Page 1 of 2 12 LastLast
Results 1 to 15 of 17

Thread: Any old-school mechs in CHCH?

  1. #1
    Join Date
    2nd August 2008 - 09:12
    Bike
    81 Sporty
    Location
    Christchurch
    Posts
    128

    Any old-school mechs in CHCH?

    Got an XS1100rh 81 model, had it in at the bike shop and got a compression test done as I thought something was up.
    Came back with the readings 200,20,25,250
    Ok so lets be thinking massive rebuild?
    Got work mech to test and readings came back 140,120,135,140. Ok so 2 and 3 something is up.
    Have rung several other places but they all seem to be scared of working on these old machines, so does anyone out there know of a good guy able to have a little look at it for me?

    cheers all

  2. #2
    Join Date
    20th January 2008 - 17:29
    Bike
    1972 Norton Commando
    Location
    Auckland NZ's Epicentre
    Posts
    3,554
    Quote Originally Posted by mdnzz View Post
    Got an XS1100rh 81 model, had it in at the bike shop and got a compression test done as I thought something was up.
    Came back with the readings 200,20,25,250
    Ok so lets be thinking massive rebuild?
    Got work mech to test and readings came back 140,120,135,140. Ok so 2 and 3 something is up.
    Have rung several other places but they all seem to be scared of working on these old machines, so does anyone out there know of a good guy able to have a little look at it for me?

    cheers all
    big difference between the two sets of readings...
    What brought you to take it in for a compression test?
    Was it missing? smoking? running rough?
    Could be valve clearances?
    give us internet wannabe mechanics some more info?
    in fact put up a post on the classic forum here!!!
    They are not that old school....some shops just don't want to work on old machines.
    I pulled down a Z1000 years ago..quite easy...just 4 125 motors on a common crank really.

  3. #3
    Join Date
    2nd August 2008 - 09:12
    Bike
    81 Sporty
    Location
    Christchurch
    Posts
    128
    ok for the wannabes then lol, took her in because she was ticking up the top end very noticibly. yep big difference in readings. have had her out for a run get to about 140 then it feels like it dont wanna go higher. yea yea I know I ride therefore I should know mechanical stuff, err no sorry came from working with people give me a body I'll fix that but a motor, err whats that little dohicky next to the thingymajig????

  4. #4
    Join Date
    20th January 2008 - 17:29
    Bike
    1972 Norton Commando
    Location
    Auckland NZ's Epicentre
    Posts
    3,554

    Yamaha

    repost on the classic forum as there is a guy called toycollector in ChCh and he has a couple of 4 cylinder older jap bikes, he might be able to point you in the direction of a frendly mechanic.
    I think there is even a guy who has had lots of xs 1100's.

    top end noises...hmmm
    with you getting two different sets of compression readings...maybe one with cold motor and other with hot...I'm thinking tight valves..
    but rattley top end sugests small ends of piston/rod or cam chain.
    If the bike can do 140kmph and the oil light is not coming on, I think its more likely top end and not tear down.
    cheers

  5. #5
    Join Date
    31st March 2003 - 13:09
    Bike
    CBR1000RR
    Location
    Koomeeeooo
    Posts
    5,559
    Blog Entries
    9
    Head gasket leak between cylinders 2 and 3...?
    $2,000 cash if you find a buyer for my house, kumeuhouseforsale@straightshooters.co.nz for details

  6. #6
    Join Date
    17th November 2008 - 10:08
    Bike
    SV650
    Location
    Ireland, for now
    Posts
    437
    Quote Originally Posted by ManDownUnder View Post
    Head gasket leak between cylinders 2 and 3...?
    Yep this would be my guess aswell.
    Not a major problem if it is, only a top end strip.
    K Ryan #119
    supported by
    Motodynamix, One tonne apparel, Pirelli, EBC brakes, AGV, Clover, RST, EK Chains, Repsol
    Thanks for your support

  7. #7
    Join Date
    19th October 2005 - 20:32
    Bike
    M109R, GS1200ss, RMX450Z, ZX-12R
    Location
    Near a river
    Posts
    4,308
    The 1st reading is and theoretically the bike would struggle to run if at all. The second reading is about average for a bike that age that hasn't had any major surgery to date and the variation isn't that extreme remembering #2 & #3 cylinders run hotter anyhow.
    Sounds like you need a good tune-up and if you want to go further a valve lap etc

    get a leak down test done to get a more precise finger on where #2 & #3 are loosing pressure

  8. #8
    Join Date
    14th July 2006 - 21:39
    Bike
    2015, Ducati Streetfighter
    Location
    Christchurch
    Posts
    9,081
    Blog Entries
    8
    Give Duane a call at Duanes Bikes & Skis 344 6069 unit 6/91 Waterloo Rd.

