i have both of my ds 650's in the shop 1 had top end redone the other had big bore and stainless valves and head work done they got it all back together and ran dino on the big bore one the other had issues with water pump gasket any way after dino they heard clicking at the top of motor and when they took off valve cover he said the little counter weight on the exhaust broke off i have completly ran out of money and dont know what to do i cant find used cams on ebay or craigslist so i was wondering what that counter weight does and if i could run the bike safely without it any help would be appreciated if you by any chance have a used cam and would like to get rid of it pst me with email or phone # i would buy and pay for shipping

 

It is the decompression mechanism.

Never...ever... heard of one breaking - be sure to check for weirdness in the shim/bucket/lash area.

Alot of people run without them - if your battery has enough guts, you'll have no ill effects by running without it. Just makes it crank over harder, due to not bleeding off the compression.

 

the cam itself broke where the pin goes but got new one no damage to bucket, valves, or head just cant get it to fire cams are timed right not 180 off but backfires out of both ends any one have any ideas

 

if you are getting pressure back through the air box and exhaust on a single combustion either your timing is way out which i doubt or your valve shim is tight and valves arnt closed . which is more liley. do a compression check. bet you wont have much..
check clerances on valves if thats good might a damaged valve or seat , and or sticking / bent valve

 

Be sure to roll the motor over by hand upon reassembly - can you see what broke the decomp ?
Only thing I can think of is they installed something way wrong for the edge of the decomp to come in contact with the shim to break it off ... not even sure if that is possible ... hmm