RWBlue01

First, I like doing my own work if possible because I learn things, but I don’t have a garage to work in at this location so….. If I need to go to a pro, just tell me to take it to a pro.

I have a GT mountain bike with disk breaks. It is a couple years old. I am guessing at 3000 miles. It is a little dirty, but I am not a single track mud man.

First issue, I can feel movement in the bottom bracket crank. It isn’t a lot of movement, but there is movement. I don’t think it is cracked, but this area is dirty. Big deal take it to a pro or not a big deal wait until it gets bad?

Second issue, As I coast down hill at 11-13 miles an hour, the top chain gets lose and hangs down below the frame bar. I don’t know if it is related, but I have been having issues with changing gears. I assume this is just an adjustment, but …. Only two middle gears are an issue, but it is the two gears I like to ride in. I also had the chain adjust right off the sprockets as I stopped at a red light. Odds are this is related to the chain issue as I back peddled to setup to launch when the light turned green. Big issue? See a pro? Do I just need to clean up something?

Thanks

cyclist2000

for the movement in the crank, is the movement at the bottom bracket or at connection of the crank to the bottom bracket spindle?

for the chain sagging is sounds like the rear cog spins with the wheel and does not freewheel properly. cleaning and oiling the freehub will probably fix that problem.

FBinNY 

OK, from the description, your bike could have used a bit more preventative maintenance than it got so far. I'm not a clean bike kind of guy, but yours had to be pretty bad if the BB is obscured.

The BB may or may not be serviceable. If it is have it cleaned, lubes and adjusted ASAP. If it's a non-serviceable cartridge type, you might as wheel ride it until it dies.

The chain droop is because of friction in the freehub. That allows the wheel to drag it forward as you coast spooling chain into the upper loop. This is also probably dirt/rust elated, but usually responds well to a bit of TLC, so you have another reason to visit a shop, or learn rear hub service.

Andrew R Stewart 

To add to the already posted ideas.

The "BB" looseness could be arm on axle, bearing wear within the cups/cartridge or the cups/cartridge within the frame shell. Each has their fix. A skilled mechanic can look mat the bike and discern the problem quickly. Consider going to your LBS for this look at and if parts or tools are needed for you to do the repair, buy them at that shop.

The only other reason for "chain drop" while coasting (other then the cog carrier starting to gum up) might be a spoke guard rubbing on the chain when in the largest cog. Andy.

RWBlue01

I am not sure about the terminology, but it is not the arms or peddles.

I think you are correct on the free hub. Everything gets clean this next weekend.

RWBlue01

I learned a long time ago that when you are looking for a small crack a little dirt can help or obscure the crack. As everything is not perfectly clean, I can not say for sure that I don't ahve a crack.

cny-bikeman

It's not clear who is doing the cleaning, but you have to do it properly to avoid contaminating bearings and other working mechanisms. Either take to a shop or invest some time and tools so you can properly do the work, with the emphasis on the time required to learn proper procedures. Doing something the wrong way can cost you more than taking it to a shop.

RWBlue01

This weekend will just be a pressure sprayer. It will remove the surface dirt. If it is an internal issue, it will go to a shop because I don't have a place to work on it.

DannoXYZ 

No pressure washers! They will push dirt and crud that's on the outside INTO your bearings and wear them out faster.

A little sprayer of 409 or other cleaner over the bike and wipe off with soft clean rag. Repeat as necessary to remove all the dirt and grime. Then break out the Q-tips for the corners and crevices. From the description given, plan on 3-hours for cleaning the bike. And another 4-6 hours on disassembly, cleaning all the bearings and threads, re-assembling and adjusting everything.

cyclist2000

+1 no pressure washer. it will also put water and dirt into the frame (through the vent holes) and every nook and cranny that should not have dirt in it.

RWBlue01

I think I just discovered my freewheel issue and explained why I only have it some of the time.

There is a plastic disk which appears to be designed to keep the chain out of the spokes. It looks like it use to be attached to the spokes, but now not so much. How should it be attached? How did I break it loose? Is it needed and should be re-attached or just removed?

gyozadude

+1 on NO pressure washer. Drizzle the bike with water, and wipe it clean. Get some old tooth brushes to get into nooks and crannies.

The spoke guard is clipped on using small tabs that fit between the spokes. It can brake if you shift into the spokes and the chain rides under load for any significant duration. You can order another one or visit the LBS and see if they have these in their throw-away bins. Look for the right diameter for the right number of spokes. Sounds like you may not want to remove it just yet. Adjust the Rear Derailleur to make sure the chain won't shift off the inside cog and into the spokes. Then after that, you may want to remove it... or not.

Clawed

With all due respect, I would suggest you take the bike to a good mechanic, and pay him what he charges. If I wouldn't let you work on my bike, you probably shouldn't work on yours.

400trix

And just in case no one else has said it, if you have a bike co-op in your area, you've got a place to work on your bike, as well as all the tools and a good deal of knowledge to help you get the job done.

RWBlue01

No offense taken, I already made the decision to take it to a pro. There are just too many weird things happening all at once. I haven't tinkered with anything. I just get on and ride and occasionally clean/lube the chain. Once I start messing with things...all bets are off.

At this point I am just trying to know what to tell the pro and cripple by for one more week.

RWBlue01

I have never even heard of that. Maybe after I get everything happy again.

RWBlue01

This is good news and bad news. I know exactly when and where it happened. Going up hill, shifting down, then not going up hill and falling over.