fiataccompli
06-10-2016, 02:45 PM
Bearing in mind the subject combination....my race bike (really...pretty much reserved for that only) I just rebuilt after being wrecked last year & not really needing it much for its intended purpose due to a variety of factors (having nothing to do with the bike itself). I purchased it used, but fully functional w/ SRAM Red and a 110 53/36 Rotor Q ring crank setup, in generally workable condition, but about ready for new cables. I had a few issues with chain drop where the chain would go past the catcher and get tightly wedged into place, completely lock the crank & usually require breaking the chain to dislodge. I assumed once fully/freshly cleaned, with new cables & tuning and a re-adjusted chain catcher, I would not have this problem. My 3rd shakedown ride on it yesterday proved otherwise with it dropping twice (truthfully, I'm not 100% certain which direction shift generates it) and getting lodged. The apparent likelihood of having to stop and re-fit the chain in a race makes the bike in effect not a race bike.
So, I can figure out a number of different ways to make this bike reliable. I generally blame the Q-rings and offer the BB area shape of the Cervelo S5 as a contributing factor. I've already had my doubts as to whether I care to keep the Q rings anyway. Nothing I can do about the BB area shape. The crank is a Rotor crank so I suppose others may offer a bit more inner clearance? I guess some blame of the catcher is in order. I didn't have a chance to check to see how much it's out of adjustment now, but surely the act of going past it and trying to work the chain out has screwed that up enough now that there's not much forensic evidence to use.
That's the background. I'm curious whether someone here has a greater wealth of experience than I do with Q-rings, correcting chain drop/using or not using a catcher (I almost think the catcher itself creates this non-recoverable situation)/proper adjustment of the subject setup that perhaps I'm not smart enough to get right yet. If so, i'd love to hear.
Perhaps Q-rings are inherently a complete pain in the neck to tune correctly and I haven't tried hard enough.
I was working on the assumption the previous owner who used the bike for racing did not have this issue (but, then again, it did this basically from day 1)
If this is a phenomenon more associated with chain suck than a front drop when going into the small ring, are Q rings more prone to this as they wear ?(the rings are probably nearing the end of their ideal useful life...thus my earlier thought about just ditching them anyway).
Sorry, that turned out long. If you're still reading & you have some helpful thoughts or want to slap me upside the head for neglecting something totally obvious (wouldn't be the first time!), please let me know. Thanks in advance.
oops, forgot to add: old chain was Shimano, new one is KMC.
So, I can figure out a number of different ways to make this bike reliable. I generally blame the Q-rings and offer the BB area shape of the Cervelo S5 as a contributing factor. I've already had my doubts as to whether I care to keep the Q rings anyway. Nothing I can do about the BB area shape. The crank is a Rotor crank so I suppose others may offer a bit more inner clearance? I guess some blame of the catcher is in order. I didn't have a chance to check to see how much it's out of adjustment now, but surely the act of going past it and trying to work the chain out has screwed that up enough now that there's not much forensic evidence to use.
That's the background. I'm curious whether someone here has a greater wealth of experience than I do with Q-rings, correcting chain drop/using or not using a catcher (I almost think the catcher itself creates this non-recoverable situation)/proper adjustment of the subject setup that perhaps I'm not smart enough to get right yet. If so, i'd love to hear.
Perhaps Q-rings are inherently a complete pain in the neck to tune correctly and I haven't tried hard enough.
I was working on the assumption the previous owner who used the bike for racing did not have this issue (but, then again, it did this basically from day 1)
If this is a phenomenon more associated with chain suck than a front drop when going into the small ring, are Q rings more prone to this as they wear ?(the rings are probably nearing the end of their ideal useful life...thus my earlier thought about just ditching them anyway).
Sorry, that turned out long. If you're still reading & you have some helpful thoughts or want to slap me upside the head for neglecting something totally obvious (wouldn't be the first time!), please let me know. Thanks in advance.
oops, forgot to add: old chain was Shimano, new one is KMC.