Is idle normally that high or are there problems.

[Anonymous]

First of all .. nice site.
My name is Luke.

I just recently acquired '83 suzuki gs550L. original 14,000 miles on it. It is in nice shape. runs great otherwise.... well this is what actually bothers me.

Fist some off topic question:
The pet cock vavle has three settings. Fuel on, PRI, RES. I am used to my two older bikes ('78 honda CB400T, '78 Yamaha Enduro 175) where there is OFF, ON, RES.)

Which one does what on this motorcyckle? (well RES is self explanatory)?

But to my actual question.
Motorcucle starts on about chalf choke. When it is worming up, the choke is very "touchy". One 1/4 of an inch makes it rev to 5000 rpm... if I back off then the engine progressively loses RPM untill it stalls. or wonders 3K-4K RPM. It stedies when it worms up.

Then it stays around 2.5K-3K. Now, I am used to my other bikes where my idle stays closer to 1K. Is this normal for the "new" motorcycles? Is the RPM actually ok for this suzuki?

Oh, yeah, and by the way, once in a while it will go down to 1K-1.5K (once it worms up)... but that's only untill I rev engine up... than back to ~3K. I did add some carb/injector (STP) cleaner to fuel and let it run. I did noticle smoother overall peration when I ride it on highwayafter about 1/4 tank. How big is the tank anyway?

I know this bike has been sitting under wrap a long time and I am fearing the dreaded idea of taking carbs apart. (I am not particularly happy about process. It's not that I can't put it back together, but it is long process and quite frankly .. pain in the a**).

But then again, I am quite aware of the possibility and it will come as no suprise should I have to do it.

Overall I really like the bike. I am still getting used to idea of high RPM riding. I mean this sucker has 12K total. Riding 55 at ~5K + is still something that I am getting used to. Nothing wrong but just getting used to it. it just feels like motor is gonna jump out of the frame.... well.. just in my head... the engine keeps humming and carries me away....

Guys... any idea on whether my bike is acting normal and what my RPM should be?

Oh yeah and by the way... that 10W-40 it says on dip stick.. how often should I replace it.?(miles)

Will appreciate ANY input on this one... thanx in advance...
I hope everyone had happy easter

[Anonymous]

You leave the petcock on the normal position. If it is hard to start put it on the PRIme position as it allows the fuel to flow without engine vacuum.

The idle can be controlled by a knob under the carberetors (not the cam chain tensioner, leave that alone) After some discussion here some people believe the high idle that occasionally drops indicates that the carbs need to be synchronized. 1-1.5k RPM is normal but when it warms up with the choke on it will go to 5k on its own.

Steve

[redliner1973]

More than likely your idle curcuit is clogged. hate to say it, but you sound like you need to pull off the carbs and remove the bowls, clean all the crap out and try again. It is really not that difficult. As for the oil, I change mine every 2000 miles, use Castrol 20w-50(it gets real warm here in AR.) and change filter every oil change. My Honda 450 ran at that 5000 RPM at hi-way speeds, and took awile also to get used to. Worry not, it is designed that way to run. it won't grenade on you unless it was it's time to anyhow. The petcock should be left in the 'on' position, as it is vacuum operated, and prime is used only when you need fuel to fill the carbs without the engine running. Don't leave it on prime, as the float valves may not seal good enough doing this and overfill into your oil. other than that, do a good tune up and enjoy it! :twisted:

[Anonymous]

Had a '79 550L that wouldn't idle below about 2K. Cleaned the carbs, adjusted point gap & timing, adjusted and synchronized the carbs, and now it idles like a dream. The bike should be idling around 1K. After cleaning & adjusting, mine would idle pretty smoothly as low as 500 RPM.

Best place to start on your bike is probably cleaning the carbs. With a good manual, you should be able to do the job in a couple of evenings.

Good luck!

Michael

[nabrams]

During warm-up, with the choke on, the bike will idle at 4K-5K RPM - This is normal. Once warmed up, the bike should idle (with zero choke) at around 1100 RPM.
The "bike-has-been-sitting, now-it-won't-run-quite-right" problem is probably one of the most common topics on this site. In the vast majority of cases (including mine), it's gummed-up carbs and/or improper air flow (or air leaks). My bike would not run right till I did ALL of the following:

1. Adjust the mixture screw for max RPM at idle (I had to remove the tamper-proof caps). They should be between 2 and 6 turns out from bottom.
2. After cleaning carbs, clean idle and main jets with a copper wire (spraying tons of carb cleaner through them didn't quite get all the gunk out).
3. Install a proper foam air filter element (mine had disintegrated).
4. Seal ALL air leaks (no matter how tiny) at all boots and at air box lid.

Good luck, and don't get discouraged. It took me a while to get my GS450 tuned right, but I learned a lot and saved a ton of money. Get a good manual (like Clymer) - that will make a huge difference.

[Hotblack]

My choke behaves the same way, and everything's fine in the carbs, and it idles fine when warmed up. It just takes a few seconds on a decent day for it to be able to idle normally, my strategy seems to be to tickle the choke once or twice, by then it will idle normally. Is that the best thing to do? Is it really ok to let that rascal idle at 5k, say on a cold day when it won't warm up so easily? I'm still getting used to the high rpm range of this beast too. I'm used to a big block Buick that would melt down at the range these engines start to wake up at 8O so the busy sound of the engine still tends to put me on edge, expecially when I first get on.

[Anonymous]

glad to hear from you guys

gland to hear from you guys. the replies were sort of mixed blessing. on one hand i found out that it is nothing major that will need repair but on the other hand ... those damn carbs.... oh well... i knew this would be possibility....

either way.... this is the course of action on which I have decided:
let motor run trhough 2-3 tankfulls with that fuel cleaner additive. (I don't want to fiddle with settings if its only minor gunk which will desolve)...

if this doesnt help... I start messing with idle adjustment. if that doesn't help... well...
WATCH OUT CARBS HERE i COME.... as I walk towards the machine with sinister grin on my face and 20 lbs hammer!!!! Muahahahaahah

thanx guys... let me know if my procedure is flawed....

thanx again

[frosty5011]

you wrote:

thanx guys... let me know if my procedure is flawed....

Well, if it's the carbs you're going to work on, then yes..........your procedure is flawed. 40-lb sledgehammer is probably the more appropriate tool to use....