May 17, 2003
Forums : General Discussions : Dyno Runs (241 Views)
May 17, 2003Just want to know, did you change out your rear tire before or after the Dyno?
Also, Why Dyno test a bike after mod's. Does it give you the ability to fine tune while on dyno or is it just a measurement of where you are now.
May 18, 2003I was thinking of doing my bike, but when I was told what the dyno does to your tires I kind of put that out of my mind. So long as I'm happy with the performance and I'm not looking to sell or show the bike I don't need it.
Keep an eye on your rear tire now, the dyno does a real number on them, or so I hear.
May 18, 2003
I have one of those old 1999 wimpy Evo's. I put it on a dynojet dyno twice.
First time was shortly after I got the bike with minimum mods as follows.
SE air filter, baffels completely removed, and a poor jetting job on the factory CV. I was told these bikes stock put out around 52 HP. Mine did 61HP and 68lbft torque after the above mods.
Second time on the dyno the mods were.
Mikuni HSR42 (dam good carburator), EV27 cam, jims big axel lifters, dyna 2000 ignition and the larger SE airfilter. This combination put out 72HP and 75lbft torque. Pretty good low end too. Since then, I added SE roller rockers and Vance&Hines straight shots. Low end improved with the V&H baffels in.
I guess that's not bad. I would like to see what a 5 angle valve job, clean up the runners and 9.5:1 - 10:1 compression would do to the numbers. I think that will be as far as I go. I need this bike to be over the road relieable.
May 18, 2003
Oh, the rear tire. The dyno my bike was on did absolutely nothing to my rear tire. It was just a steel roller with what looked like a big piece of friction tape wraped around it for traction.
Shinny side up...
May 18, 2003Ironhorse something is a little off. I have an 01 FLHTCUIA (they tell me the A stands for factory alarm). It had 37,500 miles on it and the tire had about 6,000 miles at the time of the dyno. My bike is 88" with high flow air cleaner, Thunderheader exhaust and Power Commander (no big bore kit) and I produced 76.2 HP with 90.2 Torque (max. numbers). Elevation and humidity also come into play with fuel injection as well as the temperature of the motor. If they do more than one run, your first run is going to be the best if it's not allowed to cool down just because the motor is heatsoaked.
What kind of exhaust do you have? How many miles on your rear tire (is it getting down to the wear bars?) What elevation are you (the dyno) at? What is the relative humidity there?
I can offer a few suggestions after seeing the answers to the above. I would be concerned with somebody telling me to "not get caught up in the horsepower/torque game" and he's running a dyno or selling me parts. This is Harley Davidson....what language is he talking?? That's exactly why we spend the money on more and more and more.
Riding an Ultra Classic you probably know that torque is very important. That's what gets these monsters rolling. Email me if you want and I'll scan and email my dyno sheet for you to take with you and it's 88" not 95" like yours.
May 18, 2003I'm also concerned that you couldn't get the Power Commander to work. Did you have a shop try for you? Get back to me on this one, too. Oh and did I ask what exhaust you have? Is it dual or 2 into 1?
May 18, 2003Chemdog a dyno does to your rear tire what a burn out does, if even that. If you dyno over and over and over then yes, you're going to tear a tire up in short order.
I ride hard everytime I leave a stop.....so a dyno is just one more time of twistin' the throttle.
May 18, 2003I agree.....don't spend anymore money (unless it's on a 2into1 exhaust). But what I am saying is that a 95" motor should be producing more HP and Torque than my stock motor (we have the same year and model bike, but that's irrelevant). And my dyno sheet is not the best I've saw for a stock motor.
They are different from one dyno to another and from one operator to another but they don't very greatly. Or at least that's my experience. I'm riding a bagger now but I have had many fast street bikes and have been in the magazines, a hardback book (Rebels With A Cause by Gail DeMarco pg. 104 and 105) and a movie "Rescue Me", with some of my bikes.......been there, done that.
If you think it's the dyno, take it to another. At this point I'd have to say that I'm skeptical that it's they dyno.......they couldn't even get your PC to work right. You might want to think about taking it to a shop that specializes in performance.
May 18, 2003I had mine dynoed this weekend and was soo disapointed. Only came up with 82.8 hp out of a 97 evo 80 inch bike. This was the first time I have ever heard my bike from the backside also (can you say earplugs). I also noticed for the first time how rich the bike is running (big black cloud). I could never tell this before cause when I'm pulling the wick I like to concentrate on looking forward. It has always had a little hesitation on the low end, but I always attributed it to the high lift cam. Found out first hand its way too rich. I have an appointment now to get it dyno tuned once and for all.