# how much slack can i get away with on fixed



## Rohloff_Brompton_Rider (21 Jul 2009)

hello all,

i've been riding my full sus bike ss without a tensioner for about 2 weeks now. i have a half link chain so i can get the perfect chain length including allowing for chain growth, this does leave it a bit slacker than your typical ss. i hasn't slipped skipped or missed a beat. now i fancy trying to do a fixie conversion using an old sprocket drilled out to fit the disk studs. do you think it will work ok with so much slack? i've been really hammering it on the trails to see if it will skip but so far it hasn't. bonus as well, i don't have the whirring noise of the tensioner (dmr spring type), nice silent ss at last. just fancy seeing if it would work fixed for commuting on tarmac.


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## RedBike (22 Jul 2009)

I'm glad you put commuting tarmac on the end of that post. I was rather worried for a bit. I much prefer fixed wheel to SS but I wouldn't dream of trying to ride fixed off-road. I have enough trouble with fixed wheel on the road!

If the chains slack on fixed wheel you get this annoying jolt / delay as the slack in the chain is taken up, the chains also far more likely to come off. Your best bet really is to try it and see how you get on. 


If possible you want to keep a rear brake. If the gearings high enough to pick up some speed on the downhills then it's just too high imo to provide any form of controlled leg braking. 

Using your legs to brake via fixed wheel will put your frame under huge stresses. I don't know how this will effect your suspension linkages? I don't think i've ever seen a full suspension fixed wheel bike!


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## RedBike (22 Jul 2009)

Perhaps you could just get a very cheap old steel road bike and convert that to fixed wheel instead?

That would save having to switch your MTB over all the time between fixed and singlespeed and a road bike would probably be easier for a tarmac commute.


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## Rohloff_Brompton_Rider (22 Jul 2009)

just something i fancy doing red. i did think about the delay because of the slack. it isn't going to cost me anything so i might give it a go later on today maybe tomorrow. i have seen someone on the trails with a fixie. he did the rivington carnage on it and was way in front of me. he did have both brakes tho.


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## RedBike (22 Jul 2009)

Btw, i've cracked. The MTB is now single speed ready for setting off and riding the entire pennine bridleway (Including the MTL) tonight. 

This ride is either going to convert me or put me off for life!


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## Rohloff_Brompton_Rider (22 Jul 2009)

hehe she got you. yeah the pbw is going to be tough going ss that's for sure. good luck.


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## Joe24 (22 Jul 2009)

You need to practicing your pedaling if you get a jolt in the slack spot!!!!
I have a slack spot on my fixed, and dont get a jolt at all, or anything for the matter.

You can get away with a decent amount of slack.
I found i can have more slack now im running an all 1/8th drivetrain, rather then 18th chain and chainring, and 3/32sprocket. I used to hear the chain jump more with thr 3/32 sprocket.


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## RedBike (24 Jul 2009)

shauncollier said:


> hehe she got you. yeah the pbw is going to be tough going ss that's for sure. good luck.



She actually told me NOT to go single speed. It was the mud that forced to change. 

I didn't know what to make of single speeding. 34/18 was seriously slow with fresh legs on the road. I just kept constantly spinning out. With tired legs I struggled on the slightest uphill drag. 

btw, I didn't even make it to the start of the MTL, 20+hours riding with some seriously heavy camping gear was more than enough for me.


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## alecstilleyedye (25 Jul 2009)

i've found that having butterfly wheel nuts helps get the chain tension perfect, very easily. i think it may need to be done before each ride though.


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## Rohloff_Brompton_Rider (25 Jul 2009)

hey red,
you planning the weekend we're meeting up in september as a ss run?


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## RedBike (25 Jul 2009)

Having tried single speed my preference is still for gears so by September i will _probably_ have gears again. - Only time will tell though. 

I'm still seriously looking for a 29er that will take a rack. There's a strong chance that will either have a hub gear or single speed.


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## RedBike (25 Jul 2009)

Have you figured out how to do this yet?

What gear ratio are you planning to use? I don't think I would apprechiate trying to spin down a bank with slicks on using 32/16


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## trio25 (26 Jul 2009)

red I think hub gears make sense for you!

Fixed full-suss sounds crazy!


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## RedBike (26 Jul 2009)

Yes, I would definately prefer a hub gear. 

I'm looking at getting it single speed to begin with (to save money) then upgrading to a hub gear at a later date.


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## Rohloff_Brompton_Rider (27 Jul 2009)

was crazy, didn't try it. the sprocket i had in mind already has holes in the wrong place. i am thinking of ordering one from velo solo. but got to deal with commute problem first.


