problem EX1

[vham777]

Hi @ all

i'm having some trouble with my EX1. i am riding the meta power 29 2018 with ex EX1, and there is a terrible noise comming from the cassette when pedaling in 4th and 5th gear (counting from the hardest gear).

does anyone have an idea what this could be? i did about 400-500kg with it, cassette still looks fine to me.
i am posting a video and some pics from the cassette, maybe somebody can help me out with it

thank you all
Mirco

 

[vham777]

sorry, that didn't work out well posting the video - will try it later again with some lower resolution, file is too big

 

[ccrdave]

gears not indexed properly
B screw not set correctly

 

[vham777]

sorry, i did not describe it well then. the shifting is going fine like the first day, there is absolutely no noise in the other gears

 

[Geoff]

The drive train probably just needs tuning. There could be a few things that need checking. Off the top of my head the most common causes I can think of:

• Derailleur cable tension not properly adjusted,
• Derailleur hanger not correctly aligned - usually the problem if you can't get a consistent shift/gear meshing across the entire cassette. This is done with a tool such a Park Tool DAG (Derailleur Alignment Gauge)
• Derailleur cable inner binding inside cable outer - replacing the cable inner can fix this but sometimes replacement of inner and outer may be required,
• B-Screw adjust needs attention - distance between upper jockey wheel and cassette is possibly too great.

 

[vham777]

@ geoff and ccrave, many thanks for your inputs, will check all that this evening

if you can please listen / look at the video, i never heard a noise like that on a drive train...

 

[ccrdave]

sorry its very hard to tell from that but are you sure its not coming from the motor? it sort of sounds like a bearing noise but not sure from that short clip

 

[vham777]

i don't think it comes from the motor, as it is still there as i turn off the motor and pedal only myself. and it is only in 4th and 5th gear, no matter how hard i pedal in the other gears...

 

[ccrdave]

if it were a motor bearing the noise would still be there with the motor off but it is strange its only in those two gears. are you sure the chain is not rubbing on something just when its in that position, chain guide maybe?

 

[Geoff]

I'm leaning toward it being a derailleur hanger alignment issue just because the problem is most evident in the middle of the cassette. Has the bike fallen over or been crashed and subsequently taken a hit on the derailleur?

Can you post a picture of the derailleur taken such that we can see if the cage is contacting the cassette and eliminate the B-Screw adjustment allowing the upper jockey wheel to contact the cassette in those specific gears.

The other possible point that noise could emanate from is the chain guide but thats unlikely in this case as the noise is occurring only in the middle of the cassette.

Do you have the opportunity to put the bike in a work-stand (no suspension load) and see if the noise is still there?

 

[Geoff]

Does it sound like the chain is "skipping on" rather than "meshing with" the cassette in the affected gears?

 

[vham777]

Does it sound like the chain is "skipping on" rather than "meshing with" the cassette in the affected gears?

Hi Geoff, i did not hit anything with the derailleur (or i am not aware of it ), chain is not skipping, it rather sounds as if something was "hitting or touching" elsewhere... i will post a foto of the derailleur later today

many thanks again!

 

[Mabman]

When the chain is in the middle of the cassette it has no side load on it and if it is worn enough it will sometimes make noise without the side load adding tension to the links. I would try swapping in a new chain even it that one only has few miles on it.

 

[vham777]

well i checked everything through again and all seems to be ok to me

@Mabman thanks for that input, i just ordered a new chain. after all this seems to be the most logistical source of the noise to me

 

[Geoff]

When the chain is in the middle of the cassette it has no side load on it and if it is worn enough it will sometimes make noise without the side load adding tension to the links. I would try swapping in a new chain even it that one only has few miles on it.

I"m doubting that it is the chain as @vham777 has said that the "chain is not skipping". I had been leaning toward it being a derailleur hanger alignment issue until the noise was described as "hitting or touching".

 

[Geoff]

well i checked everything through again and all seems to be ok to me

@Mabman thanks for that input, i just ordered a new chain. after all this seems to be the most logistical source of the noise to me

View attachment 6092 View attachment 6093

Do you have any pictures taken from this angle with the wheel in and the bike in gear where the noise is occurring? I'm hoping to see how close the jockey wheel is to the cassette. It could be hitting if the B-Screw is not correctly adjusted. SRAM may have a very specific measurement with respect to jockey wheel to cassette spacing. I know this applies to their 12 speed Eagle stuff and since this derailleur looks very similar I suspect the same applies to the 8 speed EX gear too.

