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Main Area => General GS500 Discussion => Topic started by: Tyrant171 on April 03, 2005, 09:29:41 PM

Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 09:29:41 PM
First of all, I'd like to say that I'm sorry for bombarding you guys with so many stupid posts lately, but I've been so lost with everything and your posts have taught me so much.

Anyway, I have this 97 GS500 that I recently bought and now I must rebuild the carbs because they were leaking into the cylinders (the bike, so far, has been nothing but a pain in the ass). Now, the guy I bought it from installed a K&N air filter......which would make the jetting different than stock, right? What I hope to do is reverse everything this guy had done to the bike (craptacular neon light mod, spray paint on 2 panels, stickers everywhere), which would include putting a stock air filter in the bike. I hope to order the stock air filter through BikeBandit and install the stock 122.5 main jets (I think the guy put 128 jets in there). Will this work? Will I be able to just take out the K&N and put a stock filter in and replace the main jets?

This may be an astronomically dumb question, but I'm really new to this.
Title: No ...
Post by: The Buddha on April 03, 2005, 09:36:21 PM
He had 128's in it ... OK you are screwed ... Open the top of carbs and pull the needles out ... if they have 5 notches on them ... OK leave it alone and pray ... you got DJ ... The correct stage 1 ket with DJ needle on clip 2 is supposedly 118 ... Buy a 117.5 mikuni and use that maybe ... If You have K&N lunch box filter and its got pipe ... you prolly need DJ134 mains or try mikuni 135's ... that's the stage 3 ... IN any case ... stock mains wont do for the stock air filter ... cos its a DJ needle ... In any case post the setup and we might have a better guess ...
Cool.
Srinath.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 09:36:47 PM
Or......if I were to keep the K&N filter in, what kind of carb set-up would I need? What size jets would I need? I don't know if the p.o. knew what he was doing when he re-jetted it (he's an idiot), so I'm thinking he maybe used the wrong size jets.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 09:38:47 PM
What if it's not a DJ needle?
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 03, 2005, 09:40:15 PM
why would you want to go back to paper?  Ok, nevermind, it's your bike.

Stock mains are 122.5, but most people go with 125 mains on a pure stock bike.

Stock primary jets are 37.5 (in case he changed those too)

check your jet needles to make sure there arent any washers under the clip, stock doesn't have any other than the fat plastic one

check your float heights and the float needle tips for damage/wear for that flooding issue

edit... left room and came back while typing this...  ok this is all for non-dynojet set-up
Title: Stock
Post by: The Buddha on April 03, 2005, 09:40:36 PM
If its stock needle ... Its got some numbers on it ... N-027 or whatever ... if so ... all our jetting tricks will work ... so we're good ...
Cool.
Srinath.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 10:20:28 PM
So.....notches on the needle would mean it's a DJ needle. No notches and numbers instead would mean stock needle?

Sorry, I need everything explained very basically. :(
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 10:23:02 PM
Um, I saw you said something about Dynojet. He DID have a Dynojet sticker on the bike, so I'm guessing he used one of those kits.
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 03, 2005, 10:23:11 PM
yeah, you got it... by notches he means small slots in the shaft of the needle that allow a circlip to be installed on them.  there should only be one on a stock needle.

I didn't notice numbers on my stock jet needles, but then again, I wasn't looking for them...
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 10:27:48 PM
Ooooooh, okay, I think I'm getting it now. Because he used the Dynojet kit, they're probably DJ needles, in which case I should get a 118 main jet? That would be cool for the K&N filter?

Sorry srinath, your post was really confusing to me at first with all the numbers and whatnot. :O
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 03, 2005, 10:36:22 PM
suzuki stock jets (mikuni) and Dynojet jets have a different numbering system.  

srinath is suggesting a 117.5 mikuni jet or a 118 Dynojet jet (if you can find a pair without buying the whole kit)

you still need to check the needles. just because all signs point to them being Dynojet ones doesn't mean the previous owner didn't just stick in the mains and skip that step...  (dumber things have happened)
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 10:39:04 PM
Alright.....I'll definitely check the needles ASAP (my carbs are currently in my friend's garage). So, what do you think this guy could've done wrong during the re-jetting if he used the Dynojet kit? Could the 128 main jets be the problem?

