Slight hesitation on takeoff on my 2002 katana 600

[wholehogak]

Question for everyone......Got a 2002 katana 600 with only a D and D can, no jetting (that I'm aware of), no header, no airbox mods/KN filters. When I go to take off, there is a small (but noticeable) hesitation as I turn the throttle (after having let out the clutch). It's only at the beginning of the gear, but I don't think it's every time I shift.

The bike was just gone through: new plugs, oil change, new filter and I don't doubt my mechanics ability, so I have no issues with him.

It's just a stupid little hesitation, definitely more noticeable when it's cold, but I was wondering if anyone had anything quick to check.

Thanks!

[md86]

You COULD pull the EPA caps and richen up the pilot screws a tad and see if it helps .....

[87vert]

approx what RPM does it do it at? under 3-4k?

[wholehogak]

Yeah definitely under 3-4K. I'd say from like 1500-2500. Are there any pics anywhere about richening up those pilot screws md86 mentions?

Thanks guys!

[paperairplane]

There is a lever on the left side that reduces this hesitation.... you can activate it with your left foot and usually needs to go down once or twice.

This is not a bike with massive cylinders that makes gobs of low end power - below about 6k rpms there is not much going on...

As for when it is cold, katanas are known for being cold blooded and generally tick, click and rattle like a sewing machine from hell.

[87vert]

There is a lever on the left side that reduces this hesitation.... you can activate it with your left foot and usually needs to go down once or twice.

This is not a bike with massive cylinders that makes gobs of low end power - below about 6k rpms there is not much going on...

As for when it is cold, katanas are known for being cold blooded and generally tick, click and rattle like a sewing machine from hell.

is there another gear below 1? cause thats where mine does it, trying to take off going up hill.

[wholehogak]

Which lever are you referring to on the left side? I understand the whole "katana being a cold blooded biyatch."

Thanks.

[KatanaJim]

From what I have read, there is a relationship between how fast the slides move upward, and hesitation. I raised the needles on mine and that seemed to help. The other thing I have heard (I think it was Cyber, but dont quote me), cutting the springs (at the top of the slide) is supposed to help as well.

[The CyberPoet]

If he has the stock carbs and no carb mods, he shouldn't cut the springs down. The DynoJet springs tend to produce this problem on the 98+ models because their spring is too stiff; switching back to the stock spring is the fix in that case.

At this point, I would go with MD's advice to richen up the idle settings (pilot screws), as long as:
(A) you are sure there isn't a jetkit installed (check it);
(B) you are sure the air filter is a Suzuki brand air filter and not an EMGO (which looks almost identical but doesn't restrict the flow as much, causing vacuum-building problems); AND
(C) Have already physically cleaned the surfaces of the slides with some form of cleaner (I use warm water & dish detergent normally, but carb cleaner can be used), so you're sure they aren't binding minorly and causing the problem.

Yes, the problem you describe is how fast the vacuum levels build and how fast the slide comes up in response to that. Easy way to tell if the idle fueling is set right: when you are riding at 7k RPM and release the throttle, does the exhaust burble or after-fire? If so, the pilot screws need to be opened more, or your passages for the pilot passages need to be cleaned (I'd use a fuel system cleaner through the tank, like techron).

Cheers,
=-= The CyberPoet

[md86]

Which lever are you referring to on the left side? I understand the whole "katana being a cold blooded biyatch."

Thanks.

He means the clutch , as in slip it more to keep the rpm's up , as in these bikes don't make much power down low . But , I get no hesitation on MY ratty pre750 from low rpms . I can go WOT at like 3k or less even , and though it won't throw me back in the seat , it WILL move forward without complaint .

[brooder]

Just because I feel like opening a 2 month old thread, but how hard are the air/fuel screws to get to? I'm thinking I need to try this on mine but I'm not sure I want to have to take the carbs off to check it.

[fixer]

Just because I feel like opening a 2 month old thread, but how hard are the air/fuel screws to get to? I'm thinking I need to try this on mine but I'm not sure I want to have to take the carbs off to check it.

they are on the underside of the carb. you have to pull the airbox and carbs to get to them, then carefuly drill a small hole in the plug, put a sheetmetal screw into it just a little bit and pull the plug out.

Motion Pro sells a 90° screwdriver for adjusting them while on the bike. that's part of what you need to synch the carbs, the other is a vacuum gauge.

if you're careful, you can adjust 'em off the bike.

most US bikes seem to be lean on the low end, adding a freer flowing exhaust and/or filter doesn't help that condition. hesitation coming off idle and popppping on decel are signs of this lean condition.

[brooder]

How easy is it to check to see if the caps are still on there while the carbs are still on the bike? Would a dental mirror work?

[bswasey]

That would work great to see if the plugs are out. All you need to do is check one.