Ok, heres the deal. This is my first year racing as several of you know. Being new to sportbike/racing, i have a question about tire size. Roebling Road last weekend i had my first victory in the Medium wt. solo 20. Was turning the best lap times ive ever had at Roebling (low to mid 1:20's the entire 16 laps). Bike is a bone stock right down to the suspension 99 R6. Bike was handling GREAT, according to speedo, going thru T9 @ 130-135mph and the Pirelli's were sticking like glue. Heres the question. This past weekend as i was cleaning up the bike, i noticed that when i had the tires put on at the track, they mistakenly put on a 160/60/17 on the rear rather than the 180/55. I know that having a 160 is gonna make the bike turn in quicker, but what could be the other possible consequences of running the smaller tire? Hell, as good as the bike felt, im HALF tempted to keep running that size. I bought 2 sets that weekend and didnt get into the 2nd set, theyre still in my garage awaiting mounting for the GNF and they ARE the correct size at 180/55. Just curious what the advantages/disadvantages would be at keeping the 160 size?? All thoughts and opinions would be greatly appreciated. Thanks in advance.
I thought having speedo was bad? 160 has less tire mass than the 180 Same concept as doing a 520 conversion. Lower un-sprung weight equals a motor that can crank power faster with less load. What im not sure about is the actual contact patch for a 160 versus a 180. If in full lean the angle of the tire to the ground should be close on both. but what about how much is actually grabbing? Of course im no expert but thought i would impart some type of answer
my only thought is what if 160 isn't enough tire to grab hold and stick on the bead, and it seperates at speed.
A 165 B/S slick is right for a 5.5" rim (and works fair on the SV's 4.5"), but for most DOT's the 180 is made for the 5.5. If you paid someone to put that tire on, I'd demand a free 180 to be put in it's place.
Tires are like breaks use what you feel good with. We use a 160 rain tire instead of a 180 rain on our r6's. The 160 needs differant rear shock eye to eye mesurement. the 180 has a differant profile to. In the dry I like the 180 over the 160 I think the tire has a better chance of staying in the proper heat range over a 160 more mass to get rid of the heat. As for the tire guys messing up mounting one tire out of hundres of tires a weekend they get a thumbs up for coming out every weekend to service us. It is ultimately our ass that we need to look out for it is our bike and we should know what we are riding. like does it have brakes gas in it coolant level oil level the proper air in the tires do we have our helmet and leathers on ect. It is not someone eles responcablity to make sure our hand are held go over your bike before you ride it. It is your life and maybe just be someone else that you effect as well. Not bashing anyone just that i have always felt it is my responceablity to check my bike out before i ride it. sure i have messed up and forgot to tighten a few clip-ons here and there but for the most part everything stays on the bike but i always blame myself for being a dumb ass for not checking it out myself. I think the heat is to blame for most of it..... we need inside tracks with ac
Thanks for the responses guys. Huff, i hear what your saying. I hadnt planned on "demanding" a new tire from Moose and the gang. Like i said, hell, i won the race on the 160 and had NO problems with it. I will mention it to them tho at the GNF just to let them know they really should look a little more closely at the tires they pick out. Im sure just like me and alot of people, when youre shootin the shit and working at the same time it'd be easy to pick up the wrong tire. I should have looked at it before mounting it up on the bike. I usually DO look at them just to make sure tire rotation is right but i neglected to do so this time. Now i have a 160 tho with just one solo 16 on it and one heat cycle that i'll have to sell.
Sell? Hell i would race that lucky tire again. Or at least mount that sucker on the wall next to your wood. Think of the stories you can tell.
160? Todd, I'm not expert, but usually the 160 is for a 4.5" wheel. If you liked the feel and felt that you had enough traction at lean angles, then instead of sticking with the 160 you might want to give the 170 a shot. Most manufacturers make a 170/60/17 that might be closer to standard size.. usually a smaller tire will make the bike turn in quicker, but sometimes will not have as much rubber on the ground at full lean. I'm kinda surprised that you didn't notice any odd feelings racing, but hey, first place is first place!!! I know that folks will play with tire sizes some but best not to stray too far from norm... it's kinda like moving from the 120/60 front to a 120/70- more traction at lean... Jeff
What front tire size are you running? The R6 came with a 120/60 but everyone puts a 120/70 on for racing. Was the bike loose at all in mid turns?
thanks Jeff......yea....i dont wanna risk fate. Im gonna go back to the 180. That was the main thing i was worried about was the contact patch at full lean. The tire never so much as broke traction the entire race. Like i said, i went into tuck thru T9 (hence the only reason i saw the speedo, it was right in front of my nose, i dont focus on it, i just glanced at it), saw 135 and thought to myself HOLY SHIT! thats the fastest ive EVER been thru there even tho i was told thats how fast i needed to go thru that turn to be competitive on the 600. But the tire just stuck, thats why i was completely surprised when i saw the tire size once i got home and was cleaning up the bike. Fastbtdrmike, i use the 120/70 on the front. made the 10mm adjustment in the forks to compensate for it. Bike handles like a charm.
First of all Todd, Congrats on the win. That is awesome. You have come a long way from the guy that almost high-sided in front of me and caused me to go muddin' on my GSXR that trackday I am certainly no expert on your tire question. But one thing, with the smaller tire your speedo was being very optimistic on your speed. I wouldn't put much faith in that. Just know that the bike felt good and you were going fast, that's really all that counts. See you at the GNF. Scott P. (I can identify with the "old guy" thing)
Hell I will take the tire from you. It will work just fine on the SV or the Hawk I just bought. And once again congrats on the win.
