1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Project GSX250 restoration

Discussion in 'Your 250cc Projects' started by SwarleyAUS, Mar 21, 2017.

  1. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    5,102
    Likes Received:
    3,472
    Trophy Points:
    1,148
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
  2. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    Right so I do have to do a plug chop. Ok well I replaced the main because it wouldn't rev above 5k so now that issue is fixed I probably need not investigate any further then, as I'm not going to getting anywhere near the redline in practical use.

    You read them at the base of the porcelain? That's at odds with what's described at the website you linked isn't it?

    Ultimately, can anyone help surmise from those plugs whether I am really lean or just slightly lean at idle? The discolouration of the thread base would have be believe the mixture is ok, but there's no soot on the threads where there is on the porcelain so I'm kind of confused.
     
  3. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    5,102
    Likes Received:
    3,472
    Trophy Points:
    1,148
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
    • Agree Agree x 1
    • Informative Informative x 1
  4. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
  5. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    5,102
    Likes Received:
    3,472
    Trophy Points:
    1,148
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
    and I was going by your statement
    "Ok so brand new plugs and the result after a couple of power runs to 7k:"
    So I assumed you were tuning for main jet. We just had crossed wires. :)

    It is very difficult to tune CV carbs for pod filters. Please read this.
    http://www.litetek.co/docs/InSearchOfFreeLunch.pdf
     
    • Like Like x 1
  6. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    Right, yes, for mains alone you read the base of the porcelain, we agree on that! I was then seeking some help with determining if the idle circuit was lean/rich/okay. It was painful (in terms of noise levels and emotionally) to rev her to 7k alone so I definitely won't be running off the mains very often I don't expect!

    Yeah I understand, but it's not impossible - I'm not seeking perfection. Just don't want to run so lean as I damage the engine.
     
  7. Wozza

    Wozza Active Member

    Messages:
    361
    Likes Received:
    191
    Trophy Points:
    148
    Joined:
    Mar 21, 2017
    Gender:
    Male
    Location:
    South Australia
    My Bike:
    GB250
    dont worry to much about the idle circuit...really cant hurt if its a little lean or rich..its the high load/rpm lean runs that hurt :)
    If the bike idles evenly and is not hunting(rich) or dyeing when you back of on the gas(lean) its should be close...The engine is just sipping the air at idle and carbs are so insufficient (especially when old)anyways
     
    • Like Like x 1
  8. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,313
    Likes Received:
    2,383
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    So the main's sound ok,
    Just make sure the mixture screw's are set up right with no hesitation/stumble off idle,
    as that can make thing's scary when you're taking off in front of a car or merging in traffic and the bike doesn't want to move
     
    • Like Like x 1
  9. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    Thanks all, I think I'm 99% there with the setup now then!
     
    • Like Like x 1
  10. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    Hi guys, now I've had the bike running ok for a while I'm putting more time into restoring her... cleaning up the frame, new seat, fixing wiring, more painting, etc.

    Currently rebuilding the carbs and I've found I seem to be missing some o-rings. The manual shows an o-ring on the silver cylinder thingo (4) which both my carbs lack:

    Manual:
    upload_2018-10-21_21-32-35.png

    My carbs:
    44458575_302399490356159_5112907370430726144_n.jpg

    I can't find it these o-rings depicted on any drawings though. Am I indeed missing required o-rings? If so can anyone help me with a part number? Thanks!

    PS: I found my engine oil was full of fuel hence the carb rebuild =/
     
  11. Frankster

    Frankster Grey Pride...Adventure before Dementia Staff Member Premium Member Ride and Events Crew

    Messages:
    3,980
    Likes Received:
    2,208
    Trophy Points:
    923
    Joined:
    Nov 19, 2013
    Gender:
    Male
    Occupation:
    Gardener
    Location:
    Tasmania
    Home Page:
    My Bike:
    Spada, VT250F & ZX2R
    What does the fuel bowl look like where the silver cylinder thingo lines up to?
     
  12. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    There's a bit of an impression on the gasket from when it has been pressed into place, against that hole. Can't see any residue from a previous o-ring on the gasket.

    Hmmm I wonder if it's part 22... I was looking at a different drawing which this wasn't present on
    upload_2018-10-21_23-18-59.png
     
  13. Frankster

    Frankster Grey Pride...Adventure before Dementia Staff Member Premium Member Ride and Events Crew

    Messages:
    3,980
    Likes Received:
    2,208
    Trophy Points:
    923
    Joined:
    Nov 19, 2013
    Gender:
    Male
    Occupation:
    Gardener
    Location:
    Tasmania
    Home Page:
    My Bike:
    Spada, VT250F & ZX2R
    Yes, it's 22, but more importantly, what is the point of that O-ring? What's that area linked to that it requires an O-ring to seal it?
     
    • Like Like x 2
  14. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    If I take out the silver cylinder the hole runs straight into the venturi (venturi?) - the main air tube through the carb. On the bowl is nothing!

    44526545_1876192032495889_6531022081700659200_n.jpg
     
  15. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,313
    Likes Received:
    2,383
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    That silver disc look's like a plug that cover's the pilot circuit port/s.
    There might be a hole that run's across the carby body to connect it to the pilot jet?
    On the inside of the carby bore are there any tiny hole's that line up with the silver plug on the bowl side?
    If this hole/s is slightly blocked with gum etc it's be hard to get the mixture screw set right, and will be slightly lean off idle
     
  16. Frankster

    Frankster Grey Pride...Adventure before Dementia Staff Member Premium Member Ride and Events Crew

    Messages:
    3,980
    Likes Received:
    2,208
    Trophy Points:
    923
    Joined:
    Nov 19, 2013
    Gender:
    Male
    Occupation:
    Gardener
    Location:
    Tasmania
    Home Page:
    My Bike:
    Spada, VT250F & ZX2R
    Looks like there may have been something there at some stage. It looks like it's squashed into the bowl.

    GSX.jpg
     
  17. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    Well I've ordered part 22, whether it makes a difference or not will be found out shortly. Dont think it could be causing a rich condition safe to say. Found my needle valve o-rings were leaking so gotta replace those too.
     
  18. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250
    Yeah looking at it again I see that now. Bike was running fine(ish) without it but will try a couple of 13374-35C00 anyway!
     
  19. GreyImport

    GreyImport Administrator Staff Member The Chief Contributing Member

    Messages:
    10,914
    Likes Received:
    6,709
    Trophy Points:
    1,168
    Joined:
    Jun 14, 2012
    Gender:
    Male
    Occupation:
    Between a Rock and a Hard Place
    Location:
    North by NW NSW Oztralia - Tamworth
    My Bike:
    *Kawasaki ZXR250C *Yamaha FZR250R 3LN1 *Yamaha FZR400 *Triumph Bonneville 750 T140V *Triumph Daytona 675 *Triumph Tiger 800XC
    IMGP1956 (Medium).jpeg IMGP1955 (Medium).jpeg
     
    • Like Like x 1
  20. SwarleyAUS

    SwarleyAUS Well-Known Member

    Messages:
    141
    Likes Received:
    64
    Trophy Points:
    213
    Joined:
    Mar 11, 2017
    Gender:
    Male
    Occupation:
    Engineer
    Location:
    Cheltenham, Melbourne
    My Bike:
    Suzuki GSX250

Share This Page