Bicycle Mechanics - dont laugh but bike hiccups when i pedal

what causes this
i went for a ride today and after i went through a deep creek and like -15 below my feet still red and very cold my bike got the hiccups when i pedal the chain kinda skips a beat when i try to shift to a lower gear it like hiccups and slams to the motion of me pedling ... understand..?
kinda hard to describe but i didnt really do anything different how does one fix the shifter or what ever is making it hiccup.?

Hmmm...I think I know what you mean. I don't think it was caused by your riding through the creek, but maybe something you hit. Or, it could have come from something totally different!

Anyway, I think your rear derraileur is out of line. Standing from the back, look to see if the derraileur pulley is lined up with the cog that the chain is on. If it is not, turn the adjustment knob until it is directly in line with the cog. See if this works.

I think it might be a stiff link in the chain. Look for one that does not straigthen out when it is between the rear cogs and the chainwheel, or doesnt run smoothly over the sprockets and derailler idlers when you turn the cranks backwards.

ok thanks guys il try that 1st thing in the am !!
il let you know what happens

well everything was aligned and i saw a screw that looked like it was gonna fall out on the gear thingy maybe its the derailer.?
i tightened it and now it dont shift gears anymore...now i done it, hiccups stopped but bike dont shift at all now... so im guessing i need to uyn tighten that screw a little bit..?

Ut-oh, boyfriend! That was one of the shift limiter screws. There are two of them and they keep your derailleur from shifting too far in either direction. It sounds like maybe a trip to the friendly mechanic at your LBS is in order. Mention my name. If he knows me, it might get you a discount!

Since you messed the derailleur up with a screwdriver, you could try to fix it with a screwdriver. Read the instructions at Park Tool (http://www.parktool.com/repair_help/FAQrindx.shtml). You probably won't mess things up too much more than they already are.

As for the "hiccups." Riding through creeks and such tends to dirty up your drivetrain. Clean the chain and the derailleurs with citrus degreaser. Oil the chain. Put a drop of oil on the derailleur pivots, too. See if that helps. If the old clean-and-lube doesn't do the trick, then look for a stiff link. If that fails, get thee to the LBS fer sher.

:D :love:

What do you do with a stiff link? Do you just clean and relube and that takes care of it?

You use the chain tool to push the pin a bit further into the nearside links. This means the pressure of the chain tool must be exerted against the middle of the chain and not the far side of the chain.

A stiff link can usually be cured without resorting to tools. Once you find the stiff link, grasp the links on either side of it and bend back and forth. That should do the trick.

Thanx for the info. I also found on parktool.com a description for fixing.