Washbrook
Today I received an email from Indian Motorcycles advertising to turn my Indian into a Beast where if I bought a 2018 model I would get $7,610 in savings via a Stage 1 and a BBK 116 kit installed. As part of the advertisement they were quoting 15% more in torque and 20% more in horsepower.

2019-04-16_11-03-01.jpg 

That got me thinking, where are all these Numbers coming from? I could only find a reference to the torque on the Australian Indian site, being 151 Newton meters or approx 111 foot pounds of torque. Reading an article on https://motorbikewriter.com/indian-offers-116-cube-big-bore-kit/ Indian claims the kit increases power 20% from 54.6 kW (73.3 hp) to about 65 kW (87 hp) while torque is boosted 15% from 161.6 Nm (119lb ft) to about 185.4 Nm (136.7 lb ft). So here are some comparison figures I found fairly quickly from this forum site and a quick google search:

2019-04-16_10-46-50.jpg 

I do not quite understand the large difference in numbers between the Indian numbers for the BBK, be they HP or Torque and some of the other numbers shown on dyno results. I get that there will be some variations of a few HP here and there based on different year models, conditions, different Dynos, variations in air intake, exhaust etc.

Using the 1854cc BBK1 compared to the Indian numbers there is a 19 HP difference with actually 12 fp less torque? The AAMC BBK also reported 23 more HP whilst 21 less fp. My LLoydz kit seems to have only given me a similar HP to the BBK results being posted and less torque than the BBK even though we set it up for torque not HP.

What am I missing?
Are the comparisons shown too great in difference to really be comparable?
Are the starting numbers quoted by Motorbike writer wrong? 

I have seen lots of other dynos posted n various Indian sites, I am not picking on the above comparisons, they were just the easiest for me to find and use.
Norman Hall [aka Washbrook]
Man of Few Words
2017 Indian Roadmaster [Willow Green over Ivory Cream]
1999 Vulcan Drifter
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crash
Hey Norman,  I understand your frustration.  The question is 20% more of what and 15% more of what!
To make these claims, I would have thought that there would have had to have been a baseline that they were working from.  This baseline would then provide the starting point for these claims.
Looking at the indian web site for an RM, it states:
Peak Torque (95/1/EC Nm)151 Nm
So if we were to increase this value by 15% this would take the number to 

Peak Torque (95/1/EC Nm)173.65 Nm
Granted, this is at the engine, not at the rear wheel.  

So based on your base figures above of 73 and 119 respectively, we should be seeing numbers like 87.6 and 136.85

I do wonder if the numbers that are provided by Indian are at the back of the motor, not at the drive wheel. 
I suspect that the transition of torque and HP through the drive chain would diminish due to the elastic band and the shock absorbers in the rear wheel.  What we would be seeing at the rear wheel is a lot different to the raw figures that would come from a bench tested motor.
Ulysses #30673
IMRG #AU100394
Current: RoadMaster (ebony and ivory)
Highett Victoria Australia
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Biggles
The hp that manufacturers quote is measured at the crank and it usually says so in the fine print at the bottom of the ad. Rule of thumb for power loss to the rear wheel is roughly 10% for the clutch/transmission/alternator/water pump, another 5% for the chain. For shaft drive bikes its 5% for each 90 degree change in direction for the power flow. Of course we don’t have water pumps on our bikes so the loss would be a tiny bit less. This is the rear wheel dyno of my bike with stage1 & 2 and a dynotune PVCX. So going by this formula power and torque would be 97hp and 129 ft lbs of torque at the motor.FBF6E65C-1724-4BFF-B17B-3B5C1B500EE9.png 
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