lumberjack
XS650 Member
I bought a 1979 XS650 special from a local fellow, bike has some goodies in it (PMA kit, new clutch etc). He installed the XS performance pod filters, and gutted the factory mufflers (end caps are on there, but I removed them today... seems to have run a tad better)
Anyway, I know I will need to rejet, because his claimed "jetting" seems off. (even though he rebuilt the carbs)
Here's the setup:
Stock bore/engine Xs650
BS38's
XS pods
Factory gutted pipes (may as well say straight pipes, at this point)
I haven't had a chance to rip open the carbs fully, but I know the MAIN's are 140s
My issue:
- It used to idle just fine on choke (it would hold high RPM, then run and idle fine). Suddenly, the choke does nothing really, and the bike will actually run better with the choke off, right off cold (about 30 seconds after start, actually)
- I have moments where it runs better on the choke, but will die if I come to an idle stop. (so acceleration is great on choke, but stop light? dead, turn choke off or risk kicking it in traffic).
- From idle to about 3K rpm, it's a slow steady roll on, but lacks MAJOR kick.. just feels WEAK.
- From 3-5K I get a (often enough) spurts and sneezes, occasional coughs and cut outs.
(you know the bike is trying to pull * wheezes* keeps pulling etc)
- From 5500 to redline, pulls like a beast. which leads me to believe the MAINS are FINE. I think!
- LOTS of POP POP POP backfire on downshift and quite a bit on Decel.
- The left carb is smoking at stop lights, once the bike is running hot (fully warmed up); There is smoke coming out of the filter...
- There is some sort of "leak" on the left carb, that I can't pinpoint. Essentially, if it's running, and I put my bare hand beside the carb, I can feel a slight pulsating leak, as though someone was intermittently blowing on my hand - Not sure what it is, but I can't find it. Carb was rebuilt, maybe something isn't tight. The leak is definitely up TOP (towards the diaphragm cover plate, petcock side of the carb)
What I would also like:
WHAT ARE YOUR SPECS!
Seriously, if anyone is running pod filters and straight pipes, what does your jetting/needle clip position look like?
I feel that the needles are on the wrong clip and the pilot is wrong, for my bike. Mains seem OK, based on high rpm performance.
Any advice?
THANKS!
PS if anyone wants to donate some VM34's to a poor kid, I'll take them haha (jokes)
Anyway, I know I will need to rejet, because his claimed "jetting" seems off. (even though he rebuilt the carbs)
Here's the setup:
Stock bore/engine Xs650
BS38's
XS pods
Factory gutted pipes (may as well say straight pipes, at this point)
I haven't had a chance to rip open the carbs fully, but I know the MAIN's are 140s
My issue:
- It used to idle just fine on choke (it would hold high RPM, then run and idle fine). Suddenly, the choke does nothing really, and the bike will actually run better with the choke off, right off cold (about 30 seconds after start, actually)
- I have moments where it runs better on the choke, but will die if I come to an idle stop. (so acceleration is great on choke, but stop light? dead, turn choke off or risk kicking it in traffic).
- From idle to about 3K rpm, it's a slow steady roll on, but lacks MAJOR kick.. just feels WEAK.
- From 3-5K I get a (often enough) spurts and sneezes, occasional coughs and cut outs.
(you know the bike is trying to pull * wheezes* keeps pulling etc)
- From 5500 to redline, pulls like a beast. which leads me to believe the MAINS are FINE. I think!
- LOTS of POP POP POP backfire on downshift and quite a bit on Decel.
- The left carb is smoking at stop lights, once the bike is running hot (fully warmed up); There is smoke coming out of the filter...
- There is some sort of "leak" on the left carb, that I can't pinpoint. Essentially, if it's running, and I put my bare hand beside the carb, I can feel a slight pulsating leak, as though someone was intermittently blowing on my hand - Not sure what it is, but I can't find it. Carb was rebuilt, maybe something isn't tight. The leak is definitely up TOP (towards the diaphragm cover plate, petcock side of the carb)
What I would also like:
WHAT ARE YOUR SPECS!
Seriously, if anyone is running pod filters and straight pipes, what does your jetting/needle clip position look like?
I feel that the needles are on the wrong clip and the pilot is wrong, for my bike. Mains seem OK, based on high rpm performance.
Any advice?
THANKS!
PS if anyone wants to donate some VM34's to a poor kid, I'll take them haha (jokes)