Can anyone help me? I know this is a shot in the dark in troubleshooting but I'm having problems with my 98' Gixxer 600. After not having ridden my bike for about 2 months or so (but occasionally starting it up) I took it out one day and something was terribly wrong with her.

At about 7K RPMS on every gear, the bike starts to studder as if power kind of comes down for a second and shoots back up. It's almost like a feeling where I'm on with the throttle but fuel all of a sudden doesn't get through and the power is lost.

It's at about 15,000 mi so I decided to change the plugs cuz I thought maybe that might be a problem. When I opened her up, there was a bit of oil coming out of my air box and onto the left carb. I remeber seeing a post about this long time ago but I forgot what this indicates.

Could someone please help or shoot me in the right direction. Someone I spoke to said it could be that my carbs are out of sync. Or... it could be a prob with the fuel system.

I could tell you though that it idles fine and when it operates at 6K and below, it's fine. But when I gun it to get past that, the power just studders! MAN O MAN!!! HEEEELLPPP!!!!

Some oil in the airbox is normal, as the crankcase breather vents into there.

As for your stutter, it's worth checking your fuel filter isn't clogged by crap, and spray some carb cleaner through the carbs just to make sure nothings gummed up. Balancing can only help, so it's worth doing.

[ 02-04-2002: Message edited by: NotoriousREV ]</p>

My 750 did this same thing when my timing chain jumped a tooth on the EX cam... Do you have the stock cam chain adjuster in the bike? Everyone at the shop thought it was a electrical problem, but nope... Might be something to look into..

John

Remember to clean out the "nipples" on the air box, esp the LHS one. I get oil in my air box as well and it runs into the nipples, which will need periodic cleaning. When it's full, it runs over and onto your Left Carbie.

Mine's always a bit dirty due the reason above and the throttle cables. images/icons/rolleyes.gif

REgarding the >7000rpm problem, im guessing there's some kinda blockage in the fuel system. It'll be beneficial to clean the fuel filter and carbies.

KaTz

My 98 600 did the same thing last year! I just rode her until it cleared up... About 20 min on the highway and she was fine. If it still persists after that check the diaframs on the slides... The will get dryrot and crack when not used for along time causing this same problem...

Thanks fellas. I've been riding it for the past week and it hasn't changed. I'm gonna try takin' a look at the fuel filter. Hopefully that's the problem.

Yeah I would imagine it is some old gas or your carbs/jets are gummed up. Put some new gas in there and run that tank and see how it goes.

Freak: When your cam chain jumped the cam what happend? When mine did that it split the stupid cam in half! Just wondering images/icons/smile.gif
Cam Chain Tensioner graemlins/piss.gif

jontflesh

I had the same problem on my race bike a 750, my mechanic and I rebuilt the carbs and found that this did not clear up the problem. So then we did a compression test and a leak down to see if perhaps a few of the valve made contact with the pistons, BINGO it was my valves, they did NOT make contact with the pistons but there is a layer of hardened material on the valves where it seats in the head and after time it can wear thin and cause a slight openning so you get no compression. Your probaly thinking that it would not run properly at all then , but this can effect one or more but not necessarily all the valves. I had 180lb in #1 150lbs in #2 and 0lb in #3 & 4 so at low RPMs it actually ran ok but at around 7-8 grand it cuoghed and choked so bad. A few new valves and new valve job and it was back to the races.

QUOTE]Originally posted by gixxer333:
Can anyone help me? I know this is a shot in the dark in troubleshooting but I'm having problems with my 98' Gixxer 600. After not having ridden my bike for about 2 months or so (but occasionally starting it up) I took it out one day and something was terribly wrong with her.

At about 7K RPMS on every gear, the bike starts to studder as if power kind of comes down for a second and shoots back up. It's almost like a feeling where I'm on with the throttle but fuel all of a sudden doesn't get through and the power is lost.

It's at about 15,000 mi so I decided to change the plugs cuz I thought maybe that might be a problem. When I opened her up, there was a bit of oil coming out of my air box and onto the left carb. I remeber seeing a post about this long time ago but I forgot what this indicates.

Could someone please help or shoot me in the right direction. Someone I spoke to said it could be that my carbs are out of sync. Or... it could be a prob with the fuel system.

I could tell you though that it idles fine and when it operates at 6K and below, it's fine. But when I gun it to get past that, the power just studders! MAN O MAN!!! HEEEELLPPP!!!![/QUOTE]

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Jon T. Flesh:
Yeah I would imagine it is some old gas or your carbs/jets are gummed up. Put some new gas in there and run that tank and see how it goes.

Freak: When your cam chain jumped the cam what happend? When mine did that it split the stupid cam in half! Just wondering images/icons/smile.gif
Cam Chain Tensioner graemlins/piss.gif

jontflesh<hr></blockquote>

All it did was jump... i was VERY lucky... In the long run, Suzuki replaced the cam chain, the adjuster, and all the guides.... That was at just under 15K miles... Since then I have had a manual adjuster...

John

If this is something that happend over night.. I doubt that the valve is the problem... This is very common if the cam chain jumps... And if you have a stock adjuster I bet it is a big problem...

The oil in the air box is very normal if the crank case breather is still vented into the airbox... With 15K miles on the bike, you are most likely going to have to blowby, this will cause more oil to enter the airbox...

