ST2 Motor "Judder"

[Chuck E. Cheese]

So I got my ST2 last Friday. I have 105 miles on it so far, and until today was thrilled beyond belief with everything about it.

On a ride this afternoon I came to a short, steep hill. I downshifted. I was going about 10 MPH and the bike began vibrating. There was a distinct loss of power as well. I thought (hoped?)I had broken a spoke or bent the brake rotor. I got off the bike and looked it over. Everything seemed in order. When I spun the heels off the ground they didn't make any noise or vibration. I walked it unpowered and it was fine. I pedaled without the motor on. No problem- except for the weight coupled with the low tire pressure. I got off, turned it on and put it in "move" mode. Within 10 feet the vibrations started again. It was definitely the motor. It didn't feel warm, but I accepted my fate. I started the three mile uphill walk back to my office. After a mile or so, I decided to try the "move" mode again in case it had be a heat issue. It did the same thing for a few seconds, then felt as though it actually was pulling it in reverse for a second (could have been no power and gravity), but then suddenly stopped shuddering and seemed fine. I kept it in move mode for a few hundred yards and then thought I'd try riding it once I got to the top of the hill I was on. It rode perfectly the two miles back to the office. I googled "Stromer Motor Vibration" and this video came up:

It looks like the exact issue I have. I bought it from Crazy Lenny's in Madison, WI, and I live in Vermont. The nearest dealer (other than Montreal- and I don't know what issues there might be bringing it across the border) is 3.5 hours away in New Hampshire. Any thoughts or suggestions? Crazy Lenny's said I could ship it back if I couldn't find a fix locally, but that's expensive and time consuming. Thanks for any suggestions. Sorry for the overly-detailed post.

 

[opimax]

I bought from Lenny also, no problem. I also knew If I had issues I would have to go elsewhere, did you figure out "elsewhere" before you bought? if not Call the 800 number at Stromer and ask for help. I cant find it right now. You will pay for labor and Stromer will supply the parts. Probably a new motor which includes the the rim. If you speak with Stromer ask them if they can send it pre-built w/everything already attached. You will pay the shop to transfer any part that is not already on the wheel (rotor, tire, cassette).

You will have to go the nearest authorized shop, they wont send you the wheel (assuming it is the wheel) that is an old video, motors are different now

 

[Chuck E. Cheese]

I bought from Lenny also, no problem. I also knew If I had issues I would have to go elsewhere, did you figure out "elsewhere" before you bought? if not Call the 800 number at Stromer and ask for help. I cant find it right now. You will pay for labor and Stromer will supply the parts. Probably a new motor which includes the the rim. If you speak with Stromer ask them if they can send it pre-built w/everything already attached. You will pay the shop to transfer any part that is not already on the wheel (rotor, tire, cassette).

You will have to go the nearest authorized shop, they wont send you the wheel (assuming it is the wheel) that is an old video, motors are different now

Thanks for the suggestion. I'll call Stromer in the morning. Right now I have work I didn't finish because I was out walking my bike.

 

[Chuck E. Cheese]

I thought Stromer U.S. was on the East Coast. Lucky for me I am and they aren't. Sometimes that time difference is a really good thing. After work I called and spoke with a super helpful rep who thought it might be nothing more than a poorly seated motor control cable. I dropped the rear wheel, reseated the connector and everything seems to be all set. Whew.

 

[Ravi Kempaiah]

I thought Stromer U.S. was on the East Coast. Lucky for me I am and they aren't. Sometimes that time difference is a really good thing. After work I called and spoke with a super helpful rep who thought it might be nothing more than a poorly seated motor control cable. I dropped the rear wheel, reseated the connector and everything seems to be all set. Whew.

That's exactly right! [Hope you spoke to Joel or Mike, very nice folks!]
I was going to tell you the same. I remember an unfortunate during my cross country ride, middle of the night, I had a flat.
It was pitch dark and zillion mosquitoes in the forest area. Somehow I fixed the flat only to hear this noise and jerky ride. It took me an hour but once I seated the cable properly, everything went smooth.

With over 10K miles on the ST2 platform, I have seen my share of problems and sometimes astonished how simple of a fix that can be.
For example, if you know how to feather the brakes such that it only engages regen but not the calipers, you can ride with the same brake pads for over 5000 miles.
I found that using the regen effectively increases the range by 5 miles per full battery charge.

