Rough shifting

[ers]

Hi,

I have a Rise M20 with SLX drivetrain that I feel shift pretty rough while shifting down the casette (to a smaller gear). Is this normal? Shifting up to an easier gear i pretty smooth even under some pedalpower but down isn´t.

Feels like the entire rear end are moving sideways when shifting under even a tiny amount of power. And yes, the bikes only done 900km/600miles and I can´t find any worn bearings or linkages...

On my analog bikes it´s usually the other way around when shifting under power...

 

[steve_sordy]

@ers the answer is simple. Do not shift under power!

I know that the professional racers do it, but they get a new drivetrain after every race or two, and don't have to pay for it. One of the new drivetrains (can't remember which) can be shifted under power but it's expensive.

Backing off the power so that a smooth shift can be made needs to be learned. But once I learned it, I found myself psychologically incapable of shifting under power. I'm an engineer, I have mechanical sympathy and the crunching and clanging noises make me cringe.

You need to still keep pedalling to make the shift, just back off the pressure for a second or two.
If you are climbing and get caught out needing to go to a larger gear, but don't want to back off the power in case you lose momentum, then shift up a power mode for a few seconds to allow you to surge a bit, then you can safely back off and shift. Once shifted, then you can drop down to the previous power mode.

 

[Mikerb]

as you change to smaller cogs so the chain becomes slacker. If your chain is well broken in you may find you can now re adjust the B tension which would help. You should also check the pivot points on your mech are wel lubricated and that the clutch has sufficient tension.

 

[ers]

Yeah, I been riding mtb for many years now so shifting without applying power is no news to me, I´m just supprised by the vertical (feels like) movement of the rear when doing it. And I´m not applying much power at all...

Just replaced the chain and adjusted the B tension. I´ll look in to the clutch on the rear mech...

Or maybe I just have to live with it...

 

[Mikerb]

Confused by what you feel in terms of the back end of the bike movement when changing gear. Initially you said it felt like a sideways movement.......then above you said vertical movement. You said you checked pivots and bearings.......have you checked freehub bearings? A collapsed outer bearing on the freehub might explain your feeling of movement and gear change issues moving to the smaller cogs.

 

[ers]

Confused by what you feel in terms of the back end of the bike movement when changing gear. Initially you said it felt like a sideways movement.......then above you said vertical movement. You said you checked pivots and bearings.......have you checked freehub bearings? A collapsed outer bearing on the freehub might explain your feeling of movement and gear change issues moving to the smaller cogs.

My misstake, I mean sideways / horizontal movement. Will check the freeshub bearing and switch wheels and test...

 

[Weeksy]

My misstake, I mean sideways / horizontal movement. Will check the fresshub bearing ond switch wheels and test...

I with above, i simply don't understand what you're feeling... Every time you change gear it feels like the bike/frame/something moves sideways ?

 

[ers]

I with above, i simply don't understand what you're feeling... Every time you change gear it feels like the bike/frame/something moves sideways ?

Correct, feels very odd but only manifests when shifting to smaller cog nothing when going to larger so outer freehub bearing seems plausible...

 

[Stihldog]

It’s easy to clunk or crunch those gears with an eMTB in turbo while climbing. I’ve done it, during a climb, when I can’t stop my momentum. The sound is horrible.

Besides the suggestion, B-screw, freewheel bearings or pawls, check the derailer hanger for proper alignment. Btw, some derailer hangers ca be installed incorrectly.

There’s some other derailer options but those can start to become expensive (Sram T-type, Shimano/ SRAM combo). Also a slight pause during shifting and the correct cadence can help …if everything is setup properly.

I have the T-type SRAM system on one of my bikes. Power shifting is possible during a climb but I still avoid that whenever possible. I can’t believe how smooth and quiet shifting can be.