LBS making excuses?

[Sittingduck]

I think the LBS guy has a point. It's not unusual to wear a chain/cassette out in 1500 miles, using all the gears. If she rides on the smallest cog all the time, then all the wear is concentrated onto one cog. A small cog will wear out quicker than a big one, and middle ring/smallest doesn't give the best chain line, so it's not really surprising if the components didn't last very long.

A chain... maybe (just) but a cassette should be lasting way longer then 1500 miles, IMHO. More like 4000 - 6000 surely?

 

[Peteaud]

Not a good chain line but should have lasted longer.

I would email Trek as they are pretty fussy about their resellers.

 

[Manonabike]

I think the LBS guy has a point. It's not unusual to wear a chain/cassette out in 1500 miles, using all the gears. If she rides on the smallest cog all the time, then all the wear is concentrated onto one cog. A small cog will wear out quicker than a big one, and middle ring/smallest doesn't give the best chain line, so it's not really surprising if the components didn't last very long.

I tend to agree with this comment too.

 

[Inertia]

On a £450 bike, it's steel. On a £5k bike its usually steel/titanium - sometimes alloy or a mix of 3.

Most cassettes are steel - only DA/Record have the mix.

Thanks for the info, good to know

I think the LBS guy has a point. It's not unusual to wear a chain/cassette out in 1500 miles, using all the gears. If she rides on the smallest cog all the time, then all the wear is concentrated onto one cog. A small cog will wear out quicker than a big one, and middle ring/smallest doesn't give the best chain line, so it's not really surprising if the components didn't last very long.

I think the point is true in that you can wear it out by staying in one gear but as she hasn't done that kind of mileage its not the sole reason. Possibly its been set up poorly which has exacerbated the problem and decreased the time it took to go bad.

 

[simon.r]

Not directly related to your question, but 32:11 is a fairly high gear for a novice cyclist, especially if her commute involves hills. If your colleague is new to cycling I wonder if she's grinding along in too high a gear rather than spinning an easier one? It's not uncommon to see new cyclists really straining to push too high a gear when they would, I think, be more comfortable in a lower gear.

It may be worth having a chat with her about this? Just a thought.

 

[actonblue]

Stop debating the quality of components and get your friend to quote the sale of goods act at the LBS and the concept of merchantable quality.That should focus their minds.

 

[I like Skol]

Just read through this thread and didn't spot if anyone asked has the chain seen a spot of oil in it's tortured 400 miles of winter commuting?

I'm not saying the shop are blame free here but an impartial view could be that 400 miles of misuse without any maintenance could easily cause the premature wear of the smallest cassette sprocket in this case?

Still, the shop doesn't come out of this smelling of roses even if they are entirely innocent. I would have thought they would have a re-useable secondhand sprocket kicking around the workshop somewhere and fitting this and some advice to the bike owner about correct gear usage and maintenance routines (sell some lube products here!). Hell, they should be taking the bike in for a 6 week inspection anyway? Most or all bike shops offer this with new bikes don't they?

 

[Inertia]

Thanks for all the replies guys, she has taken it back and they are now going to replace it for free. She was surprised that the guy in the shop basically blamed her and she wanted to know if it WAS her or if he was just blinding her with science. And also of course if it WAS her fault, what she can do to avoid it.

She is the only person who followed my lead as it were and commutes regularly by bike now, she used to have to get lifts, so I try to help as much as I can. I seem to be the expert even though I only have a couple more years of cycling.

AFAIK the only advice was that he said she had damaged it by staying in the one gear (she only switches between two gears). I will advise her to lube the chain more frequently and also to use more of the the gears more often to avoid wearing out one cog excessively.

Oh, I gave you all credit for the help