Front end wobble

[aka1004]

2015 RS with vredestein tires at 20lb and fox 1.5 shock with adjustable rebound.
It wobbles a bit at hard braking and hard acceleration. Well, wobble at hard braking and loose at hard acceleration would be more accurate.
Laser alignment was done and rotor seemed ok when I checked while replacing the brake pads.
Do you think less or more preload might help? I only played with rebound so far.
Thank you in advance.

[BLUEKNIGHT911]

2015 RS with vredestein tires at 20lb and fox 1.5 shock with adjustable rebound.
It wobbles a bit at hard braking and hard acceleration. Well, wobble at hard braking and loose at hard acceleration would be more accurate.
Laser alignment was done and rotor seemed ok when I checked while replacing the brake pads.
Do you think less or more preload might help? I only played with rebound so far.
Thank you in advance.

trying to narrow down the possibilities ..... When the Spyder wasn't wobbling .... what did you do to Spyder and then started to notice the wobble .... Vredestein's are a high quality tire .... un-like Kenda's, ..... Mike

[bikerchris1270]

2015 RS with vredestein tires at 20lb and fox 1.5 shock with adjustable rebound.
It wobbles a bit at hard braking and hard acceleration. Well, wobble at hard braking and loose at hard acceleration would be more accurate.

Laser alignment was done and rotor seemed ok when I checked while replacing the brake pads.
Do you think less or more preload might help? I only played with rebound so far.
.....

Hmmmm.......
1.) Check for loose/ worn suspension components. Unweight front suspension, check.
2.) Check for lateral runout of wheels(bent rim)
3.) Warped brake rotors?
4.)For giggles, swap front tires side to side.
5.) When they did alignment, was the Torque sensor and the SAS sensor reset?

[PMK]

Under braking, the front suspension compresses, the front wheels toe out, which induces instability. If there are no worn ball joints, suspension pivots tie rod ends, or items others mentioned, you likely need more toe in.

Since you mention issues also under acceleration, you might consider ensuring the rear axle is tight and the swingarm pivot is tight.s

[BajaRon]

I would add, correctly torqueing the front wheels in a multiple step process. Maybe a longshot. But eliminate the easy stuff first.

[aka1004]

I should have given the whole story.
I bought the 3 year old RS with 700 miles on it and it was darting under braking but without consistency. Sometimes it would dart right other times left and sometimes it didn’t dart at all. A lot of that was cured after replacing the fronts with vredestein.

Now what I noticed after brake pads were replaced and was sitting the new pads was it didn’t dart but little instability under hard braking.
Looseness came when I was making a high speed pass. When I went full throttle, front end got loose enough to force me to ease the throttle. I could feel the front wheels loosing traction. I just installed power commander and took out the resonator on factory air box so should have gained a little more but I don’t know if that was to make that much of difference.

Rear is another story. I have the altimax? With 22 lb but this was not a good tire.
It might have been good as a long lasting tire on RT for touring but not when you wanna get to speed limit ASAP. it looses traction real easy.

[K80Shooter]

It could be that the front calipers are sticking a little and warped the disc/rotor from heat buildup. Just a guess.

[aka1004]

Suspension has been the most challenging thing on spyder.
I don’t have much experience on other mechanical work(never changed oil in any vehicle before buying the first spyder 13 years ago) neither but I’ve been able to get enough info especially from spyderlovers and watching YouTube to do a lot of work on spyder myself but suspension is very tricky.
Elka, after taking my weight, 1or 2 rider and my riding style, sending a rear shock that’s not close to where it should be didn’t help neither. It was bottoming real bad and rebound was way off too.
Internet came to rescue again and I’ve been learning.
I dialed in the rebound on front to the point where it feels like it’s handling/turn much better than before but I don’t know if that may have created a little wobble when braking.??? You would think if front end of spyder is more solid when turning, it should feel more solid when braking.

[BLUEKNIGHT911]

Suspension has been the most challenging thing on spyder.
I don’t have much experience on other mechanical work(never changed oil in any vehicle before buying the first spyder 13 years ago) neither but I’ve been able to get enough info especially from spyderlovers and watching YouTube to do a lot of work on spyder myself but suspension is very tricky.
Elka, after taking my weight, 1or 2 rider and my riding style, sending a rear shock that’s not close to where it should be didn’t help neither. It was bottoming real bad and rebound was way off too.
Internet came to rescue again and I’ve been learning.
I dialed in the rebound on front to the point where it feels like it’s handling/turn much better than before but I don’t know if that may have created a little wobble when braking.??? You would think if front end of spyder is more solid when turning, it should feel more solid when braking.

" Pedal commander ", adds NO power it just makes the throttle like a " hair trigger " .... 22 lbs in an Altimax RT is 4 lbs to much..... Can you shut the Commander OFF ???? .... if so try that .... imho the Stock shocks work fine ... especially if you have Ron's Swaybar ..... good luck .... Mike

[2dogs]

As Ron said, do the easy stuff first. While torquing the front lug nuts feel for any slack in the wheels, lose bearings and etc. and watch the handlebars at the same time. Look for any excessive movement or lack of movement. Does everything seem tight at low speed? Because of full acceleration, the front will tend to rise a bit as mentioned above. Drop the tire pressure to 16/17 and get a bit more rubber on the pavement. Also, a death grip on the handlebars will tend to cause wabble and darting sensation. If all the easy stuff checks out ok you may want to revisit the laser alignment.

