Spitfire S11 for my XS2

[72XS2]

Hi, I have to order two new tires for my XS2 to continue my rebuild. I will order two Bridgestone/Firestone Spitfire S11. I have a question about the rear tire. The stock size is 110/90-18. I would like to go to a 120 or a 130 tire. I just want something a little bit wider than the stock size. Is there someone who try this on their bike ?

 

[5twins]

I had a 120 and didn't like it. It slowed down the steering and handling. I don't think a 130 would even fit and if it did, I'm sure it would be even worse in the areas I just mentioned. Your bike was designed to use a 4" or 110 rear tire and works best with that size.

 

[tonyc]

I agree with 5twins I also run a 110. I have a BSA a-65 and they are noted for good handling until you use wider tires.

 

[pamcopete]

Ditto on the above. I have a stock '81/H with the stock 130/90 16 rear tire. I also had a stock '78/E with stock sized tires. The '78 handled much better than the '81/H. I sometimes think that I should have kept the '78 because it handled so much better.

I also have a Honda CB450 and the PO actually managed to install a 4 inch rim and 5.00inch tire on the rear! The bike handled like a truck, or worse, so I soon got rid of that rear tire and installed a stock sized rim and tire in it's place. Now the bike handles great, better than the '81/H XS650.

Big rear tires are what happens when the marketing guys think they are engineers...

 

[xjwmx]

I think wider tires are supposed to "handle better" going in a straight line - more inclined to go straight - the opposite of what most people think of as good handling, probably. So I wouldn't say one handles "worse" than the other unless it has some instability problem. Depends on what you want.

 

[yamasarus]

I run S11s on almost all my vintage bikes. They handle great and last well. Just ordered another set for my current restoration project-TX650A. The correct size interchange is

400-18 120/90-18
325-19 100/90-19

I am sure turn in would be faster with a smaller tire, but why would you? If the handling is okay I want the larger tire patch and load rating. If the handling is not okay I find another tire. Use the correct sizes.

 

[cros36]

i have the s11 130 on mine. its fine, people worry too much. jesus, stock bikes these days come with 150's.

 

[XSLeo]

Wide tires sell bikes. Thats the only reason they are on a bike. As far as ride and handling a 130 is about as wide as you need. The 100 or 110 wide tires handle best on the classic bikes.
A bike that is designed and built to work with the wider tires like the newer crotch rockets can use a wider tire. Even they don't need a 150 + tire to handle well. Thats just what the costumer thinks looks good, nothing to do with function.
Leo

 

[72XS2]

Thanks guys. I still don't know what I'll order but thank you for your inputs. You'll find out in my build thread.

 

[72XS2]

Finally, I ordered a 120 tire for the rear. I don't know how it fits on other years but on my 1972, it hits the chain guard a little bit. Nothing that can't be fixed but If I had known, I would have bought a 110. I know, some of you told me to go with a 110 but ...

 

[yamasarus]

Check your chainguard mounts. That 120 should fit easily. I even use them on my old bikes that have a drive shaft and used 400-18s. If your rear shocks have been changed they may be pushing in on the chainguard. Just sayin' this should not be a problem. I could see a 130 rubbing but not a 120.

 

[72XS2]

Check your chainguard mounts. That 120 should fit easily. I even use them on my old bikes that have a drive shaft and used 400-18s. If your rear shocks have been changed they may be pushing in on the chainguard. Just sayin' this should not be a problem. I could see a 130 rubbing but not a 120.

Thanks! I replaced the rear shock, I will check it tomorrow.

 

[XSLeo]

Tires, even if all 110 or 120 can vary in the width. Tires from one manufacturer can very from model to model as much as from brand to brand.
If you have an angle grinder you can take a bit of the edge off the tire to get clearance.
I had a 140 wide 16 inch tir that hit on both side of the swing arm just a bit. It had a bit too much side to side wobble even with the tire properly mounted on the wheel.
I put it up on the center stand, idling in gear, I used my angle grinder to remove a bit of the point where the tread meets the sidewall until it quit hitting.
Not an ideal way to do it but it worked until the front tire wore out and then I put on the right size tires.
Leo

 

[CDNTX650]

i have the s11 130 on mine. its fine, people worry too much. jesus, stock bikes these days come with 150's.

like the 190 on my ducati....little more tq to contend with though