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docmike



Joined: 27 Jan 2005
Posts: 630
Location: Eastern NC

PostPosted: Wed Mar 02, 2005 1:41 pm    Post subject: Technique Reply with quote

We have spent a lot of time talking about CHS, trail, caster, camber, toein, shocks, swaybars, and other hardware issues here, but have never discussed how do you go around a corner. Question



Do you use the late apex line like all the cycle magazines claim the sport bikes should use?

Do you clip the apex like a sports car?

Do you barrel in full blast, nail the brakes, square it off and peg the throttle?

Do you hang off like the sidecar manual says you should?

What about the front brake and throttle at the same time to increase rear tire slip in right handers?

Or do you just ride?
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93 BMW K1100RS / EML Speed 2000
89 Honda GB 500 (6,700 miles, all original except tires)
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legalr



Joined: 30 Jan 2005
Posts: 163
Location: Wallingford, Vermont

PostPosted: Wed Mar 02, 2005 4:29 pm    Post subject: Technique and Other Things. Reply with quote

Mike says:
Quote:
[We] have never discussed how do you go around a corner.
Do you use the late apex line like all the cycle magazines claim the sport bikes should use?

Do you clip the apex like a sports car?

Do you barrel in full blast, nail the brakes, square it off and peg the throttle?

Do you hang off like the sidecar manual says you should?

What about the front brake and throttle at the same time to increase rear tire slip in right handers?

Or do you just ride?


Very good questions, Mike! As a recent convert to sidecars I want to know what the others on this forum have to say too. I did see that a sidecar manual claims that late apex = larger radius = more traction.

But without taking over your discussion what has always plagued me is sharp right-handers and what to do if your wheel lifts. Unfortunately I don't think there is a consensus. I find some contradictions among the "knowledgeable" especially when it comes to "steering reversions."

One manual says in one breath that, "if the sidecar wheel lifts off the ground, the outfit suddenly becomes a two-wheeler, (at least for purposing of steering)." Then a few sentences later says, "If the sidecar wheel just bounces in the air for a second or two, it will thump back to the pavement before the driver realizes there was a steering reversioin. There is just the strange feeling that something was temporarily wrong with the steering." And then, a few more sentences later the manual says, "What's important ot recognize that once the car is flying, the rig is balanced and steered by countersteering."

Perhaps I am dead wrong, and I will readily admit that I am a sidecar novice, but I think these sentences may be true or have some validity in isolation but that they convey false information, and here's why.

My experience is that you don't countersteer the instant the sidecar wheel lifts. I think you continue to steer and control it as a sidecar with direct steering until it either comes back down on three wheels or it lifts high enough to reach what I call the point of equilibrium [point of balance] and at that point countersteering become applicable. If I'm dead wrong, have at me!

I also disagree with the statement that, "What's important to recognize is that once the car is flying, the rig is balanced and steered by countersteering." I think that the rig is not balanced as soon as the chair comes off the ground. It is not balanced and steered by countersteering until it reaches the point of balance. Coming off the pavement is not automatically equivalent to being balanced. If I'm dead wrong, have at me.

Personally, I found the manual very confusing and only after what some might call a near-death experience and some time in my mowed field with cones did I come to reject what I had read.

That brings up what to do after your wheel comes off the ground? I try to avoid that situation by using a lot of ballast and moving my center of mass [hanging off] to the inside of the turn if I think it looks sharp or off camber or is a decreasing radius.

But if I miscalculate and can't avoid a lifting wheel I will decrease my speed, or roll on the throttle and apply some front brake at the same time. I know that application of throttle and front brake is an accepted modality but the reason I believe that decreasing my speed will help bring my wheel down is that the centrifugal force that caused it to rise off the pavement was a product of speed + mass + radius of the turn. So if I decrease any of those components I will lessen the centrifugal force and that will cause my wheel to come down. I can't change the mass of my outfit in mid turn nor can I change the radius for all practical purposes but I can reduce the speed of my outfit slightly and maintain control. Speed is a component of centrifugal force. If I haven't been driving like a bat out of Hell reduction of just a small amount of centrifugal force should bring my sidecar wheel back down to the pavement.

