Tires Swapping, Mismatch?

[FJReady]

Nice new place here.

I don't intend to start a tire thread but I would like to know if anyone has put an Avon A46 on the rear while keeping the worn but not worn out OEM 'stone on the front.

It appears that I'll get maybe 8 to 10K out of the front but the rear is pretty much gone at 7K.

Comments welcome.

I didn't see a section here under Technical for tire or oil related topics. I wonder if the popularity of those topics might earn their own categories?

Thanks,

FJReady

 

[super d]

As long as they are both radials ....why the hell not!!! I'm going to! :bleh:

 

[radman]

I was gonna stay with the oe stone while replacing the worn rear, but the cupping on the stone induces a vibration in the bars that only gets worse as the miles roll on. I did 'em both.

 

[Vstar2FJR]

I did exactly that on my 05 at 8000 miles, replaced the rear stone with the Avon, left the front stone on. Only did it for 500 miles because of an upcoming long trip, but I experienced no negative affects that were noticeable to me in the drivers seat. Unfortunately, I have absolutely NO SCIENTIFIC OR ENGINEERING back up for this statement . If your stone is still good, use it up!

Sorry BrunDog, couldn't resist! See https://www.fjrforum.com/forum//index.php?showtopic=411

 

[markjenn]

No big deal, but I view it as false economy. That "worn but not worn out" front is going to handle like crap until you replace it. Trying to get that extra 1/3 of tread life that a front will outlast a rear is just not worth it, IMHO. If you could get one front to last two rears, I might give it a try, but the front almost never goes 2x the rear.

- Mark

 

[FJReady]

MarkJenn,

I've read alot of your posts and generally their spot on and based on sound thinking. So I want to understand your reply about the tire question. I may be missing something. I don't see that leaving the front tire on longer is a false economy. I get no savings by changing them together. So I can't see the value in the front tire life being a whole multiple of the rear(hope thats clear). My front isn't cupping or showing any other weird behavior so I see no reason to toss it out with several more usable miles on it. What is going to make it handle like crap with a new rear if it isn't handling like crap now? I'm not picking a fight or challenging your logic, Just want to understand if I'm missing something.

Thanks, appreciate any response.

Hope all have a good and safe holiday weekend.

 

[markjenn]

Ready, if you are happy with the way your bike is handling with the worn front tire and anticpate you'd be happy until it hits the wear bars, then obviously you're right - no reason to take it off.

But I have a story to tell. Five years ago, a bunch of us went to Europe on an Edelweiss tour and all had identical R1100S bikes. One had a half-worn front tire and new rear tire; the rest of us had new tires front/rear. We started riding and the guy with the worn front tire started complaining that his bike was handling poorly. I didn't think it was a big deal UNTIL I traded bikes. I'm not kidding, on the first corner, I came with a whisker of running the bike into the ditch. The next day we got a new tire and the bike's great handling reappeared.

I think a lot of riders don't notice how the handling has deteoriated until they get the new tire. I'd bet you a dollar to a donut that if you went out today and put a new Avon on the front, you'd come back from your first ride saying that the bike handles much better.

With a worn front tire, the most common problem that develops is cronic understeer, such that you have to continually hold inside bar pressure to keep from running wide. The second problem is "bump steer" where if you hit a bump while leaned over, the bike will wobble.

My comment about the "2x" is simply that if you're replacing tires willy-nilly front/rear as they indivdually wear, then you're changing tires a lot more often because you're only replacing one at a time rather than pairs. If the front would go 2x the rear, then you could get into a rhythm where you simply replace the rear 2x the front.

So to summarize, with a front tire running $90, getting that last $30 worth of tread out of the front just isn't worth the poor handling and odd cycle of tire changes. For an additional $30 every 5K miles, I think it is a good tradeoff to simply replace them both and enjoy brand new, matched tires front/rear.

YMMV.

- Mark

 

[radman]

Took Frank on it's first good wring out since puttin the Avons on. Broke them in on the twisties near my home. First off, I'm certain I made the right decision replacing both tires at the same time. Frank rides like new again, and thats no bull. I put about 60 miles on the tires before hittin the twisties, and he was smooth as butter. Stone vibes were gone. Hit the twisties, takin it easy till the sidewalls got some scuff. First the 45's (mph) at 60 or so. A little slippy, but not bad. By the time I got to the 35's, I was able once again to roughly double the posted speed on entry. By the end of this afternoons ride, I was able to haul into the turns with complete confidence that I'd live to write this, something the Stones had become incapable of doing. I believe that mismatched tires (brand) is a bad idea, and a false economy. I also know for a fact that the carcass doesn't have to be showing for a tire to be at the end of it's useful life. Frank just fukkin rocked today, and the owner of the mint FJ1100 trying to keep up (also on Azzaros) could not believe that what he thought was a sport-cruiser was able to wax his ass so bad on his road. He wants me to find some magnesium feelers for the pegs, as long as he has to follow, he said, might as well give 'em a show..... :lol:

 

[FJReady]

Now thats what I'm talking about. Thank you very much Mark and Radman for putting some much appreciated light on this for me. I'll just do both and only worry about breaking in the one set.

