swrsmik
Active Member
I sometimes get a cough thru carb off idle when warm,and a stumble just before vboost come in that gets worse when warm.carbs are clean and balanced.any thoughts,thanks
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fmcandrew
Well-Known Member
Could be electrical...start with new plugs and then check the coils for cracks (if you still have the origionals)...the "gets worse when warm" comment would point me in the electrical side of the cumbustion process.
swrsmik
Active Member
True,its nice when you get a bike that you know what's been done or done right for that matter.it was running on one or two when I got it.I cleaned carve twice & balanced three times.it pulls hard when cool like am riding.I get into lights & temp comes up & it goes to crap.only off idle and right before vboost comes in,its more noticable when you roll into it slow but the hotter it geyts the bigger the stumble gets.I have a 4into1 kerker,jetted?my last max had a stage 7 and would idle all day & perfect thru all rpms.this one is stubburn.
Note to self: update screen more often.........
If it runs better/good with the engine cool, but goes to crap after it warms up, I'd say you got the typical low voltage syndrome. Check your charging voltage AFTER WARM UP and WITH THE FAN ALREADY RUNNING. You should have over 13.25 volts, or there abouts. If your voltage drops low with the fan running, your CDI box will be throwing fits, and dropping a cylinder (or two) in the lower rpm range while idling.
If it runs better/good with the engine cool, but goes to crap after it warms up, I'd say you got the typical low voltage syndrome. Check your charging voltage AFTER WARM UP and WITH THE FAN ALREADY RUNNING. You should have over 13.25 volts, or there abouts. If your voltage drops low with the fan running, your CDI box will be throwing fits, and dropping a cylinder (or two) in the lower rpm range while idling.
swrsmik
Active Member
Not much history,just got it.has a kerker,not sure about jets.I checked voltage with fan but bike was cool(fan override)can't remember exact but over 13v.I leaned out a/f a good bit,helped idle a lot.the upper rpm stumble is more of the problem now.if I where to say slip clutch & crack wot,you would not notice it,it'll carry front wheel while spinning.today was near 100 outside and worse,in am when its 60ish,its near perfect.I got this cheap running on like 2 cylinders,sat awhile.I will try voltage when warm,check coils,and see what I come up with.my boots look rough,but don't seem cracked thru & I did spray them and seemed fine but they are on my list to replace.also,I see a lot of 3 spoke wheels,is there a swap or are they rehubed?
swrsmik
Active Member
Dumb question,how do you get your bike pic at your user name?when you reply,I see your bike.
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