F650 GS Dyno Runs FAQ

compiled & edited by Kristian #562; Scott, ID #1244
Please read the Disclaimer before attempting any work in this FAQ.
Last Updated: 18 April 2006

Also see the following FAQs:

Dyno Run #1 (OEM F650 GS Bike)

Original Link provided by Robert #1071


STD Horsepower (Stock Bike)
  • This is the Dyno Curve for a Stock Bike
  • BMW got it just right
  • I don't see any room for improvement with the Stock Bike setup

42 HP at the Rear Wheel
+ 6 HP Lost through the Clutch (Measured)
+ 3 HP Lost through the Primary Drive Clutch (Estimated)

51 HP at the Motor

Torque (Stock Bike)
  • The maximum SAE Corrected Torque of the 650ccm Motor is developed at 5.4 kg-m
  • At around 5500 rpm it starts to run out of puff.

Comments on this run:

Dyno Run #2: Dakar +Staintune +K&N +FuelNanny -O2Sensor

provided by Beau A #645

Dakar +Staintune +K&N +FuelNanny -O2Sensor
Here are the Dyno results from my 01 F650GS Dakar with these modifications:
  1. Staintune exhaust w/o baffle
  2. Airbox modification from Techlusion website
  3. K & N Airfilter
  4. Techlusion PowerBox (Fuel Nanny)
  5. BMW 7.0 software upgrade & injector
  6. 02 sensor has been disconnected also

The max horsepower and torque figures are at 6300 r.p.m.'s. There is a steady rise from both H.P. and torque from 3500 up to 6300. At present, one major area of concern was the constant stalling while approaching intersections stop signs etc. We tried to duplicate a stall on the Dyno but never did. What little time I got to spend on the bike this w/e, the improvements were significant. With the baffle installed, there was a 3 HP decline. I'll report back and please inform me if I need to go back to the drawing board on the Dyno.

Maximum Horsepower is 41.8
Maximum Torque is 39.7

My ace tuner is Brian Nallin and he builds dirt-track, and drag racing machines, (Rotax and H-D). I hope you will find this information useful and I am sure we will have more info in the near future.

You can reach Brian Nallin @
Phone (318) 631-6747
Fax (318) 631-9798
Web & e-mail www.nallinracing.com, nascar@shrevenet

Comments on this run:

Dyno Run #3: Fuel Nanny + Staintune (Techlusion)

From: http://www.techlusion.com/F650.htm

Before: 2001 F650GS w/Staintune Exhaust
2001 F650GS w/Staintune Exhaust and:

Dyno Run #4: Various S/W versions

by Robert #1071

Interestingly all three curves - old European soft 5000, 5000 with more pre-ignition and the current 8000 - are identical.

Unfortunately the AFR (Air-Fuel-Ratio)-meter did not work on that day.

Dyno Run #5: Two Brothers Exhaust

Dyno Run #6: Adventure Pipe

submitted by Rodnock

Dyno Test results of F650GS Snorkel modification, K&N Filter, Adventure Pipe exhaust, and Techlusion TFI systems

Dyno test results of Snorkel (intake plenum) modifications, and separately the addition of a K&N air filter showed no change in Horse Power or Torque output of the BMW F650GS over baseline. Adding a Techlusion TFI (1031) or "fuel nanny" and adjusting the pots for various exhaust system modifications resulted in 1 HP increase over baseline. The AdventurePipe aftermarket exhaust system added 3-4 HP between 3k and 5k RPM over baseline. Torque was also increased. Adding a snorkel modification, K&N filter, or Techlusion to the F650GS with AdventurePipe installed gave the same results noted above. These dyno tests were performed in Denver at an altitude of 5,280 feet. Baseline was a stock F650GS. It is possible that the results will be different at sea level, especially the Techlusion system results since this device adds fuel to the mix (bikes already run more rich at higher altitudes).

These test results indicate the most effective "bolt-on" modification to increase F650GS Horse Power is an aftermarket exhaust system. But, these dyno test results do not tell the whole story. Many F650GS/DAKAR owners report a "seat of the pants" improvement from a snorkel modification or K&N filter. This is most likely the result of better throttle response from these modifications. Improved throttle response provides better "driveability," especially at lower speeds and off-road riding, and will provide more "snappy" power delivery. The Techlusion system eliminates the surging problem found on many F650GS/DAKAR bikes, and this again is improved "driveability." Driveability improvements can be significant and can be just as important to the rider as an increase in horse power.

Dyno Run #7: Dakar with 15T Sprocket

Thanks to bmwmarathon

Only modifications to the bike are a DID X-Ring chain and a 15-toothed front sprocket. I'd be currious to see if anyone else has had their bike dynoed and what kind of numbers/ modifications that have been made.