Triumphrat

Jhtjon · 05-16-2008

What do you think of mixing tires. I really want to install a set of Michelin Macadam M50/M50E's on my Bonnie, however the 130/80-17 has been discontinued. I could either use a 140/80-17, 130/90-17 or use a Pilot Active 130/80-17. I am just concerned about mixing diffrent tire patterns.

BlackThrux · 05-16-2008

I went up from a 130 to a 140 in the rear with no ill effects, I think the bike actually handles better, I would be more hesitant to mix patterns than sizes, I have no explanation for that it just doesn't seem like a great Idea to me.....

Baltobonneville · 05-16-2008

130/90 is close and won't make much difference. My mechanic installed one on mine and I didn't notice until I put the bike on the center stand--the tire is a bit taller.

CAPTDON · 05-16-2008

140 works great!! Better than the 130!! Mixing? Ok but there is a thing about mixing radial & bias F&R. Dont remember which combo is the no no? I am HOPING to get the ft BS to last out the new rear - then I am gonna get a pair of Pirellis! Love the reports I have heard on them! Used to love them on my MG's & Jags!! The 140 is the way to go!! Someone here will tell ya the nono on the R&B mix. I cant remember?

surfdogx · 05-16-2008

I just had my 1st rear tire replaced (stock 130/80 Metzler ME2)(4550 miles) with a new Metzler Lazertek 140/80. There is some difference that I've detected. Definately fills the rear fender more. This is a good thing appearence wise. Handleing is slightly different now though. Hard to tell, but I have to concentrate to hold the turn smooth. Like before it flowed easily and almost automatically. Not that bad but maybe it just takes time to get used to. I only got about 150 miles on it so far.

Jhtjon · 05-16-2008

Actually the Pilot Active is a bias tire the Pilot active is replacing the Macadam

mecscc · 05-16-2008

Unless the tread patterns are radically different mixing them will likely not even be noticeable. In fact, if you really look at a lot of the OEM pairings the front and rear patterns aren't exact matches to start with. I would be reluctant to mix radials and bias tires, but know a lot of guys who intentionally run radials on the front and bias on the back. I have been running a Dunlop 404 on the front with a Pilot Activ on the rear for about 8K miles and the combo is better than the BT 45s, a matched pair, I had on before. Sue's bike runs different Bridgestone models on the front and the rear and the bike came that way from the factory.

No science here, just my own experience over the years.

vanson1200r · 05-17-2008

Being that the front tire is a bias ply and the rear a radial, make or tread pattern will have no effect on handling other than difference in tire construction from manufacturer to manufacturer. I dont know what I was thinking but I got 10,000 miles out of the rear stock tire and about 7,500 out of the front. I replace the front with another Metzler but next week I'll stick on an Avon maybe in the rear.

whatisit · 05-17-2008

it's not so much tread pattern that needs to match but the tire's profile, the "curve" if you will. If you've ever ridden with a really squared off back tire and a front that still retains it's rounded profile then got a new rear you likely noticed a great handling improvement on your ride home. Whatever change in handling comes from fitting a larger or smaller sized tire of the same model mostly comes from altering it's profile by fitting it on a larger or smaller rim. You squeeze it into a sharper curve or stretch it into a wider curve. This is not necessarily "bad" in itself, in fact it's sometimes done on purpose to increase the bike's willingness to turn in quickly or to add some stability to a twitchy bike. It's not advisable to go too far from spec, but a good tire shop should be able to advise you on what might work for you and how it may feel compared to what you had on before. They should also be able to tell you what model tires (within the same brand at least) have comparable profiles.