Steering ABC's

[Way2Fast]

Lets take a closer look at the steering problems that affect many Spyders. The Spyder doesn't have a steering wheel like an automobile, it has a handlebar like a motorcycle, snowmobile, PWC or bicycle. The direction that the handlebar is turned determines where the vehicle will go. The Spyder's power steering or DPS can only assist the turning of the handlebar. It can not turn the bar by itself. In all the cases where Spyder owners have reported that the vehicle changes lanes by pulling to the right or left...something other than the DPS has to be responsible for making the vehicle change direction. Once the vehicle starts to pull right or left, any corrections taken by the operator seem to be hindered by a locking or stiffness in the steering, forcing the operator to over steer and over correct, making the vehicle dart in the opposite direction. This is no doubt caused by a DPS malfunction, but the initial lane change is not. What is making the Spyder change direction in the first place? To my knowledge, no Spyders have excessive play in their steering. It has to be something that puts a drag on either of the front wheels...but only on one of the wheels. The most likely cause would be a dragging front brake on one wheel. The severity of the pulling would be dependent on how much brake is being applied to that wheel. The vehicles Stability Control has the means built into it's computer to apply braking force to any wheel when it determines that doing so will prevent a loss of control. A Stability control malfunction might be the cause.

Of course there is also a possibility that the steering problems are caused by it's mechanical design. The linkage could be binding in some way. Regardless, on a Spyder with proper alignment, the direction the handlebar is pointed is the sole indication of what direction the vehicle will go.

 

[Firefly]

I just don't think the VSS has anything to do with this.

Since you have your DPS disconnected - you should still have problems if your theory is correct.

You could hook your DPS back up and disconnect the VSS if you really want to test the theory--- but I don't recommend it!

It doesn't take many degrees of turn to make the Spyder shift lanes while at speed - something the DPS very well may be able to do on its own. Someone posted watching their handlebar turn all on its own--- while sitting STILL.:yikes:

The first software update had a lot to do with the system not 'centering' and then misreading rider input and possibly 'assisting' in the wrong direction - then causing the 'binding' feeling when the rider trys to correct.


The VSS and brake technology is Bosch and is a proven technology.

I know you said you didn't notice a difference between your DPS turned off and another Spyder with theirs turned on --- which makes me wonder if the other one was working properly.

Park a Spyder (with working DPS) on a smooth garage floor and do the following:

Leave the bike off and turn the handlebar. Notice the feel.

Turn the bike on - let it idle for 30 seconds and leave it on and turn the handlebar. Notice the difference.

I've done this plenty of times and the difference is day and night.

 

[Way2Fast]

Sounds like a case for Ghost Busters to me :shocked:

 

[Way2Fast]

I don't have a second Spyder to compare it to, but I can say that with the engine off on my Spyder the handlebars were a breeze to turn lock to lock while parked in my garage. Ditto when the engine was on. If it were any easier to steer I could see it "wandering" when out on the road.

 

[BillGargan]

I believe it is important to remember that the steering is a type of variable power assist.

It is designed to provide the most assist while stopped -- and the assist reduces in some changing curve that relates to your speed.

I expect that the power assist is none or next to it when going faster than 40 or 50 or so. Certainly at some speed it is simply not needed and would cause the steering to feel too twitchy.

None of this explains the issue that a few folks are having.

 

[Firefly]

I believe it is important to remember that the steering is a type of variable power assist.

It is designed to provide the most assist while stopped -- and the assist reduces in some changing curve that relates to your speed.

I expect that the power assist is none or next to it when going faster than 40 or 50 or so. Certainly at some speed it is simply not needed and would cause the steering to feel too twitchy.

None of this explains the issue that a few folks are having.

:agree:

The faster you go - the less it helps. If it was getting a bad signal at higher speeds then I could see strange things happening. You wouldn't want the power steering on at such high speeds---- things could get squirrley very fast.

 

[stgilmer]

Park a Spyder (with working DPS) on a smooth garage floor and do the following:

Leave the bike off and turn the handlebar. Notice the feel.

Turn the bike on - let it idle for 30 seconds and leave it on and turn the handlebar. Notice the difference.

I've done this plenty of times and the difference is day and night.

Never actually done this til just a few minutes ago.:agree: Huge difference. Good test to do before rides. Thanks Firefly.:thumbup:

 

[Longlegs]

I have experienced the steering malfunction. And I don't think it has any thing to do with the brakes. Why do you say the power steering can't turn the handlebars by themselves? If you are still having trouble with yours why don't you get it to the dealer? The more these are at dealers with this problem the better brp will be able to coorelate problems.

 

[Zerocool]

The most likely cause would be a dragging front brake on one wheel. The severity of the pulling would be dependent on how much brake is being applied to that wheel. The vehicles Stability Control has the means built into it's computer to apply braking force to any wheel when it determines that doing so will prevent a loss of control.

You present an interesting scenario, one which I've thought about recently too. I travel I95 through CT, and the tarmac has been grooved (unevenly) by 18-wheelers tires due to their excessive weight. The center is higher than the sunken area created by the tires. My PT Cruiser has a hard time handling properly in some of these tracks, since they're not symmetrically formed.

