Roadracing World – April 2019

By Michael Gougis

D

on't let the stock tires on

your sportbike stop you

from doing your fi rst track

day. You'll typically be way too

busy getting used to the new envi-

ronment to worry about 10-10ths

performance from your tires. And

stock tires are plenty good enough

to generate the kind of lean angles

that you see in the photos pub-

lished in Roadracing World from

new model introductions.

But eventually the stock tires

will wear out. And fortunately,

this is 2019, and there is a wide

range of higher-performing tires

that will allow you to ride hard-

er, with more lean angle and with

more confi dence than the stock

tires provide.

The biggest question facing

you, realistically, is: Track day

tires, or race tires?

Sometimes circumstances

dictate the answer. If you're using

your motorcycle on the street, rac-

ing slicks are out. It's not just ille-

gal to use non DOT-approved tires

on the street, it's not smart. Slicks

generally require consistent hard

use to stay within their optimal

operating temperature range, and

when they fall out of that range,

they don't stick as well. And one

unexpected wet stretch of road

or strip of water run-off coursing

through the apex of a corner can

mean a disastrous end to your

weekend morning ride. Honestly,

if you're riding hard enough to re-

quire racing slicks on the street,

it's probably time to re-assess

your street riding.

If you are riding on the street,

there are plenty of DOT-labeled

tires that are far stickier than

the tires that came stock on your

machine. Performance-oriented

companies often make a range of

street-legal tires that offer differ-

ing amounts of grip to match the

use of your bike.

If you are riding only on

the track, your have the choice

of track-oriented treaded tires or

slicks. DOT-labeled racing tires

may have a tread pattern, but it's

best to treat them like full racing

tires. And that means tire warm-

ers, stands front and rear, and a

source of power for the warmers.

Same thing with the major-

ity of slicks; they're high-perfor-

mance products, and they take

more care and feeding.

The benefi t is that if you use

them properly and can ride them

well, slicks provide more grip and

feel than any treaded tire can. Af-

ter all, the primary purpose of a

tread pattern is to move water aw-

way from the contact patch, and

prevent hydroplaning. When it's

dry, a slick produces more grip.

More grip means more confi -

dence and more fun. And because

they use racing compounds, a

properly-operated DOT-labeled

race tire can come pretty close to

the feel of a full racing slick.

Even if you’re not on a full-

size sportbike, the experience of

riding on slicks is now available to

you. As the smaller-displacement

sportbike race classes grow in

popularity, tire manufacturers are

taking the classes more seriously.

Dunlop is providing slick tires for

the MotoAmerica Liqui Moly Junior

Cup class in 2019, and Pirelli also

has introduced a range of slicks

specifi cally for the 300cc-400cc

lightweight sportbike category.

New track-oriented tires do

not require using tire warmers,

and some offer construction fea-

tures that come straight from the

professional racing department.

Racing Editor Chris Ulrich

had the opportunity to ride the

KTM 790 Duke at Auto Club

Speedway with its stock street

tires and again a few months lat-

er, in February, at the same track

with a set of Sportmax Dunlop Q4

mounted on the rims.

"The big difference is grip!"

Ulrich says. "At the rear, from the

fi rst touch of the throttle until the

drive out, the stock tires would

spin. The Dunlop Q4s, the edge

grip was better in the middle of

the corner, and in the acceleration

zone, they dug in and pushed the

bike forward. It was so much so

that I had to change a few things

up at the apex, because with the

additional grip the bike wanted

to push wide. They stuck, rather

than spinning,s and actually help-

ing fi nish the corner.

"With the stock tires, I would

start to lose the front early. I could

trail the brakes into the corner,

but there wasn't the grip. With

the Q4, I could brake a lot later

and trail the bike in with a lot

more pressure on the lever. The

bike was more stable, and overall I

could go a lot faster."

What is most remarkable is

that when Ulrich rode the bike

with the Q4s, conditions were far

from optimal. The track had been

drenched by a solid, steady rain

in the morning, and the surface

was still chilly and damp when

Ulrich headed out on the 790

Duke equipped with the Dunlop

Q4 tires. "Even in the tricky con-

ditions, the tire came up to tem-

perature a lot more quickly than

a slick would, even if the slick was

on warmers, and held the tem-

perature a lot better," Ulrich says.

At the introduction of the Q4

tire, former Superbike racer turned

Dunlop tire tester Taylor Knapp

Racing Editor Chris Ulrich found that the stock tires were the limiting factor on the KTM 790 Duke on the track.

With a set of sticky Dunlop Q4 tires mounted, the fun was greatly amplifi ed. Photo by caliphotography.com.

A Michelin Power Performance Cup

rear tire designed for track day use.

36—Roadracing World, Trackday Directory 2019

Which To

Choose?

TRACK DAY TIRES VS. RACING TIRES: