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DMRSTS Chain Tensioner
4.6
0 available in-store, 173 available online
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- Simple Tension Seeker (STS) allows the use of a 1 speed drivetrain on a vertical drop frame
- Stainless steel arm mounts to derailleur hanger and dropout
- Loosen bolt and swing down and back to adjust chain tension
- High density urethane pulley with sealed cartridge bearings
MPN
DMR-TENS-SIMP-TWN
Tree Fort ID:
333222338236
Review Summary
LIKES
Construction (2),
Price (7),
Installation (2),
Quiet (1),
Size Options (1)
WORKS FOR
no tags yet
DISLIKES
none
4.6 GEARS
9 reviews
9 reviews
Customer Questions
Q.
asked by: a guest
It will not keep the chain taut. I tighten both screws down pretty hard and after a few cranks, the chain is loose again. The bike is a late model Marin Wolf Ridge with Vertical drop-outs which I converted to a single speed. Wondering if I need to take a few more links off the chain?
It will not keep the chain taut. I tighten both screws down pretty hard and after a few cranks, the chain is loose again. The bike is a late model Marin Wolf Ridge with Vertical drop-outs which I converted to a single speed. Wondering if I need to take a few more links off the chain?
A.
anwered by: canteau
The DMR STS Chain Tensioner like most chain tensioners of this style are designed to take up the slack in the chain of a link or two. If you are running the chain at the full length that is was geared the chain is going to be way too long.
The DMR STS Chain Tensioner like most chain tensioners of this style are designed to take up the slack in the chain of a link or two. If you are running the chain at the full length that is was geared the chain is going to be way too long.
Q.
asked by: a guest
Can you adjust the chain line on this tensioner? It looks like it's fixed...
Can you adjust the chain line on this tensioner? It looks like it's fixed...
A.
anwered by: a guest
The wheel can slide on the axle, no need to change parts
The wheel can slide on the axle, no need to change parts
A.
anwered by: a guest
Yes you can. Simply replace the spacer next to the pulley with individual washers (from the hardware store) and it gives you some flexibility.
Yes you can. Simply replace the spacer next to the pulley with individual washers (from the hardware store) and it gives you some flexibility.
Q.
asked by: a guest
will this work if i have 12x142mm thru axle at the back tire?
will this work if i have 12x142mm thru axle at the back tire?
A.
anwered by: a guest
No. This tensioner uses the derailleur hanger for the adjustment, but it pivots on the black part in the picture that mounts under the head of the skewer. it will not work with a through axle at all.
No. This tensioner uses the derailleur hanger for the adjustment, but it pivots on the black part in the picture that mounts under the head of the skewer. it will not work with a through axle at all.
Q.
asked by: a guest
Converted older road bike frame to a single speed. Will it work with the derailleur hanger
Converted older road bike frame to a single speed. Will it work with the derailleur hanger
A.
anwered by: mlewis
Yes, this is designed for just that application.
Yes, this is designed for just that application.
Q.
asked by: a guest
Having problems with it coming up how can I fix it?
Having problems with it coming up how can I fix it?
A.
anwered by: mlewis
For technical help, feel free to give us a call, or you can contact DMR directly through their web site at www.dmrbikes.com/contact/
For technical help, feel free to give us a call, or you can contact DMR directly through their web site at www.dmrbikes.com/contact/
Q.
asked by: a guest
Can it be mounted to push up on the chain instead of down?
Can it be mounted to push up on the chain instead of down?
A.
anwered by: canteau
It will depend on the chainstay clearance of the frame.
It will depend on the chainstay clearance of the frame.
Customer Reviews
5
August 07, 2013
reviewed by: turbotodd
very happy with this tensioner. it's much easier to set up and adjust than the Surly Singleator I had previously. I'm a bit of a weight weenie and the STS is a little heavy, but well worth it since my chain actually stays on now.
solid construction, well designed. nice big replaceable pulley bearings, polyurethane pulley wheel is heavy duty and very quiet. pulley floats side to side with your chain, so it's always in line.
Its two-bolt design makes it easy to finely adjust chain tension.
two notes:
1. the groove in the pulley is NOT wide enough for 1/8" BMX chains, which is what I'm using on my single speed. I used a Dremel to widen the groove, no issues since.
