Author Topic: BS38 Mixture screw location?  (Read 46 times)

0 Members and 1 Guest are viewing this topic.

Offline Joffa1

  • Full Member
  • ***
  • Posts: 92
  • Karma: 0
    • Melbourne, VIC. Australia
BS38 Mixture screw location?
« on: November 29, 2019, 11:06:25 PM »
Simple one for you guys location of the mixture screw for the Mikuni BS38 carbs on an XS500C?

And setting it from scratch? Iím told screw clockwise until gently seated then out 1 and 1/2 to 2 turns and go from there?

Thanks for any help. Cheers.

Offline guylr

  • Administrator
  • Hero Member
  • *****
  • Posts: 1201
  • Karma: 19
    • ATL in the USA
Re: BS38 Mixture screw location?
« Reply #1 on: November 30, 2019, 04:04:16 AM »
Look straight in from the side of each carb near where they plug into the rubber manifolds. The screws will be on the top side facing out to you. Yours or may not still have the small nylon limiters that came on the mixture screws from the factory. If the do, carefully pry them off to do the adjustment of 1-1/4 + or - 1/2 turn out from lightly seated. If the limiters were still on there's a strong possibility the screws have never been out in which case the pilot fuel circuits are probably partially plugged up with stale fuel residue. If so the carbs should be removed and cleaned.

Guy
« Last Edit: November 30, 2019, 04:07:20 AM by guylr »
Now Retired Yamaha guy. Cut me and I bleed "Cinquasia Red"

Offline Joffa1

  • Full Member
  • ***
  • Posts: 92
  • Karma: 0
    • Melbourne, VIC. Australia
Re: BS38 Mixture screw location?
« Reply #2 on: November 30, 2019, 05:21:26 AM »
Thanks so much for the info Guy! I had assumed that was the screw but the little nylon limiter was confusing me as I didnít think it would allow for enough range of adjustment and it wasnít something I saw mentioned in any literature. Youíve made it much clearer for me!

I thought I had been pretty thorough with my carb clean but possibly not if I didnít have this screw out when cleaning?