Also, thanks for all your help man. :)
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 03, 2005, 10:46:37 PM
well IMHO the first wrong thing he did was use a Dynojet ket...lol

not sure, I thought stage one was a 118 and stage 3 was 134... I've never seen a stage 2 I think Dynojet did away with that kit.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 03, 2005, 10:53:24 PM
So what the hell was this guy doing if he put 128 jets in using the Dynojet kit? I would imagine that the kit comes with the 118 jets. Hmmmm.......I hope I'll be able to get to the bottom of the problem with my carbs.
Title: DJ
Post by: The Buddha on April 04, 2005, 12:46:33 AM
OK DJ kit comes with 118, 122, 128 and 134 mains ... The needle is a steeper taper and more drastic in the last 1/2 inch I think ... You have K&N lunch box and pipe right ... 134 is the mains they want you to use, and needle on 3 position ...  If you are runnig stock filter in stock airbox and stock pipe I guess 118 DJ mains are the right ones. I guess you should confirm what needle you have and post back ... and also what filter and pipe ... Then we can rig some sorta combo that might work ... DJ kits have gone awry for a lot of people ... even those following exact instructions ... That slide drill and plug and in general the concept of very steep tapered needle is basically flawed ... they strated that idea by telling people ... hey you dont have to take carbs off ... just take the tops off and install these needles ... Then slowly it got so complex they just added and added crap till its now far too complicated for anyone to do it right ...
Cool.
Srinath.
Title: Question about K&N air filter and jetting
Post by: oldskool on April 04, 2005, 06:39:36 AM
this doesn't have anything to do with the DJ problem, but, do the pilot jets need to be nonbleed type?  i read in a previous post where someone specified nonbleed pilots.  if i order #40 mikuni pilots, are they already nonbleed or do i need to specify that i need nonbleed?
thanks for any advice.
Title: Buy non bleeds ...
Post by: The Buddha on April 04, 2005, 09:26:01 AM
Buy non bleeds in 40 ... and dealers screw up or cant find it ... often ... I have ended up sending it to people ...
Cool.
Srinath.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 10:31:14 AM
Okay, I looked at the carbs but couldn't find the needles. Are they under the black covers on top?
Title: Question about K&N air filter and jetting
Post by: callmelenny on April 04, 2005, 10:44:35 AM
Quote from: Tyrant171Okay, I looked at the carbs but couldn't find the needles. Are they under the black covers on top?

Open the top of the carbs and pull up (carefully) the diaphragms. That long shiny thing is the needle.

You do have a manual right? :roll:
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 01:34:22 PM
Yeah, I have a manual. Anyway, I pulled out the needles and there don't seem to be any notches. So, I dunno if the p.o. used a Dynojet kit or not. As I said, the main jets were 128.

Well, my friend's dad (who has been working on bikes his whole life) said that he wants me to get the stock main jets (122.5) and the stock needle jets and that will work fine (he's going to re-jet it for me). I told him that I read that, with a K&N air filter, you cannot use stock jetting. He said that's nonsense.....now I dunno what to believe. HELP!!!!!! :(

EDIT: Actually, there are 5 notches at the bottom of the needle, by the washer, but aren't those on every needle jet? There were no numbers on it, either.......
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 08:04:49 PM
BUMP
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 08:53:04 PM
Jeez.....if I were to buy the stock needle jets on BikeBandit, they're like $26 each. I NEED to know that my friend's dad is right in wanting me to buy those before I go ahead and do it.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 08:59:48 PM
If this helps anybody with helping out with my problem, I just checked the filter and it's a K&N SU-5589.

http://www.knfilterchargers.com/search/product.aspx?Prod=SU-5589

What is the jetting supposed to be for that?
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:04:00 PM
those notches are what we were talking about.
that's a DJ needle.  Your buddy that want's to put in all stock jets... it will work, but with a K&N you will be VERY lean.  (these bikes are lean right off the factory floor) a lot of guys will think they can adjust this with the mix screw, but that only adjusts idle mix. you crank the throttle open and it's all jets doing the mixing.

If you have a free flowing pipe or after market can, you could damage the engine running stock jetting. So if you HAVE to go all stock, go back to stock pipe and stock airbox/paper airfilter.

really need to know ... stock or aftermarket pipe???  to give you a better clue where to start.
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:06:12 PM
by the way, if he puts those stock 122.5's in you'll have to put stock needles back in too. (probably not a bad idea in any case)
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 09:09:17 PM
It's a stock pipe.
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:17:05 PM
ok.

stock pipe, K&N filter in the airbox, DJ needles, 128 mains.  just change the mains to 118 (or srinath's suggestion ;of the mikuni 117.5's)

move the clip on the needle to #2 notch (2nd highest, or 2nd furthest away from sharp pointy end of needle)

after that, CHECK THE FLOATS!!! (likely one of your problems)

then assemble the carbs(making sure you don't pinch the diaphrams or lose the tiny o-rings at the tops of the carb near the diaphram),
turn the mix screw 3 full turns out (screw in all the way then back out 3 full turns)

start bike, synch carbs as needed, and adjust mix as needed
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 09:20:39 PM
The guy who is fixing my bike kept on saying that the needles in the carbs now may or may not be the stock needles.....he says that EVERY needle jet has those notches. I tried arguing with him that they are probably DJ needles, but he wouldn't listen. So the stock needles DEFINITELY do not have those notches?

