| Author |
Message |
    
José_quiñones
| | Posted on Friday, March 05, 2004 - 06:04 pm: | 
|
Not Horsepower (and FX bikes don't make 150hp,SS bikes don't make 130 hp) it's the Tires, as explained in amasuperbike.com
quote:Too Much Tire?
honda fx bikes using superbike rubber
by evan williams
Thursday, March 04, 2004
What's the deal with Formula Xtreme? Pole time for Supersport was Jason DiSalvo's 1:50.998 on a Yamaha R6. Honda's Ben Bostrom earned pole in FX with a 1:52.800. The FX bikes have more power, weigh less, and have better suspensions and brakes, yet are slower than the Supersport bikes at Daytona.
Amazingly, the riders are complaining of having too much rear tire.
According to the riders and technicians, the Honda FX bikes are sporting 6 inch wide, 16.5 diameter wheels and last year's Dunlop Superbike tire at Daytona. It seems the riders feel the big Superbike rubber might not be ideal for lap times. Not only the tire is difficult to break loose, which is the fast way around the track, but the tires and wheels are too heavy for the lighter 600.
"It's way more tire than we need," Jake Zemke said.
Honda was presented with choosing 17 or 16.5 inch tires by Dunlop. Honda chose to try last year's Superbike tires, as the team had experience with them and wheels left over from the RC51s. After testing and now racing, it seems they made the wrong choice. Those are the perils of a new racing class where the boundaries are relatively unexplored. Honda said finding those limits was one of the reasons they chose the FX route.
Still, Honda looks to be doing very well in the reborn Formula Xtreme, with four of the top six qualifiers.
ENDS
|
Blake
| | Posted on Friday, March 05, 2004 - 07:14 pm: |
|
That is really interesting. Certainly shows that tire choice can play a HUGE role in lap times. Probably won't keep us from continuing to compare lap times though. 
For someone who REALLY does NOT know, you sure are confident about the performance levels of factory SS and FX racing machines.  |
Blake
| | Posted on Friday, March 05, 2004 - 07:46 pm: |
|
Hey Marcus,
Do you have any idea what kind of power the leading factory Supersport machines are making? I remember John Haner telling me during a rained out practice day at OHR once last Summer, that he could keep up with the factory guys through the curves even gain a little, but when they got to the high speed straights they would walk away from him. He has lost about 30 LBs since then. |
Marcus_mcbain
| | Posted on Friday, March 05, 2004 - 10:57 pm: |
|
Generally Speaking,
The HP numbers from Privateer to Factory rider is not significant. The Yosh and HRC bikes are probably at 120bhp on the 600's now, BUT how they make that power is significant. There are three things that the factory guys (and top privateers) do/have that make the big difference:
1) Optimal Cam timing - Everyone knows that if you advance the ignition, the motorcycle will accelerate quicker. Because most riders don't go to tracks like Daytona, advancing the ignition is usually a bad idea relative to performance at tracks like Daytona. As much improvement that is experienced in acceleration, an equal amount performance is lost by virtue of no acceleration at sustained RPM's. This is the number one cause of why the 114bhp privateer bike get's walked by the 118bhp factory bike. By retarding the cams/timing the bike pulls exceptionally well at HIGH RPM.
2) Torque - In combination with cam timing, tuners will utilize overbore rules to a maximum to gain torque that provides better "drive" off the turns. This happens A LOT in F-USA. Many bikes are bored to 650cc's-700cc's and have the compression LOWERED. The goal is to gain enough HP, but stay under the HP limit WHILE GAINING SIGNIFICANT TORQUE.
3) Yeah, there are some parts the factory guys get that no one else really has access to.
Marcus |
José_quiñones
| | Posted on Saturday, March 06, 2004 - 02:55 pm: |
|
quote:The HP numbers from Privateer to Factory rider is not significant.
As Michael Barnes just proved on a self-confessed "Bone-Stock" Yamaha R6
For someone who REALLY does NOT know, I'm pretty close. That's what happens when you read the RULEBOOK. |
Marcus_mcbain
| | Posted on Saturday, March 06, 2004 - 04:21 pm: |
|
It is easy to read a lot into "bone stock", but I guarantee it is NOT.
It may have stock valves, ports, etc. The fact it could pull in the draft of the other bikes tells me that something with the ignition/cam timing has been altered. That is why if you look at F-USA results where it is HP constricted, the 10th place guy that made 110bhp got his butt stomped on the banking by the guy in 3rd place who only is making 106.5bhp. (Hypothetical situation, but you can lookup results and see for yourself).
Marcus |
Anonymous
| | Posted on Saturday, March 06, 2004 - 11:07 pm: |
|
Marcus, don't bother to argue with a professional like Jose...a professional arguer, that is... The stuff that comes out of him is absurd, but that's the way he is. The good news is, we aren't him! It must be awful to go around trying to make people believe you know everything, when it's obvious you don't... |
Blake
| | Posted on Saturday, March 06, 2004 - 11:30 pm: |
|
Thanks for clarifying the issue Marcus. Interesting. I'd not thought about powerband other than peak HP. Strange since I'm all about good power delivery ALL over.
You know what still fries my brain though. The lead Superbikes were often running 1:50's and higher during the race. I would have never expected, on a high speed track like Daytona, that the 600cc Supersport qualification lap time for pole position would penetrate the Superbike racing lap times. I guess even at Daytona, it's corner speed, corner speed, corner speed. I just have trouble wrapping my brain around the fact that even with gummy ole qualifying tires a 120rwhp SS can make a lap that would put it in the lead pack during the Superbike race.
