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Discussion Starter · #1 ·
I went out for a ride today and early on I noticed a slipping/grinding sound and sensation I'd find most comparable to shifting on the cassette under high toque. This would happen when I wasn't shifting, didn't involve the chain switching gears but did seem to happen under heavy load: hard pedaling uphill. While it's happening the wheel also loses power. I got off and walked the bike for a moment about half way around my usual loop and noticed that the cranks were rotating with the wheels while moving forward (rather than in reverse).

Finally, on my way back home riding up a hill the rear wheel seemed to stop working and I was just spinning the cranks with the cassette spinning and making that grinding sound. I actually looked down and I'm pretty sure the gears were spinning (as opposed to the chain slipping around them).

Any ideas? The bike is less than a year old with less than 1,000 miles.
 

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Discussion Starter · #3 ·
Sorry, should have included that. Bontrager sealed cartridge bearing 142x12 rear hub with a Shimano drivetrain - cassette is Shimano HG62. Does that help?
 

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RAKC
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Blown freehub. Either cracked body or pawls are broke. Less than a yr, head to trek lbs and get it warrantied. Shimano aluminum freehubs are known for splitting out. 1k miles is pretty good considering the stories I've read here.

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Yeah!
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Shimano aluminum hubs are for 150Lb triathletes. I have no idea why they use those hubs on any other type of bike. Bike makers can be asses, I guess.
 

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Discussion Starter · #6 ·
Thanks guys - that's really disappointing, but I'm glad it's under warranty. I rode my last bike for 11 or so years, not as hard as this one, but it was original bone-stock and running fine mechanically when I broke it down for a rebuild last year. Hopefully the rest of my new bike endures me a little better, lol.
 

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Discussion Starter · #7 ·
LBS just had a look at it and called me - the pawls were dirty and a little ground up. They need to be replaced, but are apparently not covered under the warranty, somehow. He referred to it as a wear item. If I went with a higher quality hub would I be better off? Are there hubs than can take both 10 and 11 cog cassettes?
 

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RAKC
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Part of that is u r supposed to clean and relube them every so often. Have to look up how without disassembling it or locate/make a tool (I made one) to service them. Read up on the trek website for warranty cause last I read bikes had "bumper to bumper" type warranty for at least one year.

Beyond that, see how much a new freehub body is for it and which ones will fit (not sure which Shimano spec the bontrager labeled hubs use or how that exactly works there).

There are several great hubs out there if u got the cash. Not sure the exact spec and hub style of ur bike, but I run a Shimano m529 hub. Not best engagement but I ride xc so not a problem for me, and at 285 down to 265lbs I am now, its the first freehub that's lasted more than 3 months, going on a year still like new. But I stripped down, clean, regrease with marine grease twice as of 3 weeks ago. First time was a week after buying wheels as I did some creek crossings and wanted to play it safe.

Cheapest option if they won't warranty (and fight it if u can) will probably be a free hub body. Just be sure to take care of it, they aren't built like they used to be. Then save some coin for hope,ck,dt Swiss or ??? Hubs.

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The pawls are certainly a wear item - but if they are replaced you should be back to a 'new hub' feeling.
You can replace the hub if you want, but maintenance is needed on all hubs. You might find the service interval is shorter for the new hub.
 

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Discussion Starter · #10 · (Edited)
I did clean and grease before the season started, but maybe I just ended up washing crap into it (I did my best not to).

The mechanic cleaned out the pawls and said it's good to ride until he gets new ones in. I'll ride those and see how they do for the season, but if they crap out again I'll just upgrade the entire hub.

Thanks for all the advice guys!

Edit: Got the bike back with the cleaned pawls and made it about an 8th into my regular loop; this hub is toast. Will probably just upgrade it rather than wait for them to get new pawls that are just going to fail again anyway.
 
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