need guidance on carbs

EJ8TrapKing

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my xs is running a lil sluggish and need advice on it. the main jet is 145, pilot is stock 42.5.
do I need to go up one size for the pilot jet?
it has pods and cut straight pipe.
when I pull throttle it is sluggish. maybe lack of gas?:doh:
heres a video
 
What year is the bike?Also have you looked at the jetting guide?Normaly a good starting point with the setup you have is go up 2 sizes mains and sometimes 3.If you go 3 sizes on the mains the guide says to go up 1 size on the pilot also.
 
We have the same bike and the mains should have plugs not the pilot.The plugs are usualy black rubber but I improvised on mine.I made them out of the cap that covers ends of my syringes LOL.
 
I bet your issue is the straight pipes, with no back pressure tuning the carbs will be damn near impossible, I had straight pipes and I could not get the engine to pull over 5000 but after making an exhaust with a muffler problems were solved.
 
I have the same set-up
Pods and ego shorty's (straight with glass pack, but totally free flowing straight) and I'm at a 47.5 pilot screw, stock mains, idle mixture screws 4 1/2 turns out and it works great! Just rose it a couple hundred miles up the pch!
 
With my setup that has open pipes and pod filters the only thing I noticed that didnt feel right that at 5k rpm the engine is so loud I didnt want to take it over 5k cause it sounded like it was going to blow up.I put my crossover with open pipes back on 2 days ago which gave the bike a little more back pressure and made it much more quieter.I went for a ride yesterday and got up to 70mph and 68k rpm.Definately not as scary at riding at 60mph with open pipes.I have my fuel mix turns at 3.5 turns and everything seems to run fine.Its definately not as cold natured as it once was either.I can start the bike at half choke which it only needs to run a minute or two before I can close the choke off and then the bike will idle at 11k cold,once fully warmed it idles at 14k`s.To me I see no advantages of running the biike with open pipes except blowing a persons ear drums out if you so desire.
 
you all have been so helpful thank you. As I wait for my 45 and 47.5 pilot jets in the mail, I have cut pipes and I think thats most of the problem but my theory is when I jet the air pilot jet, it'll idle and throttle right, hopefully.
Right now I got 150 mains and 42.5 pilots, with 3-1/2 turns out. It throttles alot better.
I suspect if I go up a pilot size and adjust the pilot screw to 2 turns, It'll be smoother.
Correct me if i'm wrong.
 
here a picture of the pipes
 

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Yeah, since mine are straights there is some power probably lacking at 60-100% throttle so i will eventually go up one main jet size.
 
Richmond I just noticed your from La Jolla.I know the place very well or did anyways.I used to fish off that breakwall thats there when I was a little kid.I grew up in the San Diego area most of my child hood.
 
EJtrap when you get your pilots try the 45 first and adjust the fuel mix turns to 4 out from seated.run our bike about 50 miles if you can and check plugs, and post a pic.
 
OK. As of now she is running on 150 mains, 45 pilots, and 4 turns out from seated.
she back fires and has a thump sound.
Response is better but I think I might have to adjust my valves
Here's a video of how she sounds.


P.S. Do I need an exhaust? I was thinking of like a 6x2 straight pipe for bigger back pressure.
 
Sounds good trapking,that thumping you hear is from the low idle WHEN THE ENGINE IS COLD>.You may have to turn it up some so she idles a bit higher.My opinion is I have found that back pressure does help.Also make sure and let your bike fully warm up before making any adjustments to the idle.FROM the pic of your bike it didnt look like theres much of a seat except for turned upside down skate board:shrug:Take her out for a ride and see how she responds then check the color of your plugs,when you can get them tan color your there with your fuel air mix.You may have to keep making fine tune adjustments till you get her there.
 
Thank you so much for the quick response. I just got it legal and i'm definitely going to take her out and see how she does. One question though, when choke is fully pulled out it dies on me. What is the cause of this?
 
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