oldbaldguy Posted February 17, 2009 Share Posted February 17, 2009 At the risk of sounding like I just stepped off the short bus, could anyone help me with some carb issues? I have a 1975 XS650 with stock carbs (MIKUNI) removed airbox and installed pod filters, also fabbed exhaust pipes with a slight baffle. that being said, Will the bike be running rich or lean? and how do I adjust the carbs to make it run right? as it is now, it starts and idles fine but stumbles real bad on excelleration levels out ok at higher rpm's and the left side is popping like crazy on deceleration. i've removed and cleaned the carbs already... according to the manual (which is very vague or i'm really stupid) the air needle has 5 notches and my bike is set at the 4th from the factory should i move it up to the 3rd or down to the 5th... and should i try turning the mixture screw in or out? re-jetting is another topic the manual doesn't cover very well.. any thoughts on that topic? i've never screwed around with the carbs on my other bikes so i'm new at this please respond as if you were tutoring a total newbie, 'cause i am...thnx OBG Link to comment Share on other sites More sharing options...
grizzlydan Posted February 17, 2009 Share Posted February 17, 2009 OBG hello mate, if you have pod filters you may have to up grade the idle jets by 0.05 or 0.10 to get this bike working properly, depends on the exhaust that you have fitted. Link to comment Share on other sites More sharing options...
oldbaldguy Posted February 17, 2009 Author Share Posted February 17, 2009 OBG hello mate, if you have pod filters you may have to up grade the idle jets by 0.05 or 0.10 to get this bike working properly, depends on the exhaust that you have fitted. thanks grizzlydan...where the heck are the idle jets located? as i stated before the manual is really vague Link to comment Share on other sites More sharing options...
gabby Posted February 17, 2009 Share Posted February 17, 2009 oi tink der idle jets are the smaller of the two inside der float bowl . theres a big brass one the needle slides in and out of ooh er and theres a small brass one beside it thats the one i think. buy them off the sad demented tired kraut....here, he's pretty good and not the cheapest but the best selection of bits forra xs650. definately need bigger needles i'd say. more air in.. more gas out... more fuel required. it,ll be running lean, before you go buy needles try turning the mixture screw out a bit, its possible thar might be enuff and you could move the circlip on the main needle down a bit (TOWARDS THE POINTY END), sorry, shouting there, to let even more fuel in but then turn the idle screw out before you run it hold the revs onb der throttle and adjust it back in till its tickin over nice i think. Link to comment Share on other sites More sharing options...
gabby Posted February 17, 2009 Share Posted February 17, 2009 ahh meant to say... the popping your getting under deceleration is usually associated with air getting in through the carb inlet rubbers,, personally i quite like the sound of it but if yer dont then when you put the carbs on make sure there good and tight that should sort it maybe,, ahh the sweet sound of decelerated backfire, ye cannae beat it man Link to comment Share on other sites More sharing options...
Moderator drewpy Posted February 17, 2009 Moderator Share Posted February 17, 2009 pod filters do tend to mask the vacuum and mess with the carb diaphrams. on my project I retained the carb to air filter rubber to eliminate this problem Link to comment Share on other sites More sharing options...
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