Dyno Disappointment FM107"
 

Long story short. I had a FM107" installed with FM level b heads. I love riding it so my gripe is only dyno related. Got it in for the dyno today and the numbers are somewhat disappointing. Looking on Fuel Motos site they show a similar build to mine with 117 hp and 128 tq. Mine cam in at 102 hp and 108 tq. It's a long ways apart. What am I missing? My build is as follows:

FM107, Level B heads, TW-888 cams, Arlen Ness Big sucker air cleaner, power commander, Vance and hines xpipe and slashcuts.

What causes 15 hp and 20 lbs of tq difference?

How about you start by calling up Fuel Moto and asking them?

If there is a potential problem with equipment you purchased how about giving the vendor a chance to check it out / make it right before you spread it all over the net?

From what I have heard, all dynos produce different results. So you may have good numbers on one and bad numbers on another.

Also keep in mind that all kinds of things affect performance, temperature, altitude, humidity, fuel, air temp,, etc. Some or a combination of those could be the problem.

My numbers were also alot lower than Fuelmoto produced with the same bike. When I called Jamie and told him the temp, humidity, etc he told me that sounded pretty good for the conditions.

Give 'em a call!

Fuel moto's dyno could be off as much as 10% which would make sense. there dyno numbers are always really happy. if you take it to them I bet your spot on. ;-)

Is your pipe and compression all other components the same as the fuel moto dyno bike? If not that may be part of the reason.

put it on 5 different dynos and you will get 5 different results. IMO a dyno is nothing more than a tuning device so you can see what differences are made when you change something.
I raced cars for a number of years and we let the track times show the real HP numbers only used the dyno as a tuning device

it's all in the tune...most dynotuners suck at what they do. Look up Doc's performance and have him tune it and it will be a whole different bike

Piesik650 and I almost identical builds and we have almost identical sheets. Different dyno guys, very different elevation too. There is a 3rd bike I saw a sheet with a very similar build and almost identical numbers +/- 1 on all 3 bikes. And that bike was in the desert.

Did you actually have it Dyno Tuned? or, did you just have it dyno'ed while running a canned map to see the numbers it is making?

Just because its Dyno tuned doesn't mean it's tuned to the best of the engines cababilities. A lot of shops won't spend the time to squeeze all the power out. Exhaust is everything on these bikes too.

Who assembled it? Compression test? Leak down test? Rings seated properly for maximum performance? All of these things can lead to a mediocre engine.

I have found that most dynos are pretty close. They have corrections for air, heat, humidity and all of that stuff.

I have spent many times on the Dyno walking away disapointed. Need to find out what's holding it back?!? It's not what you have done, it's what you haven't done. I don't believe dynos are that far off, that's a lot of power.

Cam overlap and exhaust not getting along will drop power. Good luck.

As stated above, mph in the 1/4 mile strip never lies about hp.