2. only works with standard quick release, not thru axles.
vote
vote5
December 12, 2011
reviewed by: alan29er
Purchased this to replace the poor quality spring tensioner that came with a singlespeed kit sold via another huge online bicycle retailer. The DMR piece looks great and appears to be pretty high quality. Only had it installed for a week or so now but it has been working flawlessly. I can't imagine any issues down the road. Looks like a stout piece that will provide years of trouble free service.
5
January 04, 2013
reviewed by: A Guest
This tensioner is simple and works extremely well. The floating roller on the tensioner allows for some minor lateral sway in the chain, but be aware that the success of any singlespeed conversion will be based more on a straight chainline and drivetrain (no bent chainrings or wobbly hubs) and a stiff frame. Without that, anything less than a rear derailleur will struggle. Also, using singlespeed specific chainrings and cogs help, as they have longer teeth that are not ramped for shifting so they hold the chain better.
I used this tensioner on a K2 Zed 4.0 hardtail and it worked great. I did run into an issue with a half-link in the chain I was using having a pin that stuck out slightly further than the rest of the link. It would periodically catch on the roller of the tensioner, and ride up over it, which would bend the tensioner out of place. Once I figured it out, I ground down the protruding pin on the chain and no more issues. I suppose you could also round off the channel on the roller to address this issue, but to me it made more sense to fix the chain.
5
September 10, 2017
reviewed by: Ron Almeida
This is the first chain tensioner I've ever bought or installed. I like it so far, it seems well made. I had two issues with installation:
1- I had to file 2 or 3 mm from the black aluminum bit that is attached to the quick release skewer. Part of it sits in the dropout slot below the axle, and was a bit thicker than my dropout. Before modifying the aluminum piece the quick release could not engage the dropout. Not hard to fix if you have a vice and a file. (BTW the bike is an early '90s steel mtb from a good brand with forged dropouts.)
2- There was no room for the quick release spring on the drive side once the tensioner was installed. No big deal, but it took several tries switching the spring from outside to inside before I realized I hadn't put it together wrong.
3- This could have been easier with instructions. None in the package or online.
5
March 15, 2013
reviewed by: A Guest
Hands down, the best tensioner option for vertical dropouts I've ever used, and I've used them all. When installed properly operation is whisper quiet and feels like it's welded to the frame. Use it in the push down mode, allows for much more flexible chain ring/sproket combinations.
5
September 03, 2012
reviewed by: A Guest
I use this on my CX bike. I use it to push up on the chain, towards the cog. Works great with a straight chain line and singlespeed cogs, and singlespeed chain.
5
December 12, 2011
reviewed by: alan29er
Purchased this to replace the poor quality spring tensioner that came with a singlespeed kit sold via another huge online bicycle retailer. The DMR piece looks great and appears to be pretty high quality. Only had it installed for a week or so now but it has been working flawlessly. I can't imagine any issues down the road. Looks like a stout piece that will provide years of trouble free service.
2
September 28, 2010
reviewed by: koingames
I rocked this for about 3-4 months, of daily use on jumps, trails, etc. I have an aluminum frame, with an older drive system that is not perfectly smooth any more. Basically any movement in the chain ring, or chain tension rather, will put a lot of force on the weak threads of the parts that screw together to hold it in a taught position. Thus, you end up kicking it with your foot every five minutes so your chain doesn't pop off. Granted if you have a steel frame, or stiffer framed bike that doesn't flex much, and a good smooth drive system, as well as don't ride super hard like I do, then this will probably work fine. It worked great the first month, but I highly recommend a spring loaded tensioner that can go with the flow and keep your chain tight in any situation.
4
May 27, 2010
reviewed by: A Guest
This STS tensioner installed quick and easy, and is quickly adjusted to fit the tension needed. The only issue I ran into was fine tuning the chain line. I installed the tensioner on a 2008 Specialized rockhopper frame that has a 50mm chain line. I ended up having to put my front chain ring in the third chain ring position in order to get a good line. Overall, well worth the purchase and time to fine tune. I couldn't be happier with the result.
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