Bummer for EBoz, Ducati, and Michelin. 
Haner did well. And who would have guessed, a privateer in 4th place! Too cool. Until you realize that three of six factory entries DNF'd.
Yates should be fired, fined, and suspended for the season. What a childish jerk. |
Benm2
| | Posted on Sunday, March 07, 2004 - 08:42 am: |
|
Maybe the track's the speed limit at Daytona, the infield offers no advantage to the superbikes, and the big bikes can't take advantage of the banking due to poor track surface & tire loads. The new Daytona Dunlops were probably Cheng Shin hard & heavy. Or, maybe the SS riders are just faster... |
José_quiñones
| | Posted on Sunday, March 07, 2004 - 10:36 am: |
|
Marcus,
I fully understand that Michael's bike, which he himself described as "box stock", is tuned, as much as the rules allow.
But since the performance difference is not "significant" as you mentioned, he's a good enough rider to make up the difference between him and a full factory Yamaha Bike. The fact that he was on Pirellis makes it even more interesting.
But as you said, they make horsepower in the 120 hp range, not 130's, a myth that that Blake has repeatedly tried to spread on this and other boards.
_____________________________
Superbike tires have to last at least 19 laps at Daytona. The Supersport race is 18 laps and the bikes make less power and weigh less.
So the DOT tires they use actually have more traction than Superbike tires at Daytona. This is the reason that the FX bikes were slower, they were using the harder Superbike tires on 16.5 superbike wheels instead of the grippier DOT race tires on 17 inch wheels. |
Dynarider
| | Posted on Sunday, March 07, 2004 - 11:43 am: |
|
But since the performance difference is not "significant" as you mentioned, he's a good enough rider to make up the difference between him and a full factory Yamaha Bike.
I could go with that. Im pretty sure...not positive tho...that in racing you have good riders & you have great riders, just like we do out on the street. Even tho these guys may be racing at the professional level im sure some are simply better at it & able to get more out of a lesser bike.
Us mere mortals wouldnt even keep up with the back markers in these races no matter what bike we were on. |
Blake
| | Posted on Sunday, March 07, 2004 - 02:39 pm: |
|
JQ,
What the hell are you talking about? Mladin the SBK race winner pitted three times for tires, an average of 15 laps per tire. And I was referring to the Supersport pole position qualifying lap versus the SBK race lap times. The SS race laps were nowhere near that of the Superbikes. The Superbike pole was earned by Eric Bostrom on the Ducati 999R with a 1:46, about 4 seconds quicker than the pole winning time for Supersport. I was simply offering that while I knew that tires are crucial to lap time performance, I had no idea they could make THAT much of a difference (4 seconds between qualifier tire and race tire).
As far as my belief in the "myth" of 130 rwhp factory Supersport machines. It seems I am wrong on that. Congratulations. So it's not the peak HP but the improved overall powerband performance that give the facotry machines an edge. The effect is the same. The factory bikes are not on par with any "box stock" machine, which is what you have contended. Rather the factory racing machines are greatly enhanced in their power delivery over the useful racing rev range. They have a lot more power at 8,000 through 16,000 rpm than a typical privateer's race prepped supersport machine.
And again, congratulations on witnessing the exposure of my mistaken "130 rwhp" opinion. I know that means a lot to you.
I certainly am thankful to Marcus for taking time to explain the issue. It is very interesting and informative. It is unfortunate that you find it necessary to distort his statements. I guess the argument for you is more important than the truth.
Marcus says "The HP numbers from Privateer to Factory rider is not significant." And by "HP" he clearly meant peak HP as that is what we were discussing.
But you interpret his statement as meaning "the performance difference is not 'significant'." 
edited by blake on March 07, 2004 |
Marcus_mcbain
| | Posted on Sunday, March 07, 2004 - 05:07 pm: |
|
I am more than sure that shortly, you will see kits and FX bikes make 130+ bhp, BUT the obvious situation where the riders said they cannot get the back end slide, tells me that they are still under 120bhp.
I think the manufacturers will learn A LOT over the next year. Honda, Kawasaki, and Yamaha should have a head start on this class since their bikes are not "new".
Should be fun to watch.
Marcus |
José_quiñones
| | Posted on Thursday, March 11, 2004 - 06:58 pm: |
|
Blake,
I have no disagreement with Marcus at all, and Michael Barnes' performance in the Supersport race proves him right.
I WAS referring to "peak Hp" when I said "performance differences " because that's what we were talking about, peak HP numbers, or as you phrased it yourself "performance levels", wasn't that clear? The area under the curve is a whole different topic.
About the tires I was responding to Ben when he asked if the track was the limiting factor, to which I say yes, you can see it in the FX times compared to the SS times, sorry I did not address it to him directly.
So, in summary, AMA SS Factory bikes don't make 130 HP, and the FX Factory Bikes don't make 150 HP. They make less.
Buell does not need to get to 150 hp, 138 like they have already is fine. They do need to get the bike down to 350 pounds.
edited by josé_quiñones on March 11, 2004 |
Blake
| | Posted on Thursday, March 11, 2004 - 11:40 pm: |
|
Just read the article in RRW by young Nicky Wimbauer about his tryout with a German Yamaha World Supersport team. Great article! Some interesting info in there about the team's R6 SS racing machine... 140 rwhp, revving to 17,000 rpm and still pulling...
That's impressive. The stock redline for an R6 is 15,500 rpm and RRW reports the R6's peak HP right at 102 rwhp and 12,500 rpm. 
|
José_quiñones
| | Posted on Friday, March 12, 2004 - 07:02 am: |
|
Different rules, different "performance levels" |
|
