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Discussion Starter #1
this is driving me crazy
i rejetted my carbs with the S$S chubby air system
http://www.sscustomcycle.com/products/engine/v-star1100.shtml/
i also added the cobra slip on drag pipes.
after installing this the bike never ran the same.
not much power when you get on it.
seems to bog at first then catches but when you get to like
70-75 and just cruise the bike seems to have less power and bike
pops through carb and backfires at time from exhaust.
so i took carbs off , cleaned and reset all the jets and air screw to
where it was suppose to be set.
still runs like crap
someone said i would need to sinc the carbs and that would help.
could this be a carb problem? maybee the jets and needle screw
shims i put in are incorrect.
i checked spark.thats good
fuel is good
????????????????????
at a loss

was going to buy the KJS manifold and carb kit
uses 1 carb they supply and new manifold.
http://www.kjsmotorcycleworks.com/kjs_manifold.htm

any ideas?
thanx for any suggestions.

baffled in RI
 

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Sounds like multiple problems. A little more info please. What Bike is it? Where are you having throttle problems. You say bogging then catches low what throttle position 1/4, 1/8, 1/2? Backfires through carb at higher RPMs. again what throttle position. What are your settings now? PMS, Primary Jet, Main Jet and Needle position (clip setting and washer quantity and which end you counted from if aftermarket needles).
 

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I had same problem and all I had to do was just tune the carb. I learned from a guy in town 47 + YRS experience. He told me rear carb 5 th notch down on needle. 4th notch on front. 112 jet on front cylinder carb and 110 on rear cylinder carb. 2 1/2 turn on front PMS Screw and 3- 3 1/2 turn on back Sync carbs. The home made kit costed me 7 dollars between Ace and walmart. No it works like a champ at any throttle, speed , or weight no pops, backfiring or any thing not even when you decel. any other questions my email is [email protected]. I don't know much about bikes but I do restore musclecars and a Carb is a Carb no matter if it is a 4 barrel or a single. It just takes time to get use to it and get a feel for it. Every bike is different even if they are the same model.
 

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Air leak

Saw a post where backfireing through carbs was air leak under the carbs. Check for air in and out of the carbs. Vacume under it. Sync is important also.

Dave
 

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Discussion Starter #6
ok
i took the carbs off and the main jets are 145
pilot jets are 22.5
each needle has one shim on the bottom of needle
none at top

pms is set to 2 and 1/2 turns both carbs

runs like crap
backfires mostly from rear cylinder exhaust
idles rough
not constant
revs up and down
engine gets very hot
np power
 

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I see you say it revs up and down. this is a very common symptom of a vacuum leak, which would cause it to run lean which would cause it to backfire through the carbs and cause it to feel gutless. Check your carb boots for a good seal and cracks. With the bike running spray some carb cleaner around your boots, if it runs different when you spray around them you have found your leak.
 

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Discussion Starter #8
thanks
i will check wed am

ill repost and let you know

do the jets seem to be the right ones?
 

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I've got pods similar to the chubby's anf I'm at 22.5/150, 2.75 turns and 2.8 washer thickness below plastic spacer. I'm using stock needles. Washer above clip is only for the spring to ride on and should be there. The adjustment washers are .5mm I have one of those and a #4 stainless washer that's mic'd at .9mm (washers are same od had to enlarge id to .120in.). What is your altitude? Have you changed elevation?
 

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Discussion Starter #10
well on mine i have one washer below on each needle and
none for the top
lost them on ground when rejetting
where can i get more washers
and are those washers that important for bike
to run smoothly?

im on east coast
mass
pretty much sea level
 

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The washers are important, just as important as the jets. you can get the washers at your local hardware store. Are you still using the plastic spacers, do you still have them? As I posted before you can use #4 stainless washers but you'll have to enlarge the center hole. Are you using the S&S needles? If so then you don't need the spacer washers as they are raised n lowered by the clip, but you still need the plastic spacer.
 
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