Feel free to contact me if you have any trouble in the future

 

[smitty]

Great story, great ending....and again one can pick up so many tidbits from this forum. Any contact I have had with Stromer has been a pleasure...they want happy riders and try hard to make that happen. Having spent 42 years in Vermont, I have little interest in going to NYC for work on my ST-2. I remain ever hopeful that they will establish a dealership in the central NY area at some point. Crazy Lenny’s the man but Madison, WI is far far away from many of us. There is a lot of beautiful country to ride in Vermont...I hope the bike will continue to treat you well. Between this forum, some calls to Stromer, and my LBS I have managed to keep the bike riding well and past 3K at this point in time. I would settle for a Stromer dealership in Burlington...I bet that you would too. Happy riding and be careful out there on those Vermont roads...

 

[Chuck E. Cheese]

Great story, great ending....and again one can pick up so many tidbits from this forum. Any contact I have had with Stromer has been a pleasure...they want happy riders and try hard to make that happen. Having spent 42 years in Vermont, I have little interest in going to NYC for work on my ST-2. I remain ever hopeful that they will establish a dealership in the central NY area at some point. Crazy Lenny’s the man but Madison, WI is far far away from many of us. There is a lot of beautiful country to ride in Vermont...I hope the bike will continue to treat you well. Between this forum, some calls to Stromer, and my LBS I have managed to keep the bike riding well and past 3K at this point in time. I would settle for a Stromer dealership in Burlington...I bet that you would too. Happy riding and be careful out there on those Vermont roads...

It would have been a great story, but for the sequel. Sequels are never as good as the original, and this case the protagonist loses.

It happened again. The motor began vibrating harshly every time I applied enough torque to engage the motor. Brake regen seems to cause it as well, though to a lesser degree. I repeated the same procedure: removed the rear wheel, unplugged the motor control cable and swore as I balanced a 20 lb wheel on my knee while guiding the rotor back into the brake and aligned the connector back in to place. It’s a PITA, but it went back together fine. But no luck. Same issue.

I’ll call Crazy Lenny’s in the morning and see if they have anything helpful to suggest. If not, I’ll call Stromer on Monday.

There’s a video on YouTube demonstrating step-by-step how to replace a motor controller cable in an ST2. While obviously a bit finicky, it doesn’t look like something I couldn’t do myself. I’ve built four recording studios over the last three decades and have been working on bikes since I was a kid. It doesn’t make sense that if a cable or PCB needs to be swapped out (or even a component replaced on an existing PCB) I need to box up the bike and ship it halfway across the country. With the nearest U.S. Stromer dealer 4 hours away from me, sending it back to Madison would be the better of the two options, but neither is ideal.

When I spoke with Lenny’s on Thursday a tech said this was a known issue. Has anyone here experienced it?

Sorry for the rant. It’s just been an expensive, time consuming odyssey turned obsession, and I just want to ride my damned bike.

First world problems I know...

 

[Neil2018]

Hi, I am having the exact same problem. There is not a single Stromer dealer in Minnesota that is willing to look at this issue. The bike shops that used to carry Stromer Bikes said they are very hard to service and it is difficult to even get parts. They do not want to service my bike.

Stromer said they think it is a motor connector cable. Seeing how I will have to haul this to Crazy Lenny for service, the bike will need to be returned. I hope Crazy Lenny is reasonable and refunds ALL of my money. The bike has 35 miles on it. For the money spent on this bike I and very disappointed.

 

[Chuck E. Cheese]

I just got off the phone with Crazy Lenny's. They are sending the cable directly to me. They made it clear that it should probably be done by a certified Stromer repair center, but I think they might have to say that regarding any repair. There is a very good video on Youtube which shows the whole procedure in detail. It looks like a PITA but seems more tedious and time consuming than truly difficult. There are some very useful tips included in the video and if you decide to replace it yourself you should probably watch it a few times and have it cued up as you do the repair.

Strange as it seems after dropping all that money on a brand new bike, I'm actually looking forward to getting to know the bike better at that level. At some point I'll have to repair it with no warranty support anyway, so I might as well get used to it.

Lenny's has been very helpful to the degree to which the can be over the phone. I knew what I was getting in to when I bought the bike on line, and while I have high expectations for the bike's performance and quality, I understand that stuff happens and things break. I just hope those things are infrequent. It's really an amazing piece of machinery.

I am surprised that another Stromer dealer won't do the repair under warranty. Have you spoken with Stromer U.S. directly? I've only had one experience with them and it was positive. I haven't heard anyone say anything bad about their willingness to assist in situations like ours. New bikes sometimes have issues. Be thankful it didn't fail a day after the warranty ran out. Good luck and keep us posted!

