What's causing this Wobble while braking?

[javajaws]

Our 2023 RTL only has a few hundred miles on it and I'm still getting used to the whole 3-wheel thing. But while braking quick from say 30 mph or so there is a mild but noticeable wobble/shimmy while coming to a stop (straight line braking). Is this the Spyder equivalent of bump steer while braking? Or is it caused by rapid downshifting? Will suspension/tire fixes resolve this? Alignment? Just curious to see if this is normal and/or what a potential fix might be. I did just put a BR Ultra sway bar on but haven't had a chance yet to do brake testing (raining). Also have some new shocks and tires on the immediate roadmap.

 

[Bartender]

I had a 2019 RTL for 30,000 miles and now a 2022 Sea to Sky for 5000 miles and have never experienced what you are describing. I would check the front lug nuts and torque them to spec and if that is not the problem get it back to the dealer asap. A properly aligned Spyder with evenly inflated tires should not be unstable whatsoever. I've ever understood what "bumpsteer" actually is. I know with conventional trikes(two wheels in back) I have heard riders talk about needing to bump steer to get through the corners, but have never heard it referred to a Spyder.

 

[javajaws]

I had a 2019 RTL for 30,000 miles and now a 2022 Sea to Sky for 5000 miles and have never experienced what you are describing. I would check the front lug nuts and torque them to spec and if that is not the problem get it back to the dealer asap. A properly aligned Spyder with evenly inflated tires should not be unstable whatsoever. I've ever understood what "bumpsteer" actually is. I know with conventional trikes(two wheels in back) I have heard riders talk about needing to bump steer to get through the corners, but have never heard it referred to a Spyder.

My understanding (somebody correct me if I'm wrong): When weight shifts forward while braking the front end dives (because of shocks/springs being too soft?). This can cause toe to change. If this happens asymmetrically (off camber, or if misaligned?) it could result in "bump steer" causing you to go left or right. However in my case...its more like a slight wobble/shimmy left AND right. Not really too bad, but noticeable. And only while rapidly stopping...not a normal slow application of the brakes stop. But not "emergency stopping" either (haven't really had to do one of those yet!).

As for taking it to a dealer...I have zero confidence in our local dealers to address this and/or not have to wait for several weeks while they look at it (just the reality of dealers in my area). After I get my new shocks in I'll probably be taking it in for an alignment as well at that point, maybe those two things will help.

I'll definitely check nut torque and tire pressure, thx.

 

[BajaRon]

Check the lug nut torque, as already mentioned. Check tire pressures (I recommend 18-20 psi) in the front. Check for bad tie rod ends or bent tie rods. Worn A-Arm bushings will also give you this effect. But with such a new machine, I doubt you have hardware issues unless you've hit something. Last in line would be rotor warpage.

If you are still under warranty, I'd take it to the dealer and hope they put the effort out to find the problem and fix it for free. If you need a rotor, I highly recommend going to the EBC product. Much improved over the OEM rotor. You'd have to get 2 because the EBC rotors stop better and you don't want uneven braking on the front. The good news is that if you have to pay for the rotor, 2 EBC rotors are about the same as 1 BRP rotor.

In any case. I would get it looked at soon. Brake wobble is not a good thing.

 

[BLUEKNIGHT911]

:agree: with #2 & #4, also you have Kenda OEM tires..... Which have the worst record for Defective tires I have ever heard of ..... Why you only notice it when Braking hard I can't address, I think this is odd. .... If you know someone with 15" Spyder wheels and AUTO tires, maybe they would let try those ..... also Spyders feel way different than most anything you drive .... Good luck

 

[javajaws]

So I managed to get out during lunch for some testing. Note that 1) I said I'm still new to 3-wheels, and 2) I had just put an Ultra bar on it (yesterday). I only was able to do a short test ride around the block yesterday.

So a few observations I made:

1) It was less prone to doing the wobble now than before the sway bar install. And when it did happen it wasn't as pronounced - it settled down much faster.

2) I was purposely being more conscious of what I was doing while stopping...and now I think I'm partly to blame (surprise!). I just don't think I'm 100% used to the oversteer these things have and I notice when it occurs its usually initiated by something I'm doing - not applying equal pressure on both sides of the bar, or while manually downshifting right before stopping (which surprise...involves putting pressure on one side of the bar only). If I stop without hands on the bars at all and let it downshift automatically I couldn't reproduce the wobble. Sometimes it wouldn't stop 100% straight but that was on off camber roads. And those times I could induce it my hands were on the bars and I could correlate it to me doing something not equally applied to both sides. So I really guess this is mostly me still getting used to the handling of these machines and how responsive they are to small inputs on steering. I can't prove that some instances I had experienced previously were induced by bump steer while coming to a stop - but if true that's not really the fault of the machine really (other than having a soft suspension). I think in those cases the new sway bar will help and obviously new shocks/springs and tires would as well.

So please, nobody read much into my thread here (not knocking my Spyder which I love!) and thanks for the suggestions.

 

[SLICE]

Remember you have to keep that light touch on the bars even under hard braking.

when I first got my 2022 RT-L I was all over the road and even went in other lanes when I was braking hard.

When you brake hard your mind tells you to grip hard.

