Will a carb sync solve my problems?

I have a 1982 kz550 ltd with tk carbs.

Off idle response/performance is horrible. In neutral, giving a snap of the throttle from an idle of 1.2k rev'd to 2k will kill the engine. Take offs are slow and stumbly, but once it reaches above 2k rpms, it catches speed and throttle can be opened. Taking off with the choke on alleviates this problem though.

However, there isn't much speed at all. At wide open throttle, there is no response. RPM's slowly rise up to a max of about 6k then stutter back down to 5.5k. The whole rpm range is weak.

-plug 1 seems fouled, 2 and 4 are running at normal, and plug 3 is white, very lean.

-clean carburetors, jets
-good spark at plugs
-valve clearances adjusted
-no air leaks

Would a carb sync fix this problem? Thanks for helping the newbie out

Checked compression???:huh:

First, welcome to the KZR nation where you will find all things KZ. Great to have you here.

IMHO, this is the usual troubleshooting sequence:

*If engine is running step 4.10 could be done first.

-0.0 Get a Maintenance Manual ASAP.
-1.0 Compression Check... as mentioned by mzandmz above.
-2.0 Valve Adjustment check/adjust.
-3.0 Ignition Timing check/adjust (including +Bat. voltage to Coil(s))... be prepared to implement the WG Coil Repowering Mod if necessary.

Only then go on to...
-4.0 Carburetion sequence...
-4.1 Fuel Tank venting.
-4.2.1 Petcock fuel flow, clean/replace internal filters.
-4.2.2 Vacuum Operated Petcock check/replace rubber parts and hose from Carb Holder Vacuum point.
-4.2.3 Inline High Capacity Fuel Filter added... seldom an option at +30 years old.
-4.3 Vacuum Leaks, check/replace Vacuum Line(s) and Caps.
-4.4 Needle Valve(s) in Float Bowls clean/replace.
-4.5 Fuel Service Lever check/adjust ... clear tube method.
-4.6 Air/Fuel Ratio adjust as per Service Manual Spec.
-4.7 Carb Sync, check/adjust.
-4.8 Idle Speed check/adjust.
-4.9 Throttle Cable(s), check/adjust/replace.
*-4.10 Carb Holders check (for leaks use WD-40 spray method)/replace.

Note that all the spec's required for your bike are in the Maintenance Manual... they may even be available from KZR members who ride this model.

Best of success.
Bill

PS
Please add your year, model and location in your signature to get the best responses... and it's considered real friendly too.
Bill

Check your battery. If one of the 6 cells is going south, yep you can get it started but not running so well.

Here's an easy way to check:

1) make sure there is distilled water in the 6 cells at the right level

2) make sure the trickle charger you own (you *do* have one I presume...?) has been used for a few hours to bring the battery to whatever its current optimal voltage level is. Now use a voltmeter to check the voltage on the battery *before the battery is put back in the bike." If you cannot get at least 12 volts after a few hours on the trickle charger, may be "new battery time."


3) put it in the bike, start the bike, rev to btwn 2-3000rpm and read the voltage across the battery. It should be at least 14 volts, since the charging system is designed to deliver at least 14 volts *when the engine is revved up* a bit.


If step 2 fails, new battery. If step 2 is OK but step 3 is not, you have a charging system problem and you'll get good running for a little while (minutes? tens of minutes?) then the bike will start not running well as the battery loses its charge and the charging system fails to keep it charged up.

G'luck to ye.

Before you check all of that, a similar thing happened to my bike and my choke was stuck on and would not close because the linkage broke.

That is very similar to what would happen as it is getting too much gas.

This may not be the problem at all but it is a simple first check...

Also do you have any add-ons like pods or at one time did? The jets may not be right if someone drilled them out then put back the original airbox (or conversely you put on pods and do not have the right jets in).

Thanks guys for the quick responses.

Took off the carbs, and choke is working fine, evilash. No mods have been done to the bike, all stock.

Bike starts up regularly, but will check battery and put on trickle charger first thing tomrrow, newOld_kz1000.

Will also check the ingnition timing and voltage at coils and fuel tank(venting/petcock). That coil mod may do the trick, bill. Compression is normal, mz.

Also, after a ride of about 20 mins, I'll set her on the sidestand. Then come back to work on the bike, put her on the centerstand and gas leaks out from the overflow tubes :S
.

"...put her on the center stand and gas leaks out from the overflow tubes."

For sure there is too much gas in the Float Bowls and your Overflow Pipes are doing their job to prevent fuel from going straight into your cylinders, down past the pistons/rings and fowling the engine oil... bad stuff that.

Two causes and their corrective actions come to mind for this symptom:

-1) The Fuel Service Level is too high. Too much fuel in the Float Bowl. Be prepared to adjust the Float height with the plastic tube method only.

Fuel Service Level

-2) The Float Bowl Needle Valve is not shutting off the fuel flow completely... dirt or debris from the fuel tank. Be prepared to clean/replace the Needle Valve(s) and or add/replace a Good Quality Inline Fuel Filter . Also be prepared to flush out and or refinish the Fuel Tank interior surfaces.



Best of success
Bill

PS
Please add your year, model and location to your signature to get the best responses... and it's considered real friendly too.
Bill

i had similar problem on kz750 twin...after days messing with carbs i checked to see if floats were actually floating. turns out one float had leak. after re-soldering float... bike ran great