Dukegonzo
XS650 New Member
Howdy All.
1981 XS650 Chopper. Hugh’s Handbuilt CDI PMA ignition - dual Minuni VM 32’s.
Having a hard time tuning the carbs.
Velocity stack air cleaner - basically open.
Very minor baffled exhaust.
Pilot Jet - 22.5 - (2 turns out)
or 20 (1 turn out)
Needle Jet - P4
Needle - 6DH7
Slide - 3.0
Main - 170
The bike will idle fine - but dies if you give it any throttle. Initially I was fighting a flat line for most of the mid range section. On hand I have a bag of pilot jets from 15-50. 20 is a bit lean 22.5 is a bit rich (all based off air mixture screws turns) but I’ve settled on 22.5 for now.
I have a variety of needles including 6F4 & 6F5 as well as Needle Jets to address the flat mid range. Including P2 P4 P5 & Q2.
Like I said above - I’m either fighting a flat mid range or I’m fighting a bike that sputters and dies under the slightest throttle above idle.
Any suggestions on tuning configurations would be greatly appreciated seeing as there’s not much out there for VM32’s on 650’s and instead VM34’s.
1981 XS650 Chopper. Hugh’s Handbuilt CDI PMA ignition - dual Minuni VM 32’s.
Having a hard time tuning the carbs.
Velocity stack air cleaner - basically open.
Very minor baffled exhaust.
Pilot Jet - 22.5 - (2 turns out)
or 20 (1 turn out)
Needle Jet - P4
Needle - 6DH7
Slide - 3.0
Main - 170
The bike will idle fine - but dies if you give it any throttle. Initially I was fighting a flat line for most of the mid range section. On hand I have a bag of pilot jets from 15-50. 20 is a bit lean 22.5 is a bit rich (all based off air mixture screws turns) but I’ve settled on 22.5 for now.
I have a variety of needles including 6F4 & 6F5 as well as Needle Jets to address the flat mid range. Including P2 P4 P5 & Q2.
Like I said above - I’m either fighting a flat mid range or I’m fighting a bike that sputters and dies under the slightest throttle above idle.
Any suggestions on tuning configurations would be greatly appreciated seeing as there’s not much out there for VM32’s on 650’s and instead VM34’s.
