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

Help Bandit 250 problem.

Discussion in 'Suzuki 250cc In-line 4's' started by Alibongobingo, Mar 18, 2018.

  1. Wozza

    Wozza Active Member

    Messages:
    361
    Likes Received:
    190
    Trophy Points:
    148
    Joined:
    Mar 21, 2017
    Gender:
    Male
    Location:
    South Australia
    My Bike:
    GB250
    If you can hold a thumb or finger over the plug hole, at 30psi you should be able to hold it there as it turns over....
     
  2. Joker

    Joker If you want me find Club250 on facebook. Premium Member Contributing Member

    Messages:
    2,722
    Likes Received:
    1,385
    Trophy Points:
    798
    Joined:
    Feb 2, 2014
    Gender:
    Male
    Location:
    Melbourne
    My Bike:
    CBR600F2 x 2, FZR250, XV1100
    Mine had 3 at about 135-140PSI by memory and 1 at about 80 and it ran eventually albeit poorly and was a real pain.

    Either all your valve clearances are out, it's been overheated and all 4 rings have gone or you're reading it wrong/made a mistake in the setup. As has been said you want at least 115PSI on each.

    I'd start with the shims/clearances and compression test again before pulling the head and bore.
     
    • Like Like x 1
  3. Alibongobingo

    Alibongobingo Member

    Messages:
    25
    Likes Received:
    10
    Trophy Points:
    13
    Joined:
    Mar 18, 2018
    Gender:
    Male
    Location:
    Brisbane
    My Bike:
    Bandit 250. Kwaka zzr600
    ITS GOING. :)

    So I fabricated a leak down test by fitting the hose of the compression tester to a small compressor. I then put each cylinder in turn to a position with all valves shut and pumped her up on the compressor gauge and watched.

    Well I've nothing to compare to but the loss was very gradual from each and I could see/hear nothing from oil filler/ exhaust/inlet.

    So, given that... I checked the valve timing, which was good and shoved a feeler gauge under each cam lobe in the shut position which satisfied me. Mmm

    So then went off to the shop and got a new set of spark plugs and leads. I put the whole thing together again with the leads I fabricated (couldn't get the right ones for bike, so I got car ones and cut and screwed them in properly to the coils and plug sockets)

    Anyway... fresh fuel in the aux bottle, wated for carbs to fill, bit of choke and..

    VROOOM VROOM!

    I'm happy as a pig in sh%t.
    No idea where the 30psi compression test result came from.
    Now i can start making it run perfect.

    I'm sure this aint over yet.

    Al.
     
    • Like Like x 1
  4. kiffsta

    kiffsta Administrator Staff Member Dirty Wheel Club Contributing Member

    Messages:
    8,108
    Likes Received:
    5,931
    Trophy Points:
    1,168
    Joined:
    Aug 7, 2010
    Gender:
    Male
    Location:
    Brisbane
    Home Page:
    My Bike:
    90 CBR250RR ,Suzuki T500, 2005 GSF1200 Bandit and a 1972 t250j
    You bloody Beauty !!

    start ya bastard is evil, kills plugs quicker than looking at them
     
    Last edited: Mar 29, 2018
  5. Alibongobingo

    Alibongobingo Member

    Messages:
    25
    Likes Received:
    10
    Trophy Points:
    13
    Joined:
    Mar 18, 2018
    Gender:
    Male
    Location:
    Brisbane
    My Bike:
    Bandit 250. Kwaka zzr600
    Yep still being very odd. :/

    Starts fine and will sit there and idle all day and rev up sweet on the throttle. You can click into all gears on the main stand and it will rev up no problem and spin the wheel with no load (never, ever do this. I'm a trained idiot)

    However.... Any attempt to move the bike under its own power results in the revs cutting to 1500, where they will sit for maybe 2 minutes and if you don't have the throttle fully open it will stall.

    Then suddenly all revs are available again (out of gear) and it will idle and rev up no problem.
    Back in gear, try to go up the street again and...no...back to 1500rpm WOT.

    So same as original issue but after all that....

    Worse.

    F$ck me dead. Ive had enough.

