I'm in need of some new tires. I'm going with Avon AM26 Roadriders (thanks in part to gjJack's tire log) due to their good performance and looong tire life. I've been running the cheapest Shinko's since I've owned my bike and I don't like how they perform in corners - lots of slipping, etc. It's kind of sketchy. Time for an upgrade.

I'm not ordering the tires for a few days, but I have them added to my cart on Motorcycle Superstore.

My sizes are 110/80-17 front and 140/70-17 rear.

How will this affect the handling? How does increasing the diameter of the front tire affect handling? The wiki says it will help the speedo's accuracy, but that's it. Also, will the wider rear tire help with cornering stability?

I have Avon Roadriders...really like them...seem better than the OEM Bridgestones...and lot longer life...   no noticeable deficiencies in handling...

But  why not just buy the stock sizes?

Cookie

Quote from: justafifteen on July 20, 2013, 05:11:15 PM
I'm in need of some new tires. I'm going with Avon AM26 Roadriders (thanks in part to gjJack's tire log) due to their good performance and looong tire life. I've been running the cheapest Shinko's since I've owned my bike and I don't like how they perform in corners - lots of slipping, etc. It's kind of sketchy. Time for an upgrade.

I'm not ordering the tires for a few days, but I have them added to my cart on Motorcycle Superstore.

My sizes are 110/80-17 front and 140/70-17 rear.

How will this affect the handling? How does increasing the diameter of the front tire affect handling? The wiki says it will help the speedo's accuracy, but that's it. Also, will the wider rear tire help with cornering stability?

Quote from: twocool on July 20, 2013, 06:23:25 PM
But  why not just buy the stock sizes?

I haven't bought them yet, which is why I'm asking what difference they make. I know the larger front tire will help the speedo, but if it has bad effects on the handling I'll change the size before I buy. Same with the rear tire - right now I haven't 140/70 selected because it seems a slightly wider tire will help with handling and look a bit better.

Dude.....the engineers and designers at Suzuki know what they are doing.......

Arbitrarily changing things on your bike, especially tires, will not likely "improve" anything........and most likely ruin the bike's handling / performance.......at best there will be no noticeable difference...

In America, there is a false impression about everything... that "bigger is always better"

If you think that fat tires "look cool"  well go for it.......If you think that will make the bike perform better...OK go for it.....but that is all in your head.........


We've had long discussions about the inaccuracy of the speedo on "all" motorcycles........This is done purposely by the manufacturer.........If you want accurate speed...go buy a $75 gps.......If you change the tire just to get accurate speedo (which is a dumb reason in the first place)...you will find the the odometer will be way off..........you can't hae it both ways


It's a free country...do what ever you want....but face reality.....don't kid yourself.......don't try to make the GS500 something it is not and will never be.....

In the grand scheme of things...big tires or not ...doesn't matter a hoot..Make your choices and be happy!

Cookie

Quote from: justafifteen on July 20, 2013, 09:22:12 PM

Quote from: twocool on July 20, 2013, 06:23:25 PM
But  why not just buy the stock sizes?

I haven't bought them yet, which is why I'm asking what difference they make. I know the larger front tire will help the speedo, but if it has bad effects on the handling I'll change the size before I buy. Same with the rear tire - right now I haven't 140/70 selected because it seems a slightly wider tire will help with handling and look a bit better.

I have a 140 rear .... As does Mister ....

I don't know that I can use the wider section effectively with my current level of riding skill .... Not that I'm a wobbly grandma rider at all .... But overall the bike will do more than I am usually willing to push for! ...

I didn't notice any detriment to handling though..... And ANY NEW rubber will always feel BETTER than ANY OLD rubber .... Theoretically you could have a clapped out 'top of the price range tyre' ... Fit a new 'super budget tyre' ... And the cheapo will feel better and 'handle more' than the old one ... 

Apart from a few important things like not mixing radial and crossply a certain way ...(And I can't remember which way it is right now.... Though its likely quite a few that do remember will chime in) .. Keeping to within acceptable size changes to avoid fouling any bodywork or structure ... And making sure you maintain pressures correctly plus inspecting regularly for any damage .... Then your particular tyre choice shouldn't matter so much!