 

[Neil2018]

Thanks for all of the information. I am taking Wednesday off and driving down to Crazy Lenny's to have the cable replaced. I would like to understand the bike better for repairs... as I agree with you that once the warranty is up, I need to be able to try and fix minor issues. But this is way out of my wheel house and I don't want to make the whole situation worse by trying to fix it myself. I just hope this will solve the issue. Len won't take the bike back, and I understand. It isn't his fault that nobody in Minnesota is willing to service the bike, but I can't be running down to Madison every time I have an issue, thus my reason for wanting to return the bike. At this point I would be willing to pay the 15% restocking fee, but even with that Len won't let me return it.

I did talk to Stromer and while they were very nice, they told me to look at their dealer locator for shops in Minnesota. Our large bike shop Erik's is no longer willing/wanting to service them. The were servicing them two weeks ago when I purchased the bike. The other LBS that has sold Stromer bikes is not willing/wanting to service the bike for me. They claim they are very hard to service and get parts for. I am sure I could push harder and maybe get Stromer involved, but I am not sure that will help or hurt my situation. Do I really want somebody who doesn't want to service my bike trying to repair it?

Again this my fault and not Lenny's or Stomer. Knowing that I have zero e bike service experience, I probably shouldn't have bought the bike.

 

[MikeST2]

Yesterday, June 24, 2018 I was returning from the grocery store, descending down a short hill, no recup, just brakes. I made a 90 degree turn to the left at about 2-3 mph, straightened the handlebars and applied pedal pressure. My ST2 (1 month old, 380.7 miles) immediately lost power and started vibrating/pulsing. It became worse with applied torque pressure. I shut the bike off, (motor isolated) and determined it was electrical and not mechanical. Bike weighs 67 lbs and I felt it all peddling the next 5.3 miles to home. Well... it looks like I am experiencing what others have gone through. Service issues, power cable failure, internal motor failure and warranty repairs. For a premium bike this is unsatisfactory reviewing the history that others have experienced. Thinking of returning both bikes to Stromer.

 

[JRA]

Could also be a bad Hall Sensor in the motor itself if not the wire as described.

 

[MikeST2]

Spoke with Joel at Stromer USA, really great guy who answered all my questions about warranty, service and what to expect with Stromer regarding my current electrical failure. It turns out, and I agree with him that unfornately 1 phase of the 3 phase motor has lost connection, most likely the power cable issue, producing dead spots on the stator causing the shudder. At least it all sounds plausible. Joel is sending me two power cables, one for my bike and the other for my wife’s bike. For the repair... I road TREK bikes for many years a developed a rapport with the lead shop mechanic. He has agreed to look at a ‘“YOU TUBE” video that a Stromer advocate posted on replacing the power cable and will let me know if its within his expertise. Unfornutely Stromer will not pay the labor cost. Of note...Got on my TREK DS 8.6 and rode 10.3 miles yesterday with my wife, we both mentioned that it felt like the brakes were dragging and our speed was just a crawl, all the enjoyment was gone. Really miss the Stromer.

 

[Chuck E. Cheese]

Spoke with Joel at Stromer USA, really great guy who answered all my questions about warranty, service and what to expect with Stromer regarding my current electrical failure. It turns out, and I agree with him that unfornately 1 phase of the 3 phase motor has lost connection, most likely the power cable issue, producing dead spots on the stator causing the shudder. At least it all sounds plausible. Joel is sending me two power cables, one for my bike and the other for my wife’s bike. For the repair... I road TREK bikes for many years a developed a rapport with the lead shop mechanic. He has agreed to look at a ‘“YOU TUBE” video that a Stromer advocate posted on replacing the power cable and will let me know if its within his expertise. Unfornutely Stromer will not pay the labor cost. Of note...Got on my TREK DS 8.6 and rode 10.3 miles yesterday with my wife, we both mentioned that it felt like the brakes were dragging and our speed was just a crawl, all the enjoyment was gone. Really miss the Stromer.

Mike-

As I mentioned up above, I had the same the same issue. I opted to do the repair myself. The most difficult part (by far!) is the removal and replacement of the plastic battery sleeve inside the battery door. The video on Youtube will be very helpful for your mechanic when he does the job. Make sure he watches it. I had it on my iPad while I did the work to make sure I was doing things in the proper order. The various screws holding the sleeve (and motherboard and plastic strip on the underside of the tube) are different lengths and need to go back in their respective holes. I used an ice cube tray to sort them as I took them out so I could remember which ones when in which positions. The cable swap was easier than the video made it look. I think it was less than a 10 minute job. The battery compartment was more like an hour. Along with patience and a good flashlight, an allen wrench and a proper bike stand (not the crappy $50 Amazon one I had) are pretty much all you need. Good luck! Let us know how it turns out.