    Lol
     
    • Funny Funny x 1
  6. ruckusman

    ruckusman Well-Known Member Premium Member Dirty Wheel Club

    Messages:
    1,653
    Likes Received:
    799
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    Guys this sounds remarkably similar to the FZR chugging issue with a bit of a twist

    Has anyone else been involved with both FZR and Bandit carbs and know of any similarities?
     
  7. kiffsta

    kiffsta Administrator Staff Member Dirty Wheel Club Contributing Member

    Messages:
    8,108
    Likes Received:
    5,931
    Trophy Points:
    1,168
    Joined:
    Aug 7, 2010
    Gender:
    Male
    Location:
    Brisbane
    Home Page:
    My Bike:
    90 CBR250RR ,Suzuki T500, 2005 GSF1200 Bandit and a 1972 t250j
    Very similar carbs
     
    • Informative Informative x 1
  8. ruckusman

    ruckusman Well-Known Member Premium Member Dirty Wheel Club

    Messages:
    1,653
    Likes Received:
    799
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    OK so where is Mr @GreyImport with his encyclopaedic knowledge and ready reference list to the best thread on FZR carbs, because there's just so god damn many of them :D :D :D
     
    • Like Like x 1
    • Funny Funny x 1
  9. GreyImport

    GreyImport Administrator Staff Member The Big Cheese Contributing Member

    Messages:
    8,551
    Likes Received:
    5,048
    Trophy Points:
    1,168
    Joined:
    Jun 14, 2012
    Gender:
    Male
    Occupation:
    Troublemaker
    Location:
    North by NW NSW Oztralia - Tamworth
    My Bike:
    *Kawasaki ZXR250C *Yamaha FZR250R 3LN1 *Suzuki GSX250 *Triumph Bonneville 750 T140V *Triumph Daytona 675
    <--- busy building bikes :minigun::fuckyou:
     
    • Funny Funny x 2
  10. Linkin

    Linkin The Apprentice Premium Member Dirty Wheel Club Contributing Member

    Messages:
    3,775
    Likes Received:
    2,199
    Trophy Points:
    943
    Joined:
    Mar 18, 2014
    Location:
    Sydney NSW
    My Bike:
    '99 YZF-R6, '99 GSF250VY
    Agreed.

    Pull out and inspect the needles and emulsion tubes from the carbs. Get the numbers if possible.

    From memory the FZR needles are 5CT7 and 5CT9
     
  11. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    What are the float height's set at ?
    And how many turn's out are the mixture screw's ?
     
    • Well said! Well said! x 1
  12. Alibongobingo

    Alibongobingo Member

    Messages:
    25
    Likes Received:
    10
    Trophy Points:
    13
    Joined:
    Mar 18, 2018
    Gender:
    Male
    Location:
    Brisbane
    My Bike:
    Bandit 250. Kwaka zzr600
    I've given up for today.

    I've still got it in my mind that this is electrical. It just feels it the way it just cuts to 1500rpm like that.. But why when I try to move forward? I'll have to have a good think.
    Not ruling out carbs though.
     
  13. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    The float height/fuel level is pretty critical in these carby's, if it's too high you will get a hesitation/stutter
    And if it's too low then it won't want to rev.

    If they are anything like the FZR's i've found they need the choke on a cold start, if it's starting without it then either the float is too high, or mixture's are too rich

    When you go to move forward this would make the float want to open a bit more and let more fuel into the fuel bowl.
     
    • Like Like x 1
  14. GreyImport

    GreyImport Administrator Staff Member The Big Cheese Contributing Member

    Messages:
    8,551
    Likes Received:
    5,048
    Trophy Points:
    1,168
    Joined:
    Jun 14, 2012
    Gender:
    Male
    Occupation:
    Troublemaker
    Location:
    North by NW NSW Oztralia - Tamworth
    My Bike:
    *Kawasaki ZXR250C *Yamaha FZR250R 3LN1 *Suzuki GSX250 *Triumph Bonneville 750 T140V *Triumph Daytona 675
    If its an old bike 99% of the time the problem will be the carbys

    If its an old bike with 2 carbys 99% of time the problem will be the carbys

    If its an old bike with 4 carbys the problem will be the carbys every time

    If I deleted every post and thread about inline 4 carbys ... there wouldnt much of the forum left



    :prankster: :thumb_ups:
     
    • Funny Funny x 3
  15. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    3,418
    Likes Received:
    2,344
    Trophy Points:
    923
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
    Didn't somebody have a bandit with the vent hoses on the carbs all going to the wrong place and that caused all kinds of weird issues?
     
