Sduro Yamaha PW-SE clunky pedal engagement.

#1
I've just bought a Haibike Sduro fullseven 6 LT ebike and it's great. However, after doing 30 miles I've noticed that the pedal engagement is quite clunky. If I'm freewheeling and then peddle there is a loud clunk as the pedal engages the drives. I can feel it through the cranks. It's more noticeable when dabbing the pedals. If I spin the back wheel and then move the cranks until they engage I can feel the clunk every time. It feels like quite a hard clunk. Is this normal for a Yamaha engine ? The engineer in me says no. I compared it to a new bike and the new bike has a clunk but much softer.

This is also posted in the Yamaha forum.
 
#2
I've just bought a Haibike Sduro fullseven 6 LT ebike and it's great. However, after doing 30 miles I've noticed that the pedal engagement is quite clunky. If I'm freewheeling and then peddle there is a loud clunk as the pedal engages the drives. I can feel it through the cranks. It's more noticeable when dabbing the pedals. If I spin the back wheel and then move the cranks until they engage I can feel the clunk every time. It feels like quite a hard clunk. Is this normal for a Yamaha engine ? The engineer in me says no. I compared it to a new bike and the new bike has a clunk but much softer.

This is also posted in the Yamaha forum.

I can confirm the same on Yamaha PW-X. This is due to the fact they have no torque sensor if my memory serves me right.
 
#3
I'm curious about this as well. It seems my perception of the 'clunk' developed after I scraped a pedal of my Sduro FullNine 6.5 (I think that's the PW-X motor) firmly against some tarmac while riding to the grocery store. I'm having a tough time finding discussions with real answers about it online. Maybe I can get a video of it going on youtube and post it here. It feels like the drive engagement pawls would be a suspect. They ratchet on freewheel but spring outward to engage the motor drive when pedaling, but to my understanding there are only two or four pawls, depending on the model.

I took my bike to the LBS and they tightened the motor mounts, and said everything seems to be fine with the way the motor drives. My initial thought is to go hit some rocky trails and give it a stress test.

To address net200777's remark, I think the PW-X does have a torque sensor, but I say that anecdotally. When I pedal harder, I get more output on the meter on the display, so I believe this lends credence to my hypothesis.
 
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LimboJim

Active Member
#5
I put 700 trail miles on a 2016 Allmtn+ with a PW motor before I sold it, and never experienced clunky cranks. The buyer has put another 500 miles on it since with no such problems.

Early this year, however, I got a 2017 Hardnine 4.0 (also PW) that developed the same thing you're all describing after about 40 (mostly) road miles. In my bike, it seems to be most prevalent at 15-20mph. I'll be watching this thread to see if any of you figure it out.

For now, I've chalked it up as a cheaper bottom bracket issue that I'll just have to hope doesn't get worse; the place I got it on clearance from is 3000 miles away! I hope you folks bought yours closer to home, and that your dealers can resolve the problem.

Please post again when you do! Thx
 
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#6
I'm curious about this as well. It seems my perception of the 'clunk' developed after I scraped a pedal of my Sduro FullNine 6.5 (I think that's the PW-X motor) firmly against some tarmac while riding to the grocery store. I'm having a tough time finding discussions with real answers about it online. Maybe I can get a video of it going on youtube and post it here. It feels like the drive engagement pawls would be a suspect. They ratchet on freewheel but spring outward to engage the motor drive when pedaling, but to my understanding there are only two or four pawls, depending on the model.

I took my bike to the LBS and they tightened the motor mounts, and said everything seems to be fine with the way the motor drives. My initial thought is to go hit some rocky trails and give it a stress test.

To address net200777's remark, I think the PW-X does have a torque sensor, but I say that anecdotally. When I pedal harder, I get more output on the meter on the display, so I believe this lends credence to my hypothesis.

Yes you are correct, I meant to say shift sensor. I think that's what haibike told me.
 

LimboJim

Active Member
#9
Update on my formerly clunking Haibike Sduro w/Yamaha PW:

I wanted to see if something in the drive unit sounded loose, so I removed all the motor mounting bolts (labeled "22Nm") and carefully pulled the unit from the bike. First I had to remove the right crank, and everything was tight except one of the motor mount bolts. It didn't seem loose enough to cause a clunk, but it was easier to loosen than the other ones.

When I shook the motor, it sounded solid. I re-mounted it and tightened the mounts to 22Nm. I reinstalled the crank and took the bike for a nice long ride. I'm not sure what step in that process fixed it, but the clunking is gone! Maybe it was just that motor mounting bolt, and I pulled my crank and motor unnecessarily 🙄
 

Brooks

New Member
#10
Ya, I had something similar, but it was a swishing sound. Took it back and they removed those motor mounting bolts one at a time, put lithium grease on them and re-torqued. Been fine ever since. They have to be fairly tight.
 
