Wheel wobble on both Rover and Wagon with no hands

[GOWYO]

Back in July I bought both a Rover and a Wagon for my wife and I to use. Our first ebikes. There is a fairly long story about Rad's initial denial of a problem followed by a partial resolution that is not yet complete. But the purpose of this post is to get anybody's opinions about this problem. If you ride with no hands, the Rover front wheel begins to wobble wildly at around 12mph. On the Wagon it happens more like 16-17mph. I had both bikes shipped to a local shop that sells exclusively ebikes of many kinds AND uses RAD bikes for his rental fleet. He assembled my bike, as he has dozens of Rad and other brands of ebikes. I cannot replicate this wobble on his Rad rental bikes. I take my hands off the bars and pedal along just fine. He has switched wheels, checked forks and spokes, but no joy. I'll tell you later what Rad has agreed to, but suffice it to say that I'm not really satisfied and want, for now, only technical opinions on whether any ebike should be able to be ridden with no hands and not encounter this dangerous wobble.

Here's a video of one of the bikes and how it wobbles:

 

[RangerDave]

Here is an interesting article and video on your situation.

Shimmy or Speed Wobble by Jobst Brandt

Article by Jobst Brandt about front-end oscillation of bicycles

www.sheldonbrown.com

 

[GOWYO]

Some sort of 'flex' going on somewhere with your ebike's frames. Does any wobble occur at all when you have your hands on the handlebars, even if lightly gripping them ?

On the Rover, it has a thin downtube and the headset height off the front wheel, coupled with the type of stem they are using could magnify any issue with frame flex. Wheel wobble issues date back to 2016 on the Rover. So you aren't the first person to experience this.

On the Rad Wagon, I've had others bring theirs in to my shop to see if it can be resolved. It's a long wheel base, again coupled with a thinner bottom down tube, and a very odd headset position, and spacing between two downtubes.

So did they just tell you not to ride no handed ?

Also, how tall are you and your wife, and have others tried your ebikes and experienced the same wobble issues ?

I'm 6'0", My wife is 5'7". The owner of the bike shop rode and confirmed the wobble on the Rover. There is some wobble in the handle bars while gripping, but really mostly when I'm "standing" to accelerate. Rad is replacing my Rover but won't do anything about the Wagon... too much to ask, I guess. And, you're right, the customer service rep said riding with no hands is dangerous. I *want* to point out that she was obivously never a 7 year-old boy, because in my experience you can't get through second grade without attaining that skill.. "Look Ma! No Hands!" I mean, it's a completely understood cultural reference. I think what gets me is that I have ridden the exact model of bike with no hands and not had it wobble... and it's still under warranty, so what's their problem? I mean, other than being a direct-to-consumer company with some quality control issues. I accept that you get what you pay for, to some extent.

 

[GOWYO]

Here is an interesting article and video on your situation.

Shimmy or Speed Wobble by Jobst Brandt

Article by Jobst Brandt about front-end oscillation of bicycles

www.sheldonbrown.com

Thanks. Food for thought...

 

[mrgold35]

I've had my two Radrovers since 2016 with around +7000 miles between them. Changed out the tires from OEM to Vee8 26X4 120 tpi and keep my psi 20-23. Added the Sunlite 0-60 handle bar adjuster for a more comfy ride at 6'3". I mostly work commute on the rovers with some downhill speeds of 24-26 mph if I push her. I also have the wobble if I let go; but, don't feel (or don't notice) the wobble with one/two hands on the handle bars. I haven't check to see if the the wife's Radcity step-thru does the same?

 

[christob]

I'll only chime in that my bike (not a Rad) had a noticeable front wheel "wobble" if I attempted hands-free at reasonable speeds (say, under 13mph). I don't routinely ride hands-free, but now and again on a long straight flat, its nice to sit upright a few seconds, hands-off.
Ultimately in my case, it appears it was a symptom of several extremely loose rear wheel spokes. I had the rear wheel go through a proper spoke exam, re-tightening & re-true, done by my LBS's master wheel builder, and the wobble completely disappeared. Not saying that will solve your issue, but based on my experience it could perhaps something to explore.

 

[Tars Tarkas]

I have a 2018 Rover and don't have any wobble that I've noticed. I think I've heard that that kind of wobble can be a symptom of too much weight on the back, or, I guess, too little on the front. It might be worth experimenting with moving some weight around.

TT

 

[mrgold35]

I have a 2018 Rover and don't have any wobble that I've noticed. I think I've heard that that kind of wobble can be a symptom of too much weight on the back, or, I guess, too little on the front. It might be worth experimenting with moving some weight around.

TT

I'm +300 lbs with full winter gear+commuter backpack+Topeak rack bag with spare parts/tools. I would probably flip over backwards if I sit up straight on my rover.

 

[applen]

I'm just under 6'2" and have a significant wobble on my Radwagon at pretty much every speed (amplitude increases with speed). Even one-handed riding I can feel it starting. I really have to have the front bars weighted to stabilize the system - which isn't that easy given the upright riding position.

Since the rear drop-outs are ~horizontal I did notice that it wasn't perfectly aligned with the front: but straightening it didn't fix it, just changed it slightly. Next I plan to true the rear wheel so that at least spoke tension is even... but honestly I think it has to do with my center of mass being so high in the middle/above the long/heavy frame: the whole thing just seems to pivot->oscillate around my (fully extended) seat post. I should note that I have the large front basket and usually have some weight in there (a bike lock at minimum) - I took of the basket (but not the front rack) to see if that helped and it did but didn't remove the wobble completely. Moving my yepp kids seat to the front position helps a bit too but still doesn't make the wobble go away.

Honestly I can live with it because this bike is so good for what I need... but as an engineer, sometimes bike racer, and often-mechanical-perfectionist: it does drive me a tad nuts. I'll reply to this thread if I make any progress.

 

[AHicks]

Applen, your note cause me to want to share that I've also been described as a mechanical perfectionist (anal by some) but I'm OK with this wobble as well. You see, I have no interest in even testing my bike to see what it does when I let go with both hands!

I would add that while riding, I don't feel any monkey motion that might draw attention to any problem that might be traced to a/causing a handling issue. 2018 Rad City. FWIW, -Al