    • Like Like x 1
  16. GreyImport

    GreyImport Administrator Staff Member The Big Cheese Contributing Member

    Messages:
    8,551
    Likes Received:
    5,048
    Trophy Points:
    1,168
    Joined:
    Jun 14, 2012
    Gender:
    Male
    Occupation:
    Troublemaker
    Location:
    North by NW NSW Oztralia - Tamworth
    My Bike:
    *Kawasaki ZXR250C *Yamaha FZR250R 3LN1 *Suzuki GSX250 *Triumph Bonneville 750 T140V *Triumph Daytona 675
  17. Alibongobingo

    Alibongobingo Member

    Messages:
    25
    Likes Received:
    10
    Trophy Points:
    13
    Joined:
    Mar 18, 2018
    Gender:
    Male
    Location:
    Brisbane
    My Bike:
    Bandit 250. Kwaka zzr600
    I have it plumbed in like the diagram, but i don't have the little tubes that go to the overflows (under bowls, 34 etc). Not needed though I reckon.
    I also don't have those breather hoses (12).
    Too high floats... maybe. This does make sense with the slight acceleration causing them to let a bit more fuel in. I've got an easy test for that perhaps. So we know it starts fine and will rev and idle all day until i try to move.. so I'll just gently push the bike up an incline whilst it is idling to lift the front. This can simulate acceleration. If it drops to the 1500rpm chugging then I'll redo the floats.....again! But lower.

    Must sleep.
     
    • Like Like x 1
  18. Bab

    Bab Active Member Premium Member Contributing Member

    Messages:
    108
    Likes Received:
    128
    Trophy Points:
    148
    Joined:
    Oct 2, 2017
    Gender:
    Male
    Location:
    Fergus, Ont. Canada
    My Bike:
    Suzuki GSF250p "Slingshot"
    I've been following your progress, and admit I don't have much help for you, but will confirm I also do not have the drain lines from the overflows.

    Is your vent tubes (12) kinked, or possible plugged? I discovered sunflower seeds in mine when I began the resurrection of my Slingshot.

    Perhaps someone can explain to me why in all the reading I've done throughout the forum about carbs no one has mentioned fuel being discharged from these overflows. The question being: if your floats are too high, should there not be fuel discharge from these ports? Are they indeed drains, or is their primary function just another way of venting the bowels, and in some instances have lines to direct fuel away in a controlled manner, incase of an overflow?

    As aggravating as it might be, keep at it, for the rewards are certainly worth it. This bike is a blast (sorry Eric B.)...
     
  19. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    If the fuel level is way too high,
    and say it's level with the top of the fuel bowl, a hose that is higher than the fuel bowl isn't going to overflow.
    The hoses from the bottom of the fuel bowl's are only drain's, so fuel can't get out the bowl till the drain screw is opened.
     
  20. Alibongobingo

    Alibongobingo Member

    Messages:
    25
    Likes Received:
    10
    Trophy Points:
    13
    Joined:
    Mar 18, 2018
    Gender:
    Male
    Location:
    Brisbane
    My Bike:
    Bandit 250. Kwaka zzr600
    Hey guys.. look

    Https://2fiftycc.com/index.php?threads/1990-gsf250-bandit-troubles.3568/

    (Hope that link works, just copied and past)
    So..it's not just me. This has happened to other bikes. They are describing the same thing.
    Shame there's no resolution :(

    My incline test produced no results. Lifting the front did not cause it to go into chug mode. Also it will now go into chug mode whenever it feels like it. Sometimes on pulling away, sometimes halfway down the street. It is so odd.

    15223742043701417324662.jpg
     

Share This Page