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Cornering Difficulty


agocat
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While cornering I find that to keep the bike on line and not tracking toward the inside of a corner, I need to steer the front tire toward the inside of the corner (the opposite of counterstearing) to prop up the bike. I've tried more speed but it seems to make the bike turn even steeper and tighter :blink: Seems like the bike just wants to flop over and I am unable to achieve that neutral, one hand off of the bars cornering I saw in class. This happens with both of my bikes so I know that it isn't a hardware problem, and is more evident in faster corners.

 

Your help is appreciated...

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There are a lot of factors here that can cause this. What are your two bikes? Have you changed the geometry in any way (front or rear)? Are you using OEM sized tires or larger/smaller?

 

I would immediately key in on a setup problem, but if it's happening on multiple bikes, either you have a bad setup on both bikes, or you're doing something to cause this.

 

When you get into the corner, immediately after you have initiated the turn, get ON the gas. If you're not on the gas, you will continue to transfer weight to the front and tighten up the turning of the bike.

 

Another classic problem is that newer riders tend to early-apex corners because they are freaked out from the speed. This messes up the entrance and exit terribly, but from what you've said this doesn't seem to be the problem...

 

Let me know on the other questions.

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I'm not sure i COMPLETLY understand what your problem is here, but when entering a corner you first countersteer to get the bike leaned over, but once the bike is leaned over and you have some G forces holding you at an angle if you make small steering adjustments with the bars the bike will steer like a car more and not countersteer, but if you make more sudden larger movements it will go back to affecting your lean angle and countersteer again....what i am saying is bikes don't alwayse countersteer and they're not supposed to.....for instance try walking your bike, while you are holding it upright it will have 0 countersteer...so it could be that what you are experiencing is normal and you just have to get used to it...are you a new rider?

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What you describe seems a lot like the change that happens on my Buell after going from a clapped out set of Metzeler M1's to a new set. It doesn't exactly try to fall into the corner of it's own accord, but with the old ones it takes a bit of pressure on the inside bar to keep it leaned over. This is with tires that are used for some commuting and end up a little flat in the middle... I typically swap both my tires out at the same time. Because of this, the rear is typically more worn in the center than the front. replacing both brings the bike back to where the tires profiles match...

 

Now... Extrapolating the detail that causes my Buell to require MORE effort when the rear gets a little flat in the center... Maybe your front has too flat of a profile compared to the rear?

 

What are your tire pressures?

 

What type of tyres?

 

Did you recently change tire brand/model and not adjust for the difference in ride height?

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  • 2 weeks later...

Uuugh! Yes I did read the initial post. Sorry but, the conversation turned towards maybe you've got the wrong tires and that was the best I could come up with. They really are good tires for cornering. The reason I didn't comment on the bike cutting in tight thing is because I sort of have the same problemwith an F4i. I hit 10 degree banked, 30 MPH posted clover loops at 70 and 75 MPH., and I have to hold myself outside( No, I'm not fondeling myself in public.). I'm draggin' knee, peg, my exhaust and dragging a hole in the toe of my boots. (Buying some race boots tomorrow.) Still, I feel I can go faster because if i'm diving to the inside then surely it means I not generating enough centrifugal force to hold me on the outside until I'm ready to dive in to the apex. I have got to get someone to film me. So I know what I look like in a corner. Are you supposed to have to hold it out or should it just be there? In a car the faster the wider. Seems to me on a bike the faster the tighter..... and lower. I've actually scraped my handle bar a couple of times. Backing it in as they say. Sort of a controlled lowside I say. Anyway I'd sure like to discuss this topic further, or have someone discuss it at me anyhow.

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Yes, really!! Perilously close to disaster? Yes, really!! Anyone else ever touched the bike down and brought it back? I've done it five times. Like I said, it's more of a controlled crash than an advanced maneuver. Keith calls it "Hooking it" or something to that effect. Ought to be called "The Pucker Hook"!! I never planned to do it. It just happened and I've been lucky not to crash.

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  • 2 weeks later...

My sincere apologies to you all for my very late reply to your attempts to help me. I've had some severe life difficulties that have distracted me and made things kinda bad around here. Hopefully you'all are still watching this forum string and can give me some feedback.

 

Some answers to your suggestions:

 

JeF4y suggested that I get on the gas right after I countersteer. Also suggested that I may be apexing early. These all sound very reasonable possibilities to me (mucho thanks!). I know that I have trouble trusting the tires. I'll try this (haven't had the time to ride in weeks) and see what I'm doing. Also, I've made no set-up change to the bikes.

 

Supernought wanted to know if I'm a new rider. I've been street riding for 15 years and consider myself a safe and sometimes fast street rider.

 

Fastfreddie wondered if I was continueing to counter steer while leaned over and cornering. I know that I'm not doing that; with as light of a grip as I can have on the bars, I'm actually having to steer into the corner to keep the bike from falling in.

 

 

One thing I learned from reading your responses is that I'm pretty clueless about suspension set-up. I could sure use some advice or be refered to a book or something. In fact, some suggestions regarding some starting set-ups for both bikes would be super helpful. I'm 180 lbs plus another 15-20 lbs of riding gear. Here are all of the specs that I have on my 2 bikes. Again, I appreciate your feedback.

 

1993 Honda F2 track bike

Front tire: Dunlap D 207F GP 120/70 ZR 17 Pressure around 30-33 lbs on the track

Forks have preload adjustment only.

Rear tire: Dunlap D 207 GP 170/60 ZR 17 Pressure around 30-33 lbs on the track

Shock has preload, compression and rebound dampening adjustments (don't really know how they should be set! (@**&)

The bike suspension compresses 25mm in front and 6mm in back when starting with no weight on the suspenion, and then lowering the bike and having the suspension support only the bike's weight. Have no other measurements.

 

1992 Ducati 750 ss street bike (beautiful bike with red body and white frame!)

Front tire: Dunlap D 208 120/60 ZR 17 Pressure around 38-39 lbs for the road.

Forks are Showa upside down and have no adjustments that I can find on the units or in the shop manual.

Rear tire: Dunlap D 208 160/60 ZR 17 Pressure around 38-39 lbs for the road.

Shock has rebound and compression dampening and preload adjustment.

I have no sag measurements on this bike (yes, I now understand that this is BAAAAD)

 

Thanks again everyone for your help!! Super cool to have this tool.

 

Take care...

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I have never ridden a bike that doesn't countersteer and definitely never ridden one that steers the way Supernought says-- turns in like a car. The idea that little corrections are made like car steering and larger ones are from countersteering is a new one on me. I have heard that over 225mph bikes do steer like cars and then return to countersteering past 275 (I think that was the number).

 

I'd like to know where this data came from Supernought. Where?

 

Keith

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Agocat,

 

Your spring sag sounds way out of whack but before changing it you need to measure it correctly. You take the measurement with you on the bike in normal riding position. First you take the meausrement of the front and the rear at full extension, then sit on it and see how much sag its got. There are articles out there on setting spring sag.

 

Here is the address from Race Tech with the directions on how to do it.

 

http://www.triumphnet.com/st/acc/racetech/setup.htm

 

Keith

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As a former, stand-up, steer by your pegs dirt bike rider in the 1960s, I have more recently found it difficult to teach myself how to get a knee-down riding a big Blackbird on the roads -- until I read Keith Cole's TOTW1 and came up with this discovery: "forcing" a knee down while turning was causing my bike to steer into the apex of a corner. The problem being, my cornering speed was not enough to benefit from the weight shift caused by the forced knee-down!

 

For this reason, either I (or perhaps the bike in its own infinite wisdom!) was instinctively "turning-in" toward the apex of a corner in order to counter the weight shift resulting from the forced knee-down. As a result, I have had no other recourse than to either: (1) give-up on the forced knee-downs, or (2) counter steer away from the apex with quick and usually awkward shoves on the outside handle bar. Perhaps, had I had the confidence, increased throttle would have accomplished this same purpose.

 

My new approach to getting knee-downs is to no longer try! I shift my body weight to the inside as usual, but then let my inside knee dangle FREE, which means it no longer comes down UNTIL I reach a cornering speed that actually benefits from the weight shift! More generally, I've learned that I need to stay RELAXED in the saddle -- sort of like a heavy sack of potatoes with shoulders hunched (I'm tall) and arms only lightly on the bars, and (especially) my inside knee LOOSE and NOT reaching for the pavement. When I force the knee downs, it feels like I am trying to remain upright on the pegs of a stationary bike when, in fact, I now know that I need to move before taking my feet off the ground!

