Can't set 1750rpms

[davepol]

Well, I wanted to do the carb sync on my kat, but I don't think it will be possible. For some reason it want stay on 1750rpms. I can set it to 2100 rpms, and although it jumps from 2000-2150 it kinda stays there. If I set it on anything lower then 2000 it stays there for couple seconds and goes back to 1100-1200.

I also noticed exhaust from first cylinder for some reason can't get the same temperature then others?

Plese help, the bike is all stock, 2006, 600. I don't know what to do? I rented carb sync tool from CP but I guess I won't need it

thanks,
davepol

[HexKrak]

Sounds like one of your main jets is clogged (in your carbs).

[davepol]

Yes, but why it won't stay on any value in the range from 1500-1900. Below it or above it no problem. Can it be that this issue happens because the carbs
are totally off?

[suzukiray]

Sounds like one of your main jets is clogged (in your carbs).

The bike isn't on the main jet at 1750-2100! Ray.

[quik89Kat]

you may have an air leak somewhere as described by a hunting idle....

is the bike fully warmed up when you attempt this? I'd ride it for 15 mins at least then try to adjust for the sync if it still does it I'd say air leak or your pilot screws are way off

[davepol]

Today I had some time to work on Kat. First cylinder is not working on idle. When I rev it for a while it gets as hot as others. I took a spark plug out and it doesn't seem to be to bad (although maybe a little bit to dark). I changed spark plugs about 8000 miles ago. Should I go ahead and just changed the spark plug, like I said in higher rpms it works. Thanks for all the advice,


thanks,
davepol

[kevin2502000]

Pilot jet plugged

[md86]

How bad does the plug look ? It COULD be loading up at idle for some reason (that'd explain why it's doing what it's doing for sure ) . What you COULD try is ..... running it up to temp , THEN putting in a good plug and synching it , so you know you got a good synch while the plug's good , then seeing what happens from there . Ate least , that's how I'D approach it . Careful though , plugs fresh from a hot engine are REALLY freakin HOT .

[davepol]

The bike is fully warmed up, when it is on choke all cylinders are working. I changed the spark plug from the second cylinder to first one, same thing, first one works on choke, works on high rmps, doesn't work on idle.

I noticed that the cable from the ignition coil to the first spark plug was really twisted, there is no cracks on the cable itself but I wonder if there is no problem inside the cable? But then if this would be the problem why would it work on high rmps and not on idle?

Thanks for all help, I really appreciate it!

davepol

[kevin2502000]

Easy way to check that is to switch the 2 cylinders around that come off the same coil. Meaning 1&4 are interchangeable and also 2&3. If you switch the wires and that cylinder still is dogging, carb is dirty.

[The CyberPoet]

As the others said, it would appear that your pilot jet for cylinder #1 is blocked/dirty/not right. It's a fairly easy fix in general, and if you turn out to need o-rings, the pilot needle, the springs, etc., I have all of them here brand new and ready to ship for the 98+ 600's.

Here's what you do:
Take off the carb cables, remove the airbox, remove the carbs. Holding the carbs over a bucket or something else to catch the fuel in them, flip them forward and let them drain. Then flip them the rest of the way over and set them on your lap. Now locate the pilot jet screw for cylinder #1


It may be covered by a brass anti-tamper cover. If so, drill a tiny hole in the cover (don't let the bit go in more than 1/8th of an inch), screw a self-tapping screw into that hole, and then using vice-grips, pry the cap out of the way.
Now stick your #1 or #2 flathead screwdriver down in the hole, locate the slot, and turn the screw counter-clockwise for 12 full rotations. Turn the carb over and catch the parts as they fall out (may need a little bang against your leg to knock 'em loose).
You should have (see reference fiche file - items 25 through 28 :
A brass needle
A spring
A metal washer
A rubber o-ring.

Inspect the o-ring. If it's cracked, lop-sided, torn or damaged in any way, PM me for another one. Check the needle as well -- if it's got significant build-up on it, try to clean it with a scotchbrite pad & carb cleaner. If that doesn't work, PM me for one of those as well.
Now spray the heck out of the hole you took those out of with spray carb cleaner (using the tube that hopefully came with the can), until you see something coming out in the actual mouth of the carb by the butterfly. In really bad cases, you may need to poke something through the hole -- if you do so, my recommendation is to use a very long nylon bristle, like from a paint brush or broom, rather than using a metal wire (which can scratch the passages).

Once you have this passage clear and have known good parts, put the parts back together in the order shown in the reference fiche above, screw them in all the way without forcing them (i.e. - two fingers on the screwdriver, no pressure). Once it seats gently at the bottom, note where the slot is, and unscrew it again 2.5 turns (thats two and a half full 360 degree rotations). Although many people toss the anti-tamper caps away, I actually tend to press them back into place with my thumb (with the hole still in them), just in case something wants to vibrate out later...

Reassemble the carbs to the bike and refill them before attempting to start.

Now try it all again.

Cheers,
=-= The CyberPoet

__________________________________________________ ________
CyberPoet's Katana Maintence and Upgrade Parts Offerings
The Best Metal Steel Aluminum Motorcycle Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.

[md86]

You're adding extra steps , CP . Cable detachment ain't necessary . Here's how I did it last time ......
Loosen plastic at top left , unbolt tank , remove tank , pull airbox-to-frame mounting bolts (on the sides of the box , 2 10mm's) , loosen 4 carb clamp screws (gotta make sure they're loose enough , as my dad found out last weekend the HARD way ) , then slip carbs/airbox out as one . Now , let carbs hang over left side , and put something under them and drain . THEN , get a towel and drape it over the bike , and flip the carbs up and onto the towel on top of the engine . You can even slip the seat back on to make a nice place to sit whilst tinkering . I find it saves more than a couple minutes this way .

[The CyberPoet]

Remember that the 98+ Carbs have dual throttle cables -- it's a far bigger PIA to try to do it without disconnecting them, especially for a neophyte who may have to drill out the EPA covers...

Cheers,
=-= The CyberPoet

__________________________________________________ ________
CyberPoet's Katana Maintence and Upgrade Parts Offerings
The Best Metal Steel Aluminum Motorcycle Tire Valves in the World, plus lots of motorcycle & Katana (GSX600F / GSX750F) specific help files.

[workinonit]

same thing happened to me except the pilot was clogged on carb #4 just clean it out and sync it up

[md86]

Remember that the 98+ Carbs have dual throttle cables -- it's a far bigger PIA to try to do it without disconnecting them, especially for a neophyte who may have to drill out the EPA covers...

Really . I did a jet kit on an'00 or something as few years ago . I don't think we removed the cables ..... Just make sure they twist the same way when you go to put them back on .