(gulp)...I didn't think this would be this mysterious.
I just inherited what looks to be a quasi-vintage Bianchi Campione del Mondo (burgundy with celeste decals!), but to the topic at hand. This thing comes with Shimano flightdeck shifter/brake levers and a Sora gruppo.
I'm perplexed at the looseness/tightness combination of the left and right shifters. Here is the combination for the four permutations of highest and low gear for the front and back:
These differences are quite pronounced, with the looseness clearly excessive in both cases. Is there some logic to this that I've just never noticed in other bikes because it may be not qutie as pronounced, or is there something wrong here? And how would I go about adjusting the loose combinations?
Sorry for the confusion. Maybe it's been too long a season...
I never learned to ride a bike. It is my deepest shame.
Some shimano levers only have one marking on them: "Flight Deck"
THis is a bit confusing because this label only indicates that he levers are compatible with Shimano's 'Flight Deck' bike computer that knows what gear you are in.
Flight Deck is not the brand (that is Shimano) or the model (Sora, Tiagra, 105 - most of the examples I have seen that only have the 'Flight Deck' label are Sora or Tiagra, I think).
I still can't imagine what is causing the problem with your shifting. Certainly one of the big improvements that the more expensive components have over entry level ones is shorter lever throw.
Thanks. And now I know that "throw" is the term for that range. It may indeed be that I haven't got enough experience with Sora. Not to say that I'm at the top of the gruppi foodchain, but I don't recall anything like this even on the DeoreLX I had on my Cannondale T9 about 13 years ago. Everything since has been an upgrade
'''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
As mentioned above "Flight Deck" referred to Shimano's proprietary cycle computer. That logo on brifters meant they had an installed wiring harness that connected to the computer to indicate gear position. I have a set of 105 9-speed brifters also marked Flight Deck but have never owned the matching computer and just ignore the wires. It has no effect on their operation otherwise.
I believe Shimano has dropped both the computer and its brifter compatibility from their product line as their current product descriptions make no mention of it.
The shifter; when I say "loose", I mean it has a lot of lateral movement. It has to do with Flightdeck, because that's the brand
If one assumes you mean that the shifter levers, especially the rear have a lot of side to side play then odds are the internals are all gummed up. This especially shows itself where the shifter lever sometimes does not shift and then other times works. Best solution is to wash out the internals with copious amounts of WD40. If that solves your problem, allow the shifter to dry and squirt a small amount of a light weight lubricant. If the washing doesn't work than the shifters are shot and need to be repalced.
I'll try to address your "problem". I'm not sure there is one necessarily, I think your levers are just starting to show signs of wear. According to your matrix here, both shifters are "tight" when the respective derailleur is taking up the slack in the cable (32t and 11T). The shifters are tight because the tension of the cable is directly effecting the shift levers. Conversey, when both shifters have taken in cable, in the 52t and the 27t positions, the cable is being held in an index by a ratchet pawl in the shift mechanism, which is allows the shift levers to have some play to either continue to pull in more cable or let cable out. FWIW, there is no bottom index when the cable is fully relaxed from the shifter- that's the job [in your case, and cases absent of top normal derailleurs] of the low limit up front and the high limit in back coupled with cable tension.
Basically, the shifters are 'tight' when they are directly engaged with the cable tension, and they're "loose" when they're removed from the cable tension, by having the gear selection held by the pawls of the indexing system.
Pretty sure this is normal, but it's probably more noticeable now that the shifters have aged and the bushings have gotten a little sloppier.