# 95% Drive Train
**URL:** https://fixed.org.au/t/95-drive-train/69790
**Category:** Fixed Street
**Created:** [June 10, 2017, 12:27am UTC](https://fixed.org.au/t/95-drive-train/69790 "2017-06-10T00:27:51Z")
**Posts on this page:** 17
**Page:** 1
### Author:  [@Marc](https://fixed.org.au/u/Marc)
#### Post date: [June 10, 2017, 12:27am UTC](https://fixed.org.au/t/95-drive-train/69790/1 "2017-06-10T00:27:51Z")
How do I even explain this. Ok my drive drain runs smoothly in 95% of the cases. Dura Ace in the front Surly playing in the back with a 17T. All driven by a Sram track chain. It sometimes now happens, mostly when riding uphill that there is a certain miss in the game, you can even hear it when you listen closely. You do feel it in the pedals, its like something is loose for a split second or something is not fully engaging. Its really heard to explain but maybe you have/had this as well and know what I’m talking about. Any ideas appreciated. I ride brake less and don’t want my drive train to suddenly fail on me.
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### Author:  [@Lambchop](https://fixed.org.au/u/Lambchop)
#### Post date: [June 10, 2017, 1:17am UTC](https://fixed.org.au/t/95-drive-train/69790/2 "2017-06-10T01:17:57Z")
How’s the chain line/wear - master link catching?
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### Author:  [@Marc](https://fixed.org.au/u/Marc)
#### Post date: [June 10, 2017, 1:30am UTC](https://fixed.org.au/t/95-drive-train/69790/3 "2017-06-10T01:30:18Z")
the chain line is pretty perfect I’d say but the chain ist still the first one when I built up this bike 3 years ago. I don’t ride it that much anymore so its hard to say how many k’s the chain has on it.
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### Author:  [@etomato](https://fixed.org.au/u/etomato)
#### Post date: [June 10, 2017, 2:27am UTC](https://fixed.org.au/t/95-drive-train/69790/4 "2017-06-10T02:27:32Z")
My guesses:
- dodgy sram joiner link
- bent/damaged tooth on chainring or cog
- two chain links seized together
- new bike required
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### Author:  [@manatra](https://fixed.org.au/u/manatra)
#### Post date: [June 10, 2017, 6:15am UTC](https://fixed.org.au/t/95-drive-train/69790/5 "2017-06-10T06:15:32Z")
Cog slipping loose/tight?
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### Author:  [@lokione](https://fixed.org.au/u/lokione)
#### Post date: [June 13, 2017, 7:49pm UTC](https://fixed.org.au/t/95-drive-train/69790/6 "2017-06-13T19:49:57Z")
> [@etomato](#):
>
> My guesses:
>
> - dodgy sram joiner link
> - bent/damaged tooth on chainring or cog
> - two chain links seized together
> - new bike required
What he said, or she. I don’t wish to apply gender stereotypes to Tomatoes.
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### Author:  [@droz](https://fixed.org.au/u/droz)
#### Post date: [June 13, 2017, 8:32pm UTC](https://fixed.org.au/t/95-drive-train/69790/7 "2017-06-13T20:32:50Z")
Check chainring bolts?
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### Author:  [@P\_N20](https://fixed.org.au/u/P_N20)
#### Post date: [June 13, 2017, 9:03pm UTC](https://fixed.org.au/t/95-drive-train/69790/8 "2017-06-13T21:03:41Z")
Is your chain tensioned super tight? Could it be binding when you put the extra load on it going uphill? Will we ever stop answering your question with more questions?
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### Author:  [@lokione](https://fixed.org.au/u/lokione)
#### Post date: [June 13, 2017, 9:44pm UTC](https://fixed.org.au/t/95-drive-train/69790/9 "2017-06-13T21:44:26Z")
Are you using Biopace?
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### Author:  [@Marc](https://fixed.org.au/u/Marc)
#### Post date: [June 15, 2017, 10:14pm UTC](https://fixed.org.au/t/95-drive-train/69790/10 "2017-06-15T22:14:18Z")
It is pretty tight yes…mmmh…everything else looks/seems to be fine. How do I check if a track chain is worn out without having a chain checker tool?
