Suggested jets after a header install?

[Sojourner]

Ok, one more newb question for the day.

The PO put on a 4-to-1 and my bike runs lean. How lean? I have to leave the choke pulled out ~1/3" to 1/2" even after it's warm else it stalls out. Seeing as how I am trying to address the niggling issues to where I can get a decent baseline to build from, I need to address the jets. What would the next jump be in jet sizes from stock for a header? Size change for both the main and the pilot?

[Sojourner]

I found a Vance & Hynes doc (scanned into a PDF) on BassCliff's site. According to V&H I need to increase both- Main to 122.5 and the pilot to 47.5.

This sound like a good place to start? I have NO idea who made the header that came on the bike.

[salty_monk]

If you post pics someone will be able to identify it. Do you have Pods on the bike or stock airbox? If it's the one in your avatar then appears to be stock.
Did anyone mess with the airbox?
Are the Airbox boots well sealed? Have you changed the inlet side O'rings (if your bike has them, can't remember if it does or not). If it doesn't have the intake boot O rings, is everything well sealed on the inlet side?

You will probably find you need to go up by 2.5 - 5.00 on the main jet but you will not need bigger pilots unless you have Pods you can just wind out the pilot screws to 2.5-3 turns out.

You will also have to shim the needles a little. Radioshack sell the correct size washers.

Do you know these carbs are clean & have good O-rings & the correct float levels?

Having to keep the choke out could also mean that your pilots are blocked (or partially blocked) or that you have an air leak.

First step if you haven't already is to completely disassemble, clean & rebuild the carbs replacing O rings etc along the way. Then replace the Intake O rings & make sure everything is well sealed on the intake side. Clean or put in a new filter, up the main jet sizes, wind out the pilot screws, raise the needles a notch using washers (as yours will not have notches) and try it...

Exhaust looks like a Vance & Hines to me. I ran one on my 1000G with stock airbox. Main jets went up by 2.5 & I wound the screws out to 2.5-3 turns (fastest idle method). I shimmed the needle to approximate 0.5 to 1 notch from memory. I was using a K&N inbox filter.

[Sojourner]

Stock airbox, although it's missing the big squarish plastic cover that gets screwed in to cover the hole the air filter goes in.

As for clean carbs... HA. I just ordered new o rings from cycleorings.com and plan on a full disassembly and dunking. I figured I'd buy the new jets and install them when I put it all back together.

I think I broke newb mistake #11 or whatever. Bought a cheap bike with a boatload of problems. That's alright though, I grew up taking things apart to see how they work. You should have seen our toasters when I was a kid...

Here's a link to a bigger pic: http://www.thegsresources.com/_forum...ictureid=11261

[GateKeeper]

you might want to have a read in this thread it might help you out, and closer to the end we get into jetting etc....

http://www.thegsresources.com/_forum/showthread.php?t=198304

.

[hampshirehog]

For just a pipe you won't need much and if you're having to pull the choke out there's something else wrong (the choke throws loads of fuel in on these bikes).

You'll need that airbox cover by the way - it makes quite a bit of difference. Also it's metal not plastic.