deadchef
xsbobblehead
hi, first off great site, tons of great info and members!
'81, basically stock with 4100 miles with pods (not the ones that block air holes)
newly rebuilt petcock and cleaned out tank
new fuel lines & intake boots & spark plugs
cleaned carb and replaced float needle and bowl gaskets
adjusted float levels to spec (27mm)
tested the diaphragms with my thumbs over the air holes- all good there
all other seals seem to be in good shape
mix screw 3 turns out
issue: from idle to about 4k rpms the bike runs, pulls and idles fine. after about 4.5k the engine stumbles like it's running lean and it's difficult to get it much past 6.5k. changed the main jet from stock 132.5 to 135 and now 137.5 and still getting the same results without any real noticeable difference. i'm currently waiting for 140 mains to show up and test but i'm starting to wonder if they will make a difference. unfortunately i don't have the stock airbox or filters to use as a control test (actually i have them but they were the originals and they were disintegrating). the plugs don't tell me much since i haven't put many miles on them yet.
i have checked and adjusted cam chain tension and valves. all good.
basically just throwing it out there for another set of eyes to look over and suggest something i might be missing. and yes, i've read, studied and tattooed the carb guide to my arms.
thanks!
'81, basically stock with 4100 miles with pods (not the ones that block air holes)
newly rebuilt petcock and cleaned out tank
new fuel lines & intake boots & spark plugs
cleaned carb and replaced float needle and bowl gaskets
adjusted float levels to spec (27mm)
tested the diaphragms with my thumbs over the air holes- all good there
all other seals seem to be in good shape
mix screw 3 turns out
issue: from idle to about 4k rpms the bike runs, pulls and idles fine. after about 4.5k the engine stumbles like it's running lean and it's difficult to get it much past 6.5k. changed the main jet from stock 132.5 to 135 and now 137.5 and still getting the same results without any real noticeable difference. i'm currently waiting for 140 mains to show up and test but i'm starting to wonder if they will make a difference. unfortunately i don't have the stock airbox or filters to use as a control test (actually i have them but they were the originals and they were disintegrating). the plugs don't tell me much since i haven't put many miles on them yet.
i have checked and adjusted cam chain tension and valves. all good.
basically just throwing it out there for another set of eyes to look over and suggest something i might be missing. and yes, i've read, studied and tattooed the carb guide to my arms.
thanks!