Whats up guys? My bike is getting some major upgrades; 49T vortex rear sprocket, Progressive springs, Jardine full Exhaust, K&N lunchbox, Dyno jet kit stage 1. I figures I should just do everything at once so I take apart the entire bike together. I've done alot of upgrades and fabrication to the bike already, so i'm pretty knowledgable. My original plan was to install everything myself, take the carbs out of the bike and bring them to the shop and have them install the dyno jet kit. After getting this far I'm looking at the jet kit like I can do this, is this being silly, I hate paying people to do things that i'm capable of though. I've looked at "the poor man's way" to install and i'm not sure about that, the carbs are out of the bike. Does anyone have a link to step by step insructions? Should I attempt this myself?
You can do it. Carburetors are painfully simple when you know how they work. (Just be sure you know how they work.) Rejetting is just replacing a thing with a hole with a thing with a bigger hole. The hard part is determining if the new hole is the right size or not. The carb tuning steps at Factory Pro are a good guideline.
http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html
The most important part is to start from tuning full throttle and work your way down. Or, if you're lucky, someone else has the same config and can hand you some numbers. (I had a lunch box filter and stock exhaust, and I just used some jetting numbers from Alpha, and it worked right away.)
If you're completely custom, you should expect to take the carbs off and try different things a few times. It's a good experience.
Scale of 1 to 5.I'd rate it a 3 for someone with no experience with mechanics.1.5 if you have mechanical ability and a general understanding of motorcycle carbs.
http://gstwin.com/rejet.htm
The only difference that I know of is 1 extra jet(mid main) and the throttle position sensor for the ignition control unit.
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting
http://cgi.stanford.edu/~sanjayd/gs500/Maintenance/ThrottlePositionSensorTPSAdjustment
I think I have the right settings to attempt first-
pilot 22.5
mid-main 65
main 147.5
Now i'm a little confused about the trottle position sensor, is this step neccessary?
Any more links for the procedure?
Thanx
Quote from: Chef GS500f 06 on May 29, 2008, 04:38:16 PM
I think I have the right settings to attempt first-
pilot 22.5
mid-main 65
main 147.5
Now i'm a little confused about the trottle position sensor, is this step neccessary?
Any more links for the procedure?
Thanx
Jetting sounds good.No the throttle position sensor doesn't have to be done.I posted that so you would know it's available if yours ever gets out of sync.That's all the good links I have.Poking around the Wiki and reading everything helps.Convinced me to buy to bikes and customize both of them. http://cgi.stanford.edu/~sanjayd/gs500/Main/HomePage
Thanks Alot, I should be ready to do it this weekend. Cool :cheers:
Quote from: Chef GS500f 06 on May 29, 2008, 04:56:11 PM
Thanks Alot, I should be ready to do it this weekend. Cool :cheers:
You're welcome.Any problems just post them.
Well now I got into the dyno kit and it tells me to use 128 pilot with k&N and full exhaust. The kit comes with 120 124 128 132 pilots. Should I just follow the dyno kit?
Please don't use a dyno kit.They are complicated and hard to tune.Not to mention you have to modify your carbs and it's very expensive to change them back.You can buy jets in pairs which is cheaper and easier to install.In most cases it's easier to tune.The jet kits numbers are different than Mikuni jets.Try the link below for Mikuni jets and ebay the jet kit.
http://www.motorcyclecarbs.com/Mikuni_Jetting_Components_C7.cfm
Alright I'll take your word for it, that's not the first time on this website i've heard the dyno jet kits were no good. I'll get the Mikuni jets, I felt like I was looking at two completely different set ups between the wiki and the dyno. Thanks again
Ben2go- do you think you could list everything that I would need to get from Mikuni? :cheers:
Quote from: Chef GS500f 06 on May 30, 2008, 03:34:13 PM
Ben2go- do you think you could list everything that I would need to get from Mikuni? :cheers:
You will need this from Mikuni
2 pilot jets=1 per carb
2 mid mains=1 per carb
2 mains=1 per carb
These you can get locally.
I'm not sure if the newer style carbs have more than 1 clip position on the needles.If not,you need 2 #4 washers.Any hardware store will have these.Get 4 that way you'll have extras in case you loose one, or when you clean the carbs later and there corroded.Ask for stainless but zinc or galvanized will work.You'll see the the needles and clips when you remove the black plastic tops off the carbs and pull the slides.
