Thanks for info. I'll look for a chain watcher. Didn't know rear derailleur could be damaged when coaxing chain back onto a front chain ring with front derailleur.
"David L. Johnson" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
David Storm said:
By the way, I consider this a Trek defect. That wussy little chain stay protector is stuck on with a glorified scotch tape...not meant to last very long and certainly not fit to take the brunt of a tearing chain.
Of course it's not. Such a "protector" is only meant to keep a loose chain (imagine a slightly sticky freehub) from scratching the stay, not to prevent damage when you 1) drop the chain completely and 2) don't stop.
Two recommendations: If you drop a chain, stop and put it back on by hand. I have seen people sheer off rear derailleurs trying to coax a chain back on. Secondly, to keep it from dropping on the inside, get a "chain watcher". Great gizmo.
--
David L. Johnson
__o | Let's not escape into mathematics. Let's stay with reality. -- _`\(,_ | Michael Crichton (_)/ (_) |
Well, my worst fear occurred with my new Trek 5500. When approaching a steep hill, I shifted the Dura-Ace triple into the small chain ring and it plopped right off on the inside. I quickly shifted up and kept on pedaling to coax the chain back on. This time, however, the chain backed up from the bottom tearing off the metal chain stay protector and scraping the chain stay. What I ended up with is a shallow gouge on the outside of the chain stay just behind the bottom bracket. A few frayed carbon fibers stuck out. I took the bike to LBS where I bought it. They said the damage was iffy, and they would send the frame off to Trek if I wanted for a closer inspection (which they assured me would they would replace under warranty if necessary). Alternatively I could ride it for a while to see how it stood up as it was not clear if there was any structural compromise in the chain stay. I opted for the latter. They glued the metal guard back on and sent me on my way. I've ridden it only 50 miles since then, including a ride up and descent down 3800 ft Mt Diablo in the East SF Bay area yesterday. It seems to be OK no sign of failure, but I keep going in my head what somebody told me, "If any carbon fibers show it's [censored]." Any opinions? Should I send it off to Trek now or give it a while and pretend I'm Lance.
By the way, I consider this a Trek defect. That wussy little chain stay protector is stuck on with a glorified scotch tape...not meant to last very long and certainly not fit to take the brunt of a tearing chain.
By the way, I consider this a Trek defect. That wussy little chain stay protector is stuck on with a glorified scotch tape...not meant to last very long and certainly not fit to take the brunt of a tearing chain.
Of course it's not. Such a "protector" is only meant to keep a loose chain (imagine a slightly sticky freehub) from scratching the stay, not to prevent damage when you 1) drop the chain completely and 2) don't stop.
Two recommendations: If you drop a chain, stop and put it back on by hand. I have seen people sheer off rear derailleurs trying to coax a chain back on. Secondly, to keep it from dropping on the inside, get a "chain watcher". Great gizmo.
--
David L. Johnson
__o | Let's not escape into mathematics. Let's stay with reality. -- _`\(,_ | Michael Crichton (_)/ (_) |
distorm-<< I've ridden it only 50 miles since then, including a ride up and descent down 3800 ft Mt Diablo in the East SF Bay area yesterday. It seems to be OK no sign of failure, but I keep going in my head what somebody told me, "If any carbon fibers show it's [censored]." Any opinions? Should I send it off to Trek now or give it a while and pretend I'm Lance.
By the way, I consider this a Trek defect. That wussy little chain stay protector is stuck on with a glorified scotch tape...not meant to last very long and certainly not fit to take the brunt of a tearing chain. >><BR><BR>
I would not ride the bike down any big, scary decents...send it back for repair..but why warranty? Is chucking the chain off the DA triple somehow a frameset manufacturer's defect? Maybe shimano ought to repair it.
Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302 (303)440-3535 vecchios.comvecchios.comOpen ↗ "Ruote convenzionali costruite eccezionalmente bene"
Two recommendations: If you drop a chain, stop and put it back on by hand. I have seen people sheer off rear derailleurs trying to coax a chain back on. Secondly, to keep it from dropping on the inside, get a "chain watcher". Great gizmo.
I'm having trouble visualizing how the chain can damage the chain stay or shear the rear derailleur just by trying to re-mount it on-the-fly.
Can somebody explain it to me?
Luckily for me, it's rather rare for my chain to come off; so far, I've been able to adjust for it on my bikes.
"David Bailey" <[email hidden]> wrote in message news:<[email hidden]>...
Quoted message said:
There is something like 30 layers of carbon so you should be OK
Wouldn't you feel bad if you were wrong and this guy got hurt or killed? Of course not or you wouldn't make claims about the safety of something you haven't personally seen and analyzed (if you even could which your bald-faced claim makes no support for).
Two recommendations: If you drop a chain, stop and put it back on by hand. I have seen people sheer off rear derailleurs trying to coax a chain back on. Secondly, to keep it from dropping on the inside, get a "chain watcher". Great gizmo.
I'm having trouble visualizing how the chain can damage the chain stay or shear the rear derailleur just by trying to re-mount it on-the-fly.
Well, this guy I was riding with dropped his chain. He was moving along about 15-18mph on the flats at the time, and the chain went off the big ring. He kept turning his cranks, trying to catch the chain by moving the front derailleur inward, when the chain got a kink in it. As he grabbed some of the chain on his chainring and started pulling, the kink travelled back to the jockey wheels. At that point it jammed, but he kept pulling, and the derailleur was pulled around the cassette. Fortunately he had a separate derailleur hanger, so he got that replaced and did not have to get a new frame, but he was done for the day.
