Just made one of my bikes singlespeed and not happy with the current chain tensioner. It's just a cheap one that attaches to the derailleur hanger with a single jocky wheel. It's noisy due to the small jockey wheel.
What else might work better?
Eccentric BB if you can get one to fit
Will an eccentric bb fit with DUB cranks and threaded BB.
Should do IF you can find a bsa version
Unsure if NINER do a bsa one off top of my head though may well be worth searching 👍
Can you use a half link chain to help with chain length/tension? Or are they just for BMX and Jump bikes nowadays.
Has the frame got ISCG tabs? If so, a bash guard with a bottom roller can be used and is much neater than a rear mech style tensioner.
Best tensioner I ever had was a Paul Components Melvin - just had a look on eBay and bloody hell - they have seriously gone up in price!!! They do work really well though.
Alfibe.
Not the lightest or neatest but they do just work.
Got one on my race bike and one on my commuter
I've used in the past, an SA version which is very similar in design to the Melvin. Twin jockey wheel arrangement.
Bit cheaper too!
I'm restricted to a derailleur hanger tensioner unless I can find an EBB that would take a DUB BB.
I’m restricted to a derailleur hanger tensioner
You can use a BB mounted Stinger device no problems with a threaded BB.
Or even a BB mounted ISCG adaptor and chain device.
Surly Singleator here. Bit pricey but chain has only come off once in 18 months of use. I’ve used EBB and horizontal drop outs in the past but found them a PITA. Not such a clean look but it’s on an old 26” frame so don’t care what it looks like!
+1 for a Surly Singleator too. Got it on the commuter and it’s been faultless.
I find the Singular a bit annoying, I have to remove the QR skewer completely to get the wheel out
Not such a problem if you have bolt thrus, obvs
I've tried a few and the best by a long shot was a stinger style one. I used a decent jockey wheel rather than the roller.
It's quiet, doesn't need too much tension to keep the chain on due to increased chain wrap.
Just needs protection on the chainstay as the chain runs closely.
The mech style ones I've tried have always been a pita for one reason or another and tend to feel draggy to me due to the tension needed.
Rohloff chain tensioner is excellent. Or a Paul Melvin which is really just a rear derailleur that doesn’t move.
https://www.sjscycles.co.uk/hub-spares/rohloff-chain-tensioner-8250/
How do you tighten an ISCG roller? I thought about it before but realised you need to take the cranks off to tighten the screws. Or do you just mark it relative to a spot and then make sure it's on target before tightening?
How do you tighten an ISCG roller?
It doesn't need to be that accurate. You can normally get 90% of the way there with a good eying up.
Sometimes you can get to the bolts through the chainring with a round head hex key and rotating the crank.
If not just tighten the bolts to about 75% then tap the stinger round for the final adjustment.
There's no tension on the bottom of the chain so pedaling won't move it.
There’s no tension on the bottom of the chain so pedaling won’t move it.
Huh, neither there is.
Interesting...
Stinger type here too, it's easy, clean and makes dropping the back wheel out a POP (handy if you have a few sets of wheels for the same bike)-
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You can get to the ISGC bolts through the ring with an allen key.
Another vote for the Rohloff chain tensioner. I’ve been using one on my SS Scandal for a couple of years and it’s worked fine.
I'm using a BB mount Stinger on my bike & have a iscg mount one in my spares box, could do with finding an iscg BB mount converter thing, used to get them free with some Superstar chain guides but they seem super expensive now.
@thepodge Is it just a thing that goes behind a threaded BB that has ISCG mounts on it that you need?
Stinger type here too, it’s easy, clean and makes dropping the back wheel out a POP (handy if you have a few sets of wheels for the same bike)-
You can get to the ISGC bolts through the ring with an allen key
Definitely the best solution to vertical dropouts.
@kayla1 yeah that spacer thing with tabs, just looked through my for sale stuff and I clearly had two that I sold for about a fiver but that was when I had bikes with welded on mounts.
I'm running a separate top guide & bottom roller on my Alfine commuter, wondering if a combined one would be better but can't try without iscg.
Have you worked out a magic ratio? There used to be a few online calcs which worked off of the chainstay length. You could also try using a ghost gear, basically a sprocket in-between the chain to tension.
Example of a ghost gear
Have you worked out a magic ratio?
At the moment it has a 34/18 with a 27.5 wheel. Playing about with the chain it might work with a 33t chainring but they look a little rare.
