i’ve accidentally over tightened the cap while pissing around trying to install a set of cranks. any suggestions on how to get this thing off? the tool that I have (the park tool with the plastic piece on the end) keeps stripping itself, and I’m scared to wreck the cap and then not be able to get it off.
suggestions?
thanks,
-kevin
I did the same thing not too long ago. Just poke a hole in the middle of it, get some leverage and get that bad boy out without digging into the crank itself. It’s designed to give out before it causes any harm to the crank arm. You can get a new one here:
http://www.beyondbikes.com/bb/itemdesc.asp?Ic=CM-BRA-crankcap
for the princely sum of 2.99. Save yourself the blisters on your thumb your getting from screwing around with your park tool BB tool.
2.99 + 18 dollars shipping…eep!
I’ve ordered a new bb tool for $10 and am going to try that…I think I might be looking into your option though if it doesn’t work.
Do most shops carry extra dust caps? paying 6x the cost for shipping seems a bit crazy.
Probably not. It’s not exactly a common problem. They can probably get one from their distro pretty quick.
Don’t wait to get a new one to ride your bike. It just keeps dirt from getting inside your crank arm, no moving parts in there if it’s a current model Shimano crank. I rode a couple hundred miles without one and all I had to do when I got the new one was spray a little simple green in the spindle and shove a paper towel in there to get the dirt out.
Not to ask the obvious, but did you loosen the crank arm fixing bolts before trying to undo the dust cap? It won’t come off until you loosen those bolts.
I have made the mistake of trying to get it off without loosening the crank bolts. And I was following instructions from a bike maintenance book. However the shimano website instructions does tell you to loosen the crank bolts first, which is rather obvious now, but not the order the book was telling me.
haha…i had actually forgotten. I did that now, and it still won’t budge. i think my tool is pooched though.
i have not had a lot of luck with cranks/bottom brackets in the past year or so… 
I’ve done that before, I brought it in to the bike shop and they used a large wrench/pliers that could adjust how far apart the arms are (whatever those are called). They grabbed the plastic piece and turned it with that. I was like ‘doh!’…I could’ve done that!
you can get these caps at a lot of places. I bought one at excel sports boulder online. I don’t think the shipping was quite as crazy.