So, back to your suggestion above. What would we experience on the Spyder if the rear tire is on the center hump in the lane, the front tires are riding in the sunken grooves, and you travel through a groove that is deeper on one side which raises a tire (momentarily) off the ground? This would cause the system to detect a tire spinning out of sync, which may cause the braking you suggest, no? :dontknow:

Maybe you're on to something worth observing.

Just a thought.

 

[Zerocool]

The braking would be accompanied by an immediate reduction in engine output..... You'd know for sure if it was happening.....

:agree: Would that behavior be experienced as pull to the left or right?

 

[Way2Fast]

The braking would be accompanied by an immediate reduction in engine output..... You'd know for sure if it was happening.....

Only if the VSS is working the way it was designed to. If it isn't it could possibly drag a brake without cutting the engines output. The brake drag might just be enought to make the Spyder change lanes but not enough to noticably slow it down. At any rate, what would the driver do immediately when he notices the Spyder start to go into oncoming traffic? I hit my brakes and tried to steer it back into my lane.

 

[Way2Fast]

:agree: Would that behavior be experienced as pull to the left or right?

Depends on which front wheel brake is being applied. Right front wheel = pull to right, left front wheel = pull to to th left.

 

[Way2Fast]

You present an interesting scenario, one which I've thought about recently too. I travel I95 through CT, and the tarmac has been grooved (unevenly) by 18-wheelers tires due to their excessive weight. The center is higher than the sunken area created by the tires. My PT Cruiser has a hard time handling properly in some of these tracks, since they're not symmetrically formed.

So, back to your suggestion above. What would we experience on the Spyder if the rear tire is on the center hump in the lane, the front tires are riding in the sunken grooves, and you travel through a groove that is deeper on one side which raises a tire (momentarily) off the ground? This would cause the system to detect a tire spinning out of sync, which may cause the braking you suggest, no? :dontknow:

Maybe you're on to something worth observing.

Just a thought.

It possibly could. But it appears that many who experienced this behavior were riding on a straight well paved and level road. The road I experienced it on was level but it did show a little wear where a vehicles tire tracks would be and was slightly higher in the middle.

 

[Way2Fast]

I have experienced the steering malfunction. And I don't think it has any thing to do with the brakes. Why do you say the power steering can't turn the handlebars by themselves? If you are still having trouble with yours why don't you get it to the dealer? The more these are at dealers with this problem the better brp will be able to coorelate problems.

The power steering is only an assist to the steering. I can't see how it could be responsible for actually steering the vehicle...but then with todays crazy computers, who knows what can happen....I bet even the engineers who design this stuff are not totally aware of what a malfunction could lead to.

 

[mike3069]

The braking would be accompanied by an immediate reduction in engine output..... You'd know for sure if it was happening.....

Actually not true. I've been under power in a corner and had the nanny use the brake on the outside wheel, to the point the brakes will smoke, without any interruption to the engine power, not once but many times. It is not required that a wheel lift for this to happen, only that there is enough force on the accelerometer to trigger the braking. The engine cutting out seems to happen only when the rear tire is about to break free from the turning and accelerating forces combined begining to exceed the available traction (the old traction circle from my racing days in play again).

When this happens you must hold extra pressure on the bars to maintain the turn. This could easily be percevied as the bike trying to turn in the opposite direction of the turn if you don't understand what is happening.

 

[Zerocool]

Depends on which front wheel brake is being applied. Right front wheel = pull to right, left front wheel = pull to to th left.

Ah, stupid phrasing of that question on my part. I meant would that account for the pull in either direction? Not whether the pull would go to the left or right.

 

[mike3069]

If it were braking, yes it would pull......But without the accompanying reduction in engine power, it probably isn't a VSS issue......

See my post above. IMHO it could be a VSS issue.

 

[Zerocool]

It is not required that a wheel lift for this to happen, only that there is enough force on the accelerometer to trigger the braking.

So, if what you say is accurate (no reason to doubt you) then a slick foreign substance on the road, or uneven surface, may cause the brakes to kick in, which could explain the feeling of losing/erratic control.

I'm confident the engineers at BRP are exploring all avenues. I'm not one to speculate, but I am an engineer and find observing the threads here very interesting at times.

 

[Smylinacha]

I love all the opinions on this. I don't know what would explain the "click" or "pop" I heard and felt when I tried to stop it from steering to the right when it locked. It clicked or popped is a better word when I got the bars back to center.

HDX road it to the dealer tonight - road the snot out of it and couldn't repeat what happened to me. I'm hoping the tech might find something.

 

[mike3069]

So, if what you say is accurate (no reason to doubt you) then a slick foreign substance on the road, or uneven surface, may cause the brakes to kick in, which could explain the feeling of losing/erratic control.

I don't think so. Only side forces that exceed the accelerometer trigger point will cause the nanny to brake the outside wheel only. Therefor, it would NOT happen in a straight line situation or be caused by rough roads alone. If you were under braking, the ABS would let off the brake on the slippery side momentarily however.