Singlespeed & Fixed Gear - cog slipping, can't seem to get it tight enough?

so i just finished building up my first fixed gear, and im noticing that if i try to accelerate very quickly or skid, my cog is slipping. I can't figure out how to get the cog and lockring tight enough so that this doesnt happen (the hubs are new and definitely not stripped). I tightened the cog down with a chainwhip and held it there while i tightened the lockring down with the proper spanner. my only difficulty is that the lockring spanner doesn't fit on really snugly when the chainwhip is on the cog, because the chain gets in the way a little bit. any suggestions? i thought about that rotafix method, but the chain is then still in the way as im trying to tighten the lockring.

thanks.

Is the cog coming loose before you even get a chance to put the lockring on? The lockring should hold the cog in a fixed position, so if the lock ring isn't staying tight you might want to check the threads. What kind of hub/cog/lockring are you using?

Take it to a shop or Sport Chalet

They'll do it for free.

Ride your bike up a steep hill close to your house (to tighten the cog) and then cruise back to your garage without putting backpressure on the pedals, then use the lockring tool to tighten the lockring. You shouldn't need to hold the cog with a chainwhip while tightening the lockring. I've never held the cog while tightening my lockring and haven't had any problems with cogs loosening.

loc.tite. make sure you choose the right color.

might be your chainring sliding around on its bolts. just something else to check out.

uhh, i dont know if you just have the names mixed up but you should be using a specific wrench, not a "spanner". if you are actually using a spanner, you should invest in a proper tool. ill stop being an ***** and simply recommend you ride it and coast back to your home/shop. then use the lockring wrench and tighten that sucker down real good. if you have been doing something like this already and your still getting the bad results, go to a shop. maybe you have a defective part (probably and hopefully not) and maybe for a few bucks theyll get everything workin great.

spanner = wrench.

lockring spanner, lockring wrench are the same things. Lockring pliers, on the other hand, are different.

Like others have said, holding the cog on with the chain whip does absolutely nothing but get in your way. Tighten the cog as much as you can with the chain whip. Then do the same with the spanner to the lockring. Ride around for a bit, and check the tightness of the two. Do this from time to time until you definitely have it on there.

better yet use the rotafix method on the cog. throw a rag between the BB and the chain if you dont want to scratch the paint. Then tighten the lockring with the spanner.

As mentioned before, first check your chainring and make sure it's on. Couldn't hurt.

Second, don't use the chainwhip while you are tightening the lockring. Tighten the cog, take off the chainwhip, then tighten the lockring. A good way to tighten the cog is to put a u lock in the crank through the arms and around the downtube and then turn the rear wheel counterclockwise.

uhh, i dont know if you just have the names mixed up but you should be using a specific wrench, not a "spanner". if you are actually using a spanner, you should invest in a proper tool. ill

Pwnage is so much more enjoyable when self-inflicted

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