Temporarily Disable VSS?

[lamarguy]

This subject may have been beat to death but I haven't found an optimal solution yet. :doorag:

I'm seeking a way to temporarily disable the "throttle kill" feature of the VSS when cornering at low speeds or making a sharp turn from a stop. I get embarrassed when I'm only going 10 MPH and the engine sputters when attempting to accelerate out of a turn. pps:

Modifications I've already made to help avoid VSS engagement:

• Set shock dampers to 5.
• Set front tire pressure to 18 PSI and rear tire to 28 PSI.
• Considering a stiffer sway bar.

To temporarily disable VSS (low speeds only), I'm considering:

1. Add a switch to temporarily override the rear sensor signal with the front sensor signal. This appears to be a solution others have tried with success. No negative DPS or ABS effects.
2. Reduce steering angle feedback to the ECU, thus delaying VSS engagement.
3. Close the parking brake sensor circuit (without actually engaging the parking brake). Not sure what this will do, if anything.
4. Close the brake pedal sensor circuit (without actually engaging the brakes) to keep the ECU in ABS-only mode. This looks promising and very simple to implement if it works.

For the record, I'm NOT looking to burn donuts in the street. I simply want to accelerate out of a reasonable turn without the engine cutting out. :thumbup:

For example, you can easily disable the "throttle kill" feature (DTSC) of the stability control system in an AWD Volvo with the press of a button. It still engages the braking system (with YAW sensor input) to keep everything under control but allows power slides. In fact, the only time I leave DTSC on anymore is in the rain or other adverse conditions.

 

[MouthPiece]

My response is not exactly on point, but here it goes. I was having problems with my VSS after having a new corbin seat installed. The VSS was kicking in when I had never experienced it prior to the seat installation.

My dealer tech found that the sensor located under the seat had been installed upside down by the corbin people. He "righted" it and my VSS has not kicked in since. This includes taking some "power turns" as well as riding in the mountains of North Carolina.

Chris PE# 0004

 

[M2Wild]

Now if someone can come out with a plug in like the O2 modifier to replace the seat sensor and modify the VSS so we can do a little donuts ... that would worth a few bucks in my mind.

 

[lamarguy]

I'm trying to avoid the throttle kill as Lamonster demonstrated in the video below:

 

[altonk]

Hold down the brake just enough to engage the switch but not calipers
Works most of the time

 

[altonk]

At low speeds it's all about the steering angle sensor
As soon as you get the bars straight you're good for full throttle

Reverse trikes are very unstable at low speed and large steering angles.

I have a reverse recumbent trike with a 50 cc engine on it. No nanny lol it will go 70+ and the only time I ever rolled it was at low speed with a lot of steering angle. It's center of gravity is much lower than the spyder. The roll over is quick unpredictable and very nonlinear.

I can understand why BRP set the threshold low.
Try carrying more speed into those corners and accelerate as soon as you get the steering straightened

 

[altonk]

If you disable it you'll end up on your head

 

[altonk]

FYI

http://www.rqriley.com/3-wheel.htm

 

[lamarguy]

If you disable it you'll end up on your head

Agreed. I'm not questioning the intent of the stability control (braking individual wheels) to prevent rollovers. However, I am questioning the inability to turn off traction control.

For example, if you're stuck in the snow you'll inevitably get wheel slippage. That's the primary reason cars equipped with traction control have the ability to turn it off.

I'll try the light pressure braking trick and see if the ECU cuts engine power during a slow turn. Thanks for the article link too.

 

[altonk]

It isn't just traction control at low speeds and high steering angles it's easy to roll the trike with power before wheelspin

 

[lamarguy]

Just ran a quick test in a parking lot outside my neighborhood. Closing the brake circuit and/or parking brake circuit does not prevent VSS from cutting engine power.

The primary factor for VSS engagement appears to be steering angle.

 

[Justin]

If you disable it you'll end up on your head

You can whip endless donuts and not land on your head. Taking off you just tail whip and in the rain you can drift curves. ABS and TCS still work also.

 

[boborgera]

Just ran a quick test in a parking lot outside my neighborhood. Closing the brake circuit and/or parking brake circuit does not prevent VSS from cutting engine power.

The primary factor for VSS engagement appears to be steering angle.

