Sduro yamaha all mtn SC 2016 motor issues when climbing

Duke em

New Member
I have been taking my bike out on technical rides a bit above my skill level.
There's usually some steep climbs up muddy power line roads/paths...

I have noticed that when on a long climb where I have lost momentum and the forward motion is purely dependent on my pedal power, the motor will inconsistently assist me when going up the steep muddy hill.

I think it's an issue with my pedal cadence being really slow. Although I'm on the lowest gears of a 2x10 gear setup, the mud plus the steep climb puts me at a slow pedal cadence. I'm applying a LOT of torque on the pedals to climb; albeit maybe not consistently every second of the climb since there's maybe a deficit in my athleticism. I feel the motor assist just turns off half of the time during that steep muddy climb. In those moments I feel the full monstrosity of riding a 50 lbs bike up a muddy steep path. And I end up getting off the bike and pushing bike up the muddy path. THAT's exactly when the ASSIST WALK mode would definitely help!!! And my Sduro 2016 bike has that function disabled!!

Is this the torque/cadence difference between a yamaha motor ebike vs the Xduro Bosch motor ebikes?

From the comments I read about the Xduro Bosch, I'm guessing even at a low cadence, the motor assist will consistently continue to power the wheels as long as you apply a little torque.

I feel the Sduro Yamaha is lacking in this dept.
 
I have been taking my bike out on technical rides a bit above my skill level.
There's usually some steep climbs up muddy power line roads/paths...

I have noticed that when on a long climb where I have lost momentum and the forward motion is purely dependent on my pedal power, the motor will inconsistently assist me when going up the steep muddy hill.

I think it's an issue with my pedal cadence being really slow. Although I'm on the lowest gears of a 2x10 gear setup, the mud plus the steep climb puts me at a slow pedal cadence. I'm applying a LOT of torque on the pedals to climb; albeit maybe not consistently every second of the climb since there's maybe a deficit in my athleticism. I feel the motor assist just turns off half of the time during that steep muddy climb. In those moments I feel the full monstrosity of riding a 50 lbs bike up a muddy steep path. And I end up getting off the bike and pushing bike up the muddy path. THAT's exactly when the ASSIST WALK mode would definitely help!!! And my Sduro 2016 bike has that function disabled!!

Is this the torque/cadence difference between a yamaha motor ebike vs the Xduro Bosch motor ebikes?

From the comments I read about the Xduro Bosch, I'm guessing even at a low cadence, the motor assist will consistently continue to power the wheels as long as you apply a little torque.

I feel the Sduro Yamaha is lacking in this dept.
I rode 6 hours yesterday on a very similar terrain with tons for muddy uphills, I experienced what you describe only once and all other climbs were great. You are right if you don't have enough cadence the bike will not help you much, but once you learned how to operate it properly (high cadence) - it works flawlessly. It's like any other bike, all of they are not perfect and have shortcomings, but I feel this one is very very good.
 
I have been taking my bike out on technical rides a bit above my skill level.
There's usually some steep climbs up muddy power line roads/paths...

I have noticed that when on a long climb where I have lost momentum and the forward motion is purely dependent on my pedal power, the motor will inconsistently assist me when going up the steep muddy hill.

I think it's an issue with my pedal cadence being really slow. Although I'm on the lowest gears of a 2x10 gear setup, the mud plus the steep climb puts me at a slow pedal cadence. I'm applying a LOT of torque on the pedals to climb; albeit maybe not consistently every second of the climb since there's maybe a deficit in my athleticism. I feel the motor assist just turns off half of the time during that steep muddy climb. In those moments I feel the full monstrosity of riding a 50 lbs bike up a muddy steep path. And I end up getting off the bike and pushing bike up the muddy path. THAT's exactly when the ASSIST WALK mode would definitely help!!! And my Sduro 2016 bike has that function disabled!!

Is this the torque/cadence difference between a yamaha motor ebike vs the Xduro Bosch motor ebikes?

From the comments I read about the Xduro Bosch, I'm guessing even at a low cadence, the motor assist will consistently continue to power the wheels as long as you apply a little torque.
I feel the Sduro Yamaha is lacking in this dept.

Actually, it's the other way round.
Bosch is designed for higher cadence support and Yamaha is designed for instant-torque low-mid cadence. The newer PW-X version of Yamaha assists all the way upto 110rpm and is supposed to be very good. I haven't tested in myself.

Here is what the director of sales for Haibike had to say about the Bosch Vs Yamaha.


