Stromer ST2 Pulsing (Please vote)

Does your Stromer "pulse" when peddling at a constant speed, on a flat surface, in Mode 3?


  • Total voters
    35

John ware

Active Member
Hey Mitchell, I know you and your dealer have been very thorough in your evaluation of the "pulsingate" and possible root causes, but I thought it might be good idea to confirm firmware versions.

Here's mine. I keep thinking this sounds as much like it could be a software issue as it is a hardware. I want to believe that somewhere in Switzerland all these 1000s of bikes are feeding some database about their performance. And at some point we will see fresh algorithms that further smooth the power curves up and down.

image.jpg
 

Berlin

New Member
Hey Berlin:


DEFINITION OF MY PROBLEM: What happens to me is I am peddling at a steady rate, on a flat surface, moving between 15 and 20 mph and applying a constant pressure to the pedals. It feels like the assist mode is cutting in and out. For example I will feel the assist for about 4 seconds, then its like assist has been turned down (not completely off) and the peddles have resistance. The peddles require more pressure. After applying that pressure for about 2 to 3 seconds the assist comes back on and there is no longer resistance.
Dear Mitchell,

Now the good news:
My bike is restored after the REAR BRAKE sensor was replaced (in warranty) - following the engine problem.
Everything is going perfectly.

I've test run the bike 2 weeks (approx. 500km) and for the moment I have no more problems, the first impressions are very good.
No more hitches, he is "sharper", my ST2 runs now like he should ride – very smooth, absolutely a very nice feeling.
Even the speed is a little bit higher as before (in mode #2) and the reduction of the battery level is several percentage better.(= less reduction – I have the impression)

I find it strange that such a small issue has such a big impact. After resolving this issue, you only know how it really is ‘driving with ST2’.
Frankly, I felt let down, and I even hesitated to sell the bike.

But now all doubts are gone.

Ps: And indeed in a very very low speed (not a continuous frequency), there is still a hick up, but this is not an issue for me
Hopefully for the ST2 owners (and potential buyers) this pulsing problem resolved quickly

Greetings
 

opimax

Well-Known Member
I noticed when the pulsating is in effect the power level icon on the display goes on and off in time with the pulsating. In other words the display also shows what i feel. The above post from Berlin describes exactly "1000%" of what i am experiencing.

Where is the the sensor , in the brake handle? so i could effectively get rid of the issue by disconnecting the electronics on the handle bars to test?
 

Ravi Kempaiah

Well-Known Member
I noticed when the pulsating is in effect the power level icon on the display goes on and off in time with the pulsating. In other words the display also shows what i feel. The above post from Berlin describes exactly "1000%" of what i am experiencing.

Where is the the sensor , in the brake handle? so i could effectively get rid of the issue by disconnecting the electronics on the handle bars to test?
When I was installing my OMNI, I had to disconnect everything and reconnect. Yes, both brakes have sensors and when OMNI boots up, it checks for signal response from torque sensor, battery, brakes, lights, regen etc
We could disconnect and reconnect to see what's going on....
 

opimax

Well-Known Member
Tonight on my 4th long ride I rode 1/2 way with the rear brake cut off switch disconnected , I must say the bike ran great, no bouncing , faster , and just about what I was hoping for. Now to make arrangements to get this repaired. It is a subtle but almost night and day to me
 

David Hutches

New Member
I have experienced what I think you're describing on my last three rides (each between 15 and 20 miles) will cruising along between 12 and 15 mph in Eco, City, and Tour modes on flat land on my ST1, with 2 different batteries. Everything is going fine but it begins to feel like you're suddenly pulling a fairly heavy trailer--almost but not quite the same feeling as turning the power of entirely. For a second or so you begin to get back to normal but then the same sensation comes back and it stays that way for several minutes before gradually getting back to normal. I've tried: shutting down and restarting, removing and reinserting the battery, stopping for 10-15 minutes, and even unplugged the control unit and both brakes for a few seconds and then reconnecting. I am going to take it to the dealer new weekend for a look, but I've only ridden 390 miles and I just hope it isn't one of those weird things that no one can figure out. Any thoughts on this would be greatly appreciated!
This describes exactly the problem I started having this afternoon with an ST1 that has just a little over 300 miles on it. The morning commute was fine; the afternoon one was painful because of the erratic pulsing behavior. Based on other forum comments, maybe it's an issue with the weight from the panniers (though this is the first time this has happened), so I'll double check everything tomorrow morning and see if it repeats, first without, then with the panniers. Failing that, will contact the dealer. If the torque sensor is is adversely impacted by panniers attached to the stock rack, then it sounds like a potential design problem.
 