--
David L. Johnson
__o | We have a record of conquest, colonization and expansion _`\(,_ | unequalled by any people in the Nineteenth Century. We are not (_)/ (_) | to be curbed now. --Henry Cabot Lodge, 1895
"Java Man (Espressopithecus)" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Quoted message said:
It is worse than that: it is actively misleading. Consider a more rigid rim.
Quoted message said:
But we're discussing bicycle wheels, which have a very flexible rim.
Irrelevant. The relatively large change in tension in the bottom spokes is entirely a function of rim deformation, as far as my reading of the FEA goes, so if you take a more rigid rim, some of the standingness becomes hangingness. IOW, "hang" and "stand" obscure rather than illuminating the issue.
"David Storm" <[email hidden]> wrote in message news:<[email hidden]>...
Quoted message said:
Well, my worst fear occurred with my new Trek 5500. When approaching a steep hill, I shifted the Dura-Ace triple into the small chain ring and it plopped right off on the inside. I quickly shifted up and kept on pedaling to coax the chain back on. This time, however, the chain backed up from the bottom tearing off the metal chain stay protector and scraping the chain stay. What I ended up with is a shallow gouge on the outside of the chain stay just behind the bottom bracket. A few frayed carbon fibers stuck out. I took the bike to LBS where I bought it. They said the damage was iffy, and they would send the frame off to Trek if I wanted for a closer inspection (which they assured me would they would replace under warranty if necessary). Alternatively I could ride it for a while to see how it stood up as it was not clear if there was any structural compromise in the chain stay. I opted for the latter. They glued the metal guard back on and sent me on my way. I've ridden it only 50 miles since then, including a ride up and descent down 3800 ft Mt Diablo in the East SF Bay area yesterday. It seems to be OK no sign of failure, but I keep going in my head what somebody told me, "If any carbon fibers show it's [censored]." Any opinions? Should I send it off to Trek now or give it a while and pretend I'm Lance.
By the way, I consider this a Trek defect. That wussy little chain stay protector is stuck on with a glorified scotch tape...not meant to last very long and certainly not fit to take the brunt of a tearing chain.
I lost my chain on my Trek 5500 Triple within 90 seconds while they were fitting me at the bicycle shop. When I asked about it, they told me that it was actually a defect in the Dura-Ace Triple, and that there is a recall for it: They adjusted the height of the teeth for the smallest chain ring.
Since then I am extremely careful when shifting from my middle to smallest chain ring, but it still comes off anyway. I plan on having them fix it next time it is in the bike shop.
front derailleur inward, when the chain got a kink in it. As he
A kink as in, when it wraps around itself (making a small loop-de-loop), or as in a link that has bent to it's extreme angle and jammed that way?
The first, I'm pretty sure. The chain was bouncing around a lot, and that sort of thing happens.
--
David L. Johnson
__o | What is objectionable, and what is dangerous about extremists is _`\(,_ | not that they are extreme, but that they are intolerant. (_)/ (_) | --Robert F. Kennedy
I lost my chain on my Trek 5500 Triple within 90 seconds while they were fitting me at the bicycle shop. When I asked about it, they told me that it was actually a defect in the Dura-Ace Triple, and that there is a recall for it: They adjusted the height of the teeth for the smallest chain ring.
Since then I am extremely careful when shifting from my middle to smallest chain ring, but it still comes off anyway. I plan on having them fix it next time it is in the bike shop.
Cheers,
Alex
Yes, I've heard something about the Dura-Ace triple giving problems but nothing specific. This thing is a real pain. Not only does it constantly drop off small chain ring, but it tends to skip the middle ring going in either direction. I've had it in to my LBS twice to get it fixed, but it continues to jump off the small ring. I grit my teeth every time I have to shift up front. Sounds like a recall might in order.
Since then I am extremely careful when shifting from my middle to smallest chain ring, but it still comes off anyway. I plan on having them fix it next time it is in the bike shop.
You may be able to, very simply, adjust the L screw on the front derailleur.
Or you could let them do it for you and save you the trouble. 🙂
[email hidden] (Qui si parla Campagnolo) wrote in message news:<[email hidden]>...
Quoted message said:
distorm-<< I've ridden it only 50 miles since then, including a ride up and descent down 3800 ft Mt Diablo in the East SF Bay area yesterday. It seems to be OK no sign of failure, but I keep going in my head what somebody told me, "If any carbon fibers show it's [censored]." Any opinions? Should I send it off to Trek now or give it a while and pretend I'm Lance.
By the way, I consider this a Trek defect. That wussy little chain stay protector is stuck on with a glorified scotch tape...not meant to last very long and certainly not fit to take the brunt of a tearing chain. >><BR><BR>
I would not ride the bike down any big, scary decents...send it back for repair..but why warranty? Is chucking the chain off the DA triple somehow a frameset manufacturer's defect? Maybe shimano ought to repair it.
Seems to me that if he bought a complete Trek bicycle, then it is Trek's responsibility for building in a defective shifting mechanism; if he bought a frame and parts and got the bike assembled then it's the bike shop that did the assembly; if he bought a frame and built it himself then it's his own problem, unless it is a verifiable Shimano defect, in which case it's their responsibility but good luck on collecting.
