homemade singlespeed tensioner and chain length

[goose]

Hi everybody,

I just finished transfering my bike to singlespeed. It's cool, but I'm not super happy with the chain length/tensioner setup...

The homemade tensioner is a rennen/fresh knockoff I made with only a bandsaw, drillpress, and file. Worked out pretty well for the 45 minutes it took to make. I used an MRP roller ($9) and some vbrake booster spacers to get the chainline right. Onto the pictures:

http://www.cim.mcgill.ca/%7Eandrewg/norcoteamtrials/singlespeed1.jpg
a closer look:
http://www.cim.mcgill.ca/%7Eandrewg/norcoteamtrials/singlespeed2.jpg

So my question is really regarding half links. The difference between too tight and the next chain lenght is quite a bit, so I figure the only way to get this chain a little higher, so I can use push up mode and/or get the clearance better is to use a half link. So, are they generic? do they work with any chain? Thanks for all your help, and I hope this inspires some others to try to make their own tensioner, it's really not hard:)

goose

[epet]

is that a (1/8"?)nine speed chain? i think the most common half links are for single speed (3/16"?) chains. that tension thingy looks sharp (as in stitches not spiffy). still, It's cool you made your own.

someone here will tell you all kinds of brand names and specs and how wrong I am and the proper technique for using the search button, but your already half way there by figuring it out for yourself, don't stop now.

[Gaps720]

i'd mill that bitch in to some spiffy shape...:eek3danc:

[felix]

I also made my own Rennen:

http://www.observedtrials.net/album/data/500/medium/DSC01537.jpg
http://www.observedtrials.net/album/data/500/medium/DSC01538.jpg
http://www.observedtrials.net/album/data/500/medium/DSC01540.jpg

At first I was in the same situation as you. I had to setup the tensioner so that it pushed the chain down.
The other way didn't work, because the tensioner hit the chainstay without tensioning the chain at all.
First improvement was a bigger pulley, but that still didn't help.
I then moved the cog more to the middle of the hub, so that the chain could clear the chain stay.
Now it's working perfectly.

P.S.: sorry for hijacking your thread.

[goose]

woah, nice work felix. I was thinking of trying to modify my tensioner so I can push up more rather than use a half link. I'm not a big fan of the half link idea, cause if used with a kool chain or whatever, the half link will definitely be the weakest. In the shop today I'm going to try to raise up my roller about 10mm and see if that gives sufficient tension in the push up position. I'm totally addicted to the look of the push up position cause it gets the bracket almost completely out of the way.

And epet, if you think it's necessary, I'll will go and buff all the edges so it's not so sharp:)

[toyota200x]

I am so happy to see people making their own parts. Smooth out the corners on the tensioner before you get hurt. :eek3: Great looking parts.

[myergin]

felix, post a full pic of your bike. just curious.

[Soapster887]

is the entire thing pink?

[goose]

New mod inspired by felix:
http://www.cim.mcgill.ca/%7Eandrewg/norcoteamtrials/singlespeed3.jpg

Seems to work well, although I haven't ridden it yet. Props to felix for the idea.

FINE FINE FINE. I'll smooth the corners... sheesh.... bunch of purists here. My prototype was made in a hurry, with no attention to any asthetic details. Now that I know what to make, the I'm thinking of making a second one that's stronger, lighter and better looking.... maybe even with some ghetto goose graphix... hehehe...

enjoy,
g

[Giant1118]

good job, i know of someone making a pretty sweet tensioner out of 2 spoons. We will see if it works

[goose]

I can see that. Spoons could do the trick, gonna be funny to see how it comes together:)

[epock7]

good job, i know of someone making a pretty sweet tensioner out of 2 spoons. We will see if it works


You have my attention...

[guumer]

this is my first try with the spoons it was a prototype if you wana flame it go ahead you all know you want one hahahahahhah

[felix]

is the entire thing pink?
No, only the right droput and 10cm of chainstay/seatstay. ;)

[epock7]

Haha. Okay Guumer, you're gonna have to explain how that's gonna work...

[goose]

that is SO GHETTO!

I wanna see it hooked up and working!!!

[Giant1118]

it worked pretty well only problem was there was hardly any room for chainline adjustment. i have to say it looked sweet, and was hilarious.

i swear to god this kid is the KING! of ghetto...hes also made a bash buard and hanger (not out of spoons though)

[guumer]

this is some of my other stuff
the hanges is steel and is so good

[jaimer]

hahah the bash wieghs so much it adds like 2 pounds onto the bike

[guumer]

ya fuck you man its not two its like one now and when tommy rides my bike he cant take chunks out of my fraim

[epock7]

Thread officially hijacked.

[Giant1118]

just to get the thread back on topic, what u could do Andrew is bend the aluminum so that it cleares the chainstay and u can have it pushing upwards

[goose]

which andrew you talkin to? Me? I'm thinkin about that, dan, but I don't how to bend 1/8" aluminum accurately It's really stiff stuff... In my next version, I'll be using 1/4" aluminum, which should be even harder to bend. My little bent sheed aluminum bracket hack is OK, and it gives a little 'spring' effect, so I'm content for now. I wanna figure a way to make the thing less fugly, though.

