Welcome, Guest
Username: Password: Remember me

TOPIC:

Idle too high and rpms drop off too slow 7 years 8 months ago #13571

  • Ledkz1300
  • Ledkz1300's Avatar Topic Author
  • Offline
  • Platinum Member
  • Platinum Member
  • Posts: 717
  • Thank you received: 76

kza13 wrote: I've had lots of little problems over the years, trying to wrack my old grey cells to remember what they all were, I did have another problem with fuel starvation when the bike got hot, and in OZ it's usually hot :-), turned out to be a crappy fuel line, the heat from the motor made the pipe soft and she sort of kinked a bit internally and starved my carbs, a bit of better fuel line and a straighter connection line fixed that, although now I seem to be starving a bit when I give it a gut full and keep it there, think the replacement vacuum petcock isn't feeding enough, might have to invest in a Pingle.


Initially I had other problems, including a slightly leaking petcock so I ordered the setup from pingle although it hasn't arrived as of yet. Hopefully early this week. I've also replaced the gasline with a new one and new routing which I double checked.

Again, I am having NO troubles under throttle. She pulls like a freight train under load so if my issue was fuel starvation I'd think I would be having troubles at WOT or even 1/2 throttle. Not the case.

My trouble is the idle racing and a slow return to idle when the throttle is blipped... when hot. Eventually my idle will climb to over 2000 rpm and hangs at 4000 and below. Cold evenings and fresh starts there is not a problem. Runs great.

Please Log in or Create an account to join the conversation.

Idle too high and rpms drop off too slow 7 years 8 months ago #13575

  • kza13
  • kza13's Avatar
  • Offline
  • Platinum Member
  • Platinum Member
  • Posts: 671
  • Thank you received: 97
Ok so maybe you have the balance of the carbs set too high, which means the butterflys are open a bit too far, which might make it right on the verge of lifting the slides and giving more gas thru the mains ??, just thinking of all options. Balancing carbs is weird ... I did mine a while back and asked on here what is the correct vacuum setting, seems there isn't any, just so long as they are even, but I think it's better on the low side balance than evening them up to a high carb, ok i'm suppose to be working, better get back to it, cheers
after tuesday even the calendar goes WTF
1979 KAWASAKI Z1300 A1 WITH A DJP SIDECAR
Frame No: KZT3OA003911
Engine No: KZT3OAE004153
Location: Queensland Australia

Please Log in or Create an account to join the conversation.

Idle too high and rpms drop off too slow 7 years 8 months ago #13579

  • Ledkz1300
  • Ledkz1300's Avatar Topic Author
  • Offline
  • Platinum Member
  • Platinum Member
  • Posts: 717
  • Thank you received: 76

kza13 wrote: Ok so maybe you have the balance of the carbs set too high, which means the butterflys are open a bit too far, which might make it right on the verge of lifting the slides and giving more gas thru the mains ??, just thinking of all options. Balancing carbs is weird ... I did mine a while back and asked on here what is the correct vacuum setting, seems there isn't any, just so long as they are even, but I think it's better on the low side balance than evening them up to a high carb, ok i'm suppose to be working, better get back to it, cheers


Thanks man. That is actually next on my list to try. I can borrow a set of gauges and I'm trying to track down another set so I can do them all instead of 4 at a time. I want to try everything before I commit to drilling out the pilots as it appears I can't lay my hands on any other size jets at this point.

Please Log in or Create an account to join the conversation.

Idle too high and rpms drop off too slow 7 years 8 months ago #13581

  • hillsy
  • hillsy's Avatar
  • Offline
  • Premium Member
  • Premium Member
  • Posts: 106
  • Thank you received: 25

Ledkz1300 wrote:

kza13 wrote: Ok so maybe you have the balance of the carbs set too high, which means the butterflys are open a bit too far, which might make it right on the verge of lifting the slides and giving more gas thru the mains ??, just thinking of all options. Balancing carbs is weird ... I did mine a while back and asked on here what is the correct vacuum setting, seems there isn't any, just so long as they are even, but I think it's better on the low side balance than evening them up to a high carb, ok i'm suppose to be working, better get back to it, cheers


Thanks man. That is actually next on my list to try. I can borrow a set of gauges and I'm trying to track down another set so I can do them all instead of 4 at a time. I want to try everything before I commit to drilling out the pilots as it appears I can't lay my hands on any other size jets at this point.


You can't adjust the sync within the carbs (IE: 1 and 2), so in reality you only need 3 gauges to balance the carb set.

Please Log in or Create an account to join the conversation.

Idle too high and rpms drop off too slow 7 years 8 months ago #13582

  • Ledkz1300
  • Ledkz1300's Avatar Topic Author
  • Offline
  • Platinum Member
  • Platinum Member
  • Posts: 717
  • Thank you received: 76
I was wondering about that. So why the ports on each intake if there are only 3 adjusters? Do I ignore one port on each intake pair completely? Which one of the pair should I use?

Please Log in or Create an account to join the conversation.

Idle too high and rpms drop off too slow 7 years 8 months ago #13584

  • hillsy
  • hillsy's Avatar
  • Offline
  • Premium Member
  • Premium Member
  • Posts: 106
  • Thank you received: 25
The manual says to take readings from the two ports on each carb and get an "average" vacuum measurement to use as the balance reference.

In practice, you should measure the two ports on each carb to see if there is a big difference (this could indicate an air leak, bent butterfly valve, etc), but if they are close then you only really need to use one of the ports to balance the 3 carb "pairs".
The following user(s) said Thank You: Ledkz1300

Please Log in or Create an account to join the conversation.

Time to create page: 0.072 seconds
Powered by Kunena Forum