TimBuz
XS400 Enthusiast
So I'm in the final stages of assembling my xs400 build and I've come to some carby issues. I've cleaned my stock bs34's and was in the process of re-jetting them to suit my pods and free flowing exhaust. The bikes been started and taken for a quick spin on stock jetting and its obviously running very lean. Anywho I took off the carbs and have realized that either I or the PO has snapped off a mixture screw in the carb body which I cant seem to get out. On top of this it seems there are no seals for the screws, my throttle shaft seals need to be replaced, the screws holding the butterflys to the shaft are also stuck fast and i cant seem to get them out for fear of stripping them, all the screws on the locating bracket have also been loctited and no amount of heat or acetone is working on them.
TL;DR I've bitten the bullet and bought a flashy pair of New VM30's. Based on info out there they seem to be about the right size for the bike.
I've searched high and low for tuning threads on these for xs400's, cb400's cb450's and kz400's and there is SOME info as to jetting specs but most threads seem to die off.
Anyway as a starting point I've found a jetting guide for a street tuned kz400 with pods and exhaust:
KZ400 tuning*** colder climate
**change supplied main from 250 to 230 (hex jets)
**change pilot from 40 to 27.5
**change throttle valve cutaway (slide) from 2.5 to 3.0
*Jet Needle : 6F5 on #4 (1 clip richer)
keep needle jet stock P-5
Keep air jet 2.0
I should have the carbs, new filters and throttle cable in the next few weeks and will continue with the thread once I start tuning.
How does that combo look for putting me in the ballpark for a reliable tune?
Cheers, Tim
TL;DR I've bitten the bullet and bought a flashy pair of New VM30's. Based on info out there they seem to be about the right size for the bike.
I've searched high and low for tuning threads on these for xs400's, cb400's cb450's and kz400's and there is SOME info as to jetting specs but most threads seem to die off.
Anyway as a starting point I've found a jetting guide for a street tuned kz400 with pods and exhaust:
KZ400 tuning*** colder climate
**change supplied main from 250 to 230 (hex jets)
**change pilot from 40 to 27.5
**change throttle valve cutaway (slide) from 2.5 to 3.0
*Jet Needle : 6F5 on #4 (1 clip richer)
keep needle jet stock P-5
Keep air jet 2.0
I should have the carbs, new filters and throttle cable in the next few weeks and will continue with the thread once I start tuning.
How does that combo look for putting me in the ballpark for a reliable tune?
Cheers, Tim