From July 16 yrs ago.
Run Rear Tire on Front
By Jim Smith (Floridajim) on Wednesday, July 12, 2000 - 08:30 am:
And now time for something completly different! I am running Dunlop 491 elite-2's on my valk. The rear is a 160/80/16 same size as comes on the wing the front is a MT90/17 a rear tire I am running backwards for safety reasons. The current rear tire is my second time around with this model tire. I got 11,600 miles with the first one with 1/32's tread remaining when I changed out I run 41 psi. At 5,600 miles on this one I have 6/32's of tread left so I should get around the same again (if I can stop snatching 2nd, trigger wheel makes me do it!).The elite front at the same 5,600 miles has used exactly 1/32 of rubber running 36psi for handeling reasons, so it will probably dryrot before I wear it out(at current wear 50,000 + Miles??) It currently has 10/32's of tread left. I drive mostly single and moderately fast with ½ city & ½ country driving in South coastal Fla. so there isn't a lot of twisties. The current set up is handling very well, not as sticky as the stock but I don't ride in any road races or try to tame mountain roads either, I do scrape the running boards at speed on a regular basis on my favorite road and have never been fearful the tires would break loose in a hard curve. There is also no tread noise as with the stock tires. This set up is more than fine for my capabilities and road conditions. Just my experience. Your milage of course "will" vary due to different riding style and road conditions. Jim (-=
--------------------------------------------------------------------------------
By don r. tyler (Txduke) on Wednesday, July 12, 2000 - 06:05 pm:
do what......running a rear wing tire backwards on the front of the valkyrie? i thought all motorcycle tires were directional......what is the safety reason for this ? please let me know!
me dont understand......thanks
--------------------------------------------------------------------------------
By Jim Smith (Floridajim) on Thursday, July 13, 2000 - 08:16 am:
This is a long answer to a short question. But you asked.Posted by Fla. Jim on Wed - Apr 26 - 09:51am:
Dunlop was no help at all (go figure!!) so I went to my local tire company that has always answered straight questions with straight answers. Here is my question and their reply.
-----Original Message-----
From:
Smithjos@aol.com Sent: Tuesday, April 25, 2000 3:09 PM
To:
Subject: Useing rear tire on front
Hello: I am currently using a rear tire on the front of my bike. I have heard a lot of disclaimers and read a lot more about why not to do this so I understand you can't condone this practice. I also understand this was quite a common practice some years back when front and rear tires were the same size. It seems back then whenever they did this they turned the rear tire backwards, with the logic being that the rear was designed to push not brake? Since I now have over 3,000 mile of stop and go running with multiple hard stops and no problems to date can you think of a reason I should turn the tire backwards? The tire in Question is not of your manufacture and I promise to keep the "****" name out of any correspondense I may have with other bikers. I will continue to run the rear on the front no matter what your reply. I am just courious as to the "best" rotation to run it. Your Company has always been straight up in answering my questions, so in advance I thank you for your reply. Jim Smith, South Florida
========================================
Hi Jim
Yes you should turn the tyre around, to run against its direction arrows. This is because of the way the tread joint is made on the tyre. When braking the forces generated will try to open the tread jointing of the tyre. This will be prevented if the tyre is run in reverse direction
========================================
Hi again, Thanks for your prompt reply. Not knowing proper tire manufacture terminology I am somewhat confused with your reply. "This is because of the way the tread joint is made on the tyre. When braking the forces generated will try to open the tread jointing of the tyre." By tread joint are you referring to the tread pattern, or the way the belts are laid under the tread? Thanks again Jim Smith
----------------------------------------
Hi jim
Please excuse me. The tread is applied to a tyre as a flat wide strip of rubber. When moulded the pattern is added. The ends of the tread obviously have to be joined together prior to moulding. The ends of the tread are not butt jointed together, but cut at a steep angle & then joined together. This obviously makes the joint area larger to help absorb the stress placed upon it. Therefore because they are joined at an angle, if you rotate the tyre in one direction you will (in effect) close the joint once every rotation. If you rotate it in the other direction you will try to open the joint once every rotation. A rear tyre is arrowed to close the joint on every rotation of the tyre as it is put under power.
The same tyre would have to be mounted against its rotation arrow on the frontbecause although in normal use the joint is runnng the wrong way, there is no force being applied to it (the front wheel is just running along without the application of power). however when you brake, a strong force is pushing from the rear to the front of the motorcycle, & this would open up the tead joint, possibly leading to the tread shearing off the tyre completely. Therefore, if you run the rear tyre backwards on the front, braking forces will then be trying to close the tread joint, overall the best situation. Its a little complicated, I know. To follow it better use an orange, a pen & a chees grater. With the pen draw a slight arc on the orange, and imagine this to be the tread joint. rotate this as a rear tyre & press the grater into the bottom of it, forcing it backwards. Now do the same again but turn the grater around. The first time that you do it, you will see the scar from the grater is the same angle as the curve. The second time the grater mark will curve the wrong way. Therefore to use this orange as a front tyre (but still get the grater mark to be the same, you have to turn the orange around
I hope this has been of use to you.
