I am posing a question and making suggestions all in the same post:
How do you get those rounded off bolts off your old CB? My current dilemma is my oil filter bolt that is tight as &*$%^& and equally rounded off.
Here are some tips/tricks I found thus far:
1) Good quality vice grips and BFH (hammer)
2) Welder (weld another nut onto it)
3) One technique I've used to good effect is to use a hammer and cold chisel to
apply impact at the periphery of the stuck bolt or nut (in the looseningdirection, of course). If you have enough room around the bolt to swing a hammer
(the bigger, the better) and can get a good purchase on the edge with the
chisel, one or two sharp blows will almost always free it.
4) Craftsman Bolt-Out sockets
http://www.sears.com/sr/javasr/product.do?BV_SessionID=@@@@0255333746.1177693085@@@@&BV_EngineID=cdcdaddkkhkmfdjcefecemldffidfno.0&pid=00952161000&bidsite=CRAFT&vertical=TOOL&ihtoken=15) Stanley Proto bolt extractor socket provides easy alternative to removing rusted and imperfect bolts
http://www.stanleyproto.com/xhtml/literature/ProtoBoltEtractorSockets_T20266.pdf6) File the bolt head down to the next smaller size. In other words, make some fresh new sides to that bolt head. Then, use next size smaller socket on filed bolt.
7) Get a cut off wheel and slot it so you can turn it with a flathead screwdriver.
Irwin BOLT-GRIP fastener remover
http://www.homedepot.com/prel80/HDUS/EN_US/diy_main/pg_diy.jsp?prod_id=100051815&cm_mmc=1hd.com2froogle-_-product_feed-_-D25X-_-1000518159) Get a chisle or something sharp and hammer a notch into the side of the head of the bolt. Then get a flat head screw driver and put the tip of it into the notch at an angle so that when you hit it, it will twist the bolt.
<--- This is likely how the last person got the bolt off the bike last time because it has the notch in it10) My favorite tool for this is a special Channel Lock Plier with rounded jaws that "cam into the fastener. It grabs so tight that it will twist off a bolt before letting go. I bought mine off the tool truck (MATCO).
11) use some big vise grips and clamp the down on it with some even biger channel locks and hit it with a hammer
Pick your favorite method, or suggest which method you think I should use for the oil filter bolt, or add to the list. This is a pretty common problem and others will benefit from your suggestions.