[aka1004]

Thank you all for suggestions and I installed POWER commander, not pedal.
I do have Ron’s swaybar and fox podium 1.5 with rebound adjustment and elka rear with rebound adjustment.
I will try dropping the psi on all 3 and add little more preload on front shock.

[EdMat]

I will try dropping the psi on all 3 and add little more preload on front shock.

Try one thing at a time.

[Bottomline2000]

Thank you all for suggestions and I installed POWER commander, not pedal.
I do have Ron’s swaybar and fox podium 1.5 with rebound adjustment and elka rear with rebound adjustment.
I will try dropping the psi on all 3 and add little more preload on front shock.

set your front preload so that you are back to factory ride height. I had a similar issue setting up my M2 shocks and things didn't seem to work right until I got the ride height back to the correct level. Then you can adjust the shock itself. this may explain the change in toe in/out from acceleration, deceleration and twitchy steering..

[Wmoater]

Go for a short ride (slow) turn music off and just go 30 and let it coast. Do you hear scraping on the front brakes? Now apply brakes slowly does it feel like the brakes are surging? Now go 50 apply brakes hard is that the wobble when you apply hard high speed? If it’s surging at low speed and hear scraping I saw it’s the rotors. One other thing since you have adjustable shocks, are they the same setting? Back both all the way off and adjust the same either with air or twist. You need to make one adjustment at time. So you’ve been given 8 so far above. Do one at a time and dial it in.

[2dogs]

Try one thing at a time.

Very good advice EdMat. I know exactly what you mean. I'm 100% guilty of doing more than one thing at a time trying to resolve a problem issue.

[aka1004]

Will 68mm spanner fit front fox 1.5 podium?

[aka1004]

I lifted spyder and when I spun the front wheels, the noise it makes as rotor runs through the brake were not consistent. It was like some part of rotor was contacting the pads more than other , kind of alternating wave of sound??? But just slightly.
Since I haven’t done this before I’m not sure if that’s normal or sign of warped rotor.

[2dogs]

I lifted spyder and when I spun the front wheels, the noise it makes as rotor runs through the brake were not consistent. It was like some part of rotor was contacting the pads more than other , kind of alternating wave of sound??? But just slightly.
Since I haven’t done this before I’m not sure if that’s normal or sign of warped rotor.

Possible rotor warp. Watch it close as you turn the wheel. Not an uncommon issue. Take off the wheel and check the pads for uneven wear.

[Ex-Rocket]

That sounds like a warped rotor. If you have the wheel off the ground and spin the tire the sound should not get loader and then softer as the tire spins. The sound should be consistent.

[aka1004]

Brake pads are brand new, may be 100 miles on it.
I understand that warped rotor would cause wobble under braking but it doesn’t cause front end to loose traction under hard acceleration, does it? I’m thinking it’s two separate issues.

[Wmoater]

Warped rotors will wobble front end really bad if brakes are applied forcefully. That’s why I said do at low and high speed. That would be the wobble at high speed braking. Pre load uneven or to tight of shocks would cause it on acceleration. I’d first get air correct in tires and check and test. Next check the lugs, remove and retighten to 77 and test. Next loosen the shocks to Oem setting and test. Other words loosen so no pressure. Test. Add a pound of air in shocks or a twist depending on which setup and make sure spyder is level sitting on it. If the front is to high or loaded there’s no down force taking off. My opinion I like the front a touch lower. I’ve set many snowmobiles up with shocks and a correctly dialed in shocks make a huge difference. Incorrect setting will cause lift at the acceleration. If the fronts are to stiff and the backs soft it’s going to be sloppy. Both the fronts and backs must mate while sitting on it. One extreme on one end will cause lift. A stiffer rear and touch softer front is best as long as it level sitting on it. Baja Ron knows the measurements. Follow his recommendations on the shock setup. It’s best to start everything soft and adjust accordingly. Rear then fronts. Test after each shock adjustment. Slow and steady.

[2dogs]

My Jeep Grand Cherokees for several years had front rotor warpage problems. Bought Summit premium racing rotors and still had the same problem. A Summit tech advisor gave me a driving formula to heat up my Jeep's rotors and then how to cool them down. The process was to supposed remove the warp out of the rotor. I'll be dammed if it didn't work. Don't know if that process would work on a spyder or not? Basically, heat them up and get them real hot, then let them cool without using them.

[Peter Aawen]

Just to add another 'possible issue' into the mix, one of our 'more mechanically savvy' members here Pinkrosepetal (here as in, 'on the Forum', but actually a UK based member ) discovered that at least some front discs aren't squarely mounted on the hub/spindle, which can cause a 'wobble' as well as disc/pad wear issues & may potentially even cause 'wobble under acceleration'!

Might be worth your while to do a search on pinkrosepetal's posts to see if that particular issue sounds anything like your concerns aka1004. Over to you!

[aka1004]

Since rotors are kinda floating on three bolts , how do you make sure it’s properly seated?

Just to add another 'possible issue' into the mix, one of our 'more mechanically savvy' members here Pinkrosepetal (here as in, 'on the Forum', but actually a UK based member ) discovered that at least some front discs aren't squarely mounted on the hub/spindle, which can cause a 'wobble' as well as disc/pad wear issues & may potentially even cause 'wobble under acceleration'!

Might be worth your while to do a search on pinkrosepetal's posts to see if that particular issue sounds anything like your concerns aka1004. Over to you!

[2dogs]

Another way I've been told to check rotor warpage is to remove the rotor and place it on a piece of glass and see if it rocks back and forth. Then turn it over and do the same thing again. If it does then it warped. Make sure it's a thick flat piece of glass. You can even use a straight edge, but it is easier with the glass.