Go Back   ChinaRiders Forums > Technical/Performance > Adventure Bikes > Zongshen RX3
Register FAQ Community Calendar Today's Posts Search
Reply
 
Thread Tools Search this Thread Display Modes
Old 07-16-2019, 02:59 PM   #1
rjmorel   rjmorel is offline
 
rjmorel's Avatar
 
Join Date: May 2007
Location: Warshington
Posts: 928
low RPM stumble

My 2015 RX3 17300 miles w/300cc kit seems to have developed a low RPM stumble when first warming up. After I get going and out on the road runs great. It's not real noticeable but when I'm just tooling around the parking lot in 1st gear like I'm trying to do low speed maneuvers it bucks a little. Get the RPMs up and runs good. Any ideas? I'm wondering if something electronic is carboned up or dirty sending bad voltage to the great whoever that makes all things go goodly?
How do you check for codes? turn key on /off 5x? Do you let the fuel pump complete its priming ? thanks rj
__________________
Live Zong, and Prosper


 
Reply With Quote
Old 07-16-2019, 03:07 PM   #2
calvarez   calvarez is offline
 
Join Date: Sep 2018
Location: Peoria, AZ
Posts: 334
Have you done the obvious such as cleaning the air filter and changing the spark plug?
__________________
2016 RX3
2002 Honda CBR1100XX


 
Reply With Quote
Old 07-16-2019, 10:56 PM   #3
NzBrakelathes   NzBrakelathes is offline
 
NzBrakelathes's Avatar
 
Join Date: Jun 2016
Location: Hell
Posts: 2,408
Stepper motor passage not clean super clean
Gently wire brush the nose of stepper
It’s not holding idle to throttle correctly so the transition from stepper to throttle isn’t right


 
Reply With Quote
Old 07-17-2019, 01:10 PM   #4
rjmorel   rjmorel is offline
 
rjmorel's Avatar
 
Join Date: May 2007
Location: Warshington
Posts: 928
Calvarez, not yet but I will, been busy and havnt checked it much since the Moab ride.
NBL, thanks I'll clean that also since I don't think it's ever been done.
rj
__________________
Live Zong, and Prosper


 
Reply With Quote
Old 07-17-2019, 01:34 PM   #5
calvarez   calvarez is offline
 
Join Date: Sep 2018
Location: Peoria, AZ
Posts: 334
How many miles are on the plug? On another forum, we're having a discussion about what a huge difference it makes to put in a new one on most bikes, and how the specified interval is often too long. And if you ride in dirt, that filter will clog up fast.
__________________
2016 RX3
2002 Honda CBR1100XX


 
Reply With Quote
Old 07-27-2019, 08:29 PM   #6
mckayprod   mckayprod is offline
 
Join Date: Oct 2015
Location: Dixon, CA
Posts: 75
I'm watching this...mine won't hold idle speed until warmed up. Just started, too, right after an oil change. I thought that might be related, but I'm leaning toward just a coincidence right now.


 
Reply With Quote
Old 07-28-2019, 02:40 AM   #7
calvarez   calvarez is offline
 
Join Date: Sep 2018
Location: Peoria, AZ
Posts: 334
Same question... Have you done the obvious such as cleaning the air filter and changing the spark plug?
__________________
2016 RX3
2002 Honda CBR1100XX


 
Reply With Quote
Old 07-28-2019, 07:41 PM   #8
mckayprod   mckayprod is offline
 
Join Date: Oct 2015
Location: Dixon, CA
Posts: 75
Good point; work in progress.


