Power Pulsing, Continued

[Steve Plattner]

I took my ST1 in for a checkup at 500 miles. The only real complaint was the pulsing issue. When I got it back it seemed a bit better, though the mechanic didn't really seem to have an explanation about what he'd done.

Since that time I have encountered the problem and lately it has been getting much worse. Again, as I pedal in Eco, City or Tour mode, it's as if I were suddenly pulling something heavy--my momentum is retarded and it feels almost as if all power is off for a few seconds or several minutes at a time. Last night it happened again -- my battery level was at 76%. 5 miles later it had dropped only 2% to 74%, so it feels like the power isn't getting to the motor or it's getting to it very inconsistently. I have tried 3 different fully charged batteries--two purples and my gold battery. Problem happens with all three. So not a battery issue either in my opinion.

One other thought--very interested in your take on this--at 500 mile checkup the mechanic told me my brakes were quite worn for a bike with my mileage. Granted, the bike was 62 lbs., and I weight 222, so it carries quite a load. I also live in a hilly city and frequently go down hills at 25 mph, so maybe that's all that's going on with the brakes. Still, I wondered if the rear brake somehow stays or comes on when it shouldn't and whether that could be the cause of the pulsing/power drop off?

It's getting a little frustrating.

Thanks.

 

[Deleted member 803]

You can contact Joel Montecalvo, Service Mgr. at Stromer ([email protected]) and ask if he would help your dealer do some troubleshooting. Electrical issues are not always easy to resolve but intermittent power certainly sounds like either a connectivity issue, a controller issue, or a torque sensor issue. I'd even have them check a faulty brake. Stromer is very good about working through issues with dealers. Not all Stromer dealers have equal experience dealing with these issues. Anything man made can have defects. I am sure that when you get to the root cause, the resolution will allow you to enjoy years of use. Good luck!

 

[Berlin]

I took my ST1 in for a checkup at 500 miles. The only real complaint was the pulsing issue. When I got it back it seemed a bit better, though the mechanic didn't really seem to have an explanation about what he'd done.

Since that time I have encountered the problem and lately it has been getting much worse. Again, as I pedal in Eco, City or Tour mode, it's as if I were suddenly pulling something heavy--my momentum is retarded and it feels almost as if all power is off for a few seconds or several minutes at a time. Last night it happened again -- my battery level was at 76%. 5 miles later it had dropped only 2% to 74%, so it feels like the power isn't getting to the motor or it's getting to it very inconsistently. I have tried 3 different fully charged batteries--two purples and my gold battery. Problem happens with all three. So not a battery issue either in my opinion.

One other thought--very interested in your take on this--at 500 mile checkup the mechanic told me my brakes were quite worn for a bike with my mileage. Granted, the bike was 62 lbs., and I weight 222, so it carries quite a load. I also live in a hilly city and frequently go down hills at 25 mph, so maybe that's all that's going on with the brakes. Still, I wondered if the rear brake somehow stays or comes on when it shouldn't and whether that could be the cause of the pulsing/power drop off?

It's getting a little frustrating.

Thanks.

@Steve Plattner

On the other thread regarding 'the pulsing problem' I posted the following;

Dear M.,

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

My bike is restored after the REAR BRAKE sensor was replaced following the pulsing problem.

After this pulsing issue is fixed, I'm riding the bike for ± 6 weeks (approx. 1000km) and for the moment I have no more pulsing problems.
My bike runs very good for the moment, absolutely a very nice feeling.

For me it was definitive the brake sensor. (and in my cases the rear brake sensor)
Hopefully your pulsing problem will be resolved quickly, this is more than just annoying
Greetings

 

[Steve Plattner]

@Steve Plattner

On the other thread regarding 'the pulsing problem' I posted the following;



My bike is restored after the REAR BRAKE sensor was replaced following the pulsing problem.

