ninjette.org

Go Back   ninjette.org > 1986 - 2007 Ninja 250R > 1986 - 2007 Ninja 250R Tech Talk

Notices

Reply
 
Thread Tools
Old August 15th, 2022, 02:21 AM   #1
eltel
ninjette.org member
 
Name: Tev
Location: Ireland
Join Date: Aug 2022

Motorcycle(s): 2004 E250

Posts: 18
Idle not stable - carb issues?

My 2004 starts easily and runs well at speed and at normal temperature but it does have an idling problem. It starts on choke and if you leave it to warm up will eventually idle at 1200-1300 RPM which seems fine. Take the choke off too early and it dies quickly. I thought it needed a little too much choke to keep running as it was 86F outside but maybe that’s this bikes character?

The issue is you drive off down the road and at the next junction the tick over is now 4000RPM for the rest of the ride. You can bring it down with the idle adjuster but that doesn’t feel intuitive as it was idling fine at initial start-up.

Tank is clean and the fuel flow is good on this bike, you can pin the throttle and it doesn’t falter. I suspect blocked or partially blocked pilot circuit in the carbs or loose rubbers leaking air. Before I go down that route, I will check the valve clearances too.

My question is: are there any common traits or known issues with these carbs? Is there anything I should pay particular attention too? I’m happy stripping and cleaning carbs, the bank of four on my Daytona 1200 went through a period of driving me nuts until I found two blocked choke circuits that had frustrated me for months.
eltel is offline   Reply With Quote




Old August 15th, 2022, 06:08 AM   #2
jkv45
Rev Limiter
 
jkv45's Avatar
 
Name: Jay
Location: WI
Join Date: Jul 2013

Motorcycle(s): '06 SV650n, '00 Derbi GPR, '64 CA77 Dream 305, '70 CL450 Scrambler, numerous dirt bikes

Posts: A lot.
MOTM - Jun '18, Oct '16
As you stated - check for a vacuum leak.

Have you made fine adjustments to the idle mixture?

Have the carbs been synced recently?

I would do those things before pulling the carbs.
jkv45 is offline   Reply With Quote


Old August 18th, 2022, 07:49 PM   #3
Patrizio
ninjette.org member
 
Name: Peter
Location: Northeast
Join Date: Jul 2022

Motorcycle(s): Ninja 250

Posts: 10
This may not be it but my bike was doing the same
Thing.. come to find out the throttle cable was not returning back to idle. The way it was routed was putting too much bend in it so after giving the bike throttle it would sit around 3-4K. Had to re route the cable and also oiled it a bit
Patrizio is offline   Reply With Quote


2 out of 2 members found this post helpful.
Old August 19th, 2022, 04:46 AM   #4
eltel
ninjette.org member
 
Name: Tev
Location: Ireland
Join Date: Aug 2022

Motorcycle(s): 2004 E250

Posts: 18
Cable snagged

You were right Patrizio. After taking all the bodywork off to adjust the valve clearances I got a clearer view of the throttle cabling. One of the cables lock-nuts on the adjuster was loose, sometimes that nut was catching on the bracket, other times not. A reminder to check the easy stuff first.

Bike running well now. Valve clearances done, new oil & filter, new coolant, new spark plugs. I am not mad about the airbox to carb rubbers, they are probably next on my to do list but will do for now.
Attached Images
File Type: jpg Ninja Refresh.jpg (112.4 KB, 9 views)
eltel is offline   Reply With Quote


1 out of 1 members found this post helpful.
Old August 19th, 2022, 06:43 AM   #5
Patrizio
ninjette.org member
 
Name: Peter
Location: Northeast
Join Date: Jul 2022

Motorcycle(s): Ninja 250

Posts: 10
What’s wrong with the rubbers to the carb? I am asking because it seems as if mine will back off over time. Should there be a hose clamp around those?
Patrizio is offline   Reply With Quote


Old August 19th, 2022, 07:08 AM   #6
eltel
ninjette.org member
 
Name: Tev
Location: Ireland
Join Date: Aug 2022

Motorcycle(s): 2004 E250

Posts: 18
Quote:
Originally Posted by Patrizio View Post
What’s wrong with the rubbers to the carb? I am asking because it seems as if mine will back off over time. Should there be a hose clamp around those?
There is no hose clamp, just some elasticated springs on mine but they are not great. I have seen this mentioned a few times on the forum. Some have added a hose clamp by the looks of it.
eltel is offline   Reply With Quote


Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
4k Idle after carb cleaning chibit89 2008 - 2012 Ninja 250R Tech Talk 11 October 8th, 2016 08:49 AM
Idle issues - Idle is different every time I start up. 106 1986 - 2007 Ninja 250R Tech Talk 6 November 13th, 2014 04:57 PM
Idle RPM higher than stable when first started, then goes back down? farabeejunior 2008 - 2012 Ninja 250R Tech Talk 7 October 2nd, 2014 08:18 AM
idle issues jgcable 1986 - 2007 Ninja 250R Tech Talk 9 July 30th, 2014 03:13 PM
Carb idle problems n4mwd 1986 - 2007 Ninja 250R Tech Talk 13 May 4th, 2012 04:33 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Motorcycle Safety Foundation

All times are GMT -7. The time now is 06:37 AM.


Website uptime monitoring Host-tracker.com
Powered by vBulletin®
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.
Except where otherwise noted, all site contents are © Copyright 2022 ninjette.org, All rights reserved.