Ktm 50 jetting - Page 2 - KTM Forums: KTM Motorcycle Forum
LinkBack Thread Tools Display Modes
post #11 of 15 (permalink) Old 11-05-2016, 05:41 PM
Junior Member
Join Date: Nov 2016
Posts: 2
My son's 2016 is the same way..the clutch drag is crazy and it is a pain to start, sometimes the kicker won't spring back and there very little kick available to start with...I change plugs constantly that helps some but still won't start until after I hold front brake a tip bike vertical for about 15 seconds and choke then it's one or two kicks most of time..it shouldn't be this hard..when I rebuilt top end it got better but now back to normal...I've also noticed that when ita first started and he goes to take off he will twist it and it sounds like it wants to bog down but once it's warm it runs good...his silencer has some oil but it's a two stroke ya know plus it has exceaas from a busted head base gasket...any suggestions on what causing my starting and bogging problem????
Anthony50 is offline  
Sponsored Links
post #12 of 15 (permalink) Old 11-07-2016, 12:20 AM
Full Throttle
cors187's Avatar
Join Date: May 2016
Location: Helsinki
Posts: 886
Warmer heat range spark plug, but dont move up the scale to fast from what your using now.
Dropping the needle can effect off idle response for sure. Those stock needles can look like a thumb instead of a index finger . The index finger having a more tapered look.

Hmmm finding a good jet and needle racing kit for the KTM 50 carbs

Its possible , i would call around to KTM and try talk with a guy out the back.

I had a similar issue with a 50cc scooter , carby is not sophisticated , the needle looked like a thumb. All i had to do was talk with a guy out the back and he presented a very awesome "racing needle and some jets",
15euro and problem solved.The front desk guy didnt know how to figure it out.

current -2007690SM
cors187 is online now  
post #13 of 15 (permalink) Old 11-07-2016, 01:17 PM
Site Sponsors
mill tech's Avatar
Join Date: Apr 2016
Posts: 104
Originally Posted by bajadog View Post
From motorcycle repair website.

"The idle jet system (comprised of pilot air jet, pilot fuel jet and pilot fuel screw) controls from 0% to about 25% of the throttle opening. The throttle valve controls 0% to 35% of the throttle opening. The needle jet and jet needle control from 15% to 80% of the throttle opening and the main jet controls 60% to 100%. This means that when you open the throttle about one eighth of the way open, all of the gas/air mixture going into your engine is controlled by the idle jet. As you can see, the different jets over lap the operating range of each other. That is, the jet needle starts to effect things before the effect of the idle jet ends. This is something to remember when working on carbs... everything is interconnected. Change one thing and it will effect other things."

You can lead a horse to water. . . you cant stop him from pissing in it. This is sound advice and is written by someone who clearly understands the basic operating principles and circuits involved in ANY carburator. Just to be a wise-acre: How does this relate to the Stoichmetric efficiency of this carb?

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

920.893.5595 Ext 316
mill tech is online now  
post #14 of 15 (permalink) Old 11-07-2016, 02:32 PM
Full Throttle
cors187's Avatar
Join Date: May 2016
Location: Helsinki
Posts: 886
Wiki can help fill in details on your quiz question professor rod
The stoichiometric mixture for a gasoline engine is the ideal ratio of air to fuel that burns all fuel with no excess air. For gasoline fuel, the stoichiometric air–fuel mixture is about 15:1
mill tech likes this.

current -2007690SM
cors187 is online now  
post #15 of 15 (permalink) Old 12-06-2016, 02:54 AM
Full Throttle
cors187's Avatar
Join Date: May 2016
Location: Helsinki
Posts: 886
50cc carb jetting follow up.

current -2007690SM
cors187 is online now  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the KTM Forums: KTM Motorcycle Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may 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
Trackbacks are Off
Pingbacks are Off
Refbacks are On

For the best viewing experience please update your browser to Google Chrome