Hub motors are lot more forgiving but the mid-drives are so much dependent on the rider's shifting skills and cadence rhythm. Not trying to be condescending here but mid-drives make you a better cyclist for sure because if you're in the wrong gear, the whole system just feels sluggish. Assist cutting out has to do more with the rider than the motor's glitch.

Their new Yamaha is supposed to be better than Bosch with higher-cadence support and much wider torque band.


Last summer, we were making a detailed video on the Sduro All Mtn series and because of other projects, it fell through but based on my testing, you have to maintain certain cadence irrespective of the climb. You really don't have to get off the bike at all. That's really not necessary.
Are your climbs tougher than this guy?

 
Thank you for your input Ravi.

It clears up things a lot! Much appreciated!!!!

Duke
San Diego, California
 
Thank you for your input Ravi.

It clears up things a lot! Much appreciated!!!!

Duke
San Diego, California
I have a 2016 Sduro Trekking which has a 1x10 drivetrain. I just got back from some mild singletrack riding and can confirm that the torque drops out if you get spots where you're letting off your own pedal power. It's certainly manageable if you can keep a pedaling rhythm up, but if you're at the point where the lowest gear in a 2x system still has you totally bogging down, you may be hitting a hill that just doesn't want to be climbed!
 
I'm waiting for my Sduro Trekking SRX. To make sure it was OK on hills, during the demo I took it up a 1 mile stretch with an average grade of about 14%, with some peaks at 18%. I had no major issues, despite being some 200 pounds. But that was on paved roads. It sounds like this system isn't really good at off-road stuff. Although I won't be doing a lot of that, I'll definitely being climbing tons of hills, some of which contain short steep sections.

Hope I bought the right bike... You guys are getting me worried here. :D
No worries, you'll be fine. I ride mostly pavement, including a long, steep climb back to my apartment..there's plenty of power. What the OP is describing sounds like some seriously hardcore mountain biking on trails too steep for any non-powered bike to climb.
 
The main issue with the Sduro Mtn Bike yamaha motor cutting out for me was when going on a steep off road climb on a muddy path that normally isn't possible with a regular non-powered mtn bike. It also seems barely possible with a motor assisted e-bike as well.

Issue coming from the assist dependent on maintaining cadence as detected by spinning of the rear wheel. When going uphill on a muddy path, the rear wheel cadence in my case gets very low. The mud and uphill gravity causes me in many causes to move forward by few inches at a time here and there, despite me applying a lot of torque. In those instances of slow cadence and high torque, the motor cuts out despite me really needing it, cause I'm not moving forward enough for the cadence sensor to allow the motor to assist me. So then I'm trying to pedal a 50 lb bicycle up a muddy path without motor assist.

I end up walking the heavy bike up the steep muddy hills. And the walk assist mode on the 2016 sduro mtn bike is disabled to boot. Just not a good situation.

I would be willing to pay for a swap out of the motor to get the walk assist function working on my darn bike.
 
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Reading this thread brings out some interesting figures and it peaked my curiosity. I live in the Appalachian mountains and there is no shortage of hills.
About the steepest hill I have found without looking deliberately, is the paved road leading up to our house. Whenever folks go for a walk they always fuss about what it takes to get home. From the bottom to the top where my house is, is a bit under 300 yds or 300 metres. Its what we walk down and then back up again to go to the mailboxes. (often in the car or riding mower LOL).
I took my trusty spirit level which is 48" long (1.219 m) and a tape measure down and took some measurements using the gauge level. Quite often I found a 9" climb in 48" but one area I found a tad more than 10" and thankfully near the top it levels out a little and gets down between 6" and 7".
By my reckoning, our hill is between 19% and 21% over a length of 200 yards and its closer to 13-14% over the "easy" section LOL.
With our Sduro Trekking bikes we both come up that hill (my wife at 140lbs easier than me 204lbs) in "high" on the Yamaha assist with the chainring of 38t and one down from the biggest rear sprocket which is 32t.
Needless to say, to be faced with that after a long ride is a bit daunting and will need a rest before tackling it :) Walking up it in ice and snow is dangerous!
 
That would be nice LOL. I like that idea :) However there is a support down there with 12 mailboxes on it for the whole road and they are done that way to conform with the Rural Mail Statutes. The mail man delivers the mail with a special right hand drive Subaru (4x4) and gets all the mail boxes in one go through the right hand side front window. A system used throughout USA I think, outside the cities anyway.
Every now and again I get a mail package that's too big to go in the mailbox and he has to drive up the hill and ring the bell. That slows them down however and if its too often they make a fuss !!
 
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