After this pulsing issue is fixed, I'm riding the bike for ± 6 weeks (approx. 1000km) and for the moment I have no more pulsing problems.
My bike runs very good for the moment, absolutely a very nice feeling.

For me it was definitive the brake sensor. (and in my cases the rear brake sensor)
Hopefully your pulsing problem will be resolved quickly, this is more than just annoying
Greetings

Thanks, I suspect there's a pretty good chance that this is what my problem is, or likely could be. I am going to take it to my dealer on 9/26 when I go on vacation and try and get him work through it and also get in touch with Stromer for advice. May encourage him too to have a rear brake sensor available in needed.

 

[Steve Plattner]

You can contact Joel Montecalvo, Service Mgr. at Stromer ([email protected]) and ask if he would help your dealer do some troubleshooting. Electrical issues are not always easy to resolve but intermittent power certainly sounds like either a connectivity issue, a controller issue, or a torque sensor issue. I'd even have them check a faulty brake. Stromer is very good about working through issues with dealers. Not all Stromer dealers have equal experience dealing with these issues. Anything man made can have defects. I am sure that when you get to the root cause, the resolution will allow you to enjoy years of use. Good luck!

Great advice, and special thanks for providing the service manager contact info at Stromer. I hope to drop my bike off at the end of this month and leave it with my dealer so he can resolve this while I am on vacation. More and more I suspect the rear brake sensor base on the symptoms.

 

[Berlin]

Great advice, and special thanks for providing the service manager contact info at Stromer. I hope to drop my bike off at the end of this month and leave it with my dealer so he can resolve this while I am on vacation. More and more I suspect the rear brake sensor base on the symptoms.

Did you have a good vacation?
I was wondering if your bike has been in for a maintenance
I' am very curious if your pulsing problem was pinpointed and resolved?

My stromer runs for the moment very good. No more pulsing problems, very smooth ride.
With a good cadence its a dream to ride - without a lot effort my ST2 runs aprox 25 miles per hour in mode #2 and i can do a bit more that ± 60miles per battery charge

 

[Steve Plattner]

Did you have a good vacation?
I was wondering if your bike has been in for a maintenance
I' am very curious if your pulsing problem was pinpointed and resolved?

My stromer runs for the moment very good. No more pulsing problems, very smooth ride.
With a good cadence its a dream to ride - without a lot effort my ST2 runs aprox 25 miles per hour in mode #2 and i can do a bit more that ± 60miles per battery charge

Berlin, we did have a great vacation, thanks. My bike has been with my dealer for 2 weeks. Didn't seem to make too much progress while I was gone but we've had a couple of calls about it this week. He has now spoken with the Service Manager at Stromer--not sure if it was Joe Montecalvo--and so far they don't feel it is brake sensor-related. He suggested it might be due to my riding for long periods in Eco or City, and if I would switch up or down when the problem occurs, they thought the bike would adjust immediately. I explained that I have done that every time, but to no avail--doesn't make a difference what power setting it's in. He's looked at the motor but doesn't feel it is the issue, and has checked the wire and the brake lever assembly too. After talking with Stromer, they thought it could somehow be related to the gears on the rear hub--apparently if they aren't tightly aligned or something, it could be an issue and could create the symptom I have seen many times. Anyway, I should get it back after I return from another trip on Wednesday. I really hope they solve it. I am losing a lot of great weather/time on my bike at this time of year! Will keep in touch.

I really like the idea of 60+ miles per charge. My ST1, with me and a few accessories abroad, is 300 lbs. But the purple batteries gives me about 25 miles of range of level ground, and the gold battery offers a bit over 30 miles--my three batteries have averaged about 15 charge cycles so far--not that much. 60 would be much better.

 

[opimax]

I am following this thread very closely, please post EVERYTHING you find. BTW i did almost 80 last night on my wife's st1 . 3 gold batteries worth of mostly POWER , great ride, avg just under 20. I am at about 285-300 w/bike and accessories