reagle

Ok, so about 2 weeks ago I was on my daily ride home and I stand up and begin to pedal hard. On the first down stroke, it felt like the crank just gave and slipped, my foot flew out of my strap and I almost racked myself on the TT. It freaked me out, so I slowed down and continued my ride home. Then coming to a stop sign, I begin to break hard and it does the same thing just the other direction, again scaring the crap out of me! Now I am almost home and just ride very carefully home.

I took it to the local shop thinking it was the BB or something, and he looked at, messed with it, and it was tight. Also nothing was weird with the cog or chain. I couldn't get it happen of course when the mechanic was riding next to me, but it happened several more times before I took it to the shop, and it will happen again. Which makes me weary to ride it.

So any ideas?

Oh, it's a Kilo, stock drive train

Thanks!

ianjk

Your lockring/cog is loose, or your hub is stripped.

Bring it in to a good shop if you don't have tools.

reagle

lockring/cog isn't loose I know. How could I tell if the hub is stripped?

nuhtowel

take the lock ring and cog off and look to see if the threads are still there

evilcryalotmore

Lmao. When you take it off and a **** load of rocks come out and metal debris.

Buy a good wheelset. And clean your threads lub them well. Get a new cog and lockring. New chain, New frame, New bottm bracket, new crank arms, New seat post, New clamp, F the headset. Ride it like a unicycle.

Scrodzilla

lawlz

dbwoi

lockring is loose. happens to me because all i have is a flathead screwdriver and hammer to tighten my lockring. its really ****ing annoying.

Scrodzilla

yummygooey

Buy a lockring tool.

jim-bob

Just get a rock, all these tools are a ploy to siphon money from your wallet.

dev0415

lol buy a friggin lock ring tool...its like 15-20 bucks...having slippage aint no joke...my friend had it on his new masi...almost ate it down a hill...

Squirrelli

Hmm.

leed

The bottom bracket has absolutely nothing to do with it. You'll notice that the bottom bracket spindle is designed to spin within the bottom bracket bearings. Even if it was loose, you wouldn't lurch forward or backwards under any pressure. In fact, you have a better chance of your crank arms being loose and causing the issue than your bottom bracket being the cause, and that's considering the fact that you have an ISIS BB.

Needless to say, your cog is slipping. Your cog is slipping because it was not tight enough and your lockring was not tight enough. Either that or you have monstrous legs and you burned out for a second there.

FastJake

To the OP, as everyone has said, your cog/lockring is loose. Take them both off and make you didn't F up your hub. Don't ride the bike again until you do this.

Lightly rotafix your cog before you put the lockring on. Then the lockring just becomes an extra safety measure. I don't have a lockring tool and I haven't had anything come loose even with skidding. I also used a flathead and hammer for the lockring.

Kayce

Since every one has decided your wrong, rather than trying to help you find other possible options, here are the other things I can think off in descending likelihood:

Loose crank arm bolt
Loose chainring bolts
Stripped crank arm
Stripped bb spindle
Loose axle nuts on the rear wheel

Great Pan

long ride... feels good man.

vw addict

It's funny how he said he took it to a shop and the guy looked at it and couldn't figure it out. I would not go back to that shop probably...

Deshi

That sounds exactly like a loose cog.

Forget what the shop did. Loosen the lockring, check the cog, tighten once you find out it is loose, cinch down lockring. Problem Solved!

Scrodzilla

reagle - your lbs sucks.

ianjk

none of these fit the OP's description of the problem.

Scrodzilla

+1

midship909

if the lockring is tight most likely the hub is stripped

radd

lockring thread is mostly stronger than the hub.. get better hub, rip you off now, but it will save money in the future