We/you all of us have to keep that light touch on the bars

 

[EdMat]

It may also be that you need more time to get the lines of communication going between you and the Spyder. During hard braking you would tend to put extra pressure on the back of the bars. Any unevenness would start the condition you describe and your subconscious reaction would further it along. At some point that subconscious reaction will wane and you will be left wondering what the big deal was.

I think you should still check it mechanically to be safe.

Happy miles and smiles

 

[FrogmanDave]

You may find out your tires are not balanced correctly. The tires on my Spyder are out of round and will not balance. I'll run them until they need replaced, but the quality does seem to be somewhat lacking. You may be feeling some of that.

 

[fredgal]

about the OEM tires.. i noticed last week while using cruise control, using no hands, bike goes straight as can be, but has 1/2 in handlebar back and forth shake, 2500 miles on my 2020 F3L.. just received 2 quadtrac tires from tire rack, 165/60/15's... they are going on next monday am. kenda tires are junk...:spyder2:

 

[bigbadbrucie]

It took me at least 1,000 miles before I was “comfortable” on the Spyder. Give it time, and keep on and practice, practice, practice. As for the tires.....new tires are not that expensive, but your well being is... I would NOT fool around. Replace!
Just my humble opinion....do what you think is best!

 

[javajaws]

I do my homework and thanks to all you guys...I actually already have a new set of 3 Vredestein's in the garage. I might go ahead and put them on this week...I'm just trying to do the "change one thing at a time only" and working my way through the upgrades...

 

[JKMSPYDER]

I vote for a warped rotor problem. I had a bad shimmy on the right front wheel when doing hard braking. I took the rotor off and put it on a glass table. I was able to insert a sheet of paper under some parts of it. I rode to BajaRon’s shop and they put a measuring device on it and, sure enough, it was warped. Two new EBC rotors fixed the problem.

 

[Bunson]

The spyder is a unique veichle. As I read through this thread I was thinking to myself: get your hands off the bars. I thought I had a problem because the bike seemed to pull mainly to the left under hard braking. I was about to tear into things and thought of taking my hands completely off the bars before hitting the brakes and sure enough the bike stopped straight. Light grip, light grip and even lighter grip. It's hard to do when braking hard. Most of us riders are older guys you only dream of having strong core muscles.

 

[fredgal]

The spyder is a unique veichle. As I read through this thread I was thinking to myself: get your hands off the bars. I thought I had a problem because the bike seemed to pull mainly to the left under hard braking. I was about to tear into things and thought of taking my hands completely off the bars before hitting the brakes and sure enough the bike stopped straight. Light grip, light grip and even lighter grip. It's hard to do when braking hard. Most of us riders are older guys you only dream of having strong core muscles.

yep old guys, turned 65 sunday.....:yes:

 

[Mikey]

My friend last year came to me and said, Mike I have a wobble in my bike. So I got on the old girl and down the road I went, well I got out on the main road and shifted up threw the gears, right up to 55-60, then I let off the gas and OMG, That thing went into this wobble thing that made my butt tighten up!!! Well, I played with it all the way back to the house, pulled into the dooryard and right into the shop! I went up and down the thing and asked when it started doing the shake wobble thing, he said it always did it a little but really started thr=e shake when a set of tires were put on the front! I spun and shook everything, when I was done I told him, take this thing back and have them rebalance the tires, and if they won't do it pull it into a tire shop and have them do the front tires for you. Next day he showed up and said thank you, thank you, what a difference it made, never drove so well ever!!! So, tire pressure, lug nuts, balance, rotors, and depending on how hard your pushing and the surface of the road the abs could be making it do a little dance also! Good luck!! Get some miles under your belt relax your grip and be one with your ride!!:cheers:

 

[BLUEKNIGHT911]

about the OEM tires.. i noticed last week while using cruise control, using no hands, bike goes straight as can be, but has 1/2 in handlebar back and forth shake, 2500 miles on my 2020 F3L.. just received 2 quadtrac tires from tire rack, 165/60/15's... they are going on next monday am. kenda tires are junk...:spyder2:

I think all Spyder,s have some slack 1/4 to 1/2 inch ( at the handlebars ) in the steering mechanism. If you completely remove your hands from the bars, ( I have done this ) if the alignment is good the wheels/tires will track straight but the bars will shake a very small amount ..... Mike :thumbup:

 

[BLUEKNIGHT911]

I vote for a warped rotor problem. I had a bad shimmy on the right front wheel when doing hard braking. I took the rotor off and put it on a glass table. I was able to insert a sheet of paper under some parts of it. I rode to BajaRon’s shop and they put a measuring device on it and, sure enough, it was warped. Two new EBC rotors fixed the problem.

I think the likelihood that a new 2023 would have Warped Rotors is very slim ..... JMHO ... Mike :thumbup:

 

[BajaRon]

Biggest problem with Kendas is, they aren't round. And, just like with stupid, it can't be fixed.

 

[Knizar]

Biggest problem with Kendas is, they aren't round. And, just like with stupid, it can't be fixed.

:agree: A mouthful of Truth! Stupid can sometimes be improved, but oblong tires will never B round! :thumbup:..Bill