2001 katana 600 idle problem...

[KatanaDeckpi]

Hi all,

I just recently got a 2001 katana 600 with a D&D slip exhaust no jetting and have a Castrol R4 Race 5W/30 moptor oil in it and I don't know if the bike is just really really cold blooded bike or what but are the symptoms I have below normal or could it be something else.

*When I start my bike from not riding in 3 days the bike just die when it warms up(when I turn off the choke the idle just goes down and down and off), so what I do is just ride the bike (in city streets) and make sure that I hold the throttle on stop light so it won't die (the bike just wont hold the idle) during this period I noticed too that my acceleration in 1st and 2nd gear below 3000 rpm is sluggish/hesitant. But after about 25 minutes the idle speed is ok(around 1300 rpm) and won't die anymore and the sluggishness is gone, overall normal. This scenario happened twice now.

* If the bike sits overnight only I noticed that when I pulled off the choke when the engine warms up the idle settles to 1000 rpm and for the first 20 minutes or so of riding (in city streets) it will stay there in every stop light and the acceleration is sluggish/hesitant. But after 20 minutes when the engine really warms up (I guess) the idle speed is back to normal (1300rpm) and the bike rides normal.

Are those symptoms normal? The bike have a slip exhaust but not jetted, will jetting helps? or I'm better off in putting the oem stock exhaust? I ride the bike to work only tuesday to friday thats why it sits for 3 days everytime. Thanks in advance for any info and help.

By the way whenever I start it I always pull the choke all the way out and then when it warms up and the idle hit around 4000 rpm I slowly push back the choke so that it will idle around 2000 rpm (with choke) and let it sit there for about a minute or two then push the choke all the way back(off). and depending if the bike sits 3 days or overnight thats when the symptoms above happens.


Thanks,
Derick

[The CyberPoet]

You have a couple different things happening.

(A) You're fouling up your plugs. The choke should be used as little as possible (just enough to get it to 2k RPM and keep it there for 30 seconds); after that, use the throttle to keep it running if necessary. As you use the choke (which is actually an enricher circuit -- dumps more fuel), the plugs load up with more fouling. As the bike finally reaches operating temp, the plugs reach burn-off temp as well and burn off the fouling, which is part of why it wants to run right when it finishes warming up. *Seriously consider replacing your plugs* Also double-check your choke cable to see if it's sticking at all -- it shouldn't take any more force to operate than bending a paperclip.

(B) The smaller passages in the carbs are probably partially clogged by dried fuel residues. Use some techron fuel system cleaner (about 1/3rd bottle, pour in and then fill the tank to max with some high-detergent gasoline, such as Chevron's or Shell's VMax). Drive and then let sit overnight -- between the two periods, the fuel residues should be reliquified and burned off. This should help the cold-idle issue and reduce your dependency on the choke.

(C) Fuel boil-off & evaporation. When you park the bike off, between the engine being hot and the three days of sitting, some of the fuel in the carbs evaporates, primarily the aeromatic compounds (the lighter hydrocarbons in the fuel). Switching the petcock to prime for about 15 to 30 seconds, then turning back to on after the bike has been parked for three days in a row will top off the bowls again (adding fresh fuel) and should also make starting easier. You may also find that specific brands of fuel don't give you as many issues (different brands often use different mixtures and additives to acheive the same octane grades -- ones with fewer aeromatics or better stabilizers will evaporate less).

(D) Since you just got the bike, do you know if the standard maintenance (valve adjustment) has been done? If not, have it done. Valves out of spec could be adding to your difficulties, and if any are significantly out of adjustment, engine damages could occur.

(E) The Castrol R4 gives you quite a bit of extra power compared to most oils (compared to any I've tried) and is a very light-flowing oil, requiring virtually no warm-up to flow well. On the other hand, no 5-weight-basis oil is recommended for use in this engine by the manufacturer, and accelerated ring wear will probably occur whenever the oil is cool (i.e. - below about 80 degrees C / 160 degrees F) because the oil isn't as thick. This isn't a quick formula for any form of engine damages, but over 30k miles the ring wear will be accelerated compared to most other JASO-MA rated oils (at least the R4 is JASO-MA rated!). It's your call, whether you want more performance now, or longer life in the long run.

(F) Your battery may also be dying (esp if it's the original battery) -- starting the bike up may be draining it of it's reserve and subsequently much of the engine's electrical output may be going to try to recharge it. If the battery is over 3 years old, replace it for peace of mind, and seriously consider grabbing a float-maint charger (I recommend Deltran's BatteryTender WaterProof 800 as a good unit for your bike). There are easy ways to check the battery; you can find them on this page:
CyberPoet's Motorcycle Electrical Diagnostics - Battery, Charging, Maint, etc. -- at MotorcycleAnchor.com -- get your earplugs now!

(G) Finally, if the above doesn't cure it, you'll need to either disassemble/clean/reassemble your carbs (including probably replacing the O-rings), and/or go see someone with a fuel-air analyzer to determine how far off the mixtures are at idle that are causing the issues. My guess is between the carb cleaner, the new plugs and a new battery, the issues will be gone.

Cheers
=-= The CyberPoet

[KatanaDeckpi]

Thanks cyberpoet, I bought new sparkplugs from the dealer and it has this number on it "NGK CR9EK" is this correct? The R4 oil was in there when I got it and I'm planning on changing it to a regular oil or maybe a semi synthetic oil is this ok?
valve adjustment and carb sync are already on schedule to be work on. I'm thinking of putting the stock exhaust back on because I don't really want to have to deal with the carburators and the D&D is kinda Loud. Anyway I'll try your recommendations and hopefully it works. and Yeah after riding for about 20 minutes the bike just ride great no problems at all. Latez...

ps. Do I need to take the whole side fairing off to tke off the tank? also how do you take the right front turn signal light cover? do you take it off before I can take off the side fairing?

Derick

[The CyberPoet]

Thanks cyberpoet, I bought new sparkplugs from the dealer and it has this number on it "NGK CR9EK" is this correct?

Yes, this is the correct plug for your bike.

The R4 oil was in there when I got it and I'm planning on changing it to a regular oil or maybe a semi synthetic oil is this ok?

Any 10w40 API SF/SG or API SH and JASO-MA rated motor oil would be ideal. See CyberPoet's "How to understand and choose Motorcycle Motor Oils" at MotorcycleAnchor.com - get your earplugs cheaply! for more info.

valve adjustment and carb sync are already on schedule to be work on. I'm thinking of putting the stock exhaust back on because I don't really want to have to deal with the carburators and the D&D is kinda Loud. Anyway I'll try your recommendations and hopefully it works. and Yeah after riding for about 20 minutes the bike just ride great no problems at all. Latez...

If you need a stock exhaust pipe, I have one in great condition for sale -- I was going to list it up on eBay, but I'd much rather see a fellow KR member get it.

ps. Do I need to take the whole side fairing off to tke off the tank? also how do you take the right front turn signal light cover? do you take it off before I can take off the side fairing?

You are supposed to take off the lower and upper front fairings before removing the tank, but you can get away with removing the lower and disconnecting the upper at the sides to get the tank out. If you're doing valve work, take off the upper fairings, as you're likely to scratch them otherwise.

To take off the left blinker (turn signal) cover, turn the front wheel all the way to the right, reach down inside the fairing and locate the two nuts holding the front blinker assembly in place. Undo the bolts, and the lens assembly will come out (note: you have to remove the bulb retainer, which is done by rotating it and then pulling).

Cheers
=-= The CyberPoet