[xsever]

On my way to get the motor cleaned, the problem was not there. Steering was smooth as ever.

I cleaned the brushes, the commutator, and the rotor from all the dust coming from the brushes. I also cleaned the gaps in the commutator. Everything looked brand new after all the cleaning. The brushes still had plenty of life in them so I left them.

I did not want to risk pulling out the entire motor assembly since I know there are 2 wires connected to the DPS board inside.

After the cleaning, the steering continued to be smooth and I am not sure if it's placebo but it felt smoother than before. I also fixed a small toe in I had in the front right tire. It needed two twists of the tie rod ends to get a perfect result.

Hopefully this will be the end of it. Will keep you guys posted.

 

[Tozguy]

It needed two twists of the tie rod ends to get a perfect result

Two full turns of the tie rod seems like a big adjustment. Do you think that the front wheel misalignment could have been contributing to the steering stutter?

 

[xsever]

Two full turns of the tie rod seems like a big adjustment. Do you think that the front wheel misalignment could have been contributing to the steering stutter?

It's possible but the tie rod ends were replaced 2 years ago when I bought the ATV and the toe in was there since then I guess. I need to ride the ATV more to make sure the problem is gone and to see if the steering feeling is better now with the toe in removed.

 

[Tozguy]

This page from a shop manual is what prompted my question about a potential relationship between tie rod adjustment and steering problems:

 

[xsever]

Went for a ride yesterday in chilly weather and did some snow riding and rock crawling and DPS worked phenomenally!

At high speed on pavement where DPS assist is weaker, I did not notice any before/after difference but at slow speed where DPS assist is stronger, I could tell steering was easier and smoother than before.

One thing I noticed is that the handlebars need to be turned every so little to the right for the bike to drive straight. Shall I get BUDS connected and zero-in/reset the DPS unit to make sure straight handlebars don't result in the DPS unit detecting an input torque and hence producing an output torque at the motor?

 

[Freewill]

Shall I get BUDS connected and zero-in/reset the DPS unit to make sure straight handlebars don't result in the DPS unit detecting an input torque and hence producing an output torque at the motor?

Might be a good idea so it is not always trying to assist a turn when you are going straight.

 

[Tozguy]

I also fixed a small toe in I had in the front right tire. It needed two twists of the tie rod ends to get a perfect result.

the handlebars need to be turned every so little to the right for the bike to drive straight.

Could this steering bias be corrected by revisiting the toe in adjustment that was made? Was the tie rod adjustment all done on the one side?

 

[xsever]

Could this steering bias be corrected by revisiting the toe in adjustment that was made? Was the tie rod adjustment all done on the one side?

The toe adjustment was made using a wire sprung from the rear tire of each side.

The front left tire was in perfect alignment with the rear left tire and only the front right tire needed adjustment to become in perfect alignment with the rear right tire.

 

[Tozguy]

On my 450 the rear tires are wider than the front. Using the string method shown in the manual it was difficult to get a good reading on alignment. I increased toe in slightly by adjusting on each side equally to keep the handlebars in the same position as well as not upset the DPS. This might not relate to your situation however.

 

[xsever]

On my 450 the rear tires are wider than the front. Using the string method shown in the manual it was difficult to get a good reading on alignment. I increased toe in slightly by adjusting on each side equally to keep the handlebars in the same position as well as not upset the DPS. This might not relate to your situation however.

Thanks for the valuable feedback. I should've mentioned that I have spacers on all 4 corners. My front tires are 9 wide and rear ones are 12 wide.

I'm not an alignment expert to know if what I did is the correct thing to do or whether there's something else to be done as well.

 

[Tozguy]

One thing I noticed is that the handlebars need to be turned every so little to the right for the bike to drive straight.

This means that the right wheel you adjusted is pointing too far left. If you are satisfied that the front wheels are parallel, I humbly suggest that you adjust the right wheel for more toe out by 1/2 a turn and the left wheel for more toe in by a 1/2 turn. And see what gives.

My approach to checking front wheel alignment is to hold a straightedge across the front tire at axle level and slide it up to the rear tire. The handlebars have to be dead square. The straight edge has to butt at the same point on the rear tire on both sides.
A length of gyproc molding can be used as a straight edge in a pinch.
I find that it is worthwhile to to measure the actual front and rear track accurately so that you know how far in on the rear tire the straight edge has to be when the front wheel is aligned.

 

[Freewill]

When I align tag axles on semi trucks and trailers or the steer axle, I jack up the tire so it is off the ground, spin the tire and use a marker or paint pen, or spray paint and a screwdriver on a jackstand to make a perfect line around the center of the tread. This way if a tire is slightly out of round, or the rim slightly bent, the line will be true with the spindle. Do both sides. Then with independent front suspension, set the steer axle tires on the floor with the natural weight of the machine on them. Then use a measuring tape with assistance from someone else and measure from line to line on both front and back side of the tires setting about 1/32 or 1/16 toe in. That is how I have done alignments for many years. Always works great.

 

[TheSponge]

Do what the Jeep guys do. Square tubing, works great. The string method isn’t that accurate.

