1993 Kat wont start/stay running.

[1quikz]

Hey KR, im new to this forum just got my very first bike. 1993 Katana 600. Im relatively diversed in mechanics, but this bike is giving me some grief. Im have some issues getting the bike started when hot, when its cold it will usually fire right up on run on the choke, but doesnt like to run anywhere under 2000 rpm, it you take the choke out, it will stall out. Once its warm, its very hard to restart. can someone point me in a direction i should be going? Thanks alot.

Z

[ICEG]

im thinking you need to check the a/f screws it sounds like it might be flooding
try riding it a little bit to get it to cool down because it needs airflow for it to cool

if you dont get it running bring her over to my house you live only 100 k away

[1quikz]

I only got the bike 4 days ago, had it up on running this morning, stretched its legs around the block 3-4 times, but on the last trip when i pulled the clutch in to down shift the bike was stalling, had a hell of a time getting it started, had to nurse it home once i did. Since then i have not been able to have it start and run without the choke on.

Just out of curiousity where do you live?

[Psycho1]

Not wanting to run below 2k rpm or so is usually a classic symptom of plugged pilot jets. If the throttle setting is set to idle, the pilot jets supply the fuel to keep it running. If those are plugged, there's no fuel until the throttle is cracked open enough to start letting fuel past the needle through the main jet. Read the "Carbs 101" thread, pull the carbs, read the "Carbs 101" thread again, clean the carbs, read the "Carbs 101" thread and reinstall the carbs. Did I mention read "Carbs 101" thread. Good luck hope this helps.

Carbs 101 thread-----> http://katriders.com/vb/showthread.php?t=63557

[smokeshow81]

classic pilot issues... I've got em too.

[1quikz]

classic pilot issues... I've got em too.

will that start a no start at all? cus that the point im at now, it wont start at all, im really regretting buying the damn thing at this point.

I pulled all the plugs to check them, re-gapped them to .24-.28 as they were out a bit, still get nothing other than sputtering.

[Kreylyn]

will that start a no start at all? cus that the point im at now, it wont start at all, im really regretting buying the damn thing at this point.

I pulled all the plugs to check them, re-gapped them to .24-.28 as they were out a bit, still get nothing other than sputtering.

Bike runs on fuel/air/spark.

Pilot jets supplies the fuel for start and idle. The vacuum setup pulls the fuel through those jets and mixes it with the air. Spark ignites it all.

If the pilot jets are clogged, then not enough fuel is going to be pulled through them with the vacuum created in the carbs by the system.... so you would be very lean when it did run, if you got it to run at all.

Lean conditions at idle causes the bike to idle at high rpms, hesitate to drop in rpms when you blip the throttle, and in general run rough.

I would suggest downloading, reading carefully, and following the directions of carbs 101 to clean them. This will 95% correct any issues you may have if you do it right.

The other 5% you won't know/we won't know about until the carbs have been fully cleaned and there is still an issue.

Please note, carbs are NEVER clean enough... and you may have to do the cleaning process a couple + times before it's right.

Krey

[1quikz]

Well i took my carbs and had them rebuilt yesterday, cost 160 bucks but figured it was worth it. Re-installed them on the bike today and still wont start. The guy said they were not overly dirty at all, just some minor grim in the bottom of the fuel bowls. As of now the bike still just cranks and cranks, doesnt fire at all. Im leaning heavly toward a spark issue at this point. Is there any way to test the coil packs? Any suggestions where i should or need to turn to next? Im stumped and extremely frusterated now. any help is appreciated

[Kreylyn]

Well i took my carbs and had them rebuilt yesterday, cost 160 bucks but figured it was worth it. Re-installed them on the bike today and still wont start. The guy said they were not overly dirty at all, just some minor grim in the bottom of the fuel bowls. As of now the bike still just cranks and cranks, doesnt fire at all. Im leaning heavly toward a spark issue at this point. Is there any way to test the coil packs? Any suggestions where i should or need to turn to next? Im stumped and extremely frusterated now. any help is appreciated

New plugs?

Krey

[1quikz]

New plugs?

Krey

I pulled two wires tonite, one from each coil #1 and #3. put a spark plug in the wires and cranked the engine over and had no spark. So at this point im thinking i now have a bad CDI box. Is there any way to test these? or basically just try a new one.

[Kreylyn]

I pulled two wires tonite, one from each coil #1 and #3. put a spark plug in the wires and cranked the engine over and had no spark. So at this point im thinking i now have a bad CDI box. Is there any way to test these? or basically just try a new one.

Are you sure you have it grounded very well. Spark is really kinda weak on kats anyways, and can be hard to see. Poor grounding makes it worse.

If you don't have new plugs, I would swap them anyways (hey, your gonna need some anyways, and they are cheap)... might fix the issue.

Krey

[1quikz]

Well i changed out the CDI, with a known working one, changed the oil, it was about a half litre overfull and had the scent of gas, and changed all 4 sparkplugs. and it FINALLY started up....thank god.

BUT....

Im still having the same issue I started with, runs great on the choke. I had it running for about 20 mins, as I back the choke off slowly till i get to about 1700 rpm and the bike dies. If i ramp up the idle screw so its idleing that fast it will run completely off the choke. but any less than that and it dies. what do you guys have your idle set to? is this the best im gonan get from this bike?

[Kreylyn]

Well i changed out the CDI, with a known working one, changed the oil, it was about a half litre overfull and had the scent of gas, and changed all 4 sparkplugs. and it FINALLY started up....thank god.

BUT....

Im still having the same issue I started with, runs great on the choke. I had it running for about 20 mins, as I back the choke off slowly till i get to about 1700 rpm and the bike dies. If i ramp up the idle screw so its idleing that fast it will run completely off the choke. but any less than that and it dies. what do you guys have your idle set to? is this the best im gonan get from this bike?

Did you clean and flush/inspect the gas tank, put in all new fresh gas before installing the carbs after their cleaning?

Krey

[f00lishroy071]

Well make sure there arent any vacuum leaks. Potential places are the vacuum caps on the carbs, the intake boot o-rings may be bad, or the carbs werent installed securely

[bill@accent]

I hope you solve your problem because my bike has the same symptoms. I'll be watching this thread closley.