 
Reply With Quote
Old 07-28-2019, 10:58 PM   #9
mckayprod   mckayprod is offline
 
Join Date: Oct 2015
Location: Dixon, CA
Posts: 75
So, in the process of cleaning the air filter and checking the plug, I found the plug wire just hanging loose, disconnected. How I got home yesterday I'll never know, but somehow the rubber plug boot was too deep and springy and wouldn't allow the plug tip to stay connected to the wire. I know that rubber can swell when exposed to oil, and I've had a little oil seepage from the valve covers since my last valve adjustment. I cut off about 3/4 inch off the boot, seated the wire, cleaned & gapped the plug and cleaned and oiled the air filter. The bike now starts and idles without issue. New plug and wire are on order. I didn't mean to hijack your thread, RJ, but maybe this will help someone else.


 
Reply With Quote
Old 07-31-2019, 02:35 PM   #10
rjmorel   rjmorel is offline
 
rjmorel's Avatar
 
Join Date: May 2007
Location: Warshington
Posts: 928
mckayprod , Good on you. I'm going to go check my plug wire now. Mine just has a little stumble in 3rd going through town. I cleaned air cleaner, not very dirty and plug was replaced 3200 miles ago.
__________________
Live Zong, and Prosper


 
Reply With Quote
Old 08-02-2019, 01:42 PM   #11
rjmorel   rjmorel is offline
 
rjmorel's Avatar
 
Join Date: May 2007
Location: Warshington
Posts: 928
Quote:
Originally Posted by NzBrakelathes View Post
Stepper motor passage not clean super clean
Gently wire brush the nose of stepper
It’s not holding idle to throttle correctly so the transition from stepper to throttle isn’t right
So NZ, can you give me a quick instruction on where the stepper motor is and how to clean it good? I assume its on the throttle body but not sure where or how to get it out. Does gas tank need to come off? I have looked around and tried to find the info but keep running into dead ends. And well...………………………………….I'm lazy. thanks, rj
__________________
Live Zong, and Prosper


 
Reply With Quote
Old 08-03-2019, 12:29 AM   #12
NzBrakelathes   NzBrakelathes is offline
 
NzBrakelathes's Avatar
 
Join Date: Jun 2016
Location: Hell
Posts: 2,408
Quote:
Originally Posted by rjmorel View Post
So NZ, can you give me a quick instruction on where the stepper motor is and how to clean it good? I assume its on the throttle body but not sure where or how to get it out. Does gas tank need to come off? I have looked around and tried to find the info but keep running into dead ends. And well...………………………………….I'm lazy. thanks, rj
take seats off, remove the 4 stainless screws holding plastics on and the 1 tank bolt remove tank n wire hoses (5 min job)
Directly below you will see the throttle body take it out remove black stepper motor clean clean clean the passage with Q tip brake clean etc and gently scrub the styepper nose. check throttle plate closes off correctly reassemble and reset ECU.


 
Reply With Quote
Old 08-03-2019, 01:03 PM   #13
rjmorel   rjmorel is offline
 
rjmorel's Avatar
 
Join Date: May 2007
Location: Warshington
Posts: 928
Thanks NZ, you the man, really enjoying the 300 kit I got from you. It's added that little oomph where it was needed power wise, rj
__________________
Live Zong, and Prosper


 
Reply With Quote
Old 08-03-2019, 06:46 PM   #14
calvarez   calvarez is offline
 
Join Date: Sep 2018
Location: Peoria, AZ
Posts: 334
Wait, 300cc kit and low RPM stumble...weren't there other posts about those being related? I'm not sure, just something in the back of my mind.
__________________
2016 RX3
2002 Honda CBR1100XX


 
Reply With Quote
Old 08-03-2019, 08:44 PM   #15
NzBrakelathes   NzBrakelathes is offline
 
NzBrakelathes's Avatar
 
Join Date: Jun 2016
Location: Hell
Posts: 2,408
Quote:
Originally Posted by calvarez View Post
Wait, 300cc kit and low RPM stumble...weren't there other posts about those being related? I'm not sure, just something in the back of my mind.
No not related - its common on any cc size.
The odd POP from exhaust maybe a little more common


 
Reply With Quote
Reply



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


All times are GMT -4. The time now is 07:42 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.