So what say you? Am I all wet on this one?

Question
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Thu Mar 03, 2005 12:21 am    Post subject: Reply with quote

Larry you are totally correct on your view of steering reversion. It does not occur as soon as the tire leaves the ground. Nope..Nada..don't happen and you experienced in your near crash what others have experienced from reading that fable!
The rest of what you wrote is pretty much right one. If you are new to these things you are learning well even though you found out the hard way that all that is written is not true.
IMHO taking a late apex is a good thing. It allows you to see through the corner futher, brake later and keep from swinging wide on the exit. If one goes in too low and finds that the corner is a decreasing radius deal he may be in the pucker mode on the exit if not worse. Crossing the centerline IF NOT ON PURPOSE on exit is a bad thing. Not only due to that on coming truck but due to the fact that many times the camber of the road will change to an off camber situation..yee haa.
This , hopefully, will be an interesting thread so I will not ramble any more for now.(And everyone said..GOOD.. Laughing )
Claude
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Thu Mar 03, 2005 12:32 am    Post subject: Reply with quote

Mike wrote:
>>[We] have never discussed how do you go around a corner.
Do you use the late apex line like all the cycle magazines claim the sport bikes should use?<<

If possible yes.

Mike wrote:
>Do you clip the apex like a sports car?<<

Only if you know there is not a culvert at that point..LOL.
Seriously it depends on the road. In hard twisties it is tempting to straighten out the curves. This is fine if the raod is not hevily banked. If on a hard twisting road with high banking it is usually faster and even safer to follow the road so to speak. The reson for this is if get out of sinc with the banking transition points then we are going over the humps from turn to turn and the suspension gets confused beinglaoded and unloaded at the wrong points. This may not make sense unless you have been ther and done that on a tight twistie banked road (The Gap is a pretty good example in places)

Mike wrote:
>>Do you barrel in full blast, nail the brakes, square it off and peg the throttle?<<

can be done on the right rig. Not sure abou these HPS jobies with all the rubber thay have on the ground.

Mike wrote:
>>Do you hang off like the sidecar manual says you should?<<

THE MANUAL? Whatever! Not too often. Plus it can get you in trouble if done while already in a turn.

Mike wrote:
>>What about the front brake and throttle at the same time to increase rear tire slip in right handers?<<

Yep

Mike wrote:
>>>Or do you just ride?<<<

Yep

Just my opinions of course,
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Claude Stanley

Founder: Internet Sidecar Owners Klub
http://autos.groups.yahoo.com/group/SCT/

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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hal



Joined: 03 Mar 2005
Posts: 4
Location: Houston, TX

PostPosted: Thu Mar 03, 2005 1:48 am    Post subject: Reply with quote

Before getting into flying the sidecar wheel one must first go back to basics and consider centrifugal force and where it acts and how it acts. It acts as a force, not at the tire/road surface, but at as a point force acting on the center of mass or gravity, typically about 15 inches above the road surface. This is resisted by the restoring force of the weight of the rig plus driver and passenger acting again thru the CoG about 15 to 18 inches to the right of line between the front and rear wheels of the bike. You take moments about this rollover line or tippover line. How high the sidecar wheel is or is not is of no consequence, regardless of what any silly book says.

Your sidecar rig is a two track vehicle. Like a truck you must steer it HARD to make it turn. Only if you can "balance" it like a bicycle and convert it into a single track vehicle can you countersteer it. That is very difficult to do. Yes, it can be done. You can also countersteer a pickup truck if you try very hard, but why would you want to do that?

In a rash moment of clarity I had a brilliant flash of inspiration. As long as you are turning to the right (with the sidecar wheel in the air) you are in a normal hard steering mode (ie, not in a countersteering mode or in a steering reversion mode) if the sidecar wheel does not come up any higher, no matter how high the sidecar wheel is at the time! Any attempt to bring the sidecar wheel down by "pushing on the right handle bar" will cause the rig to physically turn to the left as it is being controlled by normal hard steering and not by countersteering.

