Curves

[GoIllini]

I have a few questions about curves:

1.) The MSF teaches "Outside-inside-outside" curves, but folks on here talk about "following the line." Is this different? Does it mean that if I enter the curve 2 ft from the median line, I stay 2 ft from the median line through the curve?

2.) I'm now able to take most corners at speeds of what I'd take in my car (Mustang with a low profile and tight suspension); about 10-15 mph over the posted curve speed. Do bikes normally take curves faster than cars?

3.) What about gravel? Is this something I should desperately try and reduce speed for if I can do so safely? Gravel has nearly killed me on a bicycle with racing tires; does it work the same way for sports bikes?

[RayOSV]

1. for a constant radius, on camber curve, outside/inside/outside usually works well. When someone talks about "following the line", they mean following a good line through the turn not necessarily the painted line. Throw in some incline to the road, visibility issues, or decreasing radius turns and the best "line" may be ouside/outside/inside or something else.

2. a well set-up cage can take corners faster than an average bike (max cornering G forces). Riders tend to be more aggressive through turns and go faster than most cages. Many riders take curves at 2X or even 3X the posted (yellow) speed signs. 2X is usually my limit.

3. Gravel is a curse as it can drastically reduce traction and can appear on any road without warning. It's not so much the need to reduce speed as reduce lean angle. The lateral forces don't mix well with reduced lateral grip. That's why it's best to never outride your ability to see road conditions. You're much less likely to be surprised by gravel (or an RV making a U-turn or a freezer) in the middle of the road through a blind turn.

[Fargin_Bastige]

Originally Posted by GoIllini

I have a few questions about curves:

1.) The MSF teaches "Outside-inside-outside" curves, but folks on here talk about "following the line." Is this different? Does it mean that if I enter the curve 2 ft from the median line, I stay 2 ft from the median line through the curve?

Honestly, the MSF advice is the best to follow at this point. The concern with "lines" are spillover from the track folks. On the street, just focus on making it through the turn safely. Worry about your lines when you get on track.

Originally Posted by GoIllini

2.) I'm now able to take most corners at speeds of what I'd take in my car (Mustang with a low profile and tight suspension); about 10-15 mph over the posted curve speed. Do bikes normally take curves faster than cars?

Bikes get in and out of corners faster, so yes they often are faster than cars in corners. Someone will argue this point with me, but this has been discussed on here before and production bikes are faster around corners than production cars. F1 and open wheel are a whole different matter.

Originally Posted by GoIllini

3.) What about gravel? Is this something I should desperately try and reduce speed for if I can do so safely? Gravel has nearly killed me on a bicycle with racing tires; does it work the same way for sports bikes?

Yep, gravel is not a good thing. I crashed on gravel turning left on a street where they had torn open the mouth of the road and not put up an construction signs nor did the street have any lights.

I wound up sliding down the road, with my GSXR sliding down the road in front of me.

So, approach gravel carefully and as upright as possible.

[invision]

gravel, sand, anything not hard-packed asphalt isnt your friend.

[kevinwilly]

"the line" is usually the path you would take to get through the corner the fastest.

A good line will get you through the corner faster than a bad one.


out-in-out cornering is a generally good rule. Ray's comments on that were good.


Obviously, out-in-out is not the shortest distance through a curve. It's the way to get the biggest radius out of the stretch of road that you have. THUS, you can carry more speed through the corner.

But more speed does not always mean the fastest time through the corner. Especially if there is anther corner right after that one, or it is a decreasing radius corner, or off camber.... you have to adjust accordingly.

But these are all things for the track. On the street, you should leave enough room for yourself to shift both ways in the lane in case of something in the road or gravel or something like that. You don't EVER want to be right at the edge of your lane, because you have no place to go if you need to.

[GoIllini]

Originally Posted by RayOSV

1. for a constant radius, on camber curve, outside/inside/outside usually works well. When someone talks about "following the line", they mean following a good line through the turn not necessarily the painted line. Throw in some incline to the road, visibility issues, or decreasing radius turns and the best "line" may be ouside/outside/inside or something else.

What's the process for finding this good line, and how does this work?

Normally, I'm used to relying on my muscles remembering how to handle everything for me, but this seems a bit more active. For an experienced sportbiker, is it more along the lines of your brain figuring out exactly where the bike's going to go ahead of time and you following it?

In other words, could you go through the turn imagining that there's this fixed yellow line- sort of like the first down line on ESPN- that you're following? Or is it more along the lines of just setting up the turn right so you can get through it quickly, and letting the bike go where you need it to go?

2. a well set-up cage can take corners faster than an average bike (max cornering G forces). Riders tend to be more aggressive through turns and go faster than most cages. Many riders take curves at 2X or even 3X the posted (yellow) speed signs. 2X is usually my limit.

If I'm hearing you right, you're able to take 35 mph turns at 70 mph? That's pretty impressive. I had always figured that I would slide off the road if I went more than about 25 mph over the posted speed.

