Why aren't there more Turbo Busas Roadracing?

[Audiomaker]

...at the amateur level?

Sorry for not posting this in the "Turbo" forum, but I wanted to get the big picture from some road racers that might not get into that forum too often.

So yeah... I check out the road racing vid's and whatnot...nice bikes, looks fun. Always gets my adrenaline up watching but I have yet to see a turbocharged bike on a twisty track.

Plenty of drag vid's though of course.

Does putting a turbo on your Hayabusa kill it for competing in the curves?

Sean

 

[phil823]

to much power the keep the front down? (without a stretch)
eats the ****s out of tires?
turbo is even more weight?

 

[Tufbusa]

...at the amateur level?

Sorry for not posting this in the "Turbo" forum, but I wanted to get the big picture from some road racers that might not get into that forum too often.

So yeah... I check out the road racing vid's and whatnot...nice bikes, looks fun. Always gets my adrenaline up watching but I have yet to see a turbocharged bike on a twisty track.

Plenty of drag vid's though of course.

Does putting a turbo on your Hayabusa kill it for competing in the curves?

Sean

Yep, it sure does!

to much power the keep the front down? (without a stretch)
eats the ****s out of tires?
turbo is even more weight?

And this is not the reason!

 

[Audiomaker]

Yep, it sure does!



And this is not the reason!

Well OK then! LOL!

 

[dadofthree]

Well Tuf

 

[SWJ88]

you just got to get bigger balls. and more weight? who cares about 35lbs or so when the stock exhaust weighs a ton. a 35 lb power adder that adds another 200 hp? YA CANT FN BEAT IT! you are king of the road for a fraction of the price of anything else that comes close.

 

[Audiomaker]

Well Tuf

55,000 posts? How did you even have time to be a dad of 1 ?

 

[SWJ88]

55,000 posts? How did you even have time to be a dad of 1 ?

lmao, but honestly i dont think superman could harness all the power of a turbo busa but its gotta be the best feeling in the world to try.

 

[Audiomaker]

lmao, but honestly i dont think superman could harness all the power of a turbo busa but its gotta be the best feeling in the world to try.

Really sorry.... that just kind of took my breath away.

55,000? That's 25 posts a day, 7 days a week without fail for the last 6 years!

I'll try to get back on topic. I'll really try.

Sean

 

[05 Busa LE]

I think it may have to do with the fact that lap times are affected more by cornering speeds (that is, braking, turning, and exiting) than straight-line speed. The biggest problem is transmitting as much power to the rear tire without chatter and spin. Sometimes, too much power when exiting a corner may cause lap times to lag, which is why teams like Ducati use GPS to determine where to limit power application around the track. They also experiment with different engine configurations and frame flexibility to try and control traction.

 

[Audiomaker]

I think it may have to do with the fact that lap times are affected more by cornering speeds (that is, braking, turning, and exiting) than straight-line speed. The biggest problem is transmitting as much power to the rear tire without chatter and spin. Sometimes, too much power when exiting a corner may cause lap times to lag, which is why teams like Ducati use GPS to determine where to limit power application around the track. They also experiment with different engine configurations and frame flexibility to try and control traction.

Yeah, OK...whatever.... but did you notice that guy up there has 55,000+ posts?












(Just kidding.... that explanation makes perfect sense and Thanks!)

 

[Busashot]

Ok let's be specific here. What kind of power output are we talking? Stage I @ 240hp?

If your going to run a turbo on a road race course you have to treat it like it is NA. I would gear it similar to being NA. Rev quick and not as much load on the engine to create such a huge amount of TQ when in full boost. Street turbo bikes or cars excel at higher than normal speeds because typically they are geared like stock or less. There are not many road race tracks that will allow you to hit 200mph. Corner speed is what wins races especially when you have a lot of them. I use to run my old Kawi 750 turbo in the twisties and did quite well. Being that we are talking old school aircooled, it took about 20 minutes of hard riding to start hearing audible detonation and also feel the immense heat coming from the engine and turbo. It was geared for all 5 gears in the 1/4. It still had decent drive out of boost because of the ability to rev which in turn did not allow the bike to suddenly hit full boost like a light switch and possibly smoke the rear tire. It went through the powerband as if it was more linear. Even if you gear it a lot, your still going to make at least 200hp at the rear but it will be more controllable.

The other helpful solution is suitable sized turbo. Something that boosts quickly say by 3000rpms. It may be limited to 300hp maxed out but sometimes you have to sacrifice for whatever your goals are.

As I stated earlier about the heat generated by my old bike the other reason maybe because when road racing your usually hard on the bike for at least 15-20 minutes depending on the how many laps are in the race. Even though you are moving constantly and have airflow to the radiator and the rest of the bike, more heat is generated with a turbo and eventually the bike is going to be on ragged edge. This is where a A/A intercooler would be nice to have as far as keeping the possibility of detonation under some control for such a long period of time.

Well that is my 2 cents.

 

[BoostCreep]

There's a couple of factors going on here, for one '05 Busa LE' is correct, entry, exit, speed carried through, being smooth and having a pair is the best way to get around a track fast. I love the video I posted below simply because that little 250 is killing them around corners. The 600+ bikes shouldn't be falling that far behind but that driver on the little Kaw really is amazing.