Are you sure the derailleur has not taken a hit? The shift cable end is missing and there is what possibly looks like a scratch on the bottom edge of the lower hinge. It doesn't take much to put a derailleur hanger out of alignment (they are designed to bend/snap) and it's not easy to see until you put an alignment gauge on it. Any good bike shop mechanic should have one but personally for the amount of use it gets you are better off having your own. Yes, for what it is, a DAG is not cheap but it is one of those tools that you will be glad you have in your toolbox.

A few weeks ago I was having chain noise issues on my brand new 2019 Kenevo Expert that had been in my possession for just one day. It's fitted with 11 speed SRAM GX. Cable adjustment did not help as I could not get the chain to shift properly across the entire cassette. The chain was noisy and skipping in the middle range of the cassette. Not what I was expecting on a brand new bike. Anyway, I installed my DAG tool and found that although alignment of the hanger was good in the vertical plane it was out by over a centimetre (measured at the at the wheel rim) in the horizontal. If you have never used a DAG tool before - you are using the wheel rim as a frame of reference for aligning the derailleur hanger thus the rim needs to be checked for trueness before you get started. Once the misalignment of the hanger was corrected the shifting issue the associated chain noise was gone.

 

[Kernow]

Almost for sure it will be the b screw tension , all of ours came with no where near enough clearance , have a look here , about half way down it shows the clearance setting being done with a template , but the gap is 22mm and easy to measure . It needs setting at your normal sag too , so iether get someone sitting on the bike or let the shock down to 30% sag before checking the gap
How to Correctly Adjust the Rear Derailleur on Your E-mountainbike | E-MOUNTAINBIKE Magazine

 

[Kernow]

Also check the lock ring on the cassette is tight , they all seemed to work loose on early use but were fine after tightening properly .

 

[njn]

I had the same creaking issue in the middle gears and resolved it with a little grease. Take the cassette off and grease the spacer. The spacer is captured, so it's a bit tricky to clean and grease it.

 

[vham777]

Hi @ all
so, everything has been checked through again, B-screw set up fine. derailler alignment looked fine too. finally i demounted the cassette, cleaned & greased everything and set it up again, aaaand no noise there anymore.

on the other side, i do not hear the free wheel's (is that the english word???) noise either now, don't know if that is good or not it's the first time i removed a cassette and working on the free wheel, but everything is at its place again, i just put in quite a bit of grease there

sometimes working on the bike is like fixing one thing, then following by a new problem... i switched from a specialized enduro s-works to commencal, just to not having the most fanciest pricy silly carbon stuff to fix. but ebiking enduro style is not actually "preserving" the components the forces on them seem to be even stronger than with a normal bike, and i do lot more rides with the ebike now!

 

[Kernow]

Hi @ all
so, everything has been checked through again, B-screw set up fine. derailler alignment looked fine too. finally i demounted the cassette, cleaned & greased everything and set it up again, aaaand no noise there anymore.

on the other side, i do not hear the free wheel's (is that the english word???) noise either now, don't know if that is good or not it's the first time i removed a cassette and working on the free wheel, but everything is at its place again, i just put in quite a bit of grease there

sometimes working on the bike is like fixing one thing, then following by a new problem... i switched from a specialized enduro s-works to commencal, just to not having the most fanciest pricy silly carbon stuff to fix. but ebiking enduro style is not actually "preserving" the components the forces on them seem to be even stronger than with a normal bike, and i do lot more rides with the ebike now!

Too much grease in the freewheel is not good , if it’s gone quiet that an indication of too much .

 

[Ducatijones]

Just had same probs with 4th & 5th gear using sram ex1, Bike is 3 weeks old and done 150 miles around the mountain. Really bad creaking sound when climbing using 4th & 5th gear. Removed the cassette which was not torqued up enough, cleaned, greased and put back. It sounds like a swiss watch now. Job done happy days, but something to keep an eye on perhaps.

 

[Kernow]

Just had same probs with 4th & 5th gear using sram ex1, Bike is 3 weeks old and done 150 miles around the mountain. Really bad creaking sound when climbing using 4th & 5th gear. Removed the cassette which was not torqued up enough, cleaned, greased and put back. It sounds like a swiss watch now. Job done happy days, but something to keep an eye on perhaps.

Mine came loose when it was new , if the adjustment isn’t correct and the chain drops off the end cog it can undo the retainer ring