Honestly, the MSF advice is the best to follow at this point. The concern with "lines" are spillover from the track folks. On the street, just focus on making it through the turn safely. Worry about your lines when you get on track.

Out of curiosity, if one were thinking of heading in the direction of the track, is there a different progression you'd recommend for them than someone interested in riding on the street? Or is this something us newbies won't have to worry about for several years?

[RayOSV]

Originally Posted by GoIllini

What's the process for finding this good line, and how does this work?

This is what racers do to earn the big $$. For them the best line is the path that gets them around the track the fastest. They walk the track to check turns, elevations etc. Then they take numerous practice laps to get braking points, speeds, and lines set in their minds. Then the goal is to be consistent but fine tune the plan as needed. Twist of the Wrist (1 not 2) has a lot of info on lines through corners for the track. Some of this will carry over to the street, but remember that you only get half the road width.

Originally Posted by GoIllini

Normally, I'm used to relying on my muscles remembering how to handle everything for me, but this seems a bit more active. For an experienced sportbiker, is it more along the lines of your brain figuring out exactly where the bike's going to go ahead of time and you following it?

In other words, could you go through the turn imagining that there's this fixed yellow line- sort of like the first down line on ESPN- that you're following? Or is it more along the lines of just setting up the turn right so you can get through it quickly, and letting the bike go where you need it to go?

On the street, it depends on whether you are familiar with the road or not. If you know the road well, you can ride it more from memory (this curve is marked at 25 even though it doesn't look bad because the radius decreases just out of sight so use a double-apex strategy). If you don't know the road well, you rely on visual cues to determine what you think will be the best (not necessarily fastest) way through the turn. Corner entry speeds are also determined "on-the-fly". This gets easier with practice. It just isn't safe to ride at track speeds on the street. Too many variables even on roads you know well.

Originally Posted by GoIllini

If I'm hearing you right, you're able to take 35 mph turns at 70 mph? That's pretty impressive. I had always figured that I would slide off the road if I went more than about 25 mph over the posted speed.

Note that I said that 2X is my limit. Long ago when I had a summer job working for the state of CA, I learned where the yellow curve limit numbers come from. State cars with really crappy suspension. In other parts of the country weather (snow, ice) may be factored in.

Finally, don't over-analyze all this. Just ride safely, accumulate miles, and the experience will come with time.

[kevinwilly]

Hey Illini, you up for meeting some place next weekend or something? I am only about an hour from you, and need to do some shopping anyways. If you're going to be around Champaign, let me know, we can go riding, and i'll let you pick my brain about all this...

[Fargin_Bastige]

Originally Posted by GoIllini

Out of curiosity, if one were thinking of heading in the direction of the track, is there a different progression you'd recommend for them than someone interested in riding on the street? Or is this something us newbies won't have to worry about for several years?

I would recommend track schooling and small bike riding. Learning how to ride the chassis and not the motor.

In other words, learning to go fast through technique and not power.

I will say though that a track day doesn't count, in my mind. Racing is a whole other ballgame. So, take a track accredited school (research what CCS and WERA will accept for licensing) and take a school first.

If you are looking for a bike size, the best racers in the world all started on smaller bikes. 80cc and under.

[GoIllini]

Originally Posted by RayOSV

This is what racers do to earn the big $$. For them the best line is the path that gets them around the track the fastest. They walk the track to check turns, elevations etc. Then they take numerous practice laps to get braking points, speeds, and lines set in their minds. Then the goal is to be consistent but fine tune the plan as needed. Twist of the Wrist (1 not 2) has a lot of info on lines through corners for the track. Some of this will carry over to the street, but remember that you only get half the road width.


On the street, it depends on whether you are familiar with the road or not. If you know the road well, you can ride it more from memory (this curve is marked at 25 even though it doesn't look bad because the radius decreases just out of sight so use a double-apex strategy). If you don't know the road well, you rely on visual cues to determine what you think will be the best (not necessarily fastest) way through the turn. Corner entry speeds are also determined "on-the-fly". This gets easier with practice. It just isn't safe to ride at track speeds on the street. Too many variables even on roads you know well.


Note that I said that 2X is my limit. Long ago when I had a summer job working for the state of CA, I learned where the yellow curve limit numbers come from. State cars with really crappy suspension. In other parts of the country weather (snow, ice) may be factored in.

Finally, don't over-analyze all this. Just ride safely, accumulate miles, and the experience will come with time.

Thanks for that great advice. It's starting to make a little more sense, now. Us Engineers can't stop analyzing stuff, but at the same time, it's nice to know that this'll just get better/easier with experience.

I would recommend track schooling and small bike riding. Learning how to ride the chassis and not the motor.

Out of curiosity, how much street experience would you recommend before going to track school?

If you are looking for a bike size, the best racers in the world all started on smaller bikes. 80cc and under.

Would I be the oldest person on the track riding an 80cc?