chain skipping over the bosch CX SES sprocket problem plus motor noise issue

mcmars

New Member
Hi everyone, not sure if I have posted before, but I am having a problem with my chain skipping over the small sprocket on bosch performance line CX on a 2019 haibike allmtn 6. Guessing I did something wrong as today I removed rear wheel to set up wheels for tubeless and when I got it all back together the chain was not engaging on the small sprocket and was skipping over top of gears. I did not bother releasing the clutch on the derailer to make it easy to remove the wheel, maybe the clutch got engaged somehow and I need to re check that?? I did remove and clean up the small retainer the chain goes through that is directly over the tiny sprocket after I had the problem, but that did nothing. I figure it is likely something I messed up and someone here might know what I did. I can try local bike shop tomorrow, they have a couple of scott ebikes and I think they have the same bosch driveline.

I might be having a seal issue with the motor, but doubt that could be related. I got the bike in late Nov 2019 and got a couple of weeks of riding in before a major foot surgery that kept me on crutches most the winter. About a month ago, when I felt brave enough to try a light ride, the motor was very loud for an easy flat 20 mile mostly paved ride, whirring, grindy noise. When I got home I sprayed the smallest bit of Triflow lub into the bearing area on right side of crank and the noise went away. I have only been able to ride a couple of rides since as I am barely able to wear shoes still post surgery. Bike only has about 140 miles total and I have never sprayed a hose at it, just hand washed it a couple times carefully with a washrag. I stored bike in climate controlled garage upright over winter. I live it desert SW of US where it is dry, maybe I bombed a couple mud puddles last fall, but I try my best to avoid them. Hoping I am not having seal issues, but kinda think that is happening as today I got a dry rag into the seal area as it was pretty dirty and the dirt/sand was mixed with a pretty heavy looking lube which I can only guess came from the inside of motor. I use a very light and dry chain lube to keep things clean, only lubed it twice now and always wipe it down after applying. I thought I would mention this issue as I know there is a seal problem with these motors. It would be under warranty, but nearest shop for haibike is couple hours away and I mail ordered bike from out east.

Thanks for any help! I have enjoyed reading some of the posts here to learn about the bike, seems like a great bunch. I am enjoying this bike and while being laid up, I bought a 2017 Bulls cruiser bike that had 4 miles on it and have been using that on pavement more last few weeks as I am still recovering my foot. The bulls is very nice with the first Gen Brose motor and 8 speed shimano afine rear hub w shimano disc brakes. Not as powerful as the bosch CX , but silent, smooth and easy to out pedal the limiter without feeling the "anchor" like I do with the drag of the bosch. Loving the ebikes!
 

rich c

Well-Known Member
Have you measured chain stretch? Trying to remember if that chainring is a wide narrow style. You might check chain engagement to make sure that isn't the issue. I think it is. It's just a matter of moving the roller chain over a link so the rollers settle down into the teeth.
 

mcmars

New Member
I was wondering about chain stretch just a few minutes ago, I can measure it. So with the narrow wide I might just have to manually move the chain to another link? I can't believe I could stretch it out with 140 miles, but I like to ride some nice trails and blasting uphills that I could never do before has been fun on the E bike. Maybe time for a nice high end KMC E bike specific chain? Not sure what haibike puts on that bike, but they likely are saving some money and going with lower end one. Thanks for help!
 

rich c

Well-Known Member
I was wondering about chain stretch just a few minutes ago, I can measure it. So with the narrow wide I might just have to manually move the chain to another link? I can't believe I could stretch it out with 140 miles, but I like to ride some nice trails and blasting uphills that I could never do before has been fun on the E bike. Maybe time for a nice high end KMC E bike specific chain? Not sure what haibike puts on that bike, but they likely are saving some money and going with lower end one. Thanks for help!
It's a matter of having the inner plates and the outer plates on the correct tooth.
 

mcmars

New Member
Haha, it was the small narrow wide SES cog misaligned with the chain links. Easy fix to flip bike upside down, open up the chain retainer by cog, and move chain to mesh with the proper tooth. I was fighting 40MPH winds and sandstorm yesterday, much easier this beautiful morning.

