Whats the biggest/widest tire that can be used in the front (89up) with or without fender/brace mods?
What comes to mind is "Why?"
I asked this before.......simply because I have the OEM front tire from my supermoto when I swapped that to full race slicks. I was gonna spoon the 120/70 Pirelli on the GS to get through MD state inspection but I was advised against it from folks on here and elsewhere. Unlike a sportbike, the GS has a tiny rear tire (130), so to make a tire size change on the front would drastically change the handling. sportbikes are a bit less finicky where you have a meaty 190 on the rear and want to change to a different sized front tire. If you put a bigger front tire on the GS, it will ride like you have the same tires front and rear....My 2 cents. That being said, I just took delivery of a new BT 45 to spoon on mine.. :woohoo:
You can fit 110/70, 110/80, and 120/70 fronts and 130/70, 130/80, 130/90, 140/70, 140/80, and 150/70 rears on the GS500/E/F bikes on the oem 3.0" front and 3.5" rear rims. I've run all those sizes on my 97 and 02 GSs.
The 110/80 and 120/70 fronts come close to the fender and I doubt you could get anything larger on without fender mods or removal. All those rears have ample clearance all around except the 150/70 will touch or almost touch the brake torque brace requiring a bit of a bend in the brace, a quick and easy mod with a BFH.
Last front I bought was a 120/70 Roadrider and I bought it just because it was the only one of those sizes that I hadn't tried just in case you gotta ask. :icon_lol: I had a 150/70 rear Roadrider on it when I mounted it and later changed the rear to a 140/70. I really liked that 120/70 front on my 3.0 wheel at first as it was very responsive being pinched down a bit on the narower wheel and had a nicely rounded shape. Later when it was half worn and the shape flattened a bit I wasn't quite as happy with it and having a half worn 110/70 mounted on a wheel available I put it on and liked it better. Probably felt better as much due to the smaller dia making the rake a bit steeper as it did due to the shape. If I needed a quick change on the front though I wouldn't hesitate to put that 120 back on.
Keep in mind that a 120/70 that measured 120 mm wide on it's proper 3.5" wheel is pinched down to only about 115 mm wide on a 3.0" wheel:
(http://img.photobucket.com/albums/v443/jcp8832/CalcTireDims.jpg)
Thank you all, We live in the country and freshly graded gravel roads are common. It's a compromise for sure. Sometimes a wide tire will float on gravel and make you crap your pants, sometimes the "knifing" of a narrow tire will make you crap your pants. :embarassed:
Quote from: highsideshurt on February 03, 2012, 01:20:01 PM
Thank you all, We live in the country and freshly graded gravel roads are common. It's a compromise for sure. Sometimes a wide tire will float on gravel and make you crap your pants, sometimes the "knifing" of a narrow tire will make you crap your pants. :embarassed:
True story..
but not to thread jack, I need new tires, what brand/size should I be looking at? mine are a "Tad" bit weather rotted and bald.. :D Safty? NAH!!!
Jack is the real tire expert having run almost everything under the sun. Search for some of his tire posts. The stock Bridgestone BT45's are a decent tire. Pirelli Demons are a step up. And if price is a big concern you can go with Kenda K671 Cruiser ST. I run those on my beater '89 and don't notice a huge handling difference between them and the BT45's on my '01. I haven't put enough miles on them to know how well they wear. My favorite tires are Michelin Pilot Powers but they are not available in stock GS sizes.
-Jessie
Edit: Hey Jack, ever run a 150/60 rear on the sock 3.5" wheel?
I've never run a 150/60 rear tire for two reasons. (1) They are generally supersport radial tires with very sticky rubber and a shorter life than the sport touring tires and I like the compromise of sport touring tires that have good performance balanced with good life. (2) The 150/60 tires are not approved for fitment on 3.5" rims in this country by any of the tire makers and never have been as far as I know. All of the tires I've run have been approved by their makers for fitment on our size rims.
