# DMR STS tensioner?



## sean salach (Sep 15, 2007)

I read the reviews, but want more. I tried the search function, but mtbr's internal search engine seems to ignore 3 letter 'words'.

Anyone using it? pros/cons? I am soon to find myself using a bike with vert dropouts, that doesn't look like it will work very well with a magic gear. It's a loaner, so I don't want to spend a ton of money on a FC bb or $50 on a tensioner. 

The STS looks relatively simple, but maybe noisy. I wonder if I could retrofit a der jocky wheel to it....


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## boomn (Jul 6, 2007)

I used a copy of that from a different brand before I got my SS frame. My particular one might not have been exactly the same, but it was limited in how much slack it could take up in push-up mode. The angle and length of the actual STS might be better for this, but I don't know.

Also, mine was a little noisy at times but only because of another weakness: a slightly tweaked hanger would cause the chain to walk over to one side of the roller and rub against the side of the channel on the roller. Thankfully I notice noise less while I'm pedaling and struggling and tensioners don't make any noise while coasting


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## sean salach (Sep 15, 2007)

My preferred gear is within .2" of chainstay length to a magic gear on this bike, with a half link. I would like to have it nice and snug though. So, somewhat limited throw shouldn't be too much of an issue. The roller on the DMR looks like there's not much room for the chain to walk, so that issue should be good.

Here's a link in case anyone is wondering what I'm talking about:

https://www.dmrbikes.com/?Section=p...ory=3&CategoryName=Chain Devices&itemid=CDSTS


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## sin3kal (Feb 17, 2008)

Only issue I had with mine was that the roller groove was not wide enough for singlespeed chains. The widest it would accept was an 8 spd chain. Also ran into the problem with certain cog configurations and the tensioner arm hitting the chainstay before properly tensioning whey used in the push up mode. The bolt that goes through the der. hanger was also kind of soft. Recommend NOT using ball end hex when tightening. Other than that it is my favorite tensioner of those currently available and is very affordable.


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## MMcG (Jul 7, 2003)

What about a Rennen Rollenlager or are those no longer available?


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## sean salach (Sep 15, 2007)

$21.95
http://www.jensonusa.com/store/product/CH409Z16-Dmr+Sts+Single-Speed+Chain+Tensioner.aspx

vs

$46.98
http://www.pricepoint.com/detail/15...-Rollenlager-Single-Speed-Chain-Tensioner.htm


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## MMcG (Jul 7, 2003)

ahhh- yeah I realized that after I made teh suggestion. Would a Blackspire Stinger get the job done? Does the tension need to be at the dropout or can it be up closer to the chainrings?


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## MMcG (Jul 7, 2003)

ahhh- yeah I realized that after I made teh suggestion. Would a Blackspire Stinger get the job done? Does the tension need to be at the dropout or can it be up closer to the chainrings?


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## boomn (Jul 6, 2007)

MMcG said:


> ahhh- yeah I realized that after I made teh suggestion. Would a Blackspire Stinger get the job done? Does the tension need to be at the dropout or can it be up closer to the chainrings?


tension can be set up front with the right setup (see the Yess ETR-B), but I really don't think a Stinger would do it well. You would have to loosen the BB cup or BB cartridge to rotate the Stinger, which is hard to do with the crank installed for many setups


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## sean salach (Sep 15, 2007)

Too late anyway, I went ahead and ordered the DMR. Thanks for the help!


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## Velobike (Jun 23, 2007)

I have one. Was for a temporary ss conversion. Prefer it to the Surly style. Works perfectly fine and can be straightened if you bash it.


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## hopper25 (Aug 23, 2007)

You can fit a derailleur jockey wheel on the shaft, so that it floats freely side to side. I have a commuter setup like this and it's fine for that purpose. 

Tried it on my Niner though and the chain kept jumping off the jockey wheel when going over rough ground. So may not work all that well off road.


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## fishcreek (Apr 10, 2007)

boomn said:


> You would have to loosen the BB cup or BB cartridge to rotate the Stinger, which is hard to do with the crank installed for many setups


if you use an ISCG adapter, you don't have to loosen the BB. but the amount you will be spending on adapter and stinger, might as well go for the yess.


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## eman2 (May 3, 2004)

*I have one and it works*

I had one on my cannondale. It worked well. I found it was a little noisy when back pedaling but going forward it was pretty smooth. The roller is on a bearing riding on a shaft that allows some side to side float for chainline adjustment. No spring to worry about like the surley. I replaced mine with a ENO eccentric hub which is nice but quite a bit more coin. I had my DMR STS for sale in the classifieds a bit ago but no one wanted it. Maybe people don't know much about it - its a great cheap way to try out SS for cheap.


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## Dwad (Apr 26, 2008)

*I've got one*



sean salach said:


> I read the reviews, but want more. I tried the search function, but mtbr's internal search engine seems to ignore 3 letter 'words'.
> 
> Anyone using it? pros/cons? I am soon to find myself using a bike with vert dropouts, that doesn't look like it will work very well with a magic gear. It's a loaner, so I don't want to spend a ton of money on a FC bb or $50 on a tensioner.
> 
> The STS looks relatively simple, but maybe noisy. I wonder if I could retrofit a der jocky wheel to it....