When i come out of a parking lot /driveway /side street, I try to Stop in
the direction of the way i want to turn ,at a slight angle. Then then when i gun it the VSS doesn't kick in.
If i try the same turn at a Right angle and gun it the VSS will kick in.
Now that's the way my Spyder reacts, Not all Spyders act the same.
Your right about the steering angle, Maybe that angle can be adjusted'?
so it won't be so sensitive. :dontknow:

 

[lamarguy]

If i try the same turn at a Right angle and gun it the VSS will kick in.
Now that's the way my Spyder reacts, Not all Spyders act the same.

That's how all Spyders react. > 50% steering angle + throttle = engine sputter :sour:

I'd be much happier with > 80% steering angle + throttle = engine sputter

Your right about the steering angle, Maybe that angle can be adjusted'?
so it won't be so sensitive. :dontknow:

One could certainly reduce the steering angle feedback to the ECU. This would trick the ECU into thinking the wheel is turned less than it actually is and delay VSS engagement.

This may be the only other viable solution, besides overriding the rear wheel sensor signal with the front wheel sensor signal.

 

[RandyL]

Just found this old thread after searching around and wondering if anyone ever came up with a way to reduce or temporarily disable VSS. I'm with lamarguy, would love to have it switchable, or at least a seriously reduced setting.

 

[RandyL]

You can whip endless donuts and not land on your head. Taking off you just tail whip and in the rain you can drift curves. ABS and TCS still work also.

Justin, how do you know this? You must've found a way to disable VSS, please do tell.

 

[Dan_Ashley]

Change your techniques

All MSF riding schools teach that the best way to brake, turn and accelerate is the following:
Try to never brake after initiating a turn, turn, maintain speed with slight throttle through the turn then accelerate when the bike is straight again. They call this maintaining your line. They also teach if you must brake in a turn to straighten the bike first. Clearly these are techniques for the novice rider, but they are well founded in the physics and geometry of motorcycles.

Perhaps it would help your Spyder riding if you practiced some of these in an empty parking lot.

 

[RandyL]

All MSF riding schools teach that the best way to brake, turn and accelerate is the following:
Try to never brake after initiating a turn, turn, maintain speed with slight throttle through the turn then accelerate when the bike is straight again. They call this maintaining your line. They also teach if you must brake in a turn to straighten the bike first. Clearly these are techniques for the novice rider, but they are well founded in the physics and geometry of motorcycles.
Perhaps it would help your Spyder riding if you practiced some of these in an empty parking lot.

Thanks Dan, but what I'm after is a bit less restriction so I can feel more of the vehicle dynamics while still remaining safe. Based on comments in the forum I can see I'm not alone. Also, BRP must be getting the same feedback or they wouldn't have made the following change for 2014...

"NEW Sport-tuned VSS calibration for faster cornering and maximum agility (RS-S ONLY)"

Glad they seem to be listening. One last data point, check out the latest generation electronic controls on the new and well-reviewed BMW R1200GS... five different riding modes where ABS, TCS, and yaw control settings are all changed to allow the rider to both adapt to different circumstances but also preferences based on how much protection they want.

 

[Dan_Ashley]

Good point.

 

[billrob71]

Thanks Dan, but what I'm after is a bit less restriction so I can feel more of the vehicle dynamics while still remaining safe. Based on comments in the forum I can see I'm not alone. Also, BRP must be getting the same feedback or they wouldn't have made the following change for 2014...

"NEW Sport-tuned VSS calibration for faster cornering and maximum agility (RS-S ONLY)"

Glad they seem to be listening. One last data point, check out the latest generation electronic controls on the new and well-reviewed BMW R1200GS... five different riding modes where ABS, TCS, and yaw control settings are all changed to allow the rider to both adapt to different circumstances but also preferences based on how much protection they want.

I agree with ya 100% this is my sole complaint with my bike. I like to ride it more aggressive most of the time. Accelerating out of the apex on a sweeping turn, little harder on the throttle and not mattering how you lean nanny gets mad and shuts ya down, which Im trying to get used to but been couple times thats it's kicked in and feels like im going over the bars or off the side. I'm hoping the calibration is something that can be retro programed to the older bikes, I don't wanna make a gamble on a 2014 $1000 VSS module.