Also, really quickly just so I'm sure, in this picture, the needle jets are # 18, right?

http://houseofmotorcycles.bikebandit.com/PartsBandit/Assets/schematics/Suzuki/SU0084_013.gif
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 09:25:21 PM
Does the GS500 take 6mm main jets or 8mm?

This site has both:

http://www.rageperformance.com/carburetorparts.asp
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:28:18 PM
needle jet IS number 18.

here is a pic of a stock jet. (the two washers on the shaft arent stock,those are added in a DIY rejet, but as you can see, no notches)

(http://img.villagephotos.com/p/2004-12/911936/tn_DSCF0061.jpg)
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:33:23 PM
8mm large round
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 09:34:33 PM
Ah.......okay, I'm gonna show that picture to him. It's gonna be hard to convince him that I should just use different-sized main jets. He does have a lot of experience, and therefore thinks that he's right about everything. I'm just gonna have to tell him to use the 118 main jets I'm gonna get, or I'm not gonna let him do it.
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:38:49 PM
not knocking the guy's experience, just with these particular carbs the guys here in the board probably are more familiar with parts and set-up
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 04, 2005, 09:41:21 PM
One last thing.........

(I appreciate this SO much man, you're saving my life here!)

The guy re-jetting my carbs is gonna totally rebuild the carbs (I already bought the kit) and I'm gonna have him use the 117.5 Mikuni main jets and the settings you said, but is there anything else that I might need for the re-jetting? Do you think there are any parts or anything that might have been installed wrong/not installed at all when the p.o. used the Dynojet kit?

It just feels like using the 117.5 main jets would be too easy......
Title: Question about K&N air filter and jetting
Post by: cummuterguy on April 04, 2005, 09:49:38 PM
the mikuni 117.5's are srinaths idea... I've never tried to adapt mikuni jets to a dynojet needle. hopefully it works

you might want to check your slides to see if they have been drilled and or plugged. see THIS TOPIC (http://www.gstwins.com/forum/viewtopic.php?t=15907) for more info on that
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 05, 2005, 08:29:14 AM
Well, I'm just gonna go with the stock mains and needles. Will I need anything else to replace all of the stock stuff in the carbs such as washers or anything?
Title: 118
Post by: The Buddha on April 05, 2005, 08:54:59 AM
5 notches = DJ ... If you want to use the K&N in air box and stock pipe ... the mains probably should be 120's ... I dunno man, no one has posted back about getting a DJ kit working right ... and I did a few last year and they didn't post back either ... You just need smaller jets ... I didn't read all the posts fully ... but 120 and DJ needles might be the best starting point ... stock needles might not be needed ... and in any case stock mains are definetly not ... in reality ... K&N in air box and stock pipe you can use 125 mains with stock needle ... I'll see if I fcan find another set of stock needles ... and if I do its $10 for the set. Send me the DJ needles when done. Then we'll all know what to set your bike to ...
Cool.
Srinath.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 05, 2005, 09:13:33 AM
That would be AWESOME if you could find some stock needles for me.....then I could just buy 125 mains.

So.....don't use 122.5 mains with stock needles and K&N filter?
Title: I forgot ...
Post by: The Buddha on April 05, 2005, 09:05:08 PM
Oh man I forgot ... I'll look now ... BTW you want the whole kit and kaboodle ... 125 mains, 40 pilots, washers, bolts and needles ... that whole lot shipped for $30 ... yea pretty much $20+10 ... OK ... I better spend time and figure out the DJ crap ... send me Needle and 128 maybe ... when you done ...
Cool.
Srinath.
Title: Question about K&N air filter and jetting
Post by: dgyver on April 05, 2005, 09:34:33 PM
If you want a pair of stock needles, I will trade for the DJ needles.
Title: Question about K&N air filter and jetting
Post by: Tyrant171 on April 05, 2005, 09:45:34 PM
srinath, that would be awesome! Please respond to this so we can exchange info. :)
Title: Lemme look ...
Post by: The Buddha on April 05, 2005, 09:49:15 PM
OK lemme look ... But hey get dgyvers ... they are free for your DJ's ... I have to sell it cos I sold to like 3 people for $10 in the last month ... and wont be fair ... The rest of the jets are $20 shipped ... so I can send you that ...
Cool.
Srinath.