Hello everyone from Turkey. I have a 2003 GS500.
I want to change my jets. I learnd from wiki mine jets are 17.5/60/127.5.
So i bought 20/stock/135 from ebay. I have a few question.
1-) I saw on here some people put washer/washers to needle. These washers should be #3. But i dont know what means this symbol "#". Is this size of calibre , size of wall thickness or size of hole? Also that "3" is mm or inch?
2-)How much washers should i put there??
3-)i saw expression like "2.5 turn" , "3 turn". What should i turn exactly?
4-)I am thinking about buy a k&n filter (lunch box). Is it okay with new jets if i buy? Or i should use them stock filter?
5-)whats "rejetting"? Should i rejet my carbs after change jets and k&n lunch box filter? or is this only needed when the filter is changed?
I think all the 2003's except for Canada are listed with an adjustable needle, so you don't need to worry about putting washers under the needles.
Main jets for the year (according to the manual) are 115, 127.5(Canada only) and 130.
You should be able to use the jets you bought with a stock filter and air box. The number of turns refers to the pilot screws. In some markets
the screws are concealed under brass plugs, because they don't want you to adjust them. Your pilot screws are probably adjustable. If you
don't want to mess with them, don't replace the pilot jets, just change the mains to 135. You may need to try different clip positions on the needles
after you change the mains.
Setting-up pods or a lunchbox filter can be pretty difficult to get right, these CV carbs were designed to work with an air box.
on the washers, they are rated with numbers. Number 4 washer is in a tiny box in a washer
drawer at any decent hardware store.
Thank you both. Jets will come in 25 days. I cant wait =)). How much hp i gain with air lunch? How much hp i gain only with these jets? Thanks again..
How about my rejet (5.question) =))? I still dont know what means it. Can you help me about it? Thanks 🙏
Quote from: Grimm on May 17, 2022, 12:32:21 AM
How about my rejet (5.question) =))? I still dont know what means it. Can you help me about it? Thanks 🙏
Rejet = changing your jet sizes for tuning purposes.
I understand. Thanks.
I changed my mind.I will not buy a air filter. I will use stock one with new jets.
So 20/60/135 is ok?
Should i put washer or washers on needle?
3+ or 3 turns screw?
Quote from: Grimm on May 16, 2022, 04:27:24 PM
3-)i saw expression like "2.5 turn" , "3 turn". What should i turn exactly?
To add on to chris900f's description, the number of turns of your pilot screw is from lightly seated. So you screw the pilot screw in to the carb until it lightly seats. You only seat it lightly because it is made of brass and is easily damaged. Lightly seated is your starting point. Then you count the number of 360 degree full turns from lightly seated. Whenever someone says, "2.5 turns" they mean "2.5 complete rotations of the pilot screw out from the fully seated position."
You usually start ~2.5 turns out as a starting point to get the bike running after a re-jet. Then you generally adjust the mixture screw using the "highest and best" method. That is, you turn the screw in until the bike's idle slows and note the number of turns. Then you turn the screw out until he bike's idle slows and note the number of turns. Set the idle screw between those two numbers or where you sense that the idle is "highest and best." Note the final number of turns. If it is lower than 1.5 turns you need to go down a size on the idle jet. If it is higher than 4 turns you need to go up a size on the idle jet. When you are done use the idle adjustment screw to reset the idle to 1200 rpm with the bike at operating temperature.
Quote from: Grimm on May 17, 2022, 02:12:04 AM
I understand. Thanks.
I changed my mind. I will not buy a air filter. I will use stock one with new jets.
So 20/60/135 is ok?
Should i put washer or washers on needle?
3+ or 3 turns screw?
You say you want to change your jets but you don't say why. Usually you rejet because you want to change a specific behavior of the bike. To know if those settings will be good we have to know what your goal is. It is also best to confirm the jet sizes and if you have any washers on the needle that are currently in your bike because unless you are the original owner of the bike the jetting could have already been changed. Then we can relate the behavior of your bike that you wish to change to the current jet sizes of your bike. Stock engine with Suzuki paper air filter and original exhaust doesn't really need a rejet in most countries. This is a long way of saying, if your bike runs good don't do anything.
Its been a long time since I messed with the jetting of my GS500 but if you have the stock exhaust and air filter I wouldn't do more than +1 size on the jets and 1 washer under the needle. Also, for 3 jet carbs you can just increase the mid jet size and I think it would be similar to putting a washer under the needle because the goal of both is to add fuel in the middle throttle positions. So if your jets are 17.5/60/127.5 then my total guess on jetting would be 20/62.5/130 and no washers under the needle or 20/60/130 with one washer under the needle. We have other forum members with more specific GS500 rejeting experience who might chime in with their opinions on the correct jetting.
I take my answers. Thank you so much you all. 🙏
First i will wait for come new jets (20/135) and i will try these first with a small washer. If i dont like i will make it stock again.
Quote from: Bluesmudge on May 17, 2022, 08:37:49 AM
Also, for 3 jet carbs you can just increase the mid jet size and I think it would be similar to putting a washer under the needle
I think this "mid jet" might be a myth. I think that "mid jet" is just the fast-warm-up circuit (aka "choke").
I'd need to see a flow diagram of the carb to be sure, and I am too lazy to look one up.
Quote from: Grimm on May 17, 2022, 09:57:55 AM
I take my answers. Thank you so much you all. 🙏
First i will wait for come new jets (20/135) and i will try these first with a small washer. If i dont like i will make it stock again.
Look at the underside of the carb outputs (engine side) you should see a cylindrical projection in the casting for each carb. These
house the pilot screws. You will either be able to see the screw heads(adjustable), or you will see a blank brass plug (non-adjustable).
