|
SuzukiSavage.com
/cgi-bin/YaBB.pl General Category >> Rubber Side Down! >> how do you know when air/fuel mix needs to be adju /cgi-bin/YaBB.pl?num=1267943783 Message started by RTC on 03/06/10 at 22:36:22 |
|
Title: how do you know when air/fuel mix needs to be adju Post by RTC on 03/06/10 at 22:36:22 ho do i know when i need to adjust the little screw behind the the brass or when i will need to rejet? right now i'm stock but the header is blue. altitude is a 3700ft. i"ll be adding a harley muffler soon and prob just fab an automotive air filter into the old screen soon as well. will exhaust wrap affect my mix/jetting as well? sorry i am new to this. i searched the forum extensively and read until my eyes hurt but there are so many variables. a good explanation would be helpful or just a "in this case" answer would be even better |
|
Title: Re: how do you know when air/fuel mix needs to be Post by verslagen1 on 03/06/10 at 22:44:26 Most easiest way is by the sound the bike makes on shut down. phfft [smiley=thumbsup.gif] no KERPOW :o yes Now a blue header means it's a little lean at your normal cruzin' rpm. Unless you cruze at idle you're gonna have to bump the main up a little. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by RTC on 03/06/10 at 22:47:29 i just found lancer's "simple carb tuning" post in the tech section and that pretty much explains it. but if anyone wants to add please feel free. also, any tips on getting to that screw mine has not been touched and is still covered. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by RTC on 03/06/10 at 22:49:16 vers... most times on shut down it gives one medium sized fart but sometimes it draws attention...a little louder. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by RTC on 03/06/10 at 22:51:38 another note..as i said i have not touched this screw yet and dont want to jack it up. when it starts giving noticable resistance should i stop or will it come to a definite bottom out? |
|
Title: Re: how do you know when air/fuel mix needs to be Post by Serowbot on 03/06/10 at 23:21:37 Danger!, danger!,.. No bottom!... The brass plug is about an 1/8" thick... and when you get through it, you will leap to the idle mix screw head and butcher it up... Use a sharp bit, and go very slow... the brass cuts like butter, and if you catch it right, the bit will snag and let you pull the plug out... Do not push... you will go past and mess up the head of the mix screw... as soon as you feel the bit start to bite, gently pull instead of push and the plug will usually draw right out... Slow, and easy does it... ;) |
|
Title: Re: how do you know when air/fuel mix needs to be Post by verslagen1 on 03/06/10 at 23:51:33 7B6E7663607D0F0 wrote:
You want to approach the stop very lightly, only your finger tips slowly twisting. When you come to a stop, you can test it more firmly. But if you're in a hurry giving it quick hard half twists, you'll get it in so hard it'll never come out. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by Routy on 03/07/10 at 05:49:29 I know I sound like a stuck record but..... maybe make sure it needs adjusting before you drill the plug. On my 07 I did the 1/2 spacer mod only, and I never had anything run so perfect. IMO, (and minimal exp) if it has a good idle, it don't need adjusting. If you are nitpickin at pops and sneezing at shutdown, I don't know if the air screw would change that. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by Charon on 03/07/10 at 05:54:47 If you are at 3700 feet above sea level, the mixture has "automatically" gone a bit richer because of the less dense air. There is a good chance you don't need to touch it at all. It's a little bit of a nuisance to pull the spark plug (make sure to blow the dirt out of the hole in which the plug lives before you remove it), but pulling the plug and looking at the electrode will probably tell you. If the plug electrode is a light tan, don't mess with it. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by RTC on 03/07/10 at 07:05:34 good info guys. i was thinking that because my pipe is blue i may be running lean though. i will be changing the spark plug next weekend so i'll check on it. the bike fire at shutdown is not too bad but engine braking in 2nd and third gear sounds pretty ridiculous i think....like four or five backfires each time unless i let off the throttle super slow. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by Charon on 03/07/10 at 07:13:35 The exhaust pipe doesn't know whether your bike is rich, lean, or just right. All it knows is that it has gotten hot. The pipe will progress from shiny chrome through a slight golden color to brown and blue, as it gets hotter. The stock pipe is double-walled, and the outer pipe which you see is separated by a small air space from the really hot inner pipe. Air flow from your forward progress helps cool the outer pipe to keep it from turning blue. At least one person on the Forum says he blued his pipe racking off the engine in the driveway, just listening to it. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by bill67 on 03/07/10 at 07:45:02 The inside of your muffler knows if your lean or rich,Black rich,Gray lean,Stick your finger in the muffler(When it not hot) and rub it around see what comes out on your finger. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by Routy on 03/07/10 at 07:52:16 Two (maybe 1) trips to the close by grocery store on a cold day will do that ! 414A4F4F1514230 wrote:
|
|
Title: Re: how do you know when air/fuel mix needs to be Post by Charon on 03/07/10 at 08:25:39 The only way to really "know" is by using an exhaust gas analyzer. Everything else is no more than guesswork or "rule of thumb." It is entirely possible, and in fact likely, that the mixture is lean at some settings and rich at others. For performance, it is very usual for the mixture to go rich at wide-open throttle. For economy the mixture needs to be leaner at cruise. When you add the EPA you get leaner mixtures for emission control. The mixture changes from day to day as the barometric pressure and the ambient temperature changes. The mixture changes with different fuels as the refiners switch from winter to summer blends. The best you can do is strike a happy medium where the settings is "pretty much right" most of the time. Unless you want to go to the extremes like racers, and rejet the carburetor for every day's ride. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by verslagen1 on 03/07/10 at 08:41:14 1500180D0E13610 wrote:
Check the header bolts and muffler clamp, you may have an air leak. |
|
Title: Re: how do you know when air/fuel mix needs to be Post by Serowbot on 03/07/10 at 09:52:56 A good indicator of overall jetting is the weather...if popping/backfiring increases on humid days, or at higher elevation, that indicates rich....less popping at those times indicates lean. To test the main, accelerate from 30 or 40 mph, in 4th or 5th gear at full throttle for several seconds, then reduce throttle by about 1/8,...if power increases for a second, you are lean on the main jet. Go up one jet size and test again. You can't jet perfectly for all situations,... what you're looking for, is a happy average... |
|
SuzukiSavage.com » Powered by YaBB 2.2! YaBB © 2000-2007. All Rights Reserved. |