 

[MikeST2]

My ST2 is back and studder free after replacing the power cable from the circuit board to the hub motor, as original. Thanks go out to TREK bikes of Atlanta and Mark the shop mechanic who's is quite a wrench when it comes to bikes. I hope my other Stromer remains stutter free and out of the shop.

 

[Stromer2work]

Having similar issues on my newest ST2x that I bought as a "demo" with less than 150 miles. It now has less than 250 total miles, and I've only owned it for 10 days. It developed an issue this morning on my 8th ride. Riding full out in speed #3 trying to make a red light. Felt and sounded like one if my panniers was rubbing on the tire. I continued riding for a few seconds looking down, and nothing was rubbing. Vibration and noise seems to be electric id nature and seems to be coming from the motor. I pulled over to verify nothing was rubbing. The problem intermittently came and went another 7 times or so times on the remainder of my 10 mile voyage this morning. My fourth stromer, and first serious issue. But only one of my four stromer's has more than 260 miles, so I hope this problem isn't common. Not satisfied at this moment in time. We'll see how Stromer and CL's handles my issue. I am willing to do some work, but did NOT expect it on a new ST2s. I'm hoping this was not a customer return, I don't know why i think they'd do that without disclosing it.

 

[MikeST2]

Sounds like the power cable to the hub motor. Its most likely 1 phase of the 3 phase electrical power driving the motor.

 

[Stromer2work]

Sounds like the power cable to the hub motor. Its most likely 1 phase of the 3 phase electrical power driving the motor.

that's what I gathered reading this thread. I'll ride a backup before I can look at it this weekend. Too many things going on for problems, haha.

 

[lilrich]

Having serviced hundreds of Stromer of all flavors the Syno motored bikes (ST2, ST2S) shutter or some times described as stutter. It will be easily noticed by a definite vibration (feels like an angry vibrator in your seat) when under assist and may also be accompanied by a drive error notification on the Omni (not always). First step is to remove and reinstall the rear wheel making sure that it is correctly oriented, the plug is securely seated and wires routed correctly. Insure correct axle torque. Inspect the plug, connections, axle seating surface and wires for corrosion, damage or strain. After proper installation re-test, if problem is still present the likely culprit is the power cable (wire). Stress when installing or improper routing may have caused a break causing loss of one or more of hall sensing signals. This will cause the drive to stutter or hunt for position. Replacement of the power cable should resolve this. Replacing the cable will involve removal of the wicket (battery box) note position of lower screws as they are slightly different lengths, lowering the controller and unplugging the power and sense plugs. Fishing the wire back through the chainstay takes patience pulling a fish through when removing the old cable is helpful. Use care when pulling the new cable to not strain or damage it and note orientation and routing of all parts before disassembly. Patience and a few choice words and double jointed fingers help too. Good luck I hope this helps.

 

[Chuck E. Cheese]

Having serviced hundreds of Stromer of all flavors the Syno motored bikes (ST2, ST2S) shutter or some times described as stutter. It will be easily noticed by a definite vibration (feels like an angry vibrator in your seat) when under assist and may also be accompanied by a drive error notification on the Omni (not always). First step is to remove and reinstall the rear wheel making sure that it is correctly oriented, the plug is securely seated and wires routed correctly. Insure correct axle torque. Inspect the plug, connections, axle seating surface and wires for corrosion, damage or strain. After proper installation re-test, if problem is still present the likely culprit is the power cable (wire). Stress when installing or improper routing may have caused a break causing loss of one or more of hall sensing signals. This will cause the drive to stutter or hunt for position. Replacement of the power cable should resolve this. Replacing the cable will involve removal of the wicket (battery box) note position of lower screws as they are slightly different lengths, lowering the controller and unplugging the power and sense plugs. Fishing the wire back through the chainstay takes patience pulling a fish through when removing the old cable is helpful. Use care when pulling the new cable to not strain or damage it and note orientation and routing of all parts before disassembly. Patience and a few choice words and double jointed fingers help too. Good luck I hope this helps.

This is the full answer to the problem. There is a video on youtube demonstrating exactly how to do the repair. If you're mechanically inclined and patient it's not too difficult. As I mentioned in an earlier post, removing the battery sleeve (or "wicket" as I just learned) is far and away the most tedious part of the job. Watch the video and consider having it cued up on an iPad or laptop while you do the work. It took me about an hour. I bet I could do it in half the time now that I've done it once. Just make sure to keep the screws in order for putting it back together. It's probably also wise to take some photos as you go along to make sure you can re-route the cables properly. Mine failed after having the bike for a week or so. I've put over 700 miles on it since the repair and it's been flawless.