Bonneville Motorcycle tires-What are we gonna' d

[TZ750]

What are we going to use for tires on our REALLY fast motorcycles?

Our rules do NOT give 50 MPH addition to "Z" rated tires. The rules give the 50 MPH to EITHER "V" rated tires, or to Road Race tires.

That means that ONLY SHAVED ROAD RACE TIRES are "good" for OVER 200 MPH. Think about it.

It also means that there are NO motorcycle tires in modern sizes that are certified for over 250 MPH, period.

I have personal opinions about this, but I am not a tire manufacturering expert, and I have NO official opinion about what is safe at about 250 MPH. But let me say this.......

In Road Race tire tests at Daytona last fall, Dunlop Superbike [roadrace] tires (more than one) came apart at speeds considerably less than 200 MPH. In one case, a nationally ranked professional racer was put on the pavement HARD at about 185 MPH, and was seriously injured.

If there is one form of racing that uses our type of tires, and is important to the tire manufacturers, it is MotoGP.

It is not land speed racing.

In recent testing, Bridgestone had problems with tire seperations in MotoGP trsting at the Sepang circuit in Malaysia. Injured was none less than former world champion Kenny Roberts, Jr.

Bridgestone is to be congratulated for so quickly catching up with Dunlop. (See Michael Scott's article on page 87 of the 3/3/4 issue of CYCLE NEWS, which I so shamelessly quote)

If the manufacturers can't make a road race tire reliable for 200 MPH when money is no object, do you really think that they will "certify" that same tire (maybe "shaved") for 250 MPH or over? I've got this bridge for sale......

How much horsepower do USA Superbikes make? Not that much, compared with Turbo Hayabusa's, which are now showing over 500 HP on dyno's. How fast are MotoGP bikes? Nothing like Rich Yancy's 250 MPH street Hayabusa.

If the some of the world's most prominant motorcycle tire manufacturers, with as close to an unlimited budget for tire developement as the motorcycle world can have, can't make tires reliably safe at "only" 200 MPH, how can we expect to have complete safety at 250 MPH?

Remember, kinetic energy goes up as the SQUARE of the speed!

If these same manufacturers are having problems with their best tires, on the world's biggest stage, with the world's biggest audiences, what can WE expect?

The job can be done, and done right. When Don Vesco set the World Speed record of 318.598 MPH in 1978, he did so on tires that I supplied to him. These Goodyear tires were manufactured in 1974 for motorcycle land speed racing. At the time of the record, these tires had a LOT of miles on them, were four years old, and were supporting a HEAVY twin engine, fully streamelined motorcycle.

Those were special, designed-for-bonneville tires. Small by today's standards, I remember them as something like 3.50 x 18 of 19. Old schooln for sure, but designed for the job.

Ride carefully, my friends

 

[PaceMaster]

I am no expert..but safety at Bonneville with ZR rated tires [might] be safe as [heat] is not a problem....you tell me...very curious....who does know about tire temps on the salt...Landspeed Larry..266 mph..woohoo..any info??

 

[Franklin]

The Burklands have a tire spin testing machine. Talk to them about testing a selection of tires to establish a baseline so you'll know where you really stand.

 

[Landspeed Larry]

High speed tires for Bonneville motorcycles are such a special category that no manufacturer will make or certify such tires. Roadrace slicks are not a good choice as their soft, flexible carcass is designed for adhesion while leaning the bike. Daytona's banking puts extreme centrifical forces on those tires which could be made safe by increasing the rubber hardness and cord stiffness. Neither factor contributes to low lap times. The Z-rated street radials have extra cord for durability at DOT mandated test standards. When the extra rubber is shaved off for Bonneville (to prevent head buildup), they become the best current choice. The Bonneville inspectors are checking the very fast bikes after each run for signs of wear etc. At present, this is the best we can do.I don't expect current turbo "streetbikes" to go much over 250. That said, I do expect my custom Busa special called Project 260 to go that fast. We screw the beads to the rims and monitor the the pressures carefully. When you are at the performance edge, all bets carry risks. LSL

 

[TZ750]

Land Speed Larry is correct about everything he says.

Perhaps to the point is that the bikes running 240 MPH plus on "street" Radials are doing it against the Bonneville rules. The fact that the inspectors allow SOME riders to "experiment" is another question.

I would hate to be one of the people that spends a lot of time and a lot of money to go to Bonneville to be told "Sorry, your tires do not meet the rules. You have to get acceptable tires or go home."

They have done it to me, they have done it to Carl Morrow (Harley national drags race championship team), they could do it to anyone else.

Are YOU willing to take the chance?

 

[Franklin]

In 1960, there was no Mickey Thompson tire company. Mickey ran Challenger I on GOODYEAR tires. Yet the letter below is posted on the www.scta-bni.org website.

"October 31, 2003

To: Roy Creel , President of SCTA and Users of Mickey Thompson Bonneville Tires

For over 3 decades, Mickey Thompson Tires has supplied Land Speed Record (LSR) tires for runs over 300 MPH. The technology put forth in these tires is a result of many years of R&D, dating back to 1960 when Mickey Thompson himself made a historic run of 409 miles per hour. Today, Don Vesco holds the current record of 427 miles per hour, both records set on Mickey Thompson LSR Tires.

As many of you know, Mickey Thompson (M/T) did not have its own factory and thus outsourced the production of these tires until the end of 2001. Since that time, we have actively pursued a new source of supply with regrettably no success. We truly understand the important role that M/T high-speed tires play for you to achieve your monumental goals and advance the sport. We apologize for any inconveniences this disruption in supply may have caused you. Our goal is simple - to supply the same great quality and performance that each of you has come to expect from Mickey Thompson LSR Tires.

We greatly appreciate your understanding and patience as we strive to resolve this issue and we will update the LSR Community as new developments materialize.

Ken Warner

VP Sales and Marketing

Mickey Thompson Tires"