I got a good look at the greasy axle area and it sure look likes the seal into the bosch motor is failing and loosing grease and oil. If anyone has some links for me to understand this, I would appreciate your help. I am concerned the noise I was hearing first ride this year was corrosion in the motor? Maybe on Monday, I can have local friendly LBS take a peek and maybe they know if there is a way to improve the seal. I got some shorter crank arms to put on I sourced from Miranda over the winter to help with the pedal smashing rocks issue. I might have LBS pull the old cranks and do a good inspection and clean up for me to see what is happening with the motor seal. I am betting bosch has figured out a better seal solution by now to keep from having to replace failed motors from a bad seal?

I also got a new icetech front rotor on yesterday to replace the already warped TRP one. And installed a nice 730mm chromag bar I had in my garage to replace the huge 780mm haibike bars. Thinking I replace the 55mm haibike stem this morning with the 40mm thompson stem I had in garage to make the downhills a bit easier, no problem climbing on this bike. Getting it tweaked!
 

Mike TowpathTraveler

Well-Known Member
I don't believe your local friendly is going to "improve" the seal that Bosch engineers designed and manufactured. What you need to do is to thoroughly clean the Tri-Flow you sprayed in the area around the seal, as well as the rest of the motor and ride it for a few rides, minus going into mud puddles, to monitor how much if any grease is escaping your seal. Right now, what that lube is doing is creating a slurry of dirt and sand in the area of the seal and shaft.ing rocks. You're not doing those plastic gears within the motor case any favors with pedal strikes, so you'll need to address that with some more careful riding or shorter crank arms after any warranty work is attempted cause you just might find your warranty voided if the original cranks are replaced....

Take a look at the Warranty section on the Haibike USA site. It appears you can take your bike to any authorized dealer for warranty work. Best to double check with them and/or the original seller before moving forward. That info should also be included in the owners manuals you got for your bike.

The Park Tool youtube site is a treasure trove of information on how to perform basic bike repairs competently. Worth a check. Good luck and let us know the outcome.
 

rich c

Well-Known Member
There is this video, but as soon as you remove those dollops of silicone on the bolts, the motor is all yours, no warranty.
I think I've linked to this video at least a half dozen times .
 

mcmars

New Member
I don't believe your local friendly is going to "improve" the seal that Bosch engineers designed and manufactured. What you need to do is to thoroughly clean the Tri-Flow you sprayed in the area around the seal, as well as the rest of the motor and ride it for a few rides, minus going into mud puddles, to monitor how much if any grease is escaping your seal. Right now, what that lube is doing is creating a slurry of dirt and sand in the area of the seal and shaft.ing rocks. You're not doing those plastic gears within the motor case any favors with pedal strikes, so you'll need to address that with some more careful riding or shorter crank arms after any warranty work is attempted cause you just might find your warranty voided if the original cranks are replaced....

Take a look at the Warranty section on the Haibike USA site. It appears you can take your bike to any authorized dealer for warranty work. Best to double check with them and/or the original seller before moving forward. That info should also be included in the owners manuals you got for your bike.

The Park Tool youtube site is a treasure trove of information on how to perform basic bike repairs competently. Worth a check. Good luck and let us know the outcome.

Thanks Mike for your advice. I love the park videos and use them frequently for repairs and adjustments. I ordered the tool to remove the bosch lockring between the cranks and the seal so I can access the area where the axle goes into the motor for cleaning and inspection. I bet I put 2-3 drops of triflow in that area at most, so the triflow should not be a problem. What it did tell me is there is a problem with the seal and the motor was source of noise as the triflow was able to get beyond the seal and made the motor noise go away, for now. I am very much a finesse rider and have been riding mtn bikes since 1983, and I am doing my best to not whack pedals, but this is first bike I have ever had an issue with pedal whacks. Internet search has told me I am not the only one having pedal strike issues on this bike, it seems to be the biggest complaint, and many others have gone to shorter cranks on this bike. I already changed out some of the rubber dampers to tune the rear shock to keep it from bottoming out as it was stock and have the suspension aired up and adjusted for my weight and gear. That helped quite a bit, but it still is too low for "normal" riding IMHO and I should be able to pedal without constantly skipping pedal strokes and reversing my pedals to avoid rock strikes. I cannot even bank the bike through smooth sandy corners and pedal without bottoming out and I know that is not right. I cannot believe shorter crank arms would void a warranty, but I will look into that aspect before I change them out. I will call the shop that is 2 hours away and discuss my noise issue and also let the dealer I bought the bike from know I have some motor noise.
 