How to align your Jeep Wrangler TJ

Here's how to check and adjust your own toe-in that also includes how to center the steering wheel. Using the info at http://www.4x4xplor.com/alignment.html, set your toe-in so the fronts of the tires are 1/16" to 1/8" closer together in front than in the rear. This is done by loosening the...

wranglertjforum.com

 

[xsever]

For anyone interested in learning what's inside the DPS module, check this thread out: DPS..... What's in the box.

If you go to the end of the thread, you will find out that heat coming from the radiator is the #1 heat source that can overheat the DPS module. The solution is to block off the warm air path after the radiator and before the DPS.

I've had this mod implemented since last summer but I guess I never discussed it here yet.

Pretty interesting stuff.

 

[xsever]

I finally had the time to do a proper alignment of my ATV yesterday using the technique used in this video and my digital caliper to very precisely measure and adjust toe:

I then test drove it and it rode straight as an arrow but I still felt that turning left was a bit more difficult than turning right so I called the local BUDS guy and he showed up today.

We centered the handlebars perfectly and then reset the DPS and the ATV now steers flawlessly. He did point out that the 2 in spacers make the steering response much more difficult compared to if they weren't there but I am happy with it now.

We also went through the entire ATV using BUDS and everything was fine. The only old faults that popped up were the ones related to DPS and we erased them.

We also checked for ECU and DPS updates but there weren't any. He stayed over for like 2 hours maybe and charged me $40.

Problem fully solved and I hope this thread will help members diagnose and fix their DPS when it malfunctions.

 

[Msprygada]

Howdy gents,

Went for a ride today and halfway through I started feeling the handlebars stuttering so I stopped and indeed the handlebars/steering would stutter at a standstill as I barely tried to steer. As if the DPS was twitching.

I turned the ATV off and removed the front inner fenders to see if the DPS motor was too hot but no. It was warm but nothing alarming.

All connections were strong.

I continued on and could feel the twitching getting worse until I started feeling that the DPS was fighting my inputs.

A bit later, I got the Check DPS warning, the check engine light came on and I lost power steering.

If I turn off the ATV and turn it back on, the check engine light and error message disappear until I drive it a bit and I wrestle with the DPS a bit before they come back on and I lose power steering again.

I checked the battery voltage and it's 12.7V while OFF and 14 while ON. I checked all the connections and they're ok.

I never ever had a warning for the DPS motor being too hot or any of that sort. This is my first problem with DPS.

Pulled the following codes using the cluster (don't have BUDS) :
U0426 - Invalid data received – immobilizer (most likely an old code and unrelated)
P0636 - Power Steering Control Circuit Lo

From what I've read, it's looking like the DPS unit at $840 😭 unless aftermarket options exist.

What do you suggest I do next?

Thanks.

Where did you find a DPS unit for $850? Maybe yours is different than mine but the going rate is almost $1700. I did eventually find one for a little over $1200 (partzilla).

 

[xsever]

Where did you find a DPS unit for $850? Maybe yours is different than mine but the going rate is almost $1700. I did eventually find one for a little over $1200 (partzilla).

Where did you find a DPS unit for $850? Maybe yours is different than mine but the going rate is almost $1700. I did eventually find one for a little over $1200 (partzilla).

My ATV is a 2016 model so it uses the older style DPS unit which I guess is cheaper. I was seeing that price on Partzilla.

 

[Jack796]

When i do aligment. I always strap handlebar to center of course. So it will not move when adjustment is made.. in my use i have toe-out about 2-3mm. If aligment is not right dps unit will "try" center it all time = getting Hot and shut down.. eventually it will be broke..

 

[xsever]

If aligment is not right dps unit will "try" center it all time = getting Hot and shut down.. eventually it will be broke..

Yes exactly and that's why I had my DPS reset and aligned after I did an alignment last summer.

 

[Msprygada]

The DSP unit does not try to reset to the center line of the quad, that is what caster in the alignment does. Same with your car. The DPS tries to recenter to the torque sensor which is what detects if pressure is applied to the handlebars that is different than the direction they are currently moving.

I am not sure how I does it but the torque sensor can detect when you are applying pressure to the bars in either direction that is different than the current path of the front wheels and applies some power to help you. That is why is it called a "torque" sensor. When you try to turn your bars, there is torque (twist) applied to the steering shaft. So if you are going straight and you are not trying to turn the bars (no torque applied to the steering shaft running thru the DPS), the DPS unit is basically doing nothing. Same thing if you have your wheel turned 30 degrees to either direction and you are holding your bars in the 30 degree position, then the DPS is not doing anything in this case either.

What the DPS reset does is says to the circuit, currently there is no pressure being currently applied to the handlebars so set this as the new center of the torque sensor. Because if that is off, then you are correct, the DPS is always trying to add pressure to turn the wheels. It has nothing to do with the alignment of the front end components.

Like I just had mine reset because I was hit and the torque sensor was knocked so far out of alignment that the DPS was always trying to turn it left. There was nothing wrong with the alignment, just the torque sensor was jarred. So I had it reset and now it stays pointed in the direction that I point it in.