You can check the cam timming for free, and valve job and valves is a lot of money.

John

Compression test is cheep if you do it yourself!!! It will only take you about 1hr... While you have the airbox off open the diaphram covers (take good care not to drop the little rubber O'ring) and inspect for wear and cracks/dryrot. If all seams good and your not confident in a carb rebulid yourself... Put some gumout in the tank and ride till it's ok or you get to the dealer... Also look for unwanted nests in the air box(mice) I'm not sure where you keep you bike!!!

I had this problem with my 95 RF900. The carbs needed to be stripped and rebuilt because of greeny substance clogging them (old gas, I suppose). As far as oil in air filter is concerned, it is normal with these bikes. Just drain it out perilodically by removing the nipple on the left hand rear corner of the air box.

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by raz_biker:
I had this problem with my 95 RF900. The carbs needed to be stripped and rebuilt because of greeny substance clogging them (old gas, I suppose). As far as oil in air filter is concerned, it is normal with these bikes. Just drain it out perilodically by removing the nipple on the left hand rear corner of the air box.<hr></blockquote>

Gas shouldnt go bad in 2 months.. I have had gas in my g/f's dirtbike for 6 months at a time and it starts up with no problem... You might have some dirt or something in one of the carbs...

John

Just a quick note to add - keep yer bike on a rear stand and the oil won't run to the left of the airbox all the time... Esp if you have a jet kit or worn engine. Should make the plugs last longer if they frequently fowl... images/icons/wink.gif

just a point re: outta sync carbs..my 600 would stubble at 7k, but continue till bout 9 or 10k, then run fine, but at 7k, it seemed like it was running out of gas..also..how are yur spark plugs..? also in the lower rpms, outta sync carbs, will cause the motor to run like crap..

I'm leaning towards your storage and fuel going bad and carbs gumming up. Gsxr-freak's g/f's bike is probably a two-stroker which may change things i dunno. anyhows, you can add some stabil in to you gas to clean out your carbs. Hammer-fo (...again, fo, again...) asked a good question... how ARE your plugs? plugs tell alot about how your engine is doing. compression failure and valve stuff shouldn't happen al' a da su-en ya know?

now "down wit ebonics" keg

My old plugs looked fine. No problems I saw with them. They were just worn down pretty good so I replaced them.

Mine is doing the same thing images/icons/frown.gif I just replaced the plugs and changed the oil, and cleaned the screen in the tank. No luck. Guess I'll put some b-12 in the tank and hope it just needs to be run.

Let me know if you figure this one out.

Thanks!

I have the same prob with my 98 600 and i have replaced the plugs and cleaned the carbs i think that it is the jetting and needs to be re synced and i hope that you have better luck then i do and let me know so that i can fix mine also and i hope the cam chain did not skip either that has to suck

A vaccum leak will also do this. Since you have eliminated spark as your problem, go to town with a can of wd-40 and spray around the airbox, airbox boots and intake manifolds. After that checks out, It could also be the sister problem which is an exhaust leak, but you'd likey to hear that. Also didn't you just do something to change something on the air side of the engine? Make sure your air stuff is not leaking...

Well I have another question then.

When you remove the tank, there are two rubber lines that come off the back of the tank. I guess one is a vent...What is the other one??

So neither of them need to be hooked up to anything? Just pointed down?

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by SVTCobra50:
So neither of them need to be hooked up to anything? Just pointed down?<hr></blockquote>

Nope... One is the breather and the other is for those people that dont know when to stop pumping gas... lol

John

Ha!

Thanks for the reply.

<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by SVTCobra50:
Well I have another question then.

When you remove the tank, there are two rubber lines that come off the back of the tank. I guess one is a vent...What is the other one??<hr></blockquote>

Over flow...

John

Yeah it's been a while and I know you guys asked to keep yah guys posted on what up with my bike. I have finally got around to bringing it to the shop.

The shop is near my bro's house where I keep my bike so he took it for me. They told him 2 things were found wrong.

One thing is one of the plugs were fouled. This was wierd because I had just changed the plugs too see if that would fix the problem. They couldn't find why the plug was fouled.

2nd, a couple of the jet clips were cracked... they of course had to replace these.

My baby is still kickin' it in the shop because they need to replace the choke cable on it. Unfortunately I have to keep my bike outside sometimes and I guess it just got weathered. I cover it but I guess that still doesn't help all that much. I wonder what could have caused the plug to foul 2wice? That sucks... well my bro says the shop got her back to running smoothly so that's all I really care about. While it was in there, I had a valve job done as well.

Can't wait to be riding again w/out having to worry about it acting wierd (well I hope!!!)

Thanks guys for your input!

If you can take pics and post them of the plugs, we might be able to help you find out why the are going out on you. images/icons/frown.gif

John

Damn I tossed the first set I replaced... My bro took a look at my older set and he really didn't see anything wrong on the tips... well I'll ask the shop if they still have the old plug they found fouled. I think they prob discarded them already.

Yea I bet they are gone. It could have just been a bad set... or one bad plug making the bike be a pain... Anyhow. If it does that again, take a few pics of them, but make sure you mark them with what cyl they came out of. That way if we see a problem with them, you know were to look... images/icons/grin.gif

John