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When you get into the corner, immediately after you have initiated the turn, get ON the gas.? If you're not on the gas, you will continue to transfer weight to the front and tighten up the turning of the bike.

I've had the same kind of knee-down problem coming off the dirt and onto the roads, and I totally agree with JeF4y's response to this question on how to correct the problem: you need to have enough speed to benefit from the knee-down! Without the speed, the bike turnes in toward the Apex.

 

I attempted to explain this in my earlier response to this question (above); but JeF4y said it much better. I just missed reading his response before launching my own long-winded response a month later!

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Long winded? Maybe but, very well said! That's it! Eureka! I'm going faster than ever and hardly touching my knees. Don't try to go fast and you will. Relax lika a sak 'o' taters. Trust your tires. (If they're trustworthy) Just, when street riding/racing/practicing, watch out for gravel, antifreeze, oil and the blind decreasing radius'! Yee haaawwww! Excellent info.... as usual. Oh! Almost forgot. I've been getting a "Wavy" action in fast sweepers. Like the beginnings of a tank slapper but, LUCKILY very subtle. Any ideas on which component of the suspension system to liik at?

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When you get into the corner, immediately after you have initiated the turn, get ON the gas. If you're not on the gas, you will continue to transfer weight to the front and tighten up the turning of the bike.

JeF4Y's quote.

 

Not so Jeff, at least not unless you have some pressure on the bars and that is quite unconscious for most riders. When you are off the gas in a corner the contact patch is to the inside of the tire's center and is countersteering the bike upwards and wide in the turn. Going off the gas and transfering weight to the front end with the tiniest bar pressure has a pretty big effect and, again, is quite unconscious for most riders.

 

The one thing that does modify this is the rider's body position. The forward and down position seems to bring in more pro-steer (the front end turning in towards the corner and tightening up the turn) in that position but we have yet to discover if there is bar pressure being applied at the same time. Experiments are on the way and in progress to determine this.

 

I am working with Paul Thede at Race Tech and he is building a really great data acquisition system that includes bar pressure and steering head rotation sensors. We will use the data for the Twist II DVD which we are shooting in October.

 

Keith

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  • 4 weeks later...

Sounds to me like you are setting up for a sharper corner than needed by leaning to much at the entry. Maybe its just too late or im stupid, but from your post you state that it does it on both bikes, and the only problem is that when in a turn you have to correct to less lean for fear of smacking into the apex? If so, just work on hitting your apexs better. Try the same corner a couple times in a row and relax. Start slower, leaner slightly and work your way up. Of course as previously stated, if your turning too much, that means you can be going much faster until your knee is down and your hitting the apex perfectly. Unless of course you need to go slower in a certain corner due to a slower upcoming section.

Ken

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Bingo!!!

 

Just got back from a nice autumn ride in Colorado. I found that I was flopping the bike over super good (at my level 2 class a year ago my coach Jason{?} said that I was best in the class at that). However, I was not getting on the gas right away and/or both my bikes did not have enough power to achieve that balance between lean angle (me flopping down the bike way over) and speed when my corner entrance speed is slower. I found that if I don't lean the bike over as far (for my same corner entrance speed) and focus on getting on the gas, that feeling of tipping into the inside of the corner is gone. Just need to start to increase the corner entrance speed and then can initiate a steeper lean angle.

 

Thanks to everyone for helping me, especially JeF4y and Keith! It's much more fun riding now.

 

Everyone take care...

 

M

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I had the same problem at first. I probably don't know what the hell I'm talking about but here is what I discovered. :blink:

 

1. I was TIPPING TOO MUCH for the amount of speed I had coming into the turns. I found that projecting my torso and shoulders more forward and into the turn enabled me to make turns with much less bike lean.

2. I was LATE ON THE GAS. I found I could stop the tipping by getting on the gas as soon as the tipping action was completed. In a sense it began to feel as if as if I could "catch myself" from falling in any further with the throttle.

3. I was TIPPING TOO SOON and TOO SLOWLY. The fix was simple, REFERENCE POINTS. Wait longer to tip then DO it quickly. It WORKS! :D

 

If you haven't read Keith's Book "Twist of the Wrist II" do it. Its a GREAT book!

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