The only time countersteering can be obtained on a sidecar rig is when the overturning moment exactly balances the restoring moment and the rig is proceeding in a straight line, ie, it is NOT proceeding in a circular path. Then and only then can steering reversion occur. Once in this position it is then possible to carefully proceed to countersteer to the left or to the right using steering reverion techniques, but not as long as one is still proceeding in a curved path.

Also, the Yellow book teaches you must be a gymnast. Not true. No need to be a marble stone, but you do not need to have a full morning workout either.

Books on sidecaring are available free at:
http://www.sidecar.com/links3.asp

Hal Kendall
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Ralph



Joined: 27 Jan 2005
Posts: 591
Location: Lexington, Ky

PostPosted: Thu Mar 03, 2005 2:06 am    Post subject: Reply with quote

[quote]We have spent a lot of time talking about CHS, trail, caster, camber, toein, shocks, swaybars, and other hardware issues here, but have never discussed how do you go around a corner. [quote]

Follow us Cool Hehehe it has worked for me all but once. The leearning curve. Cool
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swaybar2002



Joined: 26 Jan 2005
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Location: Central Pa.

PostPosted: Thu Mar 03, 2005 2:18 am    Post subject: Reply with quote

Thank God for trees Ralph Big Grin
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Claude Stanley

Founder: Internet Sidecar Owners Klub
http://autos.groups.yahoo.com/group/SCT/

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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zentime



Joined: 22 Jan 2005
Posts: 833
Location: Massachusetts USA

PostPosted: Thu Mar 03, 2005 3:53 am    Post subject: Re: Technique Reply with quote

docmike wrote:
We have spent a lot of time talking about CHS, trail, caster, camber, toein, shocks, swaybars, and other hardware issues here, but have never discussed how do you go around a corner. Question



Do you use the late apex line like all the cycle magazines claim the sport bikes should use?

Do you clip the apex like a sports car?

Do you barrel in full blast, nail the brakes, square it off and peg the throttle?

Do you hang off like the sidecar manual says you should?

What about the front brake and throttle at the same time to increase rear tire slip in right handers?

Or do you just ride?


Mike, that's a bunch of questions. I had to think about it but it's an Interesting intellectual exercise. I drive pretty much by instinct and don't really analyze what it is that I do but I'll give it a shot. I think the way I drive is closely related to my racing days in that I look for the inside line. Just to check myself I googled Apex and I don't think that's what I do. As it was explained in "hitting the apex" that it is also the "slow in and fast out" "good" approach which as explained is the preferred way in that you can get on it sooner and have a longer straight away which arguably will get you around the track faster. Given the very effective brakes I and most of us have on our rigs, late braking is not a problem. I like going to the inside of a corner because it gives me some room to work with coming out of the corner if I start drifting or sliding to the outside of the turn. I like to go to the inside and getting back on it early. I think this is why it so tedious to ride with solo bikes in the tight stuff. Frequently we can brake later than most average solo riders.
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Thu Mar 03, 2005 4:21 am    Post subject: Reply with quote

Glad to see you post on this Bill. Many racers go slow because they try to go too fast. What I mean is that if one gets into a corner over his head and has to go through a lot of gyrations to recover he will come off the turn a lot slower than one who goes in a little easier and nails it sooner. We used to speak of slowing down to go fast and this is a typical case of that. I don't know what kind of racing you did but this is true in so many types of racing especially on pavement.
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Claude Stanley

Founder: Internet Sidecar Owners Klub
http://autos.groups.yahoo.com/group/SCT/

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Thu Mar 03, 2005 4:28 am    Post subject: Reply with quote

With a well setup HPS rig do you all tend to break the front tire loose coming off a turn more so than the rear? Is there a big issue related to this in right handers -vs- left handers ?
Claude
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Claude Stanley

Founder: Internet Sidecar Owners Klub
http://autos.groups.yahoo.com/group/SCT/

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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zentime



Joined: 22 Jan 2005
Posts: 833
Location: Massachusetts USA

PostPosted: Thu Mar 03, 2005 5:03 am    Post subject: Reply with quote

Larry and Hal, great writing. I'm afraid you guys have given the topic of countersteering as it applies in the sidecar world substantially more thought than I have. I'm going to print out what you guys have said and try to absorb it a bit more thoroughly and comment if I can respond intelligently. It would be interesting to hear from others on this issue. Mike, Paul,................?