mcmars

New Member
Step #17 shows packing thick silicone grease around the axle/bearing interface. I suspect this is the thick grease I am getting on my shop rag mixed with dirt, sand and black chain gook. I have a tub of some expensive performance line ceramic grease that is super thick and I bet it would be a good choice to pack into this area every few hundred miles to help keep water out of the motor.https://www.performancelinebearings.com/wp-content/uploads/2018/07/boschperformancelinebearingchange-watermarked.pdf
 

rich c

Well-Known Member
Step #17 shows packing thick silicone grease around the axle/bearing interface. I suspect this is the thick grease I am getting on my shop rag mixed with dirt, sand and black chain gook. I have a tub of some expensive performance line ceramic grease that is super thick and I bet it would be a good choice to pack into this area every few hundred miles to help keep water out of the motor.https://www.performancelinebearings.com/wp-content/uploads/2018/07/boschperformancelinebearingchange-watermarked.pdf
Are you suggesting packing grease around a seal from the outside? That won't do much in my opinion. A layer of grease on a rotating shaft is not a seal. A new seal is the way to keep water out. If there is water inside already, the damage has been done and the bearings will only get worse. Keeping more water out will only provide a minimal change at best.
 

Mike TowpathTraveler

Well-Known Member
McMars: Riding an mtb since 1983 puts you into or near my age and puts us both at a time when the mountain bike craze was just starting to ramp up. Here on the east coast, I bought a Ross mtb, black frame, gold anodized rims, the bees knees short of a Specialized Stumpjumper. Welcome to ebiking and the Haibike community. That All Mountain 6 is a top tier mtb, imo.

That bike has the Haibike idler gear pulley and it would help to make certain this is not the source of your sounds as I believe another poster with that upper idler gear on their Haibike was making noises.

I have a Haibike Full FatSix, with the Yamaha PW drive. Over 10 thousand miles; just completed a 66 mile road ride today with a wee bit of NJ Pine Barrens riding tossed in.

2 different animals, the Bosch and Yamaha. Something to consider is to never go through water up to the cranks. I've never have, and though I've ridden in my fair share of rain, some of it monsoon quality; as well as some snow rides, whenever I've come up to a puddle in the middle of my trail rides, I either turn around or bypass it. These motors will perform fine in rain conditions, followed by a nice wipe/dry down. But they are not made to endure total motor immersion.

I'd not put any silicone grease around the crank either as it's going to attract alot of dirt and sand towards that seal.

Let us know what the dealer says come Tuesday when they open back up after the Memorial Day holiday.
 

mcmars

New Member
Thanks Mike for the advice, you might be right on the idler gear being the source of the noise. The noise is gone for now, but it felt like a very loose and dry bushing when I was messing with it to get the chain re-aligned onto the narrow-wide teeth. I think I will see about replacing the bearing as I see there is an aftermarket bearing available, as if it is is a bearing, then it is shot. Maybe I take it apart and see what is going on with the idler bearing/bushing and try and get some silicon lube into it? We are in a pretty bad drought here in SE Utah now, so be easy to avoid water. We had a few rains last fall and there was one ride I recall having to pedal just next to some humongous mud puddles, but I never really got into the thick of it.

I really like most aspects of this bike, my first Ebike, but it could lose the idler and some pounds. I think it deserves some shimano xt brakes and ice tech rotors, at least I did not have to change out the tires, I love the minions DHF 2.8. No issues so far with the battery capacity, seems most technical rides of less than 20 miles are enough for me now at my age and fitness, that would not be the case if I was 20 again. I seem to always come home with 2-3 bars left after spending the day in EMB mode.

My first mtn bike was the original cannondale, it was quite a burly rigid beast, but was only thing really out there at the time. Looks like this site is easy to attach some pics, here are some pics I took over the weekend. You can see a few ergonomic mods that I had in the garage. The stem is 40mm and makes it much easier on the downhills, bars are straight 730mm and saddle is very comfy WTB deva.
 

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DanInStPete

Active Member
Great looking bike, amazing place to ride. You mentioned southeastern Utah, where about? I did a trip to that area once - Zion, Bryce, Lake Powell, St. George. Love it, want to go back.

I have that saddle also, best saddle I've found.

I had SES pulley issues recently and the fix was shortening the chain. It took a month to figure it out and I fixed it by accident...
 
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