Snowmobile Repair: reverse problems, yamaha rx 1, yami

Question
I have a 2003 yamaha rx 1 and last year drove it in reverse with the parking brake on and now it makes a screeching,  grinding noise when i put it in reverse,  it also doesn't go in reverse any more.  Any suggestions  

Answer
Hello Scott,

  You have some work on your hands, but it's just time consuming mostly. What happened most probably, is that the reverse gear inside of the chain case got it's teeth stripped off, as they are very cheaply built in most sleds. Not sure if you know the steps in taking apart the chain case, but let me know if you need any help with that. Here is a diagram for all the parts: http://216.37.204.202/yamaha_oem/YamahaSnow.asp?Type=13&A=231&B=31  . Also, check the entire linkage to make sure it didn't get bent or broken. Good luck with the Yami! Let me know if I can answer any other questions you might have! --Arcticatman