Results 1 to 5 of 5

Thread: GN250 head repair?

  1. #1
    Join Date
    29th July 2015 - 07:28
    Bike
    1983 GN250
    Location
    Waiheke Island
    Posts
    1

    GN250 head repair?

    Hi everyone. I have a 1983 GN250 in pretty bad nick that im restoring/ modifying. The head and piston are damaged, im replacing the bore and piston but heads are hard to come by so im going to repair it.
    There are a few gouges and dents in the combustion chamber that i have ground out clean, no cracks anywhere. A couple are very close to the valve seats so i cant weld them without replacing the valve seats, which i would rather avoid. My current plan is to braze them using a product like hts2000, which melts at around 350 celcius and then grind and polish the chamber. Has anyone else done something similar to this? Any ideas what temperature the GN head gets to?
    Also, the head has been planed at some point in the past, does anyone know what the overall thickness of the head is stock? alternatively, what the volume of the combustion chamber is.

    Thanks for any help.

  2. #2
    Join Date
    27th February 2005 - 08:47
    Bike
    a red heap
    Location
    towel wronger
    Posts
    6,522
    its a gn250, it will go forever if you just put it back together and forget about the gouges.

  3. #3
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    12,179
    What he said.
    Don't sweat a few gouges unless its in the seats, But de-burr any shape edges.
    Slap in cam chain in it, lap in the valves, give it a bore then it will live for ever.



    Kinky is using a feather. Perverted is using the whole chicken

  4. #4
    Join Date
    17th June 2010 - 16:44
    Bike
    bandit
    Location
    Bay of Plenty
    Posts
    2,885
    There seem to be quite a few at the wreckers - and on tardme ...like this one

    http://www.trademe.co.nz/motors/moto...-925023391.htm

    Pasrts shouldn't be that hard to get shoudl they?

    If yiu habve the engineering skills then do what you are suggesting ..
    "So if you meet me, have some sympathy, have some courtesy, have some taste ..."

  5. #5
    Join Date
    28th May 2006 - 19:35
    Bike
    suzuki
    Location
    lower hutt
    Posts
    8,219
    you must be proud to have probably the most modern bike on waiheke island, and the internaughty too, well done you.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •