I know a lot of us on this forum like to talk about hp and torque numbers. I am not criticizing anyone, as I have gotten caught up in it myself - chasing mods and numbers that others claimed. Over the past few years, I have had the bike Dyno tuned 5 times as I made repeated mods that would affect the EFI map. I should have just bought a self-tuner years ago and saved a lot of money!

Anyways, I have had bike tuned by four different shops - first by a reputable tuner in Dallas (93 hp/103tq with SE 204 cams and V&H BR 2-1). Then changed pipes to 2-2 Bassani pro-pipes and had tuned by a guy near Houston. He told me decent numbers (mid 90's), but bike did not run well and felt sluggish, so I took it back to Dallas. He ran a baseline Dyno prior to tuning and numbers were way below what Houston shop claimed. Then he tuned and gave me upper 90's in both hp and tq. The Bassani pipes kept coming loose at the headers and I wanted more power so I bought a Fatcat 2-1 pipe and retuned by shop using Tuning Link software - numbers were low - upper 80's, but bike ran decent and definitely better than the second tune by Houston shop. Finally, I decided to change the SE204 cams out for some TW6 cams and bump compression to 10.2 range. Also changed pipes to Bassani 2-1 RR as bike got got hit by truck and trashed Fatcat. Had tuned by Lozano Brothers in New Braunfels. I was a little disappointed, as numbers were again in mid to upper 90's - I was hoping both hp and tq would be 100+ with Woods cams and more compression. Plus, I read all these guys getting 110 ft lbs with these cams. I just got a chance to ride it and get on throttle, and the bike pulls really hard - I rode up a hill in town and hit the throttle and felt like I was getting pulled off back of bike. Mid range is just real torquey, definitely stronger than any of the previous set ups, but looking at Dyno charts or peak #'s, you would never think it would run faster. Torque even hit earlier with the V&H BR 2-1 (90+ tq starting at 2000rpm), but bike just feels stronger now down low and thru mid range.

A lot of typing and info to make this point: dyno tuning is an important part of getting EFI bikes to run well, but tuners and their dyno's vary so much in their skills and calibration of their equipment, not to mention inflating numbers, you just can't compare Dyno numbers unless they are done by same individual and Dyno. This is the first time my bike has had that real strong snap in throttle response from a dead stop since I changed the stock cams, but if you just looked at Dyno sheets, you would have wanted the set up I had a couple years ago. Bike always pulled strong mid thru upper range with the 204's, but now bike pulls stronger down low and mid range is kind of scary if you aren't holding on real tight. I did not get a chance to get it on highway to test upper range, but based on how hard it was still pulling when I had to back off on my hill test, I can't imagine it is going to disappoint.

Be careful with bragging on Dyno numbers, sometimes they just don't add up to real-world power.

 

One of the reasons dyno guys are inconsistent with each other is because they tune with different strategies. Some tune to get maximum hp. Some for the maximum torque. And then there's flat AFR tune, high MPG tune, high RPM tune, etc. And then there's the good 'ole "all around" tune. Tell the operator what you want and have him tune for it.

 

I understand what you are saying, but I thought that one the main advantages of EFI is they can be tuned for power and fuel economy by dialing in each throttle position. I guess each position could be still be set up for max power or max economy. I was talking to a tuner awhile back about setting the bike up for power or fuel economy and he told me there is no reason you can't have them both when setting up the VE table.

 

I have never lost power to have a good riding bike. It's all in the tuner, I had my. 06 on 7 different dynos and all were within 1 hp.

I've made thousands of dyno runs and there is always consistency

 

I think people get way too caught up in dyno #s. Yes, it is an indication of PEAK hp & tq, but where it makes those numbers in relation to how you ride is more important.
IMO dyon tuning is essential is you want your bike dialed in perfect for your setup, but the peak numbers don't tell the whole story about how it is going to perform in real world riding...it's more about the curves.

I've riden bikes that look far more impressive on a dyno sheet as far as peak numbers go than mine that didn't translate to on street performance. My numbers aren't that impressive, but the hp & tq curves peak early and run out through the whole rpm range, which makes it perform well in real world riding such as passing, rolling on the throttle in 5th or 6th, low rpm torque, etc.

 

you have to keep in mind that there are different kinds of dynos as well. the friction dyno and the water dyno. not usre of the technical names of them but none the less. each one will be differ they say the one that uses water is the better one but who really knows. I also think its pretty obvious that if you have one guy dyno it and then another guy dyno later its gonna be different just due to the styles of the guy tuning that's why I only use one guy

 

^^^This

Dynos are just a tuning tool, the numbers themselves can be manipulated based on atmospheric conditions, what gear it was run in, etc. the real point of them is to get a good smooth power band with consistent AFR. dont worry about the numbers themselves as they will vary based on the parameters used for that particular dyno.

 

You were close. Both of the types you mention are types of braking or load control systems used on a dyno. The two types of dyno (to my knowledge) are the Inertia (DynoJet) or the Direct (Mustang/Factory Pro/etc). The Inertia type measures how long it takes to accelerate the drum with known parameters (diameter, weight) to calculate torque. The Direct type uses a strain gauge to measure the torque absorbed by the roller.

As for the braking types mentioned they are Water or Eddy-Current. I'm not so sure that the Water is superior to the Eddy Current, in fact I'm pretty sure it's the other way around. Regardless, this is how the operator "holds" a certain RPM and MAP (or throttle position) while taking an exhaust sample. He then repeats this in as many cells as possible to tune the engine over its entire operating range. Also, with the Eddy Current type, there is no friction since nothing actually touches to create braking effort. It is the act of passing a steel or iron core through a magnetic field that provides braking. Vary the strength of the field and the braking effort is changed.

HTH

 

I agree with all the comments. Just found it interesting to have all the Dyno numbers and curves, and then ride the bike and realize the numbers just don't always translate into power on the street.

 

At least you figured this out. You are in the very small percentage of those that have.