lean angles

zxBrendon · 04-09-2008, 10:01 AM

when i was watching gp the other night and noticed the riders getting 55-60 degree lean angles i was wondering if its possible to do on the tyres we buy, either race tyres or street tyres?

obviously you need the skill and confidence, but if it is possible do any of the racers at barbs get close to them lean angles?

also i noticed when they put there knee down they take the lean a bit further, i always thought the knee was a guide to the edge of the tyre?

lee · 04-09-2008, 10:29 AM

i know the 2ct pilot powers were bragging when they came out about the maximum lean angle they'd support. i think it was like 52 degrees. that being said, i think that assumes correct suspension setup, and the right amount of weight, and perfect conditions so it's hardly recommended to sort out some sensors and try push it.

i think 50 degrees would be relatively easy to pip with good quality slicks, i'd be rather hesitant on road tyres though.

thro · 04-09-2008, 12:04 PM

What lee said basically.

Also keep in mind they're racing on tyres designed for the stresses of high speed cornering for *realtively short periods of time*.

They only have to last one race. They're one-offs for that particular track/bike/environmental condition...

Your tyres have to last 5000-10000km or so in general for road use. Your tyres also have to be reasonably grippy from cold. You suspension also has to be relatively soft to deal with potholes, etc - race suspension doesn't.

Short anwer is I don't think you'll ever get those lean angles without a motogp style bike/setup/tyre - otherwise motogp bikes/tyres would be much the same as road bikes...

g0zer · 04-09-2008, 12:32 PM

perfect setup and perfect rider and same tyres, remember the GP bike probably only weighs 145kg.

the mass of your bike will influence lean angle too, the centrifugal force that is consuming your traction during cornering is a function of the mass.

likefry · 04-09-2008, 01:35 PM

As well as all the money that goes into the bikes the tyre companies would spend millions getting the absolute best tyre possible for the conditions.

Probably not very similiar to anything you can buy even with race slicks

xanthian · 04-09-2008, 01:42 PM

Sure, you can get those lean angles -- as long as you don't expect to be emerging from them upright. :p

Shit, I've got scuff marks on the top of my shoe from the other day when it got trapped between the road and gear lever, and I'd be surprised if I was doing 35. I'm 99% sure most bikes couldn't push a 60 degree angle even if their tyres could.

ApatheticEnd · 04-09-2008, 01:46 PM

The "lean indicator" thing they use in their broadcast isn't fed from the bikes telemetry system. It's a smalll gyro unit mounted in one of the camera bodies. They are crap and widely accepted to misleadingly high in their measurements.

They are reaching insane lean, no doubt, probably more like 52 degrees. You can fit a calibrated 2D datalogger to any bike for not insane money. Depends how many channels you want.

T_B R1 · 04-09-2008, 02:02 PM

Quote:

Originally Posted by xanthian

Sure, you can get those lean angles -- as long as you don't expect to be emerging from them upright. :p

Shit, I've got scuff marks on the top of my shoe from the other day when it got trapped between the road and gear lever, and I'd be surprised if I was doing 35. I'm 99% sure most bikes couldn't push a 60 degree angle even if their tyres could.

Thats why you ride with the balls of your feet on the pegs, don't let you toes hand under the lever unless want a broken foot. At very least ride on the arches of you feet but remember to shit your foot back from under the lever.

xanthian · 04-09-2008, 02:06 PM

Yeah, that was the wakeup call that I needed to start doing that for *all* turns. I didn't think I was leaning that hard, but I'm still proud of my battlescar (battlescuff?) nevertheless.

Murley · 04-09-2008, 02:14 PM

Xanthian: I was wondering what was going on, I thought you were shifting mid corner! I always ride with the balls of my feet on the pegs, not just turns - it just feels better

For tight corners I tuck the bottom of my foot up against the frame (outside edge of foot on peg) so my toes don't scrape the road

First time I felt my toe scraping on the road around a corner (while still on the peg) was a shock but it also let me know that I had entered the knee down zone

xanthian · 04-09-2008, 02:18 PM

Unlike a one-gear-fits-all 'busa, I've got 5 gear changes between 0 and 80. It's kinda hard to ride my cibbie having to move my foot back and forward every gear change, but I'm getting used to it.

DaveR6 · 04-09-2008, 02:26 PM

i wonder what stoners lean angle shows half the time

rabbit · 04-09-2008, 02:29 PM

I would bet your street tires would handle the lean angle your bike ground clearance will allow. whether that is 20deg for a Harley and gullwing prob about 35deg to 40deg for my busa and around 45+ for sports bike but no was are you going to get 55 - 60 lean out of a streetbike or street tires

I was watching the way Rossi and Stoner used there knees it looked almost as if they where using the drag from the kneepad to turn in harder on the tighter corners? Is that passable?

thro · 04-09-2008, 06:07 PM

Quote:

Originally Posted by xanthian

Yeah, that was the wakeup call that I needed to start doing that for *all* turns. I didn't think I was leaning that hard, but I'm still proud of my battlescar (battlescuff?) nevertheless.

Get into the habit of keeping both sets of toes on the pegs, unless braking or changing gear.

that way, you can't "forget" or "mis-judge" the corner and suddenly have to lean over much further than you thought (and thus get your toes caught).

you need toes on pegs when you start hanging off the side of the bike anyway...

Quote:

i wonder what stoners lean angle shows half the time

90 degrees.

tteksep · 04-09-2008, 09:23 PM

Quote:

Originally Posted by thro

90 Degrees.

Ya got that right!