Ravi Kempaiah

Well-Known Member
Tonight on my 4th long ride I rode 1/2 way with the rear brake cut off switch disconnected , I must say the bike ran great, no bouncing , faster , and just about what I was hoping for. Now to make arrangements to get this repaired. It is a subtle but almost night and day to me
Need to try this and see if it makes any difference on my bike.
 

Berlin

New Member
Tonight on my 4th long ride I rode 1/2 way with the rear brake cut off switch disconnected , I must say the bike ran great, no bouncing , faster , and just about what I was hoping for. Now to make arrangements to get this repaired. It is a subtle but almost night and day to me
@opimax
I didn 't expect it worked by simply disconnecting the brakes. (but look, the better)
Happy to hear that you feel a big difference. I am also very pleased that my local dealer has replaced the brake sensor.
For the moment three weeks and 800km further; and still no holdups

Indeed a small difference but almost night and day:cool:
Hopefully the problems get solved for everyone with this issue.
Ps: When I put my bike in, my mechanic established that there was indeed a faulty brake sensor - so I guess they can easy measure these things out
 
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fxr3

Active Member
Now my st1 is infected! Sat for about a month- took it out and it pulsed! Didn't make it very far-turned around and jumped on st2. but it will be at dealer soon to have it fixed.
That is totally irritating, and makes bike worthless. I underestimated all the smack talk on pulsing. It's far worse than I imagined.
 
I owned an IZIP E3 Dash for a short time until the weather got cold enough to reduce the range to an unacceptable level. I was riding it 27 miles 1-way to work on the W&OD trail. I also experienced the pulsing folks are describing here. Both pulsing and range drop occurred within a week of each other, and when I arrived at home with less than 1 mile of range remaining I decided to trade it in (got a Trek Domane 4.5...very nice). But, I have the ideal long distance bike commute (living and working very close to the W&OD) and I hate the traffic in Loudoun/Fairfax. So I finally had my first test ride on the ST2. I wasn't as blown away by the e-bike sensation as one who'd never ridden an e-bike would be. The E3 Dash is pretty quick. However, the ST2 is noticeably better and incredibly more refined (the Tesla of e-bikes). I've read every post in this thread. In total, it's kind of shaken my confidence in the ST2....or more to the point - made me nervous about dropping $7k on a bike with a thin dealer network and looking at the prospect of needing to utilize the generous Stromer warranty, perhaps more than a few times.

But....one thing I try to keep in mind is that people generally go online and visit forums to 1) do research, or 2) find what's wrong with their car/bike, etc. and post about their problems. It's kinda like the the News...you aren't going to turn on the TV and hear "A passenger jet took off from LA this morning and landed in New York safely this afternoon." So...I'm wondering how many hundreds? thousands? of ST2 owners are out there and not posting about their awesome ST2 because they are having too much trouble-free fun and smiling on their way to work.

Thoughts? All machines have problems, and I feel for those who've had these pulsing issues, but I'd like to know how statistically significant these occurrences really are - before I spend $7K.

Note...I do agree there are "normal" pulsing behaviors that are due to the tension being weak on the chain and the motor cutting in and out, but I do think people are experiencing real problems due to failed or misaligned sensors, etc...things that will need to be addressed by dealers (which are a mixed bag).
 

opimax

Well-Known Member
I live near mile marker 8.5 or 5.0 depending on which direction you are headed , you may come try mine if you like.

We have a 1 and a 2
 
I live near mile marker 8.5 or 5.0 depending on which direction you are headed , you may come try mine if you like.

We have a 1 and a 2
Thanks for offering an opportunity to test ride both a 1 and 2. It would be nice to see if I would be happy with a 1 and use savings to buy a spare battery, and more.

For now I'm mostly interested in getting a truer sense of ST2 consistency/reliability. I'm very curious to know if common nature of internet forums is at work here....meaning people with problems post questions about problems or express frustrations with problems, while perhaps the majority of owners aren't visiting forums because their bikes are working fine. If we knew how many ST2 (or even ST1) have been sold we would have our answer. The problem with forums is they distill and concentrate all the mishaps and the "lemons". Less than 10 people posting about their similar problems can give a strong wrong impression about bike reliability -- even while statistically insignificant, or within the range expected for any high-end complex machine, people freak after reading several reports of problems and run away.
 

BTB

Member
I have an ST2 Sport and my wife has an ST2 Comfort. We don't have pulsing problems. I've never bought a new car that didn't have a warranty issue at some point, so I wouldn't be disappointed about having to take a Stromer into the shop. A Stromer, like a car, utilizes sophisticated technology, so things can go wrong. Being located within car driving distance of a Stromer dealer made it an easy decision to make. Knowing that Stromer stands behind its warranty was also essential. I think it's a great bike and a great company. I think they need to do more to promote their bikes and brand, but for an engineer-centric company, it's very impressive.
 