Read thru this a couple times and keep it handy when you start to use as a reference. http://gstwin.com/rejet.htm
Ok so I use the stock needles and clips? I'll get all the pilots from Mikuni, and what about the screw that I rotate 2,5 turns, use the stock as well?
Quote from: Chef GS500f 06 on May 30, 2008, 03:59:35 PM
Ok so I use the stock needles and clips? I'll get all the pilots from Mikuni, and what about the screw that I rotate 2,5 turns, use the stock as well?
Use the stock needles and clips.If it has more than 1 groove move the clip down to the next groove.If it only has one groove add a #4 washer between the clip and plastic spacer the clip sets on.All the jets should be Mikuni or Mikuni style.Yes 2.5 turns.If it runs a little lean try 3 turns and 3.5.
These links help explain tuning and rick/lean conditions.
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting-LeanOrRich?
Quote from: ben2go on May 30, 2008, 04:23:59 PM
Quote from: Chef GS500f 06 on May 30, 2008, 03:59:35 PM
Ok so I use the stock needles and clips? I'll get all the pilots from Mikuni, and what about the screw that I rotate 2,5 turns, use the stock as well?
Use the stock needles and clips.If it has more than 1 groove move the clip down to the next groove.If it only has one groove add a #4 washer between the clip and plastic spacer the clip sets on.All the jets should be Mikuni or Mikuni style.Yes 2.5 turns.If it runs a little lean try 3 turns and 3.5.
These links help explain tuning and rick/lean conditions.
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting-LeanOrRich?
+1
yes, the stock needles are much nicer than the dynojet needles. the re jetting matrix here on gstwins is a really nice place to start.
i did notice you're putting a 49 rear cog on ? are you proficient with wheelies ? you'll want to be before installing that ;)
good luck with the mods :)
Thanks for all the help, i'll keep you guys posted on the outcome, looks fun and interesting, i'm glad i'm attempting it myself.
Yeah i'm experienced with wheelies, but i'm thinking of going maybe a little smaller with the teeth number, i'm afraid i'm going to lose too much top end speed, i'm just trying to make it quicker and be able to do a good wheelie.
You're welcome and remember to be careful.The GS looses it's ability to pump oil thru the engine with the front end up in the air.
Another quick question, I got the air box out, there is 2 tubes that connect to the stock box, what should i do with these?? Thanx
Quote from: Chef GS500f 06 on June 01, 2008, 11:43:42 AM
Another quick question, I got the air box out, there is 2 tubes that connect to the stock box, what should i do with these?? Thanx
The one on the bottom of the box don't worry about.The one on the top,going to the valve cover, I used K&N filter 62-1320 and a brass barbed fitting from the hard ware store.Got all my filters from www.amazon.com .Here's a link to how it looks. http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/AirFilter It's on top of the K&N lunch box half way down the page.The part number is listed at the bottom as a breather cover filter.Is actually a pcv filter.pcv= positive crankcase ventilation Same as a car uses, except bikes don't use pcv valves.Be careful of some other ways to cover the fitting the hose runs to.You need to filter the air,thats why it was run to the air box.When the engine is cranking it pulls air in,when it's running it blows air out.Some oil will be lost thru the filter as mist.But not enough to make a difference.
Cool, got it. Ok ywo more questions and i think i'm good. I not sure which brass plug I need to drill to put idle screw in, what type screw do i get? Also, the washer order position- should it be washer,plastic ring,c-clip from the bottom to top? or plastic ring, washer, c-clip? Thanks for all the help this really isn't as complicated as it first seemed. :cheers:
Quote from: Chef GS500f 06 on June 01, 2008, 03:40:43 PM
Cool, got it. Ok ywo more questions and i think i'm good. I not sure which brass plug I need to drill to put idle screw in, what type screw do i get? Also, the washer order position- should it be washer,plastic ring,c-clip from the bottom to top? or plastic ring, washer, c-clip? Thanks for all the help this really isn't as complicated as it first seemed. :cheers:
Your mix screws are already there.They are just covered by a brass cap.There's a pic on this link that shows the location of everything. http://gstwins.com/gsboard/index.php?topic=7859.0 Just drill the cap with little to no pressure on the drill.As soon as you start to see a hole,stop,screw a machine screw into it a few turns,and pull the screw with pliers.The cap should pull out with the screw.Penatrating oil helps.I did mine plastic ring,washer,and clip.Basiclly traping the washer between the clip and plastic ring.