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Does tire width affect max lean angle?

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Lumberjack

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Jul 10, 2010
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Z1K, Street Triple R
So my Ninja 650r has a 160 back tire, and I see that the supersport bikes have a 180 or 190 tire on them - does the narrower tire mean the bike can't lean over as far before it runs out of traction?

I was imagining a bicycle tire, and was having trouble visualizing such a tire being able to support a bicycle at anything like the lean angle a sportbike gets.. And so I was thinking that this same principle would apply between a 160 and a 180 tire - is this correct?
 
The profile of the tire allows you to lean. Don't you even think about putting a wider rear tire on your Ninja 650r - it'll RUIN your handling.

I just switched the rear tire on my YZF600R from 185/55 (from previous owner) back to stock size 160/60. With the fatter 185/55 rear tire, the bike handled like a pig - felt real heavy, didn't want to turn. With the stock sized 160/60, the bike handles like a cat - feels like it's 100 lbs lighter, turns on a dime. :cool
 
Lumberjack said:
does the narrower tire mean the bike can't lean over as far before it runs out of traction?
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Sure doesn't. take a look at the 125cc road race series. Those guys have no problem dragging knee on their pizza cutter tires.

Also, don't forget to take the tire profile into consideration. The profile is the second number in the tire size, that has a lot to do with lean angle. Most 190 tires come in a 50 profile (the tire is 50 percent taller than it is wide). That's actually fairly flat. Your 160's can have a fairly agressive profile. The difference is, they don't have to apply 150+ horsepower to the track during corner exit. They can still support big lean angles, under the right rider. They don't need to be wider.
 
The width itself doesn't, but the width combined with the rim width does. It'll affect the profile of the tire, and THAT affects your max lean angle. But you won't get any more lean angle with a wider tire. Your 160 pretty much maxes it out. I'm on an SV with a 160 and I'll scrape my kickstand (and subsequently crash) before the tire runs out of lean angle.
 
Right on - I put Michelin 2CT PowerPure tires on there and they feel stickier than the stock for sure..

As far as their lean angle though - at the track, I'd lean it over a good bit, and it would feel like it was about to slide out, as though all the sudden the bike went waaay over onto the tire - I couldn't tell if this was just the PowerPure tire profile and I was on the side of the tire, or if I was indeed nearing a lowside.. Whenever that would happen, I'd immediately straighten the bike up a bit, feeling like I had to save it - thing is though, when I felt I went way over on the tire (more than the below pic - it's only happened a couple times, neither recorded), it didn't feel like it was slipping per se, just that all the sudden the bike "fell" into a much more dramatic lean..

When I checked the track pics I had some pretty good leans, but they didn't look as extreme at all as the motoGP pics and such (granted, they're pros and using race tires, but still, I'm trying to ascertain the limits of traction)..

Here's a pic of my bike at the track - those are the powerpure tire - does the bike look like it has much more lean angle in terms of the tires here? That's about as far as I've leaned it I think.. I'm not sure how we as riders are supposed to find the limits of lean angle without crashing at some point? I sure don't want to crash, but it would be fun to lean the bike over further (and thus go faster through the turns at the track) if I knew I had more traction available..

Situation is complicated a bit by the cheap suspension on the 650r though - the bike does not feel very planted at all if the corner is anything less the perfectly smooth/non-bumpy pavement..

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I wouldn't compare your leans to MotoGP racers. Those are just ridiculous angles that they reach with experimental tire technology and a team of engineers behind them. Your peg feeler isn't even on the ground in that picture (and I realize camber plays a roll). Those feelers are there for a reason. Your body positioning looks pretty good, which means you're far more likely to scrape foot pegs before your tires give out. You still have more room for error.

If you really want confidence, have your suspension set for your weight. It sucks in the 650r since nothing is adjustable, so you have to have your internals adjusted.

But if your main goal is faster lap times: lines. Once you've touched your knee down yay. The real trick to speed after that is learning the right lines. After that you have proper braking points and trail braking and how hard to get on the gas and where. But how far you can lean has little to do with how fast you're going to go. I've had people pass me on the outside when I'm dragging knee and it sure wasn't because they were leaned over further.
 
TheRiddler said:
I wouldn't compare your leans to MotoGP racers. Those are just ridiculous angles that they reach with experimental tire technology and a team of engineers behind them.
Click to expand...

I always thought there's danger in watching MotoGP and photos of those guys practically lying on the ground in the turns - monkey see monkey do would not work out too well for impressionable new riders (like me)... :(
 
Knee dragging at the track is like masturbating. Almost everyone does it, but it's mostly the inexperienced who are proud of it.
 
Yes it affects lean angle, but not quite the way you're thinking... :twofinger
 

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From your picture, lumber, you are in fact at your bikes maximum lean angle. If you want to go faster, you have to figure out how to balance the bike through a corner in a way that doesn't require leaning the bike as much. You've got to move your body off the bike and towards the center of the corner while making turns. This keeps the bike more upright for the same cornering speed. Your chicken stripes will come back. Once you figure this out, start increasing your speed and your lean angles will come back.
 
Anyone else get a little dissapointed when hanging out somewhere (such as The Wall) and some guy pulls up on an 80's GSX-R 750 with a 180 stuffed on the back.
 
If you really want a 180, you can pick up a ZX6 wheel and a kit from Zoran and make one fit right.

On the other hand, if you want to get faster you'd be better off getting your suspension set up right. A quality rear shock and at least springs/emulators in the forks would make a huge difference. A front end swap would be even better, at least once you get the right springs in the new forks.
 
Does a 160 effect max lean?

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No. That's with Woodcraft high rearsets, plus the relocator plate that's another 1.5 inches up and back, I think. So ~3.5 inches of lift on them and I'd still drag them at certain places on the track. Now, that happened because my BP sucks, but that's not the point...the point is the tires can absolutely take the lean angle.
 
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