However, the 150/60 supersport radials have been quite popular with both GS500 and EX500 (Ninja 500) owners; Pilot Powers in particular for performance use. You can see from this list of users from the EX-500 forum that have bothered to list theirs how popular they are. The Ninja 500 has same size oem tires and rims as our GSs have since 1994.
https://spreadsheets.google.com/pub?key=p9OvigvZMFSbc6PJadCGCNQ
J_Walker, tire choice depends on how much you want to spend and to what use you intend to put them. A performance tire for track days and/or for fun in the mountain twisties or a longer life tire for good commuter service but you still want good performance in them too. I find the Avon Roadriders meet my current performance needs and give very good life doing it and am on my third set of them now. Here's a good read of a bias ply test done on a GS500 on a track in England you might want to start with, they liked the Roadriders too. :thumb: The stock 110/70/17 and 130/70/17 sizes should work just fine until you find a good reason to try other sizes.
http://www.ex-500.com/wiki/index.php/Tire_Comparison
Quote from: gsJack on February 03, 2012, 06:05:41 PM
However, the 150/60 supersport radials have been quite popular with both GS500 and EX500 (Ninja 500) owners; Pilot Powers in particular for performance use. You can see from this list of users from the EX-500 forum that have bothered to list theirs how popular they are. The Ninja 500 has same size oem tires and rims as our GSs have since 1994.
https://spreadsheets.google.com/pub?key=p9OvigvZMFSbc6PJadCGCNQ
Thanks Jack :D That is exactly the information I wanted. I'm thinking of turning one of my parts bikes into a track bike. The Pilot Powers are what I run on my sport bikes and I like them. I thought they'd be a good choice for the track bike if they would fit the GS stock wheels.
-Jessie
Quote from: gsJack on February 03, 2012, 06:05:41 PM
I've never run a 150/60 rear tire for two reasons. (1) They are generally supersport radial tires with very sticky rubber and a shorter life than the sport touring tires and I like the compromise of sport touring tires that have good performance balanced with good life. (2) The 150/60 tires are not approved for fitment on 3.5" rims in this country by any of the tire makers and never have been as far as I know. All of the tires I've run have been approved by their makers for fitment on our size rims.
However, the 150/60 supersport radials have been quite popular with both GS500 and EX500 (Ninja 500) owners; Pilot Powers in particular for performance use. You can see from this list of users from the EX-500 forum that have bothered to list theirs how popular they are. The Ninja 500 has same size oem tires and rims as our GSs have since 1994.
https://spreadsheets.google.com/pub?key=p9OvigvZMFSbc6PJadCGCNQ
J_Walker, tire choice depends on how much you want to spend and to what use you intend to put them. A performance tire for track days and/or for fun in the mountain twisties or a longer life tire for good commuter service but you still want good performance in them too. I find the Avon Roadriders meet my current performance needs and give very good life doing it and am on my third set of them now. Here's a good read of a bias ply test done on a GS500 on a track in England you might want to start with, they liked the Roadriders too. :thumb: The stock 110/70/17 and 130/70/17 sizes should work just fine until you find a good reason to try other sizes.
http://www.ex-500.com/wiki/index.php/Tire_Comparison
so by that last link you had there, it seems like the stock are best, and I should just buy them again?
Jessie, copied from the Racers Corner linked on the original front page of gstwins.com:
On a racing GS, the front tire size is the same as stock (110-70-17). For the rear, most racers I know use a 150-60-17 (stock is 130-70-17). The fitment guide will tell you the rim is too narrow for this tire. It is, but this does not result in bead failure, even under extreme racing conditions. It does modify the profile enough so that it impossible to get all the way to the edge of the tire. If you can't live with that, you can have your wheel widened to 4 inches by Kosman Specialties (http://www.kosman.net) for about $375, but then you won't be legal in Supersport class...................
That info while still good is a bit dated now, since then many GS racers have been running the BT-090 tires and more recently the BT-003 racing street tires both of which are available in the 140/70 as well as the 150/60 size for 3.5" rims.