Hi Forumites!
Hopefully you guys can give me some insight as to what I'm missing:
Bike is well maintained, 10 speed 105 shifter, 10speed 105 rear derailleur, jagwire cable and housing. The 10spd cassette teeth are in good shape. Chain is in good shape. Jockey wheels spin freely, teeth seem unworn, and they engage the chain well. It's a ten speed chain, but not shimano. Chain is the right length.
Bike wouldn't shift properly on the cassette. I noticed that the cable tensioner was extend all the way out and wobbly. I ran it in and re-tensioned the cable so it was snug in the highest cog with the shifter in the most slack position. I didn't have much trouble getting it to shift crisply on the stand, but when rode it it would shift to lower gear (increased tension) smoothly, but when shifted to higher gear (decreased tension) it would hesitate and then klunk into place. Once shifted, it didn't make any complaining sounds, shift out or skip under high torque or anything else abnormal. But I found the shifting unacceptably rough for 105. Adjusting it to the point were it will shift to higher gears smoothly would result in lack of cable pull to shift to lower gears at all. I played with the dwell and it didn't significantly help. I have the b screw set so it doesn't rub but maintains the jockey wheel close to the cassette as it shifts. I tried it at various intervals before ending here.
I measured the chain, it's around 3 on a progold chain gauge. I measured its width with vernier calipers to make sure it was a 10spd chain and it matched an unused shimano 10spd chain I had. All links operate smoothly. I cleaned and relubed the chain and it didn't really help. The cable pulls smoothly and seems properly routed. The housing is all cut flush, as far as I can see. All the ferrules are in good shape. They are 4mm plastic. I couldn't find any weak parts on the housing or cable, unless it's under the bartape.
My only conclusion is I'm either missing something or the shifter itself is having some problem.
Thank you for any help, I really appreciate it!
