Jump to content
Sign in to follow this  

Newbie Jetting questions

Recommended Posts

Alright I will paste the standard jetting specs then kinda explain why i am confused..

Model (S, E, or K): Its an 05 yz450f I think its a khein

Main jet:stock (145?)

Pilot Jet: Was stock(45?), just put a 48 in it..

Fuel screw (turns out): zip-ty was 2? but never really changed the idle?

Needle/Clip position: stock

Airbox lid (on or off):Ummm no lid? just a seat

Pipe: bent the stock, its got a FMF powercore 4

Altitude where you ride: sea level

Temperature where you ride: Arizona! and in the hot part of AZ.

Are you happy with your current configuration: Umm, im not sure if my jetting is @!$@!%^ up or not... I know the old saying is " if its not messed up dont try to fix it" or something.. I bought the bike last year new from a dealer.. Im guessing they didnt touch the jetting.. After teaching my self how to ride (23year old, for christ sake it was about time i got a bike) I looped out the bike and bent the stock muffler to hell.. I replaced it with a FMF powercore4, noticed no difference in power? but hell i wasnt really able to ride the bike and pay attention to the motor.. cause i was trying to keep it on two wheels.. SO with this I couldnt really get a feel for a good base line.

After installing the Ziptie fuel screw I tryed playing with it to set the fuel screw, but it just never made a difference how much i turned it in or out. The bike never popped on decel or had a bog.. Also on reading the forums i read about the wonder that is called "ap squirt and Modification" I read that people were taking that cover off the carb and safety wiring the ap squirt black thing to the screw, so basicly they moved insync. I guess this would make the ap timing ZERO??? I still dont think i have a bog.. the Bike rips when i roll the throttle and doesnt really stop pulling.. the top end feels flat? but im not confident in my ability to judge if the bike is running out of power or not. I just did a summer maint on it, and replaced the plug. the tip was a nice golden brown, but past the tip and on the threads was black..

the bike has that goofy 4 speed and it seems like it runs out of gear real quick.. but i guess it does get up to speed in a hurry.. I do alot of riding on the motocross track "working on jumps" but im only 20mins from Glamis dunes.. and i see my self spending lots of my free time playing on the hills with a paddle.. So heres the deal... Ap squirt mod I installed is it bad? I uped the piolt jet to a 48 thinking I could get the fuel screw to work (only made the bike pop a little on decel). Does the Main jet or Needle need adjusting from stock postions? Jet kits like JD, are they a quick anserw to help people out with jetting issues.. Perhabs im just an idiot that needs to stop tinkering..

thanks for helping and sorry for writing a novel.. just didnt want to leave anything out.. ohh and i almost frogot ( kitchen sink ) :thumbsup:

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:

Sign in to follow this