another chain tension question (drive - not cam)

[12thmonkey]

i did a bunch of work on my bike this weekend, and am finding out more about it. i'm becoming less and less confident in the previous owners' maintenance.

i measured the slack in the chain, and i know it needs to be tightened. But what i was wondering, is the chain supposed to slide along a plastic cover on the swing arm when it enters the front sprocket? The area i'm talking about:

Or is this just happening cause there is too much slack in my chain?

[12thmonkey]

Also, how do you know if you should replace your chain? Mine is super crudded up...and very dry. Makes me think it definitely wasn't lubed on any sort of regular basis. i just read the new rider thread that was just posted, and it sounds like replacing the chain is a doozy.

[coll0412]

Yeah the chain slides on the plastic peice that attaches on top of the swing arm...

As far as replacement, a dirty chain most likely is not a well maintained chain....

[scratch]

I just read the new rider thread that was just posted, and it sounds like replacing the chain is a doozy.

It's not that bad, just remove the part about him trying to lube the clutch cable:

I started by removing the shifter lever and the cover over the front sprocket.  Setting the cover aside and letting it dangle by the clutch cable.  I loosened the rear axle bolt and kicked the rear tire forward to give myself more chain slack, and I removed the front sprocket with my new circlip pliers (glad I knew that was coming).  I got the chain off the sprocket, and I was able to attack the crud in the cavity.  Taking a small flathead screwdriver, I scraped over a cup of black, oily, gritty gunk from the inside of the cover and from around and behind the sprocket.  Before I put it back together, I plan on cleaning that area more thoroughly, but it's good enough for now.

I turned my attention back to the chain, and I located the master link. I managed to pry the clip off the front, but the plate behind it might as well be welded in place.  I tried prying it off with screwdrivers, grabbing it and pulling with vice grips, and even some foul language.  Nothing worked.  At that point, I was losing my light, so I decided to hang it up for the evening.

Tonight, I plan on taking out my old friend the Dremel and getting that master link apart.  Then I can try putting that new chain and sprocket on.

At least the next time I have to do a certain task, it should be much easier.
I hope it helps someone else trying to do this stuff.

Do you have a Dremel, or a chain breaker?  You can use channel locks to get the new masterlink plate on (not the circlip).  Sometimes having the right tools does help.  And, for suggestions, we are always here.

To clean out the sprocket cavity, I suggest spreading out newspaper under the bike to catch a lot of the crud, rubber gloves and/or a sock (or two) to clean out the cavity, plus the flat screwdriver.