/ Register

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

Help Spada idle screw

Discussion in 'Honda 250cc Twins' started by spatbent, Feb 4, 2020.

Page 2 of 2
  1. spatbent

    spatbent Active Member

    Messages:
    13
    Likes Received:
    4
    Trophy Points:
    173
    Joined:
    Dec 14, 2019
    Gender:
    Male
    Location:
    Australia
    My Bike:
    1989 Spada
    I screwed both needles in at the same time and still got nothing.
    Then pulled the carbs again and checked the float levels. One was just under 7mm and the other 10mm, which I adjusted.
    Is there a trick to carb removal and reinstall? It feels a bit brutal jamming down on the rubbers even after lubing them.
    Bike's running great now.. no more hanging throttle since the vacuum test, but the idle is all over the place, as it was before.
    So I ordered an assorted box of teeny o rings from ebay for $12 to see if they'll fit in the carbs so the needles work.
    Should I be looking at the air cutoff valves? I haven't removed them so I don't know their condition.
     
    spatbent, Feb 10, 2020
    #21
  2. GreyImport

    GreyImport Administrator Staff Member The Chief Contributing Member

    Messages:
    10,929
    Likes Received:
    6,713
    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
    GreyImport, Feb 10, 2020
    #22
  3. Gizziracer

    Gizziracer Well-Known Member Contributing Member

    Messages:
    387
    Likes Received:
    251
    Trophy Points:
    273
    Joined:
    May 7, 2017
    Location:
    Sydney
    My Bike:
    Honda vt 250 spada
    Yep, check all the rubber bits, cut off valves, blow air through the airways, check large mainjet needle diaphrams,(through the top of the carb.. )
    Its also possible you have a leak in the rubber carb manifolds, Good idea to replace them. The trick in fitting is to work out if the carb outlets are too close together or too far apart.. Then loosen the screw that holds the 2 carbs together and adjust them as required to fit, either pulling them apart or pushing them together. Once adjusted, tighten the screw back up, being careful not to change the angle between the two carburettors, They should slide in without incident once the angle is correct.. Sadly they will possibly need to be re balanced after changing the distance between the throttle arm and the other carb. Forcing them in to place often damages the manifold lip and creates an air leak.. These little guys are a little complex at times. After working on motor guzzis where carbs can be removed in around 5 to 10 seconds,(sometimes removing themselves while backfiring:) I find the many challenges these little hondas often present fascinating..
     
    • Like Like x 1
    Gizziracer, Feb 10, 2020
    #23
  4. Gizziracer

    Gizziracer Well-Known Member Contributing Member

    Messages:
    387
    Likes Received:
    251
    Trophy Points:
    273
    Joined:
    May 7, 2017
    Location:
    Sydney
    My Bike:
    Honda vt 250 spada
    Its possible 2 of these are required,,,,, https://www.ebay.com.au/itm/Honda-V...epid=0&hash=item3ababb0075:g:jNMAAOSwsqdcDjrr

    Or , possibly,, these,,,,,,, https://www.ebay.com.au/itm/Carbure...MC20-1989-1990-New-Original-Part/264468657982

    If you have to keep throwing money at these carbs its quite possible to spend a couple of hundred dollars and still not have the solution.. I purchased a pair of these Chinese carbs as a diagnostic tool and they are visually identical to the original spada ones.. I find it kinda spooky but also totally fascinating,, They are identical in every visual sense and work perfectly..
     
    • Like Like x 1
    Gizziracer, Feb 10, 2020
    #24
  5. spatbent

    spatbent Active Member

    Messages:
    13
    Likes Received:
    4
    Trophy Points:
    173
    Joined:
    Dec 14, 2019
    Gender:
    Male
    Location:
    Australia
    My Bike:
    1989 Spada
    2020-02-18 003.jpg
    Well my box of teeny o rings arrived and they are teeny!
    Way too small to use on the mixture screw so I stuffed in the smallest o rings I had in the shed and the screws now sort of work.. the rpm's change marginally when screwed in or out one or two turns. Will die if screwed all the way in.
    I cleaned the carbs yesterday in an ultrasonic tank which didn't make any difference.
    It idles a lot better and the performance is great it's a fun bike to commute on that's for sure.
    And no more hanging throttle.
    I'm going to keep searching for the right-ish o rings... I don't want to buy the carb kits everything else seems fine.
    The pic shows the original o ring in the centre, the teeny one on the right, and the one that's in the carbs now on the left.
     
    • Like Like x 1
    spatbent, Feb 23, 2020
    #25
  6. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    5,107
    Likes Received:
    3,473
    Trophy Points:
    1,148
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
    maelstrom, Feb 23, 2020
    #26
  7. Gizziracer

    Gizziracer Well-Known Member Contributing Member

    Messages:
    387
    Likes Received:
    251
    Trophy Points:
    273
    Joined:
    May 7, 2017
    Location:
    Sydney
    My Bike:
    Honda vt 250 spada
    Great that it’s running better.. any bearing shop should be able to provide a range of small o rings for a few $... did you get the springs/tiny washers as well? These provide the pressure required to properly seal and stop the needles vibrating, rotating and changing settings..
     
    Gizziracer, Feb 23, 2020
    #27
Page 2 of 2

Share This Page