Check the B tension Spring to make sure the chain is tight enough.OldZaskar said:A bit miffed here - my Shimano XT rear derailurer (new) has started to ghost shift. Specifically, it'll drop to the smallest (lower numerically) cog when I hit a bump (hard tail). This happens often but not constantly and not on large bumps... I'm an XC guy - no big hits
What makes this odd, is that otherwise, the rear and front derailures are shifting perfectly - no rattle/chatter, no dragging, no hesitation, etc. Just smooth, crisp shifts. I hate to start messing with the tension.
Is the chain loose? Is it hopping because of this? Drop two links? Or is it in the tension - back off bit?
Drivetrain:
F: Shimano LX
R: Shimano XT
Chain: Sram
Cassette: Shimano LX
Thoughts?
"Bump Shifting" - drops to smaller cog
A bit miffed here - my Shimano XT rear derailurer (new) has started to ghost shift. Specifically, it'll drop to the smallest (lower numerically) cog when I hit a bump (hard tail). This happens often but not constantly and not on large bumps... I'm an XC guy - no big hits 
What makes this odd, is that otherwise, the rear and front derailures are shifting perfectly - no rattle/chatter, no dragging, no hesitation, etc. Just smooth, crisp shifts. I hate to start messing with the tension.
Is the chain loose? Is it hopping because of this? Drop two links? Or is it in the tension - back off bit?
Drivetrain:
F: Shimano LX
R: Shimano XT
Chain: Sram
Cassette: Shimano LX
Thoughts?
What makes this odd, is that otherwise, the rear and front derailures are shifting perfectly - no rattle/chatter, no dragging, no hesitation, etc. Just smooth, crisp shifts. I hate to start messing with the tension.
Is the chain loose? Is it hopping because of this? Drop two links? Or is it in the tension - back off bit?
Drivetrain:
F: Shimano LX
R: Shimano XT
Chain: Sram
Cassette: Shimano LX
Thoughts?
1 - 17 of 17 Posts
New?
possibly a little cable stretch?
possibly a little cable stretch?
Bent hanger is what I'd check first.
I second the hanger, also bad hub......(loose)
Try 1/4 turn out (unscrewing, increasing housing length) on the rear shifter's cable adjuster. if still a problem then another 1/4 more out. If this adjustment causes skipping or won't shift down easily into the next smaller cog then this is too much adjustment, then go back to where it was, you my have another issue.
Be sure your cable housings are not older than 1 year of frequent riding or they could be very worn inside and pinching the cables and causing irregular shifting effects.
Good luck!
Be sure your cable housings are not older than 1 year of frequent riding or they could be very worn inside and pinching the cables and causing irregular shifting effects.
Good luck!
is the rear a shadow?
What's up with the Shadow Dan0? I have a shadow - my drivetrain has been doing this for a couple weeks, hanger is fine, as is chain, cassette, hub... I've been suspecting it's the derailleur...dan0 said:is the rear a shadow?
Nothing's up with shadow, shadow wouldn't cause this problem. Did you check your hanger with a hanger alignment gauge? With the power of my e-speculation, I would say your problem stems from needing new shift cable and housing if the hanger truly is straight.Rollin'in'Zona said:What's up with the Shadow Dan0? I have a shadow - my drivetrain has been doing this for a couple weeks, hanger is fine, as is chain, cassette, hub... I've been suspecting it's the derailleur...
I have had this happen on my FS when the middle length of housing is too short. It could also be grubby cables/housing.
plus 1 on Pisgah
Sticky cables give you delayed shifting.
Sticky cables give you delayed shifting.
the cable on the shadow needs to be about 1/2" longer than you think, even though you get rid of the loop of cable you still need a bit of slack. Its more noticeable on bikes with rear suspension but I've seen it happen on hardtails tooRollin'in'Zona said:What's up with the Shadow Dan0? I have a shadow - my drivetrain has been doing this for a couple weeks, hanger is fine, as is chain, cassette, hub... I've been suspecting it's the derailleur...
e speculation or not if the rear cable on the shadow is too tight(short) it will shift on rough terrainzebrahum said:Nothing's up with shadow, shadow wouldn't cause this problem. Did you check your hanger with a hanger alignment gauge? With the power of my e-speculation, I would say your problem stems from needing new shift cable and housing if the hanger truly is straight.
I run full-length housing, and it's on the longish side.dan0 said:the cable on the shadow needs to be about 1/2" longer than you think, even though you get rid of the loop of cable you still need a bit of slack. Its more noticeable on bikes with rear suspension but I've seen it happen on hardtails too
Yeah, the hanger is straight (I have more Park tools than the LBS).zebrahum said:Nothing's up with shadow, shadow wouldn't cause this problem. Did you check your hanger with a hanger alignment gauge? With the power of my e-speculation, I would say your problem stems from needing new shift cable and housing if the hanger truly is straight.
I run full-length housing on this bike, and other than the derailleur, the housing is the only component that hasn't been replaced in the past few months.
Try changing out your cables and housing. Full length housing can be good for keeping grub out, but it can also be good for keeping grub in.
1 - 17 of 17 Posts
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