#11
I've just bought a Haibike Sduro fullseven 6 LT ebike and it's great. However, after doing 30 miles I've noticed that the pedal engagement is quite clunky. If I'm freewheeling and then peddle there is a loud clunk as the pedal engages the drives. I can feel it through the cranks. It's more noticeable when dabbing the pedals. If I spin the back wheel and then move the cranks until they engage I can feel the clunk every time. It feels like quite a hard clunk. Is this normal for a Yamaha engine ? The engineer in me says no. I compared it to a new bike and the new bike has a clunk but much softer.

This is also posted in the Yamaha forum.
Try the Yamaha YDX Torq ebike.
There is NOTHING CLUNKY at all about it. Its super smooth. Unfortunate that so many brands are mis-applying Yamaha's great technology. Thankfully Yamaha is now building the motor and the bike TOGETHER, so that everything is a perfectly tuned and properly matched, and accurately applied.

The Haibikes I've ridden are rather clunky and bulky feeling period. Its too much about just slapping a motor on for a lot of these e-bike OEMs. Motors should not be expected to overcome the 'ills' of the heavier and bulky bike. Unfortunately that is what much of the industry has been doing for the better part of the last 5 to 7 years. Yamaha is one of the few to strive to overcome this, where you have a real bike that is eminently rideable WITHOUT the motor, and so when the motor is used in assist mode, its totally natural, non-intrusive, not overwhelming (or underwhelming), and truly an extension of the rider. Zero resistance against the rider. Other OEMS will eventually get there, once they understand what Yamaha is doing, but Yamaha's at least a good 2 to 3 years ahead of everyone else with their entire line up. Consider, Yamaha built the very first e-bike in 1989, commercialized them in Japan in the early 90's, and has shipped more than 6 MILLION drive units since. They've taken their time, getting everything right, and the belated intro to the US market with their line up is well worth the wait. the timing is actually excellent as the ebikes are becoming much more mainstream, and more avid cyclists are starting to appreciate the benefits, and finding models that are similar in road worthiness as their higher quality bikes they have been used to riding. More mainstream, (but less frequent) riders, that are recreational, or havent been on a bike in years, have been the bulk of the buying population here in the US for ebikes. We are on the precipice of that change, as finally the weights are getting lower, efficiency much higher (i.e. 70 to 80 miles on only 36 Volts and 500 wh's.), and the better components are being applied on more reasonably priced ebikes.
 
#13
I can confirm the same on Yamaha PW-X. This is due to the fact they have no torque sensor if my memory serves me right.
Nope that is not true. (sorry)

Yamaha uses on their PW-SE and PW-X motors, and for sure on their own ebikes, the following:

Yamaha Triple Sensor System
The key to Yamaha's smooth and powerful assist is a "triple sensor system." The three sensors are:
1. Torque sensor that detects pedaling power,
2. Speed sensor that detects the bicycle's speed, and
3. Crank sensor that detects the number of rotations through pedaling.
All 3 sensors work together to instantly detect the running conditions, the movement of the rider with precision, delivering a renowned smooth and powerful assist. The most natural and organic feeling drive on the market.

By the way, most torque sensors by themselves, are rather suspect at providing accurate response, and a not insignificant number of them fail in a relatively short period of time, especially if they are not integral to the motor (i.e. bottom bracket torque sensors, rear hub torque sensors, etc.) Usually the torque sensors used on most other brands of ebikes, especially those priced below $3000, are nothing more than barely glorified 'strain gauges'. These can also easily get out of calibration. And who actually knows they need to get their 'strain gauges' (torque sensors) re-calibrated ? (usually more cost than anyone wants to spend, or simply hard to do, depending on where the ebike OEM put it, so that means you are better off getting a new one). Anyway, without the right design, and without the right level of software, along with other corresponding sensing, the experience of torque sensing can be a lot less than desired in as little as the first few hundred to a thousand miles. Maybe a season of use? Plus Yamaha's own ebikes and their torque sensors are auto-calibrating.

So Yamaha's system on their own ebikes, is entirely different, and a lot more robust and accurate in a number of ways. For one, their speed sensor is integrated in the rear hub, much more accurate than placing a speed sensor at a bottom bracket or on a motor, where variances can occur. The response timing to a rider's pedaling is unparalled right now versus any other brand of ebike, including what Haibike or Giant is doing. Their overall system (upgraded gear components, shafts, better software) also greatly reduces backlash, which again, over time the backlash on other less thoughtfully applied motors to the ebike, can increase and get worse. You'll feel that on older Bosch's, or Brose's, or Shimano's. People will often think their motor is 'failing.' Actually it has to do with how the gears are designed, where 'play' develops, and the timing software used cannot compensate, and it has no other sensor to determine needed software algorythm adjustments. Over time, this eventually decreases reliability of the motor.

The absolute precision in a Yamaha will help it last years, besides performing very smoothly.
 

Brooks

New Member
#15
Take your BS and GTFO this thread. The OP had a problem with his Yamaha powered Haibike and it was resolved. Go advertise your Yamaha hardtails somewhere else, this is the Haibike forum........YOU ARE POSTING INAPPROPRIATELY