JNaw
XS650 Enthusiast
Hey all, got the bike up and running and been enjoying the good weather this year so far. Still tinkering with the jetting as I can't get it quite dialed in, just want to share what's going on and brainstorm with you guys
79 xs650 special (non special gastank, dual fed peacocks/carbs/non vacuum, new carb holders)
Jet specs: (3428ft elevation),
145 main
Middle clip on needle (3 from bottom)
32.5 pilots (too big I think but working on it)
Passes the diaphragm test.
Canadian spec bike
Synced best as I can as I don't have access to a vacuum source, just used the "hands over the pipes", as well as dead cylinder method.
Mods:
Uni pods
Emgo tapered mufflers
New ignition coils/plugs/battery/stator (plugs gapped correctly last year)
1. Engines bogging/cutting out/running out of fuel at highway full throttle runs up hill, opening gas cap seems to help/mostly eliminate it. Is there a procedure to enlarging the venting hole in the gas cap?
2. Ties in with 1, full throttle runs there is a minor surge (not the bogging but just a slight power surge) Im having a hard time thinking it would be lean with 145's, could this be a symptom of too rich? (I'm going to try 142.5 mains if I can't get my hands on them, as bike seems to have slightly more power when cold, but very minor difference)
3. I've got 2.5 turns out mixture screw on one carb, and 1 turn out on the other, with the same jets, no noticeable vacuum leak with spraying brake clean all over the carbs while running, what gives?
Im going to try cleaning the carbs and filters again and see if that changes anything, but sort of stuck in my thoughts here. I have only tuned slide carbs so not super familiar with CV, although working through the tuning guide for CV's when Ive got time.
Let me know your thoughts and what I should try. Thanks all.
79 xs650 special (non special gastank, dual fed peacocks/carbs/non vacuum, new carb holders)
Jet specs: (3428ft elevation),
145 main
Middle clip on needle (3 from bottom)
32.5 pilots (too big I think but working on it)
Passes the diaphragm test.
Canadian spec bike
Synced best as I can as I don't have access to a vacuum source, just used the "hands over the pipes", as well as dead cylinder method.
Mods:
Uni pods
Emgo tapered mufflers
New ignition coils/plugs/battery/stator (plugs gapped correctly last year)
1. Engines bogging/cutting out/running out of fuel at highway full throttle runs up hill, opening gas cap seems to help/mostly eliminate it. Is there a procedure to enlarging the venting hole in the gas cap?
2. Ties in with 1, full throttle runs there is a minor surge (not the bogging but just a slight power surge) Im having a hard time thinking it would be lean with 145's, could this be a symptom of too rich? (I'm going to try 142.5 mains if I can't get my hands on them, as bike seems to have slightly more power when cold, but very minor difference)
3. I've got 2.5 turns out mixture screw on one carb, and 1 turn out on the other, with the same jets, no noticeable vacuum leak with spraying brake clean all over the carbs while running, what gives?
Im going to try cleaning the carbs and filters again and see if that changes anything, but sort of stuck in my thoughts here. I have only tuned slide carbs so not super familiar with CV, although working through the tuning guide for CV's when Ive got time.
Let me know your thoughts and what I should try. Thanks all.
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