man is bastard

okay so i just converted my univega to a fixie and when i go its all good fully functional but when i skid my cog feels like it moves about a quarter turn and i smash my knee in my head set, then when i pedal forward it does the same thing just vice versa, so basically everythings cool i just cant skid until its fixed, wtf help me out, i took it off and tightened it more and it worked for a while but today it did it again, let me know whats up thanks.

Scrodzilla

You're screwed. Set your bike on fire immediately.

I jest. Tighten your damn cog then your lockring, son! Why do people find this so hard to understand?

f50fan

Cog too too loose? Deductive reasoning would say to tighten it some more.

This isnt a technical problem, you've just got to beast it and tighten that sucker down hard as you're humanly capable of doing.

Dr. Banzai

A. Didn't buy the right tools
B. Too cheap to go to the LBS to get it done.

I hope the OP is "A." and this gets solved for him fast.

PedallingATX

Tips:

-Put lots of grease on those threads.

-Tighten cog down and lockring as tight as you can, then go ride a few miles (mash hard on these few miles and avoid skidding/back pedaling). Then tighten the lockring down even more.

-Make sure it's not just that you chain is loose. If you have a loose chain, you might misinterpret it as your cog slipping.

man is bastard

thanks dudes, i mean i pretty much guessed it just wasnt tight enough cause i dont have the necessary tools i just used a rubber mallet and a flat head but im just going to ride to the local bike shop and see if they'll let me use there tools or some**** but word up glad i found this forum board thanks alot, guys stay up.

Scrodzilla

man is bastard

haha well i used a lockring tool this morning at biketech and now its perfect =]

Leukybear 

You should've used their chainwhip aswell...

cg1985

Why is it....

That fixed gears use threads/lock rings to being with?

Coaster brake bikes, well some, use C-Clips, and I could imagine that being a more efficient method, since the cog isn't supposed to move anyway.

Or why not use a system like cranks? A square taper on the drive side of the axel that the cog fits on to?

I mean I am sure there are reasons, but why not?

Is there a superiority to the threaded systems? Lighter maybe? Simpler? (can't imagine something simpler than a C-clip though)

TejanoTrackie 

Threaded cogs and freewheels have been used forever. In the 1980's road bikes changed over to freehub cassette systems, but track and BMX retained threaded systems. Threaded cogs with lockrings work fine when installed properly and good quality parts are used. The vast majority of track bikes that are raced on the velodrome use this traditional system, and riders are constantly removing and installing different sized cogs without any problems. There are a few splined systems, Miche and Easton, but I've only seen a few being used (I do have a Miche setup on one of my wheels that I now use on the street). There is also the ISO bolt-on cog system. Bottom line, if it ain't broke don't fix it.

blickblocks

I hate this mantra.

cg1985

Agreed. It's a stupid saying that only applies in few situations. If there is an improvement that can be made, than why not do it? not saying my suggestions are an improvement, but it seems to me that either of those two systems would eliminated cog slippage. (unless there is a catastrophic failure).

TejanoTrackie 

In 35+ years, I've never had a problem with "cog slippage". You are talking about a solution to a non-existent problem. If you want to trash me for my old school attitudes, let me also say that I believe in the KISS principle, and I don't mean the band. Fire away!

cg1985

Sensitive much?

a non existent problem for you. However at least once a week we get someone on here asking about cog slippage. So it is not a 'non existent problem'

I've never had a problem with it either. But I can see a reasonable issue with it. Hell, I wasn't even suggesting necessarily that it was an improvement to begin with, I was simply wondering WHY it had not been done. Seems mostly tradition. Which is fine, but just because we don't like the 'aint broke don' fix it' manta, doesn't mean we are 'trashing you.'

Hell Blicks probably didn't even mean it specific to this topic.

Basically, you're being really defensive for no reason.

tgscordv6

I think we should make a sticky to remind newbies to tighten their lockring and cog with proper tools before riding. Honestly, I am sick of "slipping cog" and "stripped hub" threads every week.

Scrodzilla

I don't really think TT was being overly-defensive here. He's pretty much right.

We get people asking about "cog slippage" so often because for whatever reason said people can't seem to absorb the fact that proper tightening of a cog/lockring is important. The only non-existent aspect of the problem is user error.

AEO

The tools are not broken and the system isn't broken.
It just has a high learning curve, that's all.
The learning curve is actually not that high, but if you don't have the right tools and decent quality parts, then it can be a problem.

With that said, I like the tomicog/velosolo solution of using the disc brake side of 6-bolt disc hubs for just riding around town.

fuji86

That sounds kinky ?

Johhny B

Should just rotafix it.

f50fan

Hope this doesnt become the standard answer to "cog slipping" threads

mparker326

https://www.fixedgeargallery.com/revi...aker/index.htm

Solution to problem.

fuzz2050

I like the Tomi-cog myself. No need to make a new standard when the 6 bolt disk works just fine.

The threaded version does work just fine; but that's the thing, it's just fine. It requires specialized tools, and has a small inherent risk of expensive damage to parts if you aren't paying attention. It's like a square taper crank, it works just great, but every time you take one off, you risk being an idiot and striping the crank. There's nothing wrong with it, but if I had the money, I'd go to a splined or bolt on interface.