slipping fixed gear

parko202

i recently bought a fixed gear and have been finding that after i skid stop, or sometimes not even that extreme, just slowing quickly, the gear seems to slip when i move off again. Is it just that the sprocket is not tight enough on and how do I adjust that? I have a lock ring and chain whip for my road bike but unsure how the fixed gear side of thing varies, any help much appreciated.

Ryder

If new gear or cog shouldnt be worn. Prob just not enough tension in your chain. Should feel relatively tight when you move it up and down-if not, adjust your back wheel so that it is.

Thomas_S_Hunterson

Is there a lockring fitted to the fixed sprocket?

NeilMcEoigheann

sounds like either no lock ring or the sprocket has tightened leaving a gap between the lock ring and the sprocket so the sprocket has some movement.
tighten the lockring maybe even thread lock it tight..

blorg

Your cog is loose. It is unscrewing when you skid stop and tightening up again when you start. Rotafix the cog on as tight as you can and then tighten the lockring (remember reverse threaded.) Cog should be very tight, lockring not so much or you will strip the threads.

Note lockring for a cassette is completely different, you need a BB-type lockring tool (or a screwdriver and a hammer) to tighten.

jebidiah

bit of a hijack, is there any good instructionals on chain tensioning?

parko202

thanks for the replies, thats pretty much what i thought it was, i dont have the tool for it yet so ill just pop it into the shop 2moro. I am trying to keep my skidding to a minimum anyway as my knees are the best, can definitely see the attraction to fixed though.

crown of storms

you can tighten a lockring with a flathead screwdriver and a hammer(if you're really stuck!)
lockring needs to be really tight.

blorg

crown of storms wrote: »

you can tighten a lockring with a flathead screwdriver and a hammer(if you're really stuck!)
lockring needs to be really tight.

But not so tight you strip the threads as I have done, following the advice that it has to be "really tight!" I would concentrate on getting the cog tight enough so it doesn't slip even when skidding- Rotafix will enable this.

beans

I am trying to keep my skidding to a minimum anyway as my knees are the best

If you enjoy skidding to a stop but find your knees are suffering, try moving your crotch closer to the stem

parko202

yeah I have been throwing my weight over the front, just dont want the bike to stop too suddenly when in that position!

parko202

used the rotafix method last night and so far so good. thanks for the help. Also wondering about the gearing of the bike, its 42 16 which is really too easy a gear so was wondering am i better to increase the front to maybe a 44 or 46 or decrease the back sprocket?

blorg

Decreasing the back is generally cheaper than increasing the front, having said that I would not consider 42-16 (70.8") that far off optimal. I have 46-17 (73") and 42-15 (75.6") myself. If you don't go up hills though by all means increase the gearing, you could go to 15 (75.6") or 14 (81") and see how that goes. Riding a fixie should ideally get you used to a high cadence, at least it did with me.

stuf

parko202 wrote: »

used the rotafix method last night and so far so good. thanks for the help. Also wondering about the gearing of the bike, its 42 16 which is really too easy a gear so was wondering am i better to increase the front to maybe a 44 or 46 or decrease the back sprocket?

handy calculator to make your mind up:

http://software.bareknucklebrigade.com/rabbit.applet.html

parko202

i go from balinteer to ucd so not really anything too difficult, i guess i will use it for a bit longer and see if i can get used to a higher cadence

blorg

Well would be no harm to try 42-15 which is what I use, your route is slight downhill/uphill rather than flat, 42-14 might be pushing it.

parko202

yeah, i think i will get a 15 for the other side of the hub and give it a go. Is that the gearing you use for going up into wicklow??

blorg

parko202 wrote: »

yeah, i think i will get a 15 for the other side of the hub and give it a go. Is that the gearing you use for going up into wicklow??

I use the bike with 46-17 (73") for going up into Wicklow, although it is not that far off 42-15 (75.6").

parko202

so today going into town, I managed to undo the rotafixing, is this common? im not slamming the pedals down or anything as i would be more afraid of them breaking (still using the plastic ones)

Thomas_S_Hunterson

parko202 wrote: »

so today going into town, I managed to undo the rotafixing, is this common? im not slamming the pedals down or anything as i would be more afraid of them breaking (still using the plastic ones)

You need to put a lockring on after the sprocket!

parko202

there is a lockring on it im pretty sure, its a new langster so I would assume it has one on it already.

crown of storms

tighten the lockring- use a hammer if you must!

Thomas_S_Hunterson

parko202 wrote: »

there is a lockring on it im pretty sure, its a new langster so I would assume it has one on it already.

If there's a lockring on then it really shouldn't be getting loose.



Should look a bit like this picture, the lockring is screwed on in the reverse direction onto the slightly narrower threaded section of the hub.

blorg

You only need a lockring if you skid stop. If you use the brakes you do not need a lockring. Regarding the cog, you need to rotafix it on VERY tight if it is going to withstand skid stopping, and even then I would not trust it without a hand brake, but then I wouldn't cycle a fixie without a hand brake in any circumstances (other than at the track.)

parko202

yeah i use the brakes mostly but it seems to be coming loose even if I just skid once or twice, I don't have a lockring that will fit it so I will just bring it up to the shop to see if that's the problem. I'll try rotafixing it again and see if I can get it tighter aswell. Thanks for the replies.

parko202

ok so the cog is staying tight but have a bit of a problem with the rear hub, the nut is coming loose, not entirely sure what its called, its not the lockring. if I tighten it it stops the wheel from spinning as easily so dont reckon thats the best idea, any suggestions?

In this picture its the nut on the wheel side of the track end.

http://www.alcester-racing-sevens.com/FlipFlopHub_MG_5110.jpg

Wez

The cone nuts? They're at the end of the bearings, they hold it all together basically, would explain why it slow the rotation of the wheel!

Not sure of the exact tension, but hand tight works for me! No need for added friction..

parko202

is there any way to stop it coming loose or any reason why it would be coming loose? I was thinking a rubber bushing between the cone nut and the drop out.

Wez

Have a gander at this, should help ya out!

http://www.parktool.com/repair/readhowto.asp?id=105

parko202

i ran through everything on that list and still its either too loose (rocks side to side) or it is slowing the movement of the wheel. I think i'll just wait till tuesday and bring it into the shop, there shouldn't be anything worn at this stage