum, under a load the strain gauge gives a value, the drum has the optical triggers to calculate speed, and we are using an RPM pickup for RPM. On DynaStar, Torque is measured and HP is calculated from the collected infomation off of the drum. What you paid for was a tuned motorcycle that is smooth through the RPM range and when you go WOT will get you all that it has. That is the reason for running the baseline before tune and then a final after tune. That number increase is part of what you paid for but a bike with great driveability/rideability is what you will be most happy with. You can see from the dyno chart what the increase in HP and TQ was regardless of the final numbers. The real question is how many DJ's out there have the load cell option? You watched my method of tuning and I could not do that without a load cell and eddy current brake. I have not run or looked closely at a DJ. DJ is the motorcycle industry standard. When I was researching Dynos I looked at them all and I chose the one I have based on features, capability and end results of tuning. The tune on a non-load cell dyno will not be near as good as on a dyno with a load cell. I try and tune to an overall quality level on each and every bike and I can get there with my DynaStar. I believe the numbers from my DynaStar to be accurate, but as I said earlier there is a lot of calibration and consistency that has to be done to maintain that accuracy.