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Recreational Cyclocross and Gravelbiking This has to be the most physically intense sport ever invented. It's high speed bicycle racing on a short off road course or riding the off pavement rides on gravel like :The Dirty Kanza". We also have a dedicated Racing forum for the Cyclocross Hard Core Racers.

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Old 09-16-07, 07:04 AM   #1
PdxGecko
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Dropping the Chain

We had a dirt road crit yesterday, I was doing well leading the second pack of riders when twice in the last lap I dropped my chain to the inside. I'm new to cross and was wondering if it was an error in my techinique that led to the dropped chain. I have an outsidechain guard and am running a single chainring.
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Old 09-16-07, 07:33 AM   #2
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Double guard rings or at the least a "chain keeper" "dog fang" or other gadget on the inside. Kinda compromises the simplicity, elegance and light weight of the single ring, but it do work.
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Old 09-16-07, 08:10 AM   #3
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Dropped Chain

I do have a chain watcher. I'm going to switch to a Jump stop chain guard and also take a link or two out of the chain. (The bike was set-upby a road mechanic.) I was just wondering if there was something I did that would have caused the chain to jump. Since it was the last lap, I figured my fatigue has caused some error, such as sifting to too low a gear.
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Old 09-16-07, 09:15 AM   #4
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I don't think it's anything you did in particular. You probably just hit the right kind of bump. If your not switching rings in the front then it's nothing you did. Did the chain go under the chain watcher or something? If so you probably don't have it set up right or it was just a bad situation. The jump start is better imo.
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Old 09-19-07, 08:15 PM   #5
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if you can shift it back on, no foul
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Old 09-20-07, 06:32 AM   #6
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Chain jump

Since it's a single front chain ring, no front derailleur.

The question is really, Is there a pedalling or shifting or gearing technique that reduces the chance of the chain jumping off the chainring?
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Old 09-20-07, 08:28 AM   #7
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Quote:
Originally Posted by PdxGecko View Post
Since it's a single front chain ring, no front derailleur.

The question is really, Is there a pedalling or shifting or gearing technique that reduces the chance of the chain jumping off the chainring?
not in CX. add a front derailleur and set the screws and use it as a chain keeper

or use a DH mtb chain keeping system, with rollers. It'll never come off with that
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Old 09-20-07, 09:09 AM   #8
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Originally Posted by PdxGecko View Post
The question is really, Is there a pedalling or shifting or gearing technique that reduces the chance of the chain jumping off the chainring?
I assume you threw the chain while coasting over bumps? You're less likely to throw the chain while pedaling, but you can't always pedal.
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Old 09-20-07, 09:18 AM   #9
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, no front derailleur.
Yeah, put that back on. It helps keep the chain on.
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Old 09-20-07, 10:59 AM   #10
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Originally Posted by PdxGecko View Post
We had a dirt road crit yesterday, I was doing well leading the second pack of riders when twice in the last lap I dropped my chain to the inside. I'm new to cross and was wondering if it was an error in my techinique that led to the dropped chain. I have an outsidechain guard and am running a single chainring.
Dude, you dropped your chain twice on a lap at Kruger's? Running a single ring? I have no idea how that could happen. You must have been in your smallest cogs the whole time (far outside) so that's going to put the most slack into the chain but still! Shift into your smallest cog and check the chain tension -- it must be hanging slack. The shift into the biggest and pinch some links together to figure out how many you can remove.

I'd guess the scenario is that you have way too much slack in your chain. You were in one of the two smallest cogs since you are running single and that was a flat course. You set up for a corner and spun the crank backward to put the outside pedal down while going over light chop. That backward spin and light bumping put the chain off.

If your chain came of at Kruger's, you will have a nightmare at any real cross race.

Really, you should be able to fix this. If the chain length seems right, you might have an issue with dérailleur spring tension. If you just can't figure it out, head over to Sellwood Cycle Repair and get those guys to help you out. Don't listen to the other advice given in this thread so far ...
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Old 09-20-07, 10:19 PM   #11
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Krugers Kermesse

The first drop was in the rutted section after the first right past the start. The second drop was on the last turn before the finishing straight. I was coasting both times. I do think that I probably need to check the chain length. I'm also changing my inside chain guard.

I was thinking that being in a smaller gear would allow more chain slack and "bouncing". I'll check my chain length this weekend.

No Hood River X for me, unfortunately it's my 21st anniversary & doing a Cross race is not what my wife has in mind for us! I would really like to go to Starcrossed, but Redmond is even further.
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Old 09-21-07, 11:41 AM   #12
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There's nothing inherently unreliable about a single-ring set-up.

I also run a single-ring on my cross bike, but I've never once dropped a chain, not even after a crash. My bike is set up with a single-speed 42t chainring, an outer chain guard, an inner "Chainwatcher", and I'm using an old short-cage DA rear derailleur, which provides a lot of spring tension. I suspect the tension in the derailleur and the minimal chain length has a lot to do with the reliability of this system.
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