Throttle Hesistation

[plucas_78]

2005 Kat, 9300 miles

Been serviced according to manual.


SO :

The last few days when I take my bike out, it seems to "bog" down
a little bit when I give it throttle, and then after a few seconds, WHAM
it takes off like a rocket. It happens in first, second, third, etc.

After 30 mins of riding it seems to go away.

note : I warm my bike up properly before each ride.

[Kreylyn]

My first guess would be a sync issue on the carbs... if no other symptoms are there.

Krey

[plucas_78]

hmmmm not sure how to interpret that.

[Sundowner]

Plucas, my 05 just started that little trick as well, it was worse when i had the slip on installed. The probelme got a little better when i went back to running Stock exhaust but is still there.

[plucas_78]

Plucas, my 05 just started that little trick as well, it was worse when i had the slip on installed. The probelme got a little better when i went back to running Stock exhaust but is still there.

Hmmmm interesting. Now... the solution? experts?

[Sundowner]

I would gander to go with Kreys advice- the carbs need to be synced.

[plucas_78]

is that expensive? why does it go away after the bike runs for a while

[Kreylyn]

is that expensive? why does it go away after the bike runs for a while

Engines respond differently based upon temperature. A hot engine is more responsive than a cold engine, or rather... a cold engine is not very responsive. It's very appearant when it's cold, but much less so when warm would be normal.

Another possible aspect is... it's a vacuum leak issue (which would/could cause sync issues) and when warm it's sealing off, or... again the engine is just more responsive to the lean condition the leak is causing.

A carb sync is simple to do for yourself, is not that expensive at all if you wanted to make a sync tool.

Do searches for "cheap to make sync tool" and carb syncs... pretty simple.

Krey

[plucas_78]

Engines respond differently based upon temperature. A hot engine is more responsive than a cold engine, or rather... a cold engine is not very responsive. It's very appearant when it's cold, but much less so when warm would be normal.

Another possible aspect is... it's a vacuum leak issue (which would/could cause sync issues) and when warm it's sealing off, or... again the engine is just more responsive to the lean condition the leak is causing.

A carb sync is simple to do for yourself, is not that expensive at all if you wanted to make a sync tool.

Do searches for "cheap to make sync tool" and carb syncs... pretty simple.

Krey

Thanks. I'm just gonna ride it out. You wanna trade bikes?

[Bart]

I've got a similar issue, just far less drastic. When I first got the bike I used the choke to start it, and had a dickens of a time getting the choke in just the right position to maintain the recommended 2000 rpms. Then I read (on KatRiders probably) that the choke is only necessary in cold weather. Given that I'm in Houston there's no such thing, so I started cranking without it - worked like a charm. Now I use just a tiny bit of throttle to maintain 2000 rpm for about 10 seconds. Then I let it idle for about 1-2 mins before riding off.

Recently I've started seeing a "glitch". If I use too much throttle at first (RIGHT after cranking) it bogs down and dies. Too little and sometimes it dies. I have to use just the right amount (very little), and rpms increase slowly even when I have the throttle in the same position. This only takes about 10 seconds or so; from there I keep it at 2k rpm for another 10-12 seconds the let it idle.

Granted it only idles at about 800 rpm for a bit (say, 15-20 seconds) then gets up to just a hair over 1000. I know (well, the owner's manual says) it should idle at 1200 which I'm just shy of. I suppose I could tinker with things like the idle speed adjust screw, the air-fuel mix or take the plunge and sync the carbs but I don't really see that I have anything to worry about right now. Once warm it idles at 1000-1100 but doesn't die.

So, sounds like a similar issue - if some expert sees something I dont let me know. Thx

[plucas_78]

I've got a similar issue, just far less drastic. When I first got the bike I used the choke to start it, and had a dickens of a time getting the choke in just the right position to maintain the recommended 2000 rpms. Then I read (on KatRiders probably) that the choke is only necessary in cold weather. Given that I'm in Houston there's no such thing, so I started cranking without it - worked like a charm. Now I use just a tiny bit of throttle to maintain 2000 rpm for about 10 seconds. Then I let it idle for about 1-2 mins before riding off.

Recently I've started seeing a "glitch". If I use too much throttle at first (RIGHT after cranking) it bogs down and dies. Too little and sometimes it dies. I have to use just the right amount (very little), and rpms increase slowly even when I have the throttle in the same position. This only takes about 10 seconds or so; from there I keep it at 2k rpm for another 10-12 seconds the let it idle.

Granted it only idles at about 800 rpm for a bit (say, 15-20 seconds) then gets up to just a hair over 1000. I know (well, the owner's manual says) it should idle at 1200 which I'm just shy of. I suppose I could tinker with things like the idle speed adjust screw, the air-fuel mix or take the plunge and sync the carbs but I don't really see that I have anything to worry about right now. Once warm it idles at 1000-1100 but doesn't die.

So, sounds like a similar issue - if some expert sees something I dont let me know. Thx

you just need to warm your bike up more.

my problem is different, bike is warmed and riding but experiencing hesitation when I gas it.

[EEEMB]

I had the same problem with my 2000 Kat 600 the other day. It started when I tried to start her without the choke on and just use some throttle instead. It started and I kept it running, but it ran like crap after that. Hesitating to accelerate through all the gears, typically around 3000-4500 rpms. Usually I leave the choke on for about 10-15 seconds, and then slowly back it off and rev the engine a few times when the choke is off and it idles after that fine. I have had the carbs cleaned, fixed, synced, all that back in march. Would it be doing this already? I've put about 2,500 miles on her since then. Maybe the petcock? the vac hose might have a leak? and is not supplying enough fuel? or too much fuel? Not sure.

[plucas_78]

Hmmm it sounds like this could be a common problem. I'm suprised it hasn't been discussed on the board before

[EEEMB]

I think I'm gonna grab some seafoam and run it through the system and see how that goes. I'll let you know.

[Mopar-Man]

It's lean.