If not I think I'll try a stinger style tensioner mounted to the bb.
Edit. Just seen an ISCG adapter for £9.99 so that's opened up a few more options.
Best bolt on tensioner I ever used was an old short cage LX rear mech but with a rubber MRP chain device roller instead of the bottom jockey wheel (and no top jockey wheel, just the bolt, chain went straight from sprocket to bottom roller).
I don't think I ever dropped a chain, reasonably quiet, robust. Would work equally well with an old short cage road mech.
If I go for a stinger tensioner I could get a BB mounted one or an ISCG adapter which looks like it might be easier to adjust. I see there is ISCG and ISCG05. Other than one being larger is there any other benefit?
I adjust my bb mount one with the gentle tap of my biggest hammer. Worked fine so far, all you're doing is rotating a spacer.
I think the Stinger has slots so it'll run ISCG and ISCG05. 05 is the slightly newer standard but other than that its all basically the same.
Other than one being larger is there any other benefit?
If you have tabs then only one or the other will fit. If you don't have tabs and will be running an adapter then it doesn't make a difference. If you're running an adapter, check if it's 1.5mm or 3mm thick, the latter only work with 68mm BB's.
-05 standardized the angle of the tabs which meant fewer cases of guides clashing with chain stays or having to be installed at inefficient angles. Obviously with an adapter you can install it at any angle.
Ah I see. The BB is 73mm so no spacers between the BB cups and frame, but there is a plastic spacer between the drive side BB cup and crank.
edit, I meant 2.5 or 5mm thick.
Is that a DUB system? Basically the adapter has to sit on the threaded part of the BB sandwiched against the frame, so you'd have to check your crank's instructions as to how that's dealt with.
Yeah DUB. The plastic spacer is 2.5mm so I guess replaces that.
Could you wrap the tensioner wheel in a slice of road inner tube?
I've used a Surly singleator and they're good! not as good as the Rohloff but a lot simpler...
Could you wrap the tensioner wheel in a slice of road inner tube?
What for?
Before I give up, could anyone help me find a Stinger style device that's in stock with a reasonable delivery date . Either BB mounted or ISCG with an adapter. And needs to be no more than 2.5mm thick.
All I've found so for are some that include a bash guard and top guide but I'd end up cutting them off which seems a waste. And some on amazon but the delivery date is too far away. The only one that was available didn't specify if it was ISCG or ISCG05 and I ca only get an adapter with ISCG.
https://www.superstarcomponents.com/en/duo-dual-ring-guide.htm
Comes with adapter, just unbolt the bash plate, you're stuck with tabs but not the end of the world.
The adapter looks thicker than 2.5mm.
Best one I ever had was magic ratio. 😎
I'm running a magic ratio right now on my commuter, stumbled across it by accident. Best thing ever!!
I've got a Rolhoff tensioner I'll prob be advertising shortly, not sure I ever used it -- drop me a message if you're interested
Tried to find a magic ratio but no luck. I've got a 34/18 and still need a tensioner. Not got any other chainrings etc to try out.
Might be thicker than 2.5 but I doubt 1mm here or there is going to make much difference is it? I'm running top & bottom guides separately, both rammed in behind the bb on my Alfine setup, I've no idea what spacers there should be or what thickness or what chainline I should be running but it's all working fine.
If you're concerned, just get a rear mech mount one.
@mjsmke, do you know your chainstay length? If so you can use this calculator to work out the magic ratio
Might be thicker than 2.5 but I doubt 1mm here or there is going to make much difference is it?
I have a 2.5mm spacer and the preloaded the non drive side is only wound in half a turn. It won't accommodate an extra 1mm. Unless I file something down, but don't really want to do that.
https://eehouse.org/fixin/formfmuI saw that last week and had a play around. It's pretty good but still could find anything that worked. It said a 34/18 would be perfect but it's too loose, even with a half link. 34/19 was close but not perfect enough without a tensioner. 34/20 works but too low.
I've ordered a cheap Zitto one of Amazon so will see how that goes.
Just measured the thickness of the adapter kindly sent by @Kayla1 which looks like the ones I got from Superstar as part of a whole guard and its a shade under 2.5mm.
Thanks. I bought a Zitto chain device off amazon. Its basically a stinger but with a small jockey wheel and a top guid too. I cut the top guid off and replaced the jockey wheel with a better quality one. Only done 1 ride on it but it works well and is very quiet. Much quieter than my old derailleur hanger tensioner.
