Been trying to do more stuff on my bike as I've owned it, and been lookin to get a new front tire and realized the one the bike shop put on it last year is a 120/60 and my owners manual says it should be 120/70. It appears to ride fine, so I'm wondering if anyone can tell me if I should go back to the original 120/70 when ordering the new one? Oh and sure enough, I checked the back tire and it is different than the owner's manual says as well. Any tire gurus out there? Grasshopper
I would go back to stock size tires the 60 series is a shorter side wall and lowers the front end a bit, I ran 60 series on a few tracks where I wanted to quicken up the steering a bit but on the street you could damage rim if you hit a pot hole or something. so if you are replacing both tires go w/ manufactures listed sizes for your bike.
Thank you sir. That's the feeling I've been getting. Got the impression the guy I bought it from liked to race her quite a bit which gels with what you mentioned about the 120/60's.
on a 1280X 1024 resolution screen, the difference in 70mm to 60mm is precicely this much Thats the total heighth of your tire from rim to road that is missing. I have hit bigger rocks than that. The tire and manufacturers recomendations are built with safety and potential for destruction of parts when designed by engineers. There is nothing to worry about here. Manufacturers recommendation is 120/70 +/- 10 for both. I.e. 110/60 to 130/80 and any combination in there, is purely for riding comfort. again... I.e. a 120/70 stock size, is mounted with a 110/80, That would give you better handling in turns, and a much smoother ride. Taller side walls flex more than short ones, and thus absorb a bump in the road more like a cushion. IF!! and this is a HUGE "IF"... but IF you can tell the difference in your tire, being 10mm shorter, you would tell me that the seat feels slightly harder. So my comment to you is; Dont go into the shop and beat the owner with a wrench, because you probably cant tell a difference anyway, and because he probably got you a comperable tire for less money. And if you are still feeling raw about it, change the size up when its time for a new one. The tire you got is perfectly fine.
Thanks Ghost. Well, heck, now ya got me wonderin' if I should go with a 110/80. Oh the decisions, the decisions....
Yep, you are correct sir. So now I'm wonderin' if I should go back to the original 170/60 on that as well. It seems fine, but I have nothing to compare it with. So who knows.
I'm assuming you have the 8 spoke rear wheel. Most people are running the 180, it's a 5.5" rim. I have the same wheel on my '99 and use the 180. The 170 may give you quicker turn in but you'll probably find better selection with the 180.
Yeppers, 8 spokes. But if what you say about turning quicker with the 170 is true, I may have to give that a go. I have a Conti Road Attack on the back and have been happy with the wear on it so far (just went on a 2,500 mile road trip with my Dad), and they make a 170/60 so no worries trying to find the size.
A 70 is a much better race tire, in fact. The 60's were used for a while in the 1990's, but pretty much everything uses a 70 series now. My guess is that the PO put it on there because either 1) it was a tad cheaper or 2) that's all his dealership had in stock and he just wanted to get it done.
What caused the shift back and forth I wonder. Why were the 60's thought to be better in the 1990's and now it's gone back to the 70's. I'm finding myself more and more intrigued by this stuff. Ahhh, the mystery of the tire....
They really didn't go back and forth, more of a progression. In the late 80's there was a push towards low profile tires. As things developed the profile of and the fronts got 120mm wide they started with a 60 series profile. That only lasted a few years before Manufacturers realized that a 70 series provided better front grip, so they switched. Normally it took a model redesign before the changes were implemented. Some bikes continued to use the 60 for a while, I think it depended on the chassis seup. Most high-end performance bikes went to a 70 and all have stuck with it.
well now I can't wait to put a 70 on there and see if I can tell a difference. I admit I don't have any racing experience so I'm sure it'll be lost on me, but anything that can make my bike handle better, I'm all for. Thank you for your insight.
