singlespeed conversion virgin, noob questions !

what bb mounted tensioners would you recommend ?

and also is there any benefit on the wider (more expensive) rear cogs ? can the thinner ones damage the cassette or something ?
 
robadub":mitz0x9u said:
and also is there any benefit on the wider (more expensive) rear cogs ? can the thinner ones damage the cassette or something ?

I specifically chose the Gusset Double Six SS conversion because it has a double width rear sprocket, I heard tales of people having 'narrow' ones digging into the freehub body because of the high load focused in the narrow contact band.

I've seen the Surly Singleater rear tensioner which looks good, and I'm thinking I might even have the option of swapping in my gold jockey from the crap*y Superstar one. http://www.ukbikestore.co.uk/product/80 ... ioner.html I prefer the Black one I think.
 
....the saga continues.

So I posted last night that I liked to look of the Surly Singleater, it can tension up or down. A link to the Surly Website showed the fitting instructions where I noted you need an 18mm cone spanner to assist in fitting it (mental note taken).

This morning I'm thinking maybe I'll strike it lucky and take off the Superstar tensioner to find that I can shorten the chain to perfect length. Like hell I can :( . I can remove one more link repeat then the game is up, oh and the chain is slack as buggery (parden my language).

So I'm looking at the Superstar unit thinking I wonder how far I can chuck it when I see what appears two flats ready and waiting to accept a cone spanner...... hmmmmm.... I wonder.

So an angle grinder and a 16mm cone spanner later I have a 18mm cone spanner in my hand, and I manage to refit the Superstar tensioner 'pretensioned' in a different starting position (ignore the postion of the guidance plate for a moment) allowing it to fit my newly shortened by 1 link chain (previously not possible). Good ho and off we go..... it feels promising, it looks good. I'm peering down at the chain and pedalling gingerly and all is good. Apply more pedal pressure and bang-jump, BO**OCKS :x !!!!!!!

So the chain won't go any shorter even without the tensioner, it won't tension upwards because its so slack that it touches the frame and even when tensioned down it still jumps. What the hell is wrong?

Reminder I'm running a SRAM PC1 1/2"x1/8" SS chain on Gusset Double Six 16T sprocket. That should work together, shouldn't it?

Here's the latest picture of what the tension arrangement looks like.
 

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OK - so if you take the tensioner off, the chain is slack, and you cannot then remove another link, to get more initial tension, as the chain is then too short?

What teeth cog are you running at the front by the way? 32t?

I had similar issues with my Gary Fisher SS conversion, although I'm running 36/16 on mine (as it's mostly used as a commuter). I had the same style tensioner, and found it lacking (the spring inside kept giving-way and losing all tension; bot good!)

Sometimes, there are vertical dropout frames where the maths for SS just doesn't "work" so you cannot get a magic tension by the right number of links and a small amount of chain tension.

This is due to the chainstay length, and if the chain won't run right, even with the tensioner in place, you could look at making a longer chain length by running a slightly bigger front ring (34t as opposed to 32t say) as that - of course - makes for a longer chain.

Also make sure your chainline is correct - with the same-style tensioner as yours, I had chain-skipping as the chainline was just slighty off (by no more, it seemed, than 2-3mm...) but once I got that right, the skipping went away.
 
That frame is no good. I will take it off your hands cheap...

Just joking, but it's a shame there seems to be more faffing about than usual, and spending good money after bad money. I need to ask though, did you actually try a Magic Gear set-up? See my earlier post, you just may well be lucky and be able to ditch the whole tensioner.

A 16T is a relatively small sprocket and it does need sufficient chain wrap, if all these similar style tensioners are just not working think about the "old rear mech" solution like it's being suggested or a Shimano Alfine tensioner and be done with.
 
Do away with the tensioner!!!

I haven't read the whole thread but it seems like your having troubles.

After faffing with several different tensioners that all worked loose in one way or another (the only one that didn't was the Gusset one which was difficult to get the wheel out with!) I found a way round it.

Get a half link chain, they have kinked plates so every segment is both the inner link and outer plates as they below picture indicates.

http://www.bikeradar.com/gear/category/ ... row-31664/

they are available all over the place and as you have that much better chain length options you'll be able to get almost exactly the length you need. I managed it with the 18" Kona Hahanna I single speeded on here and it runs like a dream.

Looks a lot neater as well.

As for the jumping, check both chain line and that where your breaking and closing the chain you don't have a stiff link. I had a differently branded version of the tensioner in your images and a stiff link that when it went through wouldn't bend for the tensioner so it lifted and jumped. never could figure out the exact mechanics of why it happened but sorting the link sorted it for a while until everything worked loose and floppy.

So my set up is as can be seen in this thread and good luck with getting it sorted as it's lovely when it all works as it should!

http://www.retrobike.co.uk/forum/viewto ... 68285b24d7
 
AdrianStreet1973":2c3p8fiq said:
Update on the DBR Axis TT SS conversion....

That tensioner has got to go I reckon. To eliminate the SRAM 'Snap Lock' link I took that out and tried to reduce the chain length to its absolute minimum at the same time (maximising the wrap around) and.....

........jump, jump, jump :x .



I had a simular problem with chain jump, compounded by the fact I have a chain stay mounted U brake.I replaced the single speed chain with a half link and changed the rear cog to a 16T (coupled with a 34T front )
I had a tensioner fail, but have replaced it with a 4 Jeri, which is allot more robust :

http://www.retrobike.co.uk/forum/viewto ... c&start=30
 
It's probably not of critical importance but:

sdc11391_130.jpg


That loop bit off the jockey wheel is meant to be underneath with the chain running through it. This would also let you position the tensioner higher up (nearer the stay) to start with and give more scope to tension downwards, if you see what I mean.

Half-link chains are horrid things. A single half-link, though, can be useful :)[/quote]
 
Or do what I di bin the tensioner and fit a rear mech, works a treat. I am after funtionality not looks. I ended up using a short cage road mech. If I were you I would stop faffing and do that.

I was out on Sunday for a few on it for a few hours in the field of Suffolk abusing it and not a single skip. The main problem I found with the tensioners is the play in the arm moving the jockey wheel out of line with the chain. The play was not there on a new tensioner but after it is used it came in quite quickly. Also like a previous poster the spring that keeps the tension popped out on one tensioner body thus rendering it usless. I think they are a wast of time although I have heard good things about the Gusset ones.

Previously I have great sucess with a Blackspire BB mounted tensioner and E-thirteeen do a good range of tensioner with intergrated chain guides. This is the way my other single has been done and the way I would recomend for easyfaff free setup.
 
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