Thanks again, have a good weekend.

FJReady

 

[yamaha1300rider]

Jeez

I get thru tires at a rate of knots so it would be no big deal changing one at a time

The most expensive part of keeping the fjr for me

I've spent GBP 600 on ties in the last year but get only 7k from front and 5k from rear :exclamation: You guys from us must have different road surfaces or ride at different speeds or mainly freeway (other than twisties), as I am not an aggressive rider

Paul

01 fjr

uk

 

[Bounce]

Some parts of the US use a compound in their roads that helps with grip but at the cost of quicker wear on the tires. Tires known to last much longer have been known to toast out on a 24 hour rally. It's a combination of the road surface, the 100+° (F) ambient temps and the 1000+ mile day that work together to eat through brand new tires in short order.

In regular riding on OEM stones, I saw 6k miles on the rear but the front was so badly cupped I swapped tires as a set. And I'm not considered an "agressive" rider by anyone but the Wingsters with whom I used to ride.

Point of reference: I average about 9k to 10k miles on a rear Pilot Road and about the same on Avons. However some western US roads would drop that down by 1/3rd.

 

[mech 1 twa]

I replaced rear Metz at 4500 with Avon. Bike steers well, no handling problems. Now at 6700, new front Avon going on this week. Profile of front Avon is different than Metz. Should improve turn in.

I was happy with tire miss-match. Should be OK for you.

 

[wontica]

I have a partially worn Stone on the front a new Avon on the rear, and the bike corners as smooth as ever. I've kept the front at 42 psi and the cupping is minimal.

 

[escapefjrtist]

Just replaced my well worn OE Metz4' s with Pilot roads. After taking them out for their first ride, have to agree with radman's excellent writeup and others comments. The worn tires were not "planted" in corners, darty, and wouldn't hold a constant line. You really don't realize how bad the tires are until starting out fresh.

I've only got about 100 miles on the PR's, but so far the handling difference is amazing. Although I could have gotten another 1000 miles on the old front, replacing the pair is the way to go.

BTW, another reason for the change is CFO is 2000 miles round trip. Have to at least keep radman's taillights in sight h34r: Also.....the local newly opened chopper shop did a mount and balance for $10 each. Had a brand new Coats machine and IIRC Snap-On spin balancer. Not a mark on the rims, and very smooth so far......

--G

 

[throttlejockeyTJ]

The Different types of tires were sumerized on another board. It is probably best not to mix V, U, & O tires front and back. Or radial and bias ply. When asked about mixing tires Kenny Roberts said, "If it works for you. DO it!"

TIRE PROFILES

Once I get the bike down to a certain point it just doesn't want to turn any tighter.

No confidence at lean, basically.

Ok, it's "Profile Discussion" Time!

Three basic profiles: V-Shaped, O-Shaped, and Elongated U-Shaped.

V-Shaped Profile: VERY sharp center and the sides fall away very quickly. Designed to make a bike change directions FAST. Not so stable vertically and often described as a bit twitchy. Also described as "Falling into turns". Very light pressure on the bars drops the bike into turns F-A-S-T. The older Michelin Pilot Sports were a V-Profile tire.

O-Shaped Profile: Basically, a very smooth constant arcing tire profile. Designed to offer constant pressure at the bars at increasing lean angles. More stable vertically than the V-Profile, but faster turnin than the U-Profile. To imagine an O-profile, cut the "O" directly in half across the O - that's the constant angle I am talking about. To get the bike to lean the first 10 degrees requires no more effort than making the bike lean another 10 degrees and then another 10 degrees. Metzler Z6 is an O-profile.

U-Shaped Profile: Ok, more of a fat, wide U. Very broad center (on a 6" wide tire, the center 4" will be near flat or slightly sloped) with slight, gentle sloping for the first 15 degrees, then increasingly steeper sidewalls. Extremely stable in the straights, easy turn-in for the first 10-15% of turn. However, turning beyond that first 15% gets inreasingly harder, requiring increasing pressure on the bars. It simply takes a lot more effor to "get the tire to the edge". This is intentional in the design of the tire. Flickability is sacrificed for Superb high speed stability. Michelin Pilot Road is a U-Profile. At the absolute extreme, the 300 series super-wide cruiser tires examplify the U profile to an almost completly flat extreme.

I hope that makes sense. In comparison between the Metz Z6 and the PR, the Z6 feels like "riding a knife's edge" - it almost feels unstable in the vertical position and wants to change directions very quickly. The PR on the other hand feels planted at any speed, even 5 mph. Superb stability is the name. I too have 1/3" "chicken strips" on my PR's (whereas I had no chicken strips at all on my Z6's) despite my best efforts. The PR just doesn't want to lean further by design. Simply put, I am not able to push the PR's profile deep enough into a turn to get to the edge the ay I was on the Z6's.

You have a "U" - profile tire. It's stable, handles well for it's shape, has very good grip wet & dry, and will wear like pig iron.

That's what you bought.

That's how they were designed.

I hope that helps.