A motorcycle weighs the same amount whether on a dyno or on a track. Friction of the tire simply spins the wheel it rests on rather than propelling the bike forward. As a previous poster stated, I guess this will never be settled until someone posts that has taken their bike to the track and also done the dyno drag with the same bike.

 

i'm sure that they could get a number/time that would be semi close but the track isn't as perfect as the dyno. weather conditions, altitude, track conditions, bikes suspension/launch. all these factors make a big difference in times. a 9 sec dyno drag run is not a 9 sec run at your local track. i'm gonna get flamed for this but, its almost like an adult video game. you know what one i'm talking about, the one where you sit on the bike and lean it over from side to side to go around the track on the screen. meaning no disrespect to anyone who does this, i'm sure that it's a good time as all you above have stated but ,thats what it reminds me of. flame away.

 

Let it go Louie.

Is it perfect? No.

Is it for everyone? No.

So what.

 

Not so much for the HD's but I have seen high hp bikes thatthe tires wiil slip on the drum.I saw a Hayabusa that has around 275 hp only pull 147 hp on a Teresi dyno truck because of that.Bike runs consistantly in the 8's on the track, but not on an 880 pound drum.I think they're kind of cool, I'd never do it, especially after actually going down a 1/4 mile track.Just sitting there would'nt do it for me.

[IMG]local://upfiles/11733/C8252E6F1902436AA68477E58DC8F9AC.jpg[/IMG]

 

Need to see one in person to really dig it!! I think its pretty kewl to watch. Its funny watching the guys that dont know what their doing go through the gears!!!

 

According to thedrag dyno operator, hekeys in differentweight/air drag factors for different types of bikes. He also statedto me that actual 1/4 mile ETs are usually a little better then what hisdyno drags indicate. It's just another game to play with bikes, some like the game some don't. It's like comparingother types of racing,many road racers don't understand the drag racers andvice versa.

 

Dyno drags are portable and great for events that don't have a drag strip. They're also up close and personal. I like them, they're fun. [sm=smiley20.gif]

 

In the real world you're accelerating the mass of the bike, hence a 400 lbs bike will accelerate quicker than an 800 lbs bike (given the same hp). On the dyno drags however you don't actually have to move the weight of the bike forward, you only have to spin the drum. If nothing is done to correct the weight difference, both bikes will feel the same drum resistance.

Thanks. That makes sense.

 

I have a friend thatis a mechaincfor Doc's HD in the St. Louis area. He also buids race motors and travels around a races on the dynos.In fact, he was one of the guys that was racing and was interviewed on that show for V-Twin magazine.
I think they are cool because thay are portable and can be set up at many events. Looks like great fun to me.
Phil

 

You obviously don't get it! It's all about who gets there first.