As I responded to Mike, they way I drive a sidecar is mostly instinctive for me. I've been driving sidecars for so long and in so may different settings, it seems I just do it. Much like walking or going for a ride in the car. As another example, typing, spelling and composition are much more difficult for me in that I have to think and be deliberate about the whole process, where driving a sidecar is intuitive. I think the same is true for many of us here so it's difficult to verbalize much about technique when you're accustomed to "just doing it"

I will say this much. Obviously the potential for the sidecar wheels to come up is an issue all sidecarist need to be aware of and understand how to deal with it. I see it as a novelty sort of thing when done deliberatly and perhaps purposely doing it in order to learn how to deal with it. Beyond that the objective is to keep the wheel on the ground. I won't say never but having the sidecar wheel lift is not a huge issue for me. In my case I think it's technique, the overall setup of my rig and for sure the anti swaybar. I also never do any serious riding with a passenger on the back and the sidecar empty. If I don't have a passenger, I always have extra weight in the sidecar. In high performance sidecar driving I find brake fade and the limits of traction on the front-end to be much more limiting factors than any concern of the sidecar wheel lifting.
Thanks again Larry and Hal for the stimulating posts
bill
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zentime



Joined: 22 Jan 2005
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PostPosted: Thu Mar 03, 2005 5:09 am    Post subject: Reply with quote

swaybar2002 wrote:
With a well setup HPS rig do you all tend to break the front tire loose coming off a turn more so than the rear? Is there a big issue related to this in right handers -vs- left handers ?
Claude


for me, it's an issue in hot lefts. I offset it by trying to get my weight over the front end. It's one of the reason most of us run low tire pressure. To get a bit more bite, I run 20 to 22lbs all around.
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hal



Joined: 03 Mar 2005
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Location: Houston, TX

PostPosted: Thu Mar 03, 2005 6:23 am    Post subject: Reply with quote

To recap, the technique I mentioned for righthanders was the traditional overturning moment vs restoring moment in a dynamic situation given that everything was balanced and that the entire force load was being resisted by the front and rear tires. However, that is not true for normal old fashioned racing techniques that existed long before the term HPS was in our idiom. To gain better control we did things like set our machines up before the turn - like apply some braking force to the sodecar wheel only - works as long as the sidecar wheel in weight heavy - or we feathered the front brake slightly - helps to give us a little more traction change - or we applied a bit more throttle to give us more power output to the rear wheel to help drive us through - or we had our monkey hang out over the sidecar wheel and hang his head over the green for added weight shift - or we dropped down a gear or two and twisted the throttle to the red line to break the rear wheel loose and really drive the son of a bitch through the curve - depending upon just how seriously we wanted to get around the damn corner, how fast were we going, and what kind of a rig we were on, and what communication we had with our monkey.

Typically, in full race mode, cornering is very nearly damn near flat with perhaps just a minor lift of the sidecar wheel so the talk of countersteering with a HPS rig is really absurd. But it can happen. Seriously, if you really want to experience it, remove the body and just practice flyong the chair with just the sidecar wheel on an outrigger stalk. It will come up at a walking speed and you will have lots of fun safely and learn quite a lot.

However, the very same forces that will cause the sidecar to lift on a righthander also apply equally on a lefthander - but with a BIG difference. Here the tippover line is between the front wheel and the sidecar wheel. Normally, this is much more stable - however - the same forces still apply, and when things go wrong they happen much quicker on a lefthander than on a righthander. On a righthander the sidecar comes up slowly. On a lefthander the sidecar nose punches the ground while the rear wheel comes up faster than you can wipe your nose. Has happened to me and to many of your pals. Usually, either the upset stops with the nose punched down and skids, or the rig sumersaults completely over. You went into the corner too fast and the tires gripped instead of slipping.

