SuzukiSavage.com - Main jet - carb on or off? Results!

barry68v10 Serious Thumper Offline Posts: 955 Maryland Gender:	Main jet - carb on or off? Results! 06/21/08 at 10:15:26 I'm swapping main jets today and was wondering whether this is better done with the carb on and just drop the bowl, or carb off. Anyone tried both? I'm assuming I'll have to replace the bowl screws either way...
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verslagen1 YaBB Moderator ModSquad Offline Where there's a will, I want to be in it. Posts: 28884 L.A. California Gender:	Re: Main jet - carb on or off? Reply #1 - 06/21/08 at 10:20:25 Give it try on the bike, as you said you're replacing the screws anyway. As you might have guessed the hard part is breaking loose the screws, since you'll be replacing them, just grab 'em with a vise grips and twist away. Then loosen the clamps and turn the carb to the side to make it a little easier.
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Reelthing

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Re: Main jet - carb on or off?
Reply #2 - 06/21/08 at 10:23:06

once the screws are replaced with the s/s allen heads it's a matter 5 minutes to swap the mainjet - just drain, drop the bowl, push back on the battery box a little and off it comes - the first time the screws are broken loose is the trick - takes a lot of pressure to keep from strip'n the soft thread locked screws - use new bit with enough pressure to almost lift the bike and toss those screws in the trash

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justin_o_guy2 Serious Thumper Offline What happened? Posts: 55279 East Texas, 1/2 dallas/la.	Re: Main jet - carb on or off? Reply #3 - 06/21/08 at 13:11:41 Mine are still stock, been off & back on??> How many times?? I Have the SS replacements, just havent had reason to install, YET.. The stockers are anti-siezed & tight, so,, why mess?
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Re: Main jet - carb on or off?
Reply #4 - 06/22/08 at 06:32:58

If you still have stock screws it will be SO much easier to get them off with the carb off and a impact screwdriver. Just go ahead and replace ALL of the screws when you have it off that way you don't have to take the carb off again. Now I can do needle mods, and change jets with the carb still on the bike and all I have to take off is the seat and tank. Which on my bike the tank comes off really easy thankfully.

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barry68v10

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Re: Main jet - carb on or off? Results!
Reply #5 - 06/23/08 at 19:47:04

Ok. Rejetted with the carb on connected to everything. Re-used the stock screws since they were in great shape and didn't see any need to change them now.

With a 150 main, and no white spacer, Suzi's running SWEEEET!

Again, with a little LONGER, higher volume exhaust and much less backpressure, I found my idle had to be leaned significantly. (Idled far too rich immediately after the swap.) Anybody experience the same thing? What's so different about my setup than everybody else's? Undecided

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petc0ck mod, white spacer removed, 150 main jet, 12.5" shocks, 16" turnout muff, oil cooler mod, chain conversion, Tkat brace, external fuel filter, fuel screen removed...

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J Mac Senior Member Offline Laissez Les Bon Temps Roulez Posts: 407 Louisiana, USA Gender:	Re: Main jet - carb on or off? Results! Reply #6 - 06/23/08 at 20:05:40 How did you know it idled too rich? Black smoke? I thought reducing back pressure tended to lean out a system. Reel Thing?
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Sandy Koocanusa

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Re: Main jet - carb on or off? Results!
Reply #7 - 06/23/08 at 20:09:29

I don't know what's different, but the more muffler guts I take out, the leaner mine runs. Put in a bigger pilot today. Hopefully that will get rid of the loud bangs so I can enjoy the loud roar.

I'm still confused on this jetting stuff. Mine had a 155 main jet stock. Everyone else goes up to a 150 and is happy. I don't get it. I guess as long as it runs, I don't have to get it.

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verslagen1

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Re: Main jet - carb on or off? Results!
Reply #8 - 06/23/08 at 21:22:50

J Mac wrote on 06/23/08 at 20:05:40:

How did you know it idled too rich? Black smoke? I thought reducing back pressure tended to lean out a system. Reel Thing?

Depends on the muffler (among other things), that's why no one can tell you exactly what jets and how manys turns out. I think the later HD muffs have probably been tuned to be quiet and have some back pressure. (epa)

I put a supertrapp on and it poofs on shut down ever so softly. Cracks me up so I leave it. Did experiment with it, and now it poofs regardless of the pilot setting, but no bang. Dam I miss that. :'(

With the stock muff I did exactly to lancers guide and got a pow on shut down. gave it about a 1/4 turn rich and it was my typical poof. Grin

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Reelthing

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Re: Main jet - carb on or off? Results!
Reply #9 - 06/23/08 at 22:40:41

barry68v10 wrote on 06/23/08 at 19:47:04:

Ok. Rejetted with the carb on connected to everything. Re-used the stock screws since they were in great shape and didn't see any need to change them now.

With a 150 main, and no white spacer, Suzi's running SWEEEET!

Again, with a little LONGER, higher volume exhaust and much less backpressure, I found my idle had to be leaned significantly. (Idled far too rich immediately after the swap.) Anybody experience the same thing? What's so different about my setup than everybody else's? Undecided

if I remember correct your at sealevel right? - so you have stock pilot, a 150 mainjet, NO white spacer at all, and where are you on turns out from a soft seat of the mixture screw?

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barry68v10 Serious Thumper Offline Posts: 955 Maryland Gender:	Re: Main jet - carb on or off? Results! Reply #10 - 06/24/08 at 14:30:08 Yes, I'm at sea-level. I was at 2.75 turns out with stock muffler, now I'm at 1.5 turns out. Changing the main jet didn't affect idle mixture despite what the factory Mikuni manual says.
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Reelthing Serious Thumper Alliance Member Offline Fish or ride that is the question Posts: 5397 Houston,Tx Gender:	Re: Main jet - carb on or off? Results! Reply #11 - 06/24/08 at 21:13:29 Why it was running correct before with the mixture out to 2 3/4 turns and a stock muffler is strange - the 1.5-2.0 sounds right on
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