My ST2 has 1975 miles on it and so far no pulsing. The rear wheel is starting to slip in the rain. Might need a new break pad? Otherwise all errors have been human.
 

opimax

Well-Known Member
Storm trooper , I also want to try your bike to verify we have the same pulsating issue. Mine has a buzzy/vibration feel along w/excessive on off when in level 3. I hope you take me up on the offer. I will come to you if you would rather.
 

ChrisL

New Member
I've only had my ST2 a couple of weeks but I've already got about 250 miles on it and I have had zero issues with pulsing. Also, I "thought" I had an issue with the daytime light. In my effort to resolve it I emailed Stromer (and also found this site). It was a simple settings adjustment, but I did hear right back from Stromer within a business day and also received follow ups. So far I'm very impressed with Stromer customer support considering they're basically located halfway around the planet from me.

As far as...
My ST2 has 1975 miles on it and so far no pulsing. The rear wheel is starting to slip in the rain. Might need a new break pad? Otherwise all errors have been human.
If you're not familiar with hydraulic disc brakes (I'm also an avid Mtn. biker) just note that it's a good idea to keep an eye on your pad wear. New brake pads are cheap and simple to install, but new rotors are not cheap and much more of a pain to deal with. Pad wear is extremely unpredictable since it's dependent on all kinds of conditions (i.e. terrain, rider weight, riding style, etc...), but I'd think beyond 1000 miles is a good marker to at least be "aware" of your wear ;).

Also if you're slipping in rain (presumably while starting from a stop?), it's not nuts to think that it could be time for a new rear tire. Tire wear, like brake pad wear, is also highly variable and dependent on conditions. I'd think that 2000 miles would be on the lower side for tire life, but not at all unreasonable if you're tough on them.

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Opimax -
The bike with pulsing issues was a 2014 Izip E3 Dash. I thought it was the bottom bracket spinning and cutting the wires to the torque sensor, or one of the bad motors that were a common problem with all of the 2014 models. I returned it and got a Domane 4.5 which is the most comfortable road bike I've ever ridden.

I should have left my screen name for someone else to snag, because last Saturday I ordered a 2016 Specialized Turbo X. It felt more like a bike, I could get it in a small frame size that fits me perfectly, the assist is extremely seamless, and I spent a lot less money. I ride 40 to 80 miles a week on my Domane, so doing more of the work is a plus. It seems that Specialized was shooting for a feeling that is less like riding on a high powered machine, and being more a seamless feeling that feels like riding a regular bike....encouraging more rider input. It does. It feels a lot like a regular bike because assist comes on very progressively. It never feels like the motor is doing most of the work. This took a lot of finesse to dial in.

I still like the Stromer ST2 for a lot of reasons. If price were same as the Turbo I'd pick the Stromer for the battery/range and the GPS tracking. But the Turbo won the ride feel and price point. Quality felt equal (extremely high on both).
 

Ron Bez

Member
Opimax -
The bike with pulsing issues was a 2014 Izip E3 Dash. I thought it was the bottom bracket spinning and cutting the wires to the torque sensor, or one of the bad motors that were a common problem with all of the 2014 models. I returned it and got a Domane 4.5 which is the most comfortable road bike I've ever ridden.

I should have left my screen name for someone else to snag, because last Saturday I ordered a 2016 Specialized Turbo X. It felt more like a bike, I could get it in a small frame size that fits me perfectly, the assist is extremely seamless, and I spent a lot less money. I ride 40 to 80 miles a week on my Domane, so doing more of the work is a plus. It seems that Specialized was shooting for a feeling that is less like riding on a high powered machine, and being more a seamless feeling that feels like riding a regular bike....encouraging more rider input. It does. It feels a lot like a regular bike because assist comes on very progressively. It never feels like the motor is doing most of the work. This took a lot of finesse to dial in.

I still like the Stromer ST2 for a lot of reasons. If price were same as the Turbo I'd pick the Stromer for the battery/range and the GPS tracking. But the Turbo won the ride feel and price point. Quality felt equal (extremely high on both).

That's exactly how I have been discribing my 2016 Turbo base model. How's the suspension seat post? I've been using the Thudbuster which I like, but I need to rebuild it already, just over a year old. About 4k of road miles and I'm only 150lbs..... I guess I'm not thrilled with its durability. Specialized probably won't sell the post off the bike...... Congratulations on your new X!
 
I've completed two 54 mile commutes on the Turbo X. I've had a Thudbuster on another bike, and I think I like the spring loaded and bushing dampened one on the X more. Really impressed with the new Turbo X (2016). I'll post more about it in a different thread.