The basic equation for centrifugal force is F = m V x V / r; and it acts at the height h where h is the height for the center of gravity above the ground. The overturning moment is the force x h so as you get you rig lower to the ground so you get a lower overturning moment.

The restoring moment is the weight times the distance the center of gravity is from the line between the front and your rear wheels. The restoring moment is the weight times this distance d. By getting your rig wider you get a bigger restoring moment.

So - by making your rigs lower and wider you get a more stable rig - but then - you knew that already without me telling you anyway - goodnight.

Hal Kendall
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legalr



Joined: 30 Jan 2005
Posts: 163
Location: Wallingford, Vermont

PostPosted: Thu Mar 03, 2005 12:02 pm    Post subject: Technique and Other Things. Reply with quote

Bill said:
Quote:
(The way) I drive a sidecar is mostly instinctive for me. I've been driving sidecars for so long and in so may different settings, it seems I just do it. Much like walking or going for a ride in the car. * * * I will say this much. Obviously the potential for the sidecar wheels to come up is an issue all sidecarist need to be aware of and understand how to deal with it. I see it as a novelty sort of thing when done deliberatly and perhaps purposely doing it in order to learn how to deal with it. Beyond that the objective is to keep the wheel on the ground. I won't say never but having the sidecar wheel lift is not a huge issue for me. In my case I think it's technique, the overall setup of my rig and for sure the anti swaybar. I also never do any serious riding with a passenger on the back and the sidecar empty. If I don't have a passenger, I always have extra weight in the sidecar.


Reassuring comments, Bill. My goal is to become an instinctive driver too and I agree with your admonition to keep extra weight in an empty sidecar. I don't have an anti sway [yet] and if that really helps keep the third wheel on the ground it's just one more reason for me to have one installed.

I liked Hal's comment that
Quote:
Only if you can "balance" it like a bicycle and convert it into a single track vehicle can you countersteer it. That is very difficult to do. Yes, it can be done. You can also countersteer a pickup truck if you try very hard, but why would you want to do that?

In a rash moment of clarity I had a brilliant flash of inspiration. As long as you are turning to the right (with the sidecar wheel in the air) you are in a normal hard steering mode (ie, not in a countersteering mode or in a steering reversion mode) if the sidecar wheel does not come up any higher, no matter how high the sidecar wheel is at the time! Any attempt to bring the sidecar wheel down by "pushing on the right handle bar" will cause the rig to physically turn to the left as it is being controlled by normal hard steering and not by countersteering.
They reinforced exactly what I learned the hard way. He said it very clearly and my experiences affirm it.

At sidecar school in Virginia three years before I had my unit built, I was able to fly the chair of those light training rigs with no difficulty whatsoever and ride all around the parking lot with the chair "flying", but driving an HP rig is another matter, at least for me. It is wider, heavier, and has flat profile auto tires, all of which combine, in my judgment, to make it more difficult to fly the chair compared to the light narrow rigs at the sidecar school. I have seen photos of a perfectly balanced HP rig under control on two wheels and I know a good friend of mine can do that too, but for me, I think the countersteering thing is overblown. Others may feel differently. My goal is to become an instrictive driver with three wheels on the ground. Cool
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Thu Mar 03, 2005 12:17 pm    Post subject: Reply with quote

Larry wrote:
>>I think the countersteering thing is overblown.<<

Yes I agree Larry. We have seen cases where a rider has felt he should countersteer (turn left to go right) from what he was 'taught' and ended up crossingthe centerline with disasterous results. It is a crying shame. This steering reversion teaching that says reversion happens as soon as the sidecar wheel leaves the ground is simply not true and should not be taught that way. Flying the chair with steering reversion in effect and hard cornering with the sidecar wheel off the ground ARE NOT the same thing.
Hal's statement that if you turn left to correct a sidecar wheel being off the ground and the rig goes to the left is solid proof that no reversion is in effect. Simple.
Claude, not just my opinion but fact.
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