NOW to continue, adding a turbo to a motorcycle adds to the difficulty of being smooth into, through and out of the corner. If you get a chance to drive an old turbo car, try to push it around corners and be gentle with the throttle, when it starts to get into boost, the intake pressures go up causing the exhaust pressure to automatically go up and you get this domino effect of dramatic power. I've road raced turbo cars (never bikes) and if I'm not running an anti-lag I will brake hard into the corner and at the right time floor it while continuing to brake which allows the boost to start to come up, around the apex where I feel the time is right I let off the brake as the boost is coming up and let off the gas and try to balance it in the right area so I maintain traction without sliding it (All that happens in a second). I end up destroying tires real fast, destroying brakes, the engine hates me, the turbo hates me, the pipes from the head to the turbo go under extreme heat.

If you need power like that you're probably in a race class where your spending more money than I care to explain. Most motorcycles are so light with such powerful engines, you simply do not need that sort of power. ON TOP OF THAT if you're racing more than just track days, you have to abide by the rules of the class your in, if you'd like to do a quick search of what those rules are you're more than welcome, but given the type of power these bikes have anyway I highly doubt turbos are allowed in almost any class (or you would see people doing it, trust me).

Am I forgetting anything?


Cliffs:

1. The power is not needed.
2. Unless your racing seriously, it's too expensive to keep up on.
3. The power itself is hard to control because of the way the boost comes on.

 

[Audiomaker]

Ok let's be specific here. What kind of power output are we talking? Stage I @ 240hp?

If your going to run a turbo on a road race course you have to treat it like it is NA. I would gear it similar to being NA. Rev quick and not as much load on the engine to create such a huge amount of TQ when in full boost. Street turbo bikes or cars excel at higher than normal speeds because typically they are geared like stock or less. There are not many road race tracks that will allow you to hit 200mph. Corner speed is what wins races especially when you have a lot of them. I use to run my old Kawi 750 turbo in the twisties and did quite well. Being that we are talking old school aircooled, it took about 20 minutes of hard riding to start hearing audible detonation and also feel the immense heat coming from the engine and turbo. It was geared for all 5 gears in the 1/4. It still had decent drive out of boost because of the ability to rev which in turn did not allow the bike to suddenly hit full boost like a light switch and possibly smoke the rear tire. It went through the powerband as if it was more linear. Even if you gear it a lot, your still going to make at least 200hp at the rear but it will be more controllable.

The other helpful solution is suitable sized turbo. Something that boosts quickly say by 3000rpms. It may be limited to 300hp maxed out but sometimes you have to sacrifice for whatever your goals are.

As I stated earlier about the heat generated by my old bike the other reason maybe because when road racing your usually hard on the bike for at least 15-20 minutes depending on the how many laps are in the race. Even though you are moving constantly and have airflow to the radiator and the rest of the bike, more heat is generated with a turbo and eventually the bike is going to be on ragged edge. This is where a A/A intercooler would be nice to have as far as keeping the possibility of detonation under some control for such a long period of time.

Well that is my 2 cents.

Well that makes sense too... the heat and duty cycle. Yes, I was speaking of turbo's in the 240hp range...streetable ones with a SWB. Lots of turns...need a bike lighter and set up specifically for turns...makes sense too.
On the other hand, that doesn't explain the almost complete lack of turbo's I've seen in track vid's. I mean nobody is going out there with them?
I mean figure the bike weighs a bit more (but so can some riders), but they can still turn well enough to go have fun on the track no? It's just like they don't exist except on the street. Certainly there are lots of bikes that go to the track that would perform worse, but they still go. Boost can be turned down as far as I've read.

I start to wonder if it's more a mental thing...or?

 

[Audiomaker]

Kook...another awesome explanation.

I think it's all clear to me now

Sean

 

[megawatt]

....who cares about 35lbs or so when the stock exhaust weighs a ton. ....

True but the turbo hangs off the front and the stock exhaust system is heaviest to the rear of the bike. The original weight distribution when the bike was made had the heavy exhaust in the back, move that weight to the front and the bike handles much different on the track.

....NOW to continue, adding a turbo to a motorcycle adds to the difficulty of being smooth into, through and out of the corner.

....3. The power itself is hard to control because of the way the boost comes on.

With all respect, my turbo busa is super smooth on power delivery, totally predictable, and with the short lengths of plumbing there is no turbo lag. I have no problem riding around in corner on & off boost. I do experience turbo lag in my car but not on my bike. I totally agree when you say the power of a turbo is not needed for a road course application when you have todays engine power outputs on a NA engine.

 

[dadofthree]

55,000 posts? How did you even have time to be a dad of 1 ?

My children had finished high school by time I joined. Feel free to ask my kids. I was always there. Probably the best 25 years of my life.

 

[Busashot]

A typical Stage I turbo kit with just dump pipe weighs about the same as the stock exhaust maybe a few lbs. more. Stock exhaust is 31lbs. 6oz. I use a 50lb calibrated fish scale and have weighed 2 complete stock exhausts and that is what they weigh, simple. As far as weight in the front of the bike, well yea your going to notice slightly heavier steering. But consider this, most of the weight of the turbo kit is at the lower part of the bike. Not a big deal IMHO. The stock header weighs 10lbs 10oz. So you could say that you only gained about 20-25lbs in the front of the bike. If you want to compensate for this change just mess with the suspension and take the steering stabilizer off. It will almost feel like stock again......

 

[Tufbusa]

It's not just the busa, there are no turbo bikes within the road racing world of club racing nor professional racing.

 

[moloko]

If you want to do track days that money is better spent on some bst wheels.