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Almost there........

Started by Riolongo, May 23, 2013, 10:02:35 PM

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Okay, so I've cleaned the carbs, replaced idle jets, new plugs, new fuel and air filter, cleaned gas tank, synced carbs and still have one small issue.  When I snap the throttle there is a slight bog.  When I checked the carb sync all four carbs were fine, between 8-10 Hg, the carb idle is set at 1000 rpm, carb #1 has the mixture screw out 2 turns, #2 is out 3 turns, #3 is out 3 turns and #4 is out 2 1/2 turns. Also, for reference when I changed the plugs all the old plugs were a light brown or tan in color, I believe that tells me the bike was running okay, not lean or rich, but not 100% sure.

Any suggestions or helpful hints?




turn your idle up a bit (1200/1500).  Then maybe also turn the mixture screws out a quarter to half turn.
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'92 Yamaha TDM850
'80 BMW R100S/Sidecar
'81 Yamaha IT250(H)
'77 Yamaha IT175(D)
'39 BSA WM20


Okay, so I turned #3 & #4 in 1/4 of a turn and that seemed to do the trick, idle is steady at 1000 and throttle response is much better.  Looks good for now, I'll ride a few miles and make further adjustments if needed.