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Discussion Starter · #1 ·
Guess I've been doing it wrong all these years? :eek: :dontknow:

Complete article here: http://www.rattlebars.com/valkfaq/tirewear/index.html

REAR CENTER TIRE WEAR:
But if it's only the extra miles that cause the wear, wouldn't the center if my tire wear out first since I have more miles upright than leaned? Yes and some upright wear is evident upon inspection of a worn front tire as seen in the photo above left. Though this wear is not as excessive up front as the sidewall wear because of one factor... Upright miles on a properly inflated front tire are rolling miles with little scuffing taking place. If, on the other hand, you look at your rear tire, you will indeed see that the center wears out first and this wear is often exaggerated because acceleration, engine braking* and real braking scuff stuff off the upright rear tire. Each time you downshift to engine brake, upshift and release the clutch, roll on the throttle or roll off the throttle, you will scuff the rear tire at the contact patch. Along with that, the rear is your drive tire and at speed, the rear contact patch is the only thing that keeps you going (don't believe it? Just let off the throttle and see how quickly your bike slows to a stop!). Since most acceleration/deceleration and braking occurs when the bike is more or less straight up this wear is most evident in the center of the rear tire. Drive shaft bikes are the worst offenders since they are notably "herky jerky" and transfer the shock of accel/decel directly to the rear contact patch unbuffered. Belt and chain drives will "buffer" these shocks and lessen this kind of wear. This same scuffing action is minimal on the front tire because the front tire is undriven and merely rolls while the rear tire is doing all the inertial work. When brakes are applied, traction at the front tire improves minimizing scuffing while traction at the rear tire deteriorates maximizing scuffing.
* Engine braking is the exercise of downshifting and releasing the clutch through all the gears when coming to a stop. On most modern bikes equipped with disc brakes this old timer's use of the engine to aid in braking is totally unnecessary. Doing so will loose you thousands of serviceable miles on your rear tire, will double the stress on your drive train and could cause your rear wheel to lock (even on a bike with ABS) causing a crash. When coming to a normal stop (red light etc) downshifting commensurate with your speed is still essential to bike safety (in case you need to power out of a jam), but releasing the clutch when doing so is not necessary and adds greatly rear tire flat band center wear. Keep that clutch pulled.
 

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wow great info....

never thought of it that in depth
 

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"Engine braking is the exercise of downshifting and releasing the clutch through all the gears when coming to a stop. On most modern bikes equipped with disc brakes this old timer's use of the engine to aid in braking is totally unnecessary."

Wow.....Guess thats why I'm coming up on 10,000 miles on my E-3s( should get another 5K at least ), still on the original brake pads at 17,000+miles, and have more wear on the FRONT tire than the rear. Yep....downshifting MUST be my problem.

Now, I don't E-brake thru all the gears, but most.

HEY EY3LESS.....I MADE IT...I'M AN "OLD-TIMER" :D
 

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Very good info! Now, getting rid of the habit is another "thread"...
Thanks for the article!:bigthumbsup:
 

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Wanna know how to engine-brake downshift properly, without "killing" your rear tire? Ask a truck driver how we downshift without using the clutch. :bigthumbsup:
 

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Discussion Starter · #7 ·
On my new Elite3 that I'm getting ready to put on, I'm going to concentrate on downshifting, but only when the bike is leaned one way or the other. :D

Then, if the article is correct, the sides of the rear tire will then wear consistently with the center.
 

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Wanna know how to engine-brake downshift properly, without "killing" your rear tire? Ask a truck driver how we downshift without using the clutch. :bigthumbsup:
Float those gear up and down. rev it up and drop it in.
 

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:bigthumbsup::agree: Been driving trucks for about 12 yrs now.
Float those gear up and down. rev it up and drop it in.
Quote:
Originally Posted by MarlboroLts
Wanna know how to engine-brake downshift properly, without "killing" your rear tire? Ask a truck driver how we downshift without using the clutch. :bigthumbsup:
 

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:bigthumbsup::agree: Been driving trucks for about 12 yrs now.
Quote:
Originally Posted by MarlboroLts
Wanna know how to engine-brake downshift properly, without "killing" your rear tire? Ask a truck driver how we downshift without using the clutch. :bigthumbsup:
Did it for 10 before I joined the Navy.....at 30. Damn, I guess I really am an "Old-Timer". :eek: :bigthumbsup:
 

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I agree with that 100%. I wish I had taken pictures of the stock rear tire on mine when I took it off at 5200 miles. It had "feathers" of rubber extending off the edge of the tread blocks, and some were long enough to almost cover the grooves in the tread. It was all from downshifting. Being new and the bike sounding so good doing it, I did it at every opportunity. The next tire got almost 12,000 miles on it and had none of the feathering.
 

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Love 2 Downshift

:agree: With the article also...But premature tire ware or not Im not about 2 stop down shifting my Nine...or any bike 4 that matter.
I have well over 20 years experience as commercial driver[Big Rigs/TRAC TRLR] the only time I would use the clutch is from a dead stop & a start, they are designed 2B operated as such... but I would not recommend [especially down shifting] the M109's without the clutch...not that i've never done it:bigthumbsup:
 

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I'd never agree with trying to downshift without using the clutch. But I've met many riders that downshift without bringing the RPMs up....they just let the clutch out and let the clutch and tranny do the work bringing the engine RPMs up. Thats where the tire wear is coming from.

Just looked at my rear tire...almost 10K....no scuffs or wear of any kind like the article is talking about.
 

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I can see where it can cause premature wear if you just dump the clutch
on a down shift. You need to blip the throttle before you let out the
clutch. What you want to avoid is a shudder from the driveline and a
squealing the rear tire.
 
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