Let us know which you have. I'm looking at a service manual, and all 2003's except Canada are adjustable :thumb:
Also, I'm curious as to what large main jet you have installed now. The service manual from 2003 shows most euro bikes got a 115 main
the UK got a 130 and Canada got a 127.5 and all the bikes had adjustable needles with clips, except for Canada.
Power? If you go from a 115 to a 135, you should notice a major difference; if you go from a 130 to 135, just a small bump.
(https://i.imgur.com/dJLPCkz.png)
+1 for Josh, there is no "mid jet".
Make sure you have no intake leaks before messing with any jetting or you are in for a world of frustrations. Ask me how I know.........
Quote from: chris900f on May 17, 2022, 08:57:45 PM
Quote from: Grimm on May 17, 2022, 09:57:55 AM
I take my answers. Thank you so much you all. 🙏
First i will wait for come new jets (20/135) and i will try these first with a small washer. If i dont like i will make it stock again.
Look at the underside of the carb outputs (engine side) you should see a cylindrical projection in the casting for each carb. These
house the pilot screws. You will either be able to see the screw heads(adjustable), or you will see a blank brass plug (non-adjustable).
Let us know which you have. I'm looking at a service manual, and all 2003's except Canada are adjustable :thumb:
Also, I'm curious as to what large main jet you have installed now. The service manual from 2003 shows most euro bikes got a 115 main
the UK got a 130 and Canada got a 127.5 and all the bikes had adjustable needles with clips, except for Canada.
Power? If you go from a 115 to a 135, you should notice a major difference; if you go from a 130 to 135, just a small bump.
Jets will come from USA in 15 Jun. I still do not know what sizes of my stock ones. I bought a K&N drop in filter last night. I will try it first with restrictive and then without restrictive.
But i think my stock main jet is not 115. Because my bike runs well. I can reach 190/195 km/h easily.
TL;DR - Might read later on when I'm bored.
190/195 km/h is like 130 mph - No GS500 gonna be able to do that.
But K&N drop in, slip-on in a post 01 bike will run spot on awesome with 20/135/1 washer under the clip and 3 turns on mix screws.
Cool.
Buddha.
Quote from: The Buddha on May 18, 2022, 04:17:19 AM
TL;DR - Might read later on when I'm bored.
190/195 km/h is like 130 mph - No GS500 gonna be able to do that.
But K&N drop in, slip-on in a post 01 bike will run spot on awesome with 20/135/1 washer under the clip and 3 turns on mix screws.
Cool.
Buddha.
Send me your number on pm i will send you video from wp. =))
All stock. 43.000km
Quote from: Grimm on May 18, 2022, 04:46:53 AM
Quote from: The Buddha on May 18, 2022, 04:17:19 AM
TL;DR - Might read later on when I'm bored.
190/195 km/h is like 130 mph - No GS500 gonna be able to do that.
But K&N drop in, slip-on in a post 01 bike will run spot on awesome with 20/135/1 washer under the clip and 3 turns on mix screws.
Cool.
Buddha.
Send me your number on pm i will send you video from wp. =))
All stock. 43.000km
Full model:
GS500K3 (P19)
Speccode:19
Ha. My Bonneville with nearly 2x the hp won't go 130mph.
It takes about 49 hp for a typical motorcycle to reach about 93mph. The hp required increases with the square of the speed difference. So to go 130mph takes about 96 hp.
Your GS500 does not make 96hp. It makes max of less than half that. So you need to reduce wind resistance to less than 0.707% what it ordinarily is to go 130mph on <49 hp, or double the power.
Quote from: Grimm on May 18, 2022, 04:46:53 AM
Quote from: The Buddha on May 18, 2022, 04:17:19 AM
TL;DR - Might read later on when I'm bored.
190/195 km/h is like 130 mph - No GS500 gonna be able to do that.
But K&N drop in, slip-on in a post 01 bike will run spot on awesome with 20/135/1 washer under the clip and 3 turns on mix screws.
Cool.
Buddha.
Send me your number on pm i will send you video from wp. =))
All stock. 43.000km
Just post it here. Anyway your jetting 20/135/1 washer/3turns will work regardless of if it made 130 mph or not.
Cool.
Buddha.
just correcting, 190kmh is 118mph. but i still doubt it, my gs might do 115mph in perfect conditions, and that'd be with the 10% speedometer error that these bikes got from factory [emoji3]
Yeah, I've seen 110 indicated on a slight downhill which really only 100 mph. Nobody is doing a true 118 on the GS500. That's SV650 territory.
We never use mph here. All bikes, cars has km/h indicators. Thats why i dont know about mph. I told you all what i see on my bikes indicator. I think nobody tampering with the indicator. Because i know history of bike. (Owner before me).
I will make a video soon ,upload youtube and share here the link.
Thanks you all again.
Ride safe. 🙏
We never use mph here. All bikes, cars has km/h indicators. Thats why i dont know about mph. I told you all what i see on my bikes indicator. I think nobody tampering with the indicator. Because i know history of bike. (Owner before me).
I will make a video soon ,upload youtube and share here the link.
Thanks you all again.
Ride safe. 🙏
I rejet my carbs. I realized the stock ones 17.5/60/115. I changed them 20/stock/135 - 3 turns - 1 washer to needle and K&N drop in air filter without restrictor (SU-5589)
So it took 3/4 hours but worth it. Its better now. I did not try top speed test yet but i am sure ill see more than 200km/h =)
Only 1 thing is negative after those; bike is warming up fast and getting hotter than before jetting.
Well anyway, thank you so much you all. I am very pleased of i have this website ♥️
Edit: it is much much better at 3.5 turns out. None anymore negaive issues..