The front size change? .... Meh I dunno .... It's pretty hard to affect speedo by profile/section size that much AFAIK ... Most of these bikes are 10% out and gaining that much difference would need a more drastic difference than that to 'correct it' ... Plus a 10% difference is real easy to do quick in your head if you suddenly notice a police radar or something .... A 5% difference wouldn't be too bad either.... But what if you end up with a 6% or 3% or something?? ... Hard to flip those numbers in your skull while also concentrating on riding and how far away that po-po is!?

Good advice by twocool though ... Do whatever floats your boat ... But don't expect a GP or WSBK bike out of it! 

Quote from: twocool on July 21, 2013, 03:59:41 AM
Dude.....the engineers and designers at Suzuki know what they are doing..................

But they did this thing, choosing the GS500 tire sizes, back in the 80's and perhaps would do a different thing now almost 3 decades later?  Can hardly find a 130 rear tire on todays small bikes:



Even Suzuki's new to the US GW250 has a 140 rear and Honda's new 500 has a 160.  By the way it is almost identical in overall dimensions and in weight to the old GS500.  Based on the GW250's weight we have been speculating on it's coming out with a new 500cc engine soon, any bets on the rear tire size it might have?

I've run 110/70, 110/80, 120/70 front and 130/70, 130/80, 130/90, 140/70, 140/80, 150/60, 150/70 rear tires on my GSs on the stock 3.0 and 3.5" wheels.  All of the tires I've run have been tire/rim fitments approved by the tires maker except the 150/60 rear.  I've always felt that the type of tire, ie bias, radial, supersport, sport touring, touring, etc has more effect on handling than the size does within the relatively narrow range of sizes I've used.  A different tire compound means more than a small difference in width.

Can't possibly comment on all the tires I've run on my GSs over the past 14 years and 175k miles but I'll mention the ones the OP has questioned.

Have noticed little difference in the 110/70 and 110/80 fronts as far as handling but do prefer both of the 110s to the 120 I have on now.  The speedo error is cut in half with the 110/80.

Can't hardly tell a 130 from a 140 side by side but the 140 do last longer and the 150 even longer yet, so why not go with the 140 at least?

I think the best overall handling tires I've had on my GSs is still a 110/80 bias Lasertec front with a 150/70 radial Roadattack rear I ran a few years ago but the Roadriders I've used the last 40-50k miles come close enough for my current needs and are much more economical.

http://www.gs500.net/gallery/data/500/GS500tirelogs1.jpg

"Dude.....the engineers and designers at Suzuki know what they are doing" 

Not entirely accurate
They knew at that time, for size, weight, power, AND...........COST EFFECTIVE SUPPLY to put the bike on the showroom floor.

I liked the michelin pilot's, now its pilot 2's and something else.  I remeber they held very well even when agressive, very forgiving and let you know well in advance when the limit was coming.   the sizes i use to get was 120/70/17 front and 140/70/17 rear.  i havent had to buy tires for some time so im not sure what else is available.   my old 82 gs750E used bridgestone spitfires, they were a dual compound tire, grippy on edges and harder on centerline, they held up well till i got into dragging the pegs around corners then heat cycles started to show.

I don't seem to have any trouble finding 130's.....Avon's now available for about $100

But tell me what exactly is gained with a 140 over 130???

Yes, you did mention "wear"...but really...how many more miles??

I could see a heavier tire as being a detriment....rolling weight hurts performance more than non rolling weight........But could anybody actually see any meaningful difference?

Jack...you've tried all those tires, over all those miles...any one really stand out?  Or are the differences so insignificant as to not matter at all?

Fat tires are mostly a "style" thing.......at least on a GS500......IMHO..

Cookie

Quote from: gsJack on July 21, 2013, 07:36:20 AM

Quote from: twocool on July 21, 2013, 03:59:41 AM
Dude.....the engineers and designers at Suzuki know what they are doing..................

But they did this thing, choosing the GS500 tire sizes, back in the 80's and perhaps would do a different thing now almost 3 decades later?  Can hardly find a 130 rear tire on todays small bikes:



Even Suzuki's new to the US GW250 has a 140 rear and Honda's new 500 has a 160.  By the way it is almost identical in overall dimensions and in weight to the old GS500.  Based on the GW250's weight we have been speculating on it's coming out with a new 500cc engine soon, any bets on the rear tire size it might have?