[Giant1118]

if yer cutting the alu out of a longer peice of aluminun keep it long (more leverage), put it in a vice and put 2 angled bends in it \ \ in opposite directions. Also makes it look good.

If you solely want to make it look nicer then just bust out the angle grinder.

[guumer]

you stoll what you saw my dad do Dan you fucker

[jaimer]

haha donny shut up and go mow the lawn

[guumer]

fuck you jaime go lern to ride trials

[epock7]

:hsugh:

[guumer]

do any of you have problems with the tenshon my when i get it right it is tight in some spots and loose in others i think i have to change my front 22 but i dont know help plz

[epock7]

Loosen all of the bolt on the chainring a little bit. Then turn the cranks a few times. It should even out then. At least that's how to with a fixed gear.:dunno:

[muddyfox]

Get a sheet of 1/4" aluminum and cut out the shape you want with a plasma cutter.....

[epet]

or a bandsaw if you want it to look nice

[will4eva7k]

I also made my own Rennen:

http://www.observedtrials.net/album/data/500/medium/DSC01537.jpg
http://www.observedtrials.net/album/data/500/medium/DSC01538.jpg
http://www.observedtrials.net/album/data/500/medium/DSC01540.jpg

At first I was in the same situation as you. I had to setup the tensioner so that it pushed the chain down.
The other way didn't work, because the tensioner hit the chainstay without tensioning the chain at all.
First improvement was a bigger pulley, but that still didn't help.
I then moved the cog more to the middle of the hub, so that the chain could clear the chain stay.
Now it's working perfectly.

P.S.: sorry for hijacking your thread.


nice pink colour going on

when did u get a pink frame?

got any pics of the whole bike and hope u got a new vid coming out for us all :)

[felix]

nice pink colour going on

when did u get a pink frame?

got any pics of the whole bike and hope u got a new vid coming out for us all :)
Got it about a month ago.
Check btbike.com for pics!

[muddyfox]

or a bandsaw if you want it to look nice

Are you kidding me??? do you know what a plasma cutter is?

[va_tick]

Plasma cutters are f#$#% nasty!!! You can practically cut through a bank vault with one...pretty accurate to...big money though

[muddyfox]

:p I have one at work

[goose]

Hi,

I'm just writing to close this thread out. I've made final modifications to my tensioner, and had a few winter rides with it. It works well and looks smooth.
http://www.observedtrials.net/album/data/500/DSC01249sm.JPG
http://www.observedtrials.net/album/data/500/DSC01248sm.JPG

[epock7]

looks good. Glad to see you rounded over the corners nicely :) . I'm guessing that its pretty tough.
I wish I could find a 10x1.00 bolt somewhere. :wtc: I'm convinced they are like santa clause. Everyone says they exist, but I haven't found one yet.

[guumer]

why do you need a 10x1.00 bolt

[tomacropod]

presumably that's what the King HD axle takes. You could get a track nut or other axle nut (10 * 1.0) and a piece of a shimano/ISO axle (10 * 1.0) and weld them together, making a bolt.

- Joel

[toyota200x]

Man that tensioner looks super good. I almost feel like getting rid of my derailer and going SS. :p

[goose]

m10x 1.0 is the thread of the derailleur hanger. I wish I could get one also, so I could just thread directly into the hanger rather than use an M6 nut and bolt. But oh well. The M6 solution is prolly a little bit lighter:) I weighed the tensioner, and it's about 130gm. My derailleur was over 300!

I haven't landed on it yet, but just in case I've found a small plate of 1/8" Ti and a spare piece of 5mm 6061 to make extras out of. It's tucked up so high, I think it'd be hard to hit.

[epock7]

Yeah, I need one for the der. hanger. Right now I just have an 8x1.50 and a nut cause they are easy to find. Joel, that's not a bad idea. I got a ton of old shimano axles lying around.

If I find some 10x1.00, I'll buy all of them and randomly mail them to OTN members.

[tomacropod]

10 * 1.0 is also an axle as I said, so yeah using the hollow shimano axle as a shaft for a bolt would be very weight weenie! Cool if you can make it work.

- Joel

[eastcoaststeve]

looks good. Glad to see you rounded over the corners nicely :) . I'm guessing that its pretty tough.
I wish I could find a 10x1.00 bolt somewhere. :wtc: I'm convinced they are like santa clause. Everyone says they exist, but I haven't found one yet.



http://www.boltdepot.com



these guys have everything you could ever want in metric fasteners, no minimum order, ship quick, and you choose the quality of the stuff. i ordered a buch of mixed stuff for projects that were stalled on odd bolts...just like xmas when the box hit my mailbox.
yes, i checked, they have 10x1.0....

[goose]

I guess you could just fuse an axle bolt onto a section of axle with jbweld or something, eh? That'd prolly work, right?

[epock7]

lolz. Meh, that should stay.

If I finally give up rigging stuff, I will probably just order a bolt from those guys. Thanks for the link eastcoast. Now if they only sold taps...