    He was at Norjos for years (worked there when I had new Kawas in the early 80's) so did his training on the old air cooled engines. Does work on Ducks as well.

    As far as parts go you'll find the aftermarket is your friend as factory bits will be hellishly expensive.

  9. #9
    Join Date
    2nd August 2008 - 09:12
    Bike
    81 Sporty
    Location
    Christchurch
    Posts
    128
    Quote Originally Posted by AllanB View Post
    Give Duane a call at Duanes Bikes & Skis 344 6069 unit 6/91 Waterloo Rd.

    He was at Norjos for years (worked there when I had new Kawas in the early 80's) so did his training on the old air cooled engines. Does work on Ducks as well.

    As far as parts go you'll find the aftermarket is your friend as factory bits will be hellishly expensive.

    Duane has worked on this bike for the previous owner and no 'hasn't the time' to work on it again, she's gettin old and bits have been broken here an there and modified over the top, but testimony to the ol girl she still wants to run

  10. #10
    Join Date
    1st January 2008 - 12:26
    Bike
    FZR
    Location
    Canterbury
    Posts
    114
    Quote Originally Posted by T.W.R View Post
    The 1st reading is and theoretically the bike would struggle to run if at all. The second reading is about average for a bike that age that hasn't had any major surgery to date and the variation isn't that extreme remembering #2 & #3 cylinders run hotter anyhow.
    Sounds like you need a good tune-up and if you want to go further a valve lap etc

    get a leak down test done to get a more precise finger on where #2 & #3 are loosing pressure

    I would say that the first reading the compression tester wasnt sealed in # 2 & 3 pot

    Easy test to see if its Rings or valves gaskets:
    Run the motor to normal operating temp
    Remove plugs do compression test (throttle wide open)
    Put a little bit of oil in each cylinder (couple of squirts with oil can)
    Spin the motor over a few times
    Redo compression test (throttle wide open)
    If the compression is a higher reading Rings if the same valves head gasket

    The second reading is not that bad
    We all die. But how many LIVE? "Shannon Noll"
    LIVE IT TO THE MAX

  11. #11
    Join Date
    2nd August 2008 - 09:12
    Bike
    81 Sporty
    Location
    Christchurch
    Posts
    128
    Quote Originally Posted by BBzz View Post
    I would say that the first reading the compression tester wasnt sealed in # 2 & 3 pot

    Easy test to see if its Rings or valves gaskets:
    Run the motor to normal operating temp
    Remove plugs do compression test (throttle wide open)
    Put a little bit of oil in each cylinder (couple of squirts with oil can)
    Spin the motor over a few times
    Redo compression test (throttle wide open)
    If the compression is a higher reading Rings if the same valves head gasket

    The second reading is not that bad

    Doing this is how we got the second readings.

  12. #12
    Join Date
    19th October 2005 - 20:32
    Bike
    M109R, GS1200ss, RMX450Z, ZX-12R
    Location
    Near a river
    Posts
    4,308
    Quote Originally Posted by BBzz View Post
    I would say that the first reading the compression tester wasnt sealed in # 2 & 3 pot
    Actually closer to the point would be to say the Compression tester was F@*KED giving a reading like that

    A healthy XS11 should read around the 170-190psi area

  13. #13
    Join Date
    2nd August 2008 - 09:12
    Bike
    81 Sporty
    Location
    Christchurch
    Posts
    128
    Quote Originally Posted by T.W.R View Post
    Actually closer to the point would be to say the Compression tester was F@*KED giving a reading like that

    A healthy XS11 should read around the 170-190psi area

    Yes but this also has been kitted out to a 1197 so would expect compression slightly above that perhaps?
    Also, the bottom gasket is twice the size of normal, was told this was because originally the compression was so much that the startor had trouble turning it over, also note no kick start fo same reason

  14. #14
    Join Date
    19th October 2005 - 20:32
    Bike
    M109R, GS1200ss, RMX450Z, ZX-12R
    Location
    Near a river
    Posts
    4,308
    Quote Originally Posted by mdnzz View Post
    Yes but this also has been kitted out to a 1197 so would expect compression slightly above that perhaps?
    Also, the bottom gasket is twice the size of normal, was told this was because originally the compression was so much that the startor had trouble turning it over, also note no kick start fo same reason
    1.1 sports didn't have a kick start fitted as stock.

    unless the big-bore kit included high dome pistons, that and the base gasket would equalise each other out so there wouldn't be a substantial change

  15. #15
    Join Date
    15th February 2005 - 15:34
    Bike
    Katanasaurus Rex
    Location
    The Gates of Delirium
    Posts
    9,015
    Excessive inlet valve clearance (ticking top end?) can also give a slightly lower compression reading. The valve opens later and closes earlier thereby letting less air/fuel into the cylinder which won't compress to the same pressure as a normal lungful.

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
  •