I've run 110/70, 110/80, 120/70 front and 130/70, 130/80, 130/90, 140/70, 140/80, 150/60, 150/70 rear tires on my GSs on the stock 3.0 and 3.5" wheels.  All of the tires I've run have been tire/rim fitments approved by the tires maker except the 150/60 rear.  I've always felt that the type of tire, ie bias, radial, supersport, sport touring, touring, etc has more effect on handling than the size does within the relatively narrow range of sizes I've used.  A different tire compound means more than a small difference in width.

Can't possibly comment on all the tires I've run on my GSs over the past 14 years and 175k miles but I'll mention the ones the OP has questioned.

Have noticed little difference in the 110/70 and 110/80 fronts as far as handling but do prefer both of the 110s to the 120 I have on now.  The speedo error is cut in half with the 110/80.

Can't hardly tell a 130 from a 140 side by side but the 140 do last longer and the 150 even longer yet, so why not go with the 140 at least?

I think the best overall handling tires I've had on my GSs is still a 110/80 bias Lasertec front with a 150/70 radial Roadattack rear I ran a few years ago but the Roadriders I've used the last 40-50k miles come close enough for my current needs and are much more economical.

http://www.gs500.net/gallery/data/500/GS500tirelogs1.jpg

i should mention... i said to the bike tyre man... "put a set of Pirelli Sport Demons on that for me please mate!" .. he did.... was actually about 3 months before i twigged to the 140 size change ... didnt worry me that much .. 

So this goes to my theory of "insignificant" or "not noticeable"

OTOH....I hear that Pirelli has a soft and sticky compound...so you may have noticed that....but it is not the tire size that makes a difference as compared to the compound and other design features...


Cookie

Quote from: Janx101 on July 21, 2013, 06:11:58 PM
i should mention... i said to the bike tyre man... "put a set of Pirelli Sport Demons on that for me please mate!" .. he did.... was actually about 3 months before i twigged to the 140 size change ... didnt worry me that much .. 

yeah pretty much ... i was impressed with 'new' rubber anyway ... the OEM battleax's were pretty fubar .. not down to canvas level .. but the rear was squared off from PO .. and the front had raised edges on the tread pattern ..

i did notice that the bike seemed to 'tip in' more and smoother when cornering up the local mountain rd .. but at the time i just put it down to fresh non squared rubber.. 

unfortunately for quite a while my riding time chances have been sporadic enough that my recall of any 'changes' is sketchy at best .. and i vary between 4/10 dedication (for my personal rating) .. on the freeway and up to 8/10 on twisties 'if i feel like it on a good day' .. even my 10/10 if i cared to push that hard ... would not exceed the bikes abilities i think .. but everyones skill level and perspective is different!

saying that though ... i DO notice the bike feels weird if the pressure is down on front or rear ... only recently got the little air pump at home working again (in one of those battery booster/jumper with air pump combo's) .. had a split line on the little hose... so i used to just ease down the road a km to the local servo and check the pressures there ...

forgot/didnt bother one day and was cruising up the freeway .. it even felt odd changing lanes.... when i did pull up and check it the front was down to 18psi warm/hot tyre ...  .... my stupid!! .. the rear wasnt that bad at 25psi .. normally i put them at 34-36psi ..

so yeah .. i notice the handling changes more from low/high pressure than the actual rubber or sizing... thats my perspective from riding experience so far! ...

also.... while its good to be excited about being out on the bike ... and i always check my fuel/oil/air now ... im just so glad to be out for a ride that often i just concentrate on the riding .. without worrying too much about 'feel of this/that' or 'perfect/crap' line through there... 

the front spring change to .95 sonics .. now that was noticeable! .. 

Quote from: twocool on July 21, 2013, 06:05:48 PM
Jack...you've tried all those tires, over all those miles...any one really stand out?  Or are the differences so insignificant as to not matter at all?

Tires have changed a lot in the 14 years I've ridden the GSs and so have I.     I used mostly Dunlop touring tires on the four 400-750cc Hondas I put 230k miles on before the GSs and got 25-30k miles from the rears.  I tried touring tires on the 97 GS early on and found the GS wanted to go around corners much faster than the K491 rears did but they did teach me how to catch a breaking loose rear end.   

Then I tried a 2nd BT45 rear and it was half worn out in 2k miles, got about 9.5k miles from a previous BT45 rear but had picked up the pace quite a bit.  Kept a pic to show it was worn all over and still in good shape when half worn out:



Next I tried radials a 110/70 Z4/130/80 Z2 combo and they were a great improvement, we quit slowing down in the corners in the rain after that and the rear Z2 went 14k miles and I was a radials for GSs fan after that.  Have used a number of radials on the GSs since then.

Then the new generation bias ply tires came out with the multi arc profiles and modern compounds like the radials had and the once great difference between radials and sport touring bias tires including tire life was now close.  Now I don't think there is that much difference between the new generation Demons, Lasertecs, Activs, Dunlop GT501, or Roadriders and the current sport touring radials not including the supersport tires that are really overkill on the GSs.

I've done most of my last 40-50k miles on the Roadriders so I guess they are my tire of choice now.  But you can't go wrong with any of the new bias tires including the BT45 that was upgraded in profiles and compounds after the others came out.

The Lasertecs 1st and Roadriders 2nd are my favorite front tires being the best I've used on construction grooves, heavy lines, open grate bridges, etc. for stability. I never liked any of the radial fronts they beveled badly like this Z4 pic and are worn out on the bevels first leaving a lot of center tread unless you ride a lot of srraight roads.   



As I mentioned above the 110/80 bias Lasertec front with a 150/70 radial RoadAttack rear were my favorites as far as all around spirited riding goes but the Roadriders more than meet my needs now and are much more economical.

I run a 120/70/17 front and 150/60/17 on the rear on a 4.5 gsxr wheel and it is far far better than the 130 Bridgestone that was on there. I have a conti road attack now which is a soft compound tyre compared to the dual compound Bridgestone but I have worn all the way to the edge of the 150 and I have far more grip on the edge of the tyre as there is always more rubber on the Tarmac at any angle.

Suzuki did know what they were doing but not solely for handling as it was built as a cheap commuter and not a sports bike so the handling can be improved, mine handles so much better than stock and I think a major factor is the tyres.

I don't know much about putting wider tyres on stock rims but take into account the profile aswell. The profile is a percentage of the width so a 140/70 is taller than a 130/70 which will make the bike drop into corners a tad quicker.

"Don't make a GS something its not" my GS handles as well if not better than my RG250 and gsxr750 it will easily keep with the big bikes on twisty roads which is impressive for a 45bhp bike so don't listen to people saying negative things like that. Make your GS into what you want to, I did and I love it!!

more important than speedo reads, is matching the front to rear profiles. sticky or long wearing, if its a proper matched set, it will make you happier.



I stuffed a 180 on the gs 3.5" wheel last week, just to see if it would seat the bead and hold air. completely unusable, completely dumb, but had to try it. its a gross exaggeration of why too wide a tire on a thin wheel is not good.


get the rear profile too shallow, and you'll run the edge into oblivion. the opposite and turn in will suck.

id stick with stock profiles on a gs, it always performed well, for me.

As I mentioned above a 110/80 bias Metzler Lasertec front with a 150/70 radial Conti RoadAttack rear were my favorite set for all around spirited riding.  Mmmm, made by different tire companies, different profiles (80/70), different construction (bias/radial), and both bigger than GS500 oem tires (taller/wider).  But they both were made in Germany, doesn't that make them a proper matched set?

Why not a 180 on a 3.5" rim?  A 200/70-15  ME880 is a Metzeler approved oversize fitment on the 3.5" rear rim of a VT1100.  Guess aspect ratio does matter, a 180/55 could be a bit tight.

I have a small bit of experience with tire compounds; enough to say that for cars the difference can be quite significant from year to year, and not always for the better! I have a set of seriously worn out performance tires that are still better handling in the rain than my nearly new all terrain tires. Both are higher end tires that are made with new tech, allowing my 30 year old car to vastly outperform the tires that were available for it when new.

Reduced tire wear on the wider tires is most likely the result of more area to dissipate heat from. Racers using too wide a tire often can't heat it up enough to get the traction they need to perform at the edge. Not that this is something we run at as street riders!

A big change has occurred in the bicycle industry recently with more wheel makers going to wider wheels for racing bikes with the idea being less sidewall flex and a more usable edge of the tire. This makes a lot of sense to me as any sidewall flex while cornering has an influence on handling confidence.