All dyno results are "As measured on DYNOJET'S MODEL 150 DYNAMOMETER".

Except for the before and after Buell graph, all dyno testing was done by Steve Kirby at Kirby's Motorcycles and Machining, Grover Beach, CA, 805.489.8693.  The Buell graph was lifted from the Battle2Win Summer 1997, Volume1, Issue 4 magazine article written by Kip Woodring.  Battle2Win is a fine new magazine, put out by the publisher of Thunder Press, which focuses on Buells.  The Buell dyno testing was done by John Hoy of RPM Cycles in National City, CA, 619.474.8451.
 
Those who are used to real dyno data will notice that these results tend to run about 10% above that which is normal for these hopped-up engines.  This is due to the WhiTek ECS.  Putting an ECS on a stock engine will result in an even larger proportional gain.

These curves compare a stock 49-State big twin with a bike that has been modified by only the addition of the WhiTek ECS.  Here, horsepower has been increased from 53 to 64, for a horsepower gain of 21%.  Torque has been increased through the midrange from 58 to 72 foot-pounds for an increase of 24%.

 
This graph shows horsepower curves from three different engines.  This shows how much one can hop-up a Harley engine, at two different levels of effort.

The top graph is from a very hot-rod (for a street engine) 93 inch EVO.
The middle graph is from an 80 inch EVO with standard hot-rodding.
The bottom graph is from a stock 49-state big twin.
More details about these top two engines are listed below, where their dyno graphs are listed separately.

1200 cc Buell, courtesy of Battle2Win magazine and Kip Woodring.  These graphs show that a stock Buell is pretty well set up for a dyno shootout (peak horsepower). This is implied by the fact that the peak horsepower was only increased by 3.1 HP (from 76.8 to 79.9) at 6300 RPM, an increase of 4%. The chart also shows how much faster the bike can be made by proper care and feeding.  The torque at 4000 RPM is up by 20.3 foot pounds (59.8 to 80.1).  This is an increase of more than 33%.  A rider will find that he spends NO time accelerating through 6300 RPM (where the horsepower peaks), but ALWAYS accelerates through 4000 RPM (where the torque peaks).  With a 33% boost in torque in the hot-rodding area of engine operation, the WhiTek version will eat up its stock competition.

While we're looking at Sportster engines, look at this one.  These graphs come from what we believe to be the world's first electronically-fuel-injected nitro bike.  The engine that made these curves is pictured in our page about  Bonneville.  The lower curve was running straight alcohol, for a max 106 HP.  It barely warmed the engine up (alcohol is nice that way).  The upper curve is the same engine running 66% nitromethane.  It made a max 137.1 HP.  This is a 1291-cc motor with real high compression.  The compression is fitting for the lower curve (alcohol), but is probably too high for the top curve (nitro).  We won't know for a few months, but it is suspected that the top (nitro) curve is lumpy due to detonation. Modifications to the ECS to manage these fuels were limited to using a larger fuel pump with nitro compatible seals, a higher pressure fuel pressure regulator with nitro compatible seals, adding two more injectors to the intake manifold, and swapping the two injector drivers on the MCU circuit board for higher current ones that would drive two injectors each.
 

This engine makes the most power per cubic inch that we personally have seen tested (naturally aspirated, gasoline that is).  This is a 93 cubic inch EVO with an ECS-46 with an oversize air cleaner, Alan Johnson heads, Crane H-304-2 cam, Cycle Shack shorty duals without baffles (pretty drag pipes, in other words), and the engine was built by Steve Kirby.  Lyle in Bakersfield owns the bike.  He gets over 50 miles per gallon on road trips.

This engine is a normally hopped-up 80-inch EVO.  It has high compression (maybe 10:1) heads with porting, an EV46 cam, and a Thunderheader.  It makes a max 79.9 HP and 83.8 foot pounds or torque.  It belongs to Bruce in Atascadero.  He has it installed in an FXRD, the dresser that was such a good model that the factory only made it for one year.  Packing his wife Mary he will commonly run off from single riders on carbureted, hotrodded bikes.

This is an 80-inch shovelhead with the ports cleaned up but not enlarged.  It has a Sifton 112 mid-range cam, stock header with crossover, dual SuperTrapp universal mufflers with 14 baffles each, 9.5:1 compression pistons, and a WhiTek ECS-42 system.  Being a fairly lightweight bike and making 80 foot-pounds of torque, it runs off from most EVOs, even with a passenger on the back.