Works great. 8 speed chains fit in it fine, get it or the Rennen, the push up tension method is the best for low budget SS solutions.

Aesthetically chain tensioners are not so nice & the DMR with it's orange pulley adds to the blight factor.


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## MichaelW (Jul 10, 2006)

I used the STS tensionor for a while, and it works great. There is a small amount of nosie, or there was with mine, but not that noticeable if you are riding off road. I used mine for both SS road & off-road, it handled both great.


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## half_squid (Sep 20, 2008)

The DMR STS is my favorite chain tensioner for single speeding a bike with vertical dropouts. You adjust the chain tension after the wheel Q/R is tightened, unlike the Rennen, which has you loosen the Q/R, and then adjust the tension and tighten everything back up. Unlike the Rennen, you have to use a Q/R axle with the DMR. The ones I've had I had to space the shaft for the roller further inboard with washers to match the chainline. I'm running a wider roller--I think its an MRP--on one that makes it quieter and lets you use a 1/8" chain if you are so inclined. I use mine in the push up style and they work perfectly; however, I try to start with a gearing combination that is pretty close to a "magic gear" so they don't have much slack to take up. Measure your chainstay and play with an online magic gear calculator to try to figure out what combinations might work well for you.


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## forkboy (Apr 20, 2004)

I'd leave it as is. It's actually very quiet - much quieter than a jockey tensioner.

Only problem is that the black part doesn't fit in all dropouts. I had to open mine up a bit. And you need to carry a 5mm hex in case of tire changes. Other than that, it's great.


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## sean salach (Sep 15, 2007)

Good stuff. You guys are increasing my confidence in my purchase, and I can't wait for it to get here. 

Forkboy, would it not have been cheaper(if something got messed up)/easier to file some material off of the black part of the tensioner than to spread your dropout?

Good news about noise. I'll be running an 8sp chain, so the stock roller should work fine for me.


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## forkboy (Apr 20, 2004)

sean salach said:


> Good stuff. You guys are increasing my confidence in my purchase, and I can't wait for it to get here.
> 
> Forkboy, would it not have been cheaper(if something got messed up)/easier to file some material off of the black part of the tensioner than to spread your dropout?
> 
> Good news about noise. I'll be running an 8sp chain, so the stock roller should work fine for me.


I didn't really "spread" the dropout - more just sanded down the front-side corner and a little material off the der. hanger so the black thing would slide in. Where the dropout holds the axle is still the same - the mouth is just a little wider..

They were Ritchey dropouts. Anything else will probably be fine... they are just slightly curved instead of straight.

I did some work to the black spacer too. It wasn't possible to do all the work necessary on the spacer and still have it fit correctly when fully seated.

You'll be stoked. I moved to WI ecc hubs, and now my DMT is entering it's 2nd life on my girlfriend's Dean YBB-SS.

Here's the pic... Not too much surgery.


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## sean salach (Sep 15, 2007)

I've got a few hundred miles on this tensioner now and am really happy with the purchase. It performs as all the above reviews stated. Quiet, simple, secure. I only heard it when backpedaling on smoother trail. No noticeable resistance. Low profile and out of the way. Good stuff.


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## bad mechanic (Jun 21, 2006)

I'm late to the party, but I used one on my first SS, and it's now doing duty on my friend's first SS. It's an excellent tensioner, and I have no idea why someone would run something with a spring over one of these. Once you install it and adjust tension, you can simply forget about it.


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## _daemon_ (Sep 16, 2007)

I have it on my 29er On One Scandal and I love it, works quite well cannot see how a device like this can work better.


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## wv_bob (Sep 12, 2005)

sin3kal said:


> The bolt that goes through the der. hanger was also kind of soft. Recommend NOT using ball end hex when tightening.


I had the same problem with an older spring-loaded STS. The hex stripped round, so now it's on to stay unless I Dremel it off.


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## EZuphill (Nov 21, 2011)

I know it's an old thread but I have read through and someone said that a as chain does not fit the roller.

Is that still true? Can I use a 10 speed chain? A doublespeak chain?


Sent from my DROID BIONIC using Tapatalk 2


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## bad mechanic (Jun 21, 2006)

The DMR STS fits any multi-speed chain. If you're running a half link, 1/8", or some single speed chains then you'll need to widen the groove on the roller which is easily done with a Dremel.


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## 4SEVEN3 (Aug 12, 2007)

I used a DMR for years with a 9spd chain and never had a issue in the pull down configuration. Excellent product at a reasonable price.


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## eman2 (May 3, 2004)

I used one for years on an old cannondale with a 9 speed chain. It works well in the push up position. A little more drag than a pure ss, but it cheap. I have since changed bikes so mine is just sitting in the parts bin.


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