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## der alt (4 Sep 2009)

Dunno if this is any use to you shaun .i converted a specialised rockhopper 93 to ss back in January just as a trainer type of thing first couple of tries getting the chain to the right length was a bit hard working out wise .once i had got it sorted out it worked fine .i was thinking of converting it to fixed but i decided to just buy a fixed machine and try it from there the chain slack i had given it was an old mtb chain i was using was maybe a touch too much but now that the chain has stretched out and cutting a link out seems to have sorted out the slack/clunk when pulling away ..below is a pic of said machine it ain't pretty but it works well


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## RedBike (4 Sep 2009)

Sorry Der Alt, we can't see your picture. 

You can't put a fixed sprocket on a 'normal' freehub. You have to have either a single speed MTB hub that can accept a lockring (rather rare!) or mount a sprocket to the disc part of the hub and use a rim brake / no brake

IE Velo solos cogs


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## bonj2 (4 Sep 2009)

So let me get this straight, not only are you running a full susser single speed, but you are also now trying to bastardise it into a *_fixed_* and due to the obvious problem of it having not only vertical dropouts but wider 135mm vertical dropouts you are considering embarking on all sorts of drilling and bodging to satisfy your determination to get it to work.
Are you *_mental_*?
Normal people would take all these hurdles you are facing as a sign that this isn't meant to be done. Try joining them.


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## Joe24 (4 Sep 2009)

Its simple what he needs to do.
Get a back wheel that fits that takes a screw on block, then just put a fixed sprocket on.
Put it on tight, lock it on, and you have yourself a fixed.

You will probably/maybe/more then likely die/cause serious injury to yourself.

Don't do it, take some advice.


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## Rohloff_Brompton_Rider (4 Sep 2009)

nope, red got it right. just need to order one. will defo be trying it for winter. as for mental, no just intrigued. only a bit of fun.


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## Rohloff_Brompton_Rider (4 Sep 2009)

bonj,

what drilling? it's 6 bolts


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## Joe24 (4 Sep 2009)

shauncollier said:


> nope, red got it right. just need to order one. will defo be trying it for winter. as for mental, no just intrigued. only a bit of fun.



Oh ok.
Do you have money to just throw away at things?
If so, feel free to buy me a new chainring, sprocket and chain, front wheel........


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## Rohloff_Brompton_Rider (4 Sep 2009)




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## Joe24 (4 Sep 2009)

shauncollier said:


>



How old are you?
What bike do you have?


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## RedBike (5 Sep 2009)

Joe, as far as I can tell it's a relatively cheap convertion; and he's only planning to ride the bike on the road. He just takes his existing wheel, removes the disc rotor then mounts one of those velo cogs in it's place. 

There's two minor problems with it though. 

He can't run a rear brake. His frame is disc brake only. 
When the suspension compresses the chainstay length changes slightly. So he cannot (even if he had sliding dropouts) run a tight chain. 

However, a front only disc + the ability to brake via the pedals should be enough for road use provided he doesn't go nuts. He will probably be able to get the chain tight enough to try it out for a bit but chain stretch is going to be a major pain.


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## Rohloff_Brompton_Rider (5 Sep 2009)

what's my age got do with it? but old enough to be your father young man!!!


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## Joe24 (5 Sep 2009)

RedBike said:


> Joe, as far as I can tell it's a relatively cheap convertion; and he's only planning to ride the bike on the road. He just takes his existing wheel, removes the disc rotor then mounts one of those velo cogs in it's place.
> 
> There's two minor problems with it though.
> 
> ...



Well, hes got to get his chainline right.
All the bouncing around thats going to happen, if he hits a bump and the chain slackens, it will come off.
On my cheapo fixed, the chain slackens because the wheel is only on quick release, which doesnt hold it tight enough. Meaning going anywhere and doing over about 15mph(at the most) on it, is dangerouse, the chain clunks and if i did go any faster, the chain will just come off.
Stupid idea if you ask me, would be much better to just get an old frame and build that up, but never mind.


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## Rohloff_Brompton_Rider (5 Sep 2009)

chainline is already perfect, done over 300 miles on rough bridleways already with no tensioner and shoot loads of slack to accommodate 5 inch travel. never once skipped or derails since i put on the half link chain. 

my only concern was whether or not the slack i'm running will cause knocking as the slack is taken up when the pedals stop.

joe24,

have i upset you in a previous life? you seem to be very aggressive towards me on this and other threads. please either pack it in or stop replying to my questions. you seem to think you always know better. however, your advice is always incorrect.


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## Joe24 (5 Sep 2009)

shauncollier said:


> chainline is already perfect, done over 300 miles on rough bridleways already with no tensioner and shoot loads of slack to accommodate 5 inch travel. never once skipped or derails since i put on the half link chain.
> 
> *my only concern was whether or not the slack i'm running will cause knocking as the slack is taken up when the pedals stop.*
> 
> ...



Yes, it will do.
I might go out and film my cheapo fixed with a slack chain, and pedals spinning, and me moving the back wheel around(like i guess the chain would be getting bounced and show you the chain coming off)

I dont really get what you mean about me being aggressive towards you though. I am, nearly always right though. Thats a FACT!


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