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### Author:  [@P\_N20](https://fixed.org.au/u/P_N20)
#### Post date: [June 15, 2017, 10:17pm UTC](https://fixed.org.au/t/95-drive-train/69790/11 "2017-06-15T22:17:13Z")
^ Ruler. [Google](https://www.google.com.au/?gws_rd=ssl#q=check+chain+wear+with+ruler&spf=1497590126071)
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### Author:  [@LAM](https://fixed.org.au/u/LAM)
#### Post date: [June 15, 2017, 10:26pm UTC](https://fixed.org.au/t/95-drive-train/69790/12 "2017-06-15T22:26:11Z")
Cog slipping is my guess as well. It might be tightening up when going uphill. It’s a weird feeling when it happens,
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### Author:  [@Marc](https://fixed.org.au/u/Marc)
#### Post date: [June 15, 2017, 10:57pm UTC](https://fixed.org.au/t/95-drive-train/69790/13 "2017-06-15T22:57:32Z")
> [@LAM](#):
>
> Cog slipping is my guess as well. It might be tightening up when going uphill. It’s a weird feeling when it happens,
Lets assume its a slipping cog, would this mean I need a new cog or could the flanges at the hub be worn out as well? Meaning I would need a new hub/wheel etc…
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### Author:  [@Cafe\_de\_Keirin](https://fixed.org.au/u/Cafe_de_Keirin)
#### Post date: [June 15, 2017, 11:11pm UTC](https://fixed.org.au/t/95-drive-train/69790/14 "2017-06-15T23:11:53Z")
Oh man… I’m on the edge of my seat every time I get to this thread thinking there will be a resolution. But so far no dice. 😕
On the latest suggestion. Chuck a lockring spanner in your pocket. Wait until the cog ‘slips’ going up a hill. Then get off and see if you can tighten the lockring at all. Might stop it loosening again.
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### Author:  [@PiledHigher](https://fixed.org.au/u/PiledHigher)
#### Post date: [June 15, 2017, 11:33pm UTC](https://fixed.org.au/t/95-drive-train/69790/15 "2017-06-15T23:33:40Z")
> [@Marc](#):
>
> It is pretty tight yes…mmmh…everything else looks/seems to be fine. How do I check if a track chain is worn out without having a chain checker tool?
Calipers
[](https://flic.kr/p/9ZZweH)[Chain Replacement](https://flic.kr/p/9ZZweH) by [PiledHigher](https://www.flickr.com/photos/46435249@N00/), on Flickr
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### Author:  [@LAM](https://fixed.org.au/u/LAM)
#### Post date: [June 16, 2017, 2:59am UTC](https://fixed.org.au/t/95-drive-train/69790/16 "2017-06-16T02:59:02Z")
> [@Marc](#):
>
> Lets assume its a slipping cog, would this mean I need a new cog or could the flanges at the hub be worn out as well? Meaning I would need a new hub/wheel etc…
It depends on how long it’s been like this, and how good your hubs are. Normally if it slips a little you can just stomp up a big hill to make sure it tight, and the tighten up the locking at the top, and it should be ok, but if the hubs are low quality aluminium the thread will be destroyed by now, but you would have noticed it getting worse… The age and wear on the cog is irrelevant to this, it’s all about lockrings and hubs
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### Author:  [@etomato](https://fixed.org.au/u/etomato)
#### Post date: [June 18, 2017, 6:16am UTC](https://fixed.org.au/t/95-drive-train/69790/17 "2017-06-18T06:16:39Z")
Another thing - some cogs can be a fraction thinner than the hub is designed for, meaning that when you tighten the lockring, it bottoms out before it hits the cog. This leaves a tiny gap between the lockring and cog, resulting in slipping each way when you pedal/skid.
I’ve seen this happen with modern hubs that are designed for thicker cogs (e.g. Surly) rather than skinnier ones (vintage Dura Ace)