Is it a jetting issue?
  • Ericeo
    Posts: 5
    Joined: Sun Mar 01, 2020 7:45 pm

    Is it a jetting issue?

    by Ericeo » Thu Mar 26, 2020 6:53 pm

    Hello all! So another 'it won't start' question, but this has a bit of a twist.

    I rebuilt the engine in my 06. (Not my first time) Wiseco 12:1, KW S.S. valves and springs. Valves are within spec. With a slight drag on the feeler gauge.. so I got tired of kicking it over and pass it on to a friend haha. He got it to start in 1-2 kicks by installing a 55 PJ ,195 MAIN and needle (NCYQ) on 4th clip. 2 1/2 turns out.. I stopped at 50PJ 168 MAIN. needle on 4th with 2 1/2 turns

    I bring the bike home and it won't start! I tried a 62PJ with no luck. I put the 55PJ back in same 2 1/2 turn and pull start, it started and ran good. Rode it through the neighborhood a bit and parked it. WON'T START.

    So my question
    1) would about 1000' in elevation effect the jetting?
    2) will to large of a pilot jet cause poor starting?
  • User avatar
    JimDirt
    Posts: 3523
    Joined: Sat Nov 25, 2006 6:31 pm

    Re: Is it a jetting issue?

    by JimDirt » Fri Mar 27, 2020 11:30 am

    Welcome to the site !! \:D/

    Question ????

    What bike is it ??? , you just said 06 , 06 what ?? , 250R or X , 450R or X , CRF150 R or F ??? , the model makes a huge difference on jetting , and yes elevation plays a large part in jetting , as does temperature ...... 8-[ :-k
    02 CRF450R
    06 CRF450X
    Image
    Weiser , Idaho
  • Aussiecrf230
    Posts: 1637
    Joined: Fri Jan 06, 2006 11:11 pm

    Re: Is it a jetting issue?

    by Aussiecrf230 » Fri Mar 27, 2020 5:25 pm

    Your starting procedure can make a big difference into ease of starting.
    Some bikes like choke so don't and others like say 3 twist of the throttle to squirt some fuel in instead of the choke.

    How do you do it?
    Ray
    Australia

    CRF230F 2004
    C30F Power Up needle
    Mains 132
    Idle 45
    2 turns out
    Baffle out, Screens In

    It starts,it runs,it gets to where all CRFs can get to without the valve or valve plate dramas
  • Ericeo
    Posts: 5
    Joined: Sun Mar 01, 2020 7:45 pm

    Re: Is it a jetting issue?

    by Ericeo » Fri Mar 27, 2020 7:03 pm

    Thank you for the welcoming. My apologies.. 2006 crf450r . I've tried choke no choke. One twist to 3 twist.
    This evening I tried a 58PJ along with different turns on the air mixture screw. ](*,)
  • User avatar
    JimDirt
    Posts: 3523
    Joined: Sat Nov 25, 2006 6:31 pm

    Re: Is it a jetting issue?

    by JimDirt » Fri Mar 27, 2020 8:11 pm

    a #58 is waaay too big

    This is where you should be with jetting (match it to your elevation)

    Jetting Guide for Main Jet:(pilot 45) CRF450R/X

    Sea level....165
    2000 ft.......162
    4000 ft.......160
    6000 ft.......158
    8000 ft.......155


    Temperature/Elevation:
    One main jet size (up/down) for every 2,000 feet or 25 degrees in temp.


    Stock jetting for the 06 450R is

    Image


    For Starting ..... Turn on the gas , and pull the choke , twist the throttle about 6 times , put your foot on the kickstarter , and slowly push it down all the way , do this several times till you feel when it is on the highest compression , then do it 1 more time , as soon as you get to the spot where the compression is highest , let off the kickstart and let it come all the way up , then give it a full HARD kick from all the way up , like you are trying to kick a Harley , it should start right up , if not do the same procedure again ..... ALL this is pointless if you do not have the jetting and carb settings to what is on the list ........ use a #45 Pilot , the most would be a #48 , but it should run with a #45 Pilot and the fuel screw set to what it is in the picture I posted , which is right out of the 06 450R Honda Owners Manual

    Also very important .... If the bike sat for several months with the same gas in it , then most likely it has gone bad ... these bikes like FRESH gas , Premium and preferably Non Ethanol , as Ethanol gums up the crab and cloggs the jets and internal passages , do not spray carb cleaner in the carb with it all together , including the Fuel Screw , it must all be removed (make sure you get the fuel screw , spring , washer , O-ring , all out before spraying any carb cleaner or it will destroy any rubber , this also includes the Floating Valve Plate Seal on the slide (you have to remove the slide to remove or replace the slide plate seal) ......

    Report back with results ...
    02 CRF450R
    06 CRF450X
    Image
    Weiser , Idaho
  • Ericeo
    Posts: 5
    Joined: Sun Mar 01, 2020 7:45 pm

    Re: Is it a jetting issue?

    by Ericeo » Sat Mar 28, 2020 4:00 pm

    a #58 is waaay too big

    This is where you should be with jetting (match it to your elevation)

    Jetting Guide for Main Jet:(pilot 45) CRF450R/X

    Sea level....165
    2000 ft.......162
    4000 ft.......160
    6000 ft.......158
    8000 ft.......155


    Temperature/Elevation:
    One main jet size (up/down) for every 2,000 feet or 25 degrees in temp.


    Stock jetting for the 06 450R is

    Image


    For Starting ..... Turn on the gas , and pull the choke , twist the throttle about 6 times , put your foot on the kickstarter , and slowly push it down all the way , do this several times till you feel when it is on the highest compression , then do it 1 more time , as soon as you get to the spot where the compression is highest , let off the kickstart and let it come all the way up , then give it a full HARD kick from all the way up , like you are trying to kick a Harley , it should start right up , if not do the same procedure again ..... ALL this is pointless if you do not have the jetting and carb settings to what is on the list ........ use a #45 Pilot , the most would be a #48 , but it should run with a #45 Pilot and the fuel screw set to what it is in the picture I posted , which is right out of the 06 450R Honda Owners Manual

    Also very important .... If the bike sat for several months with the same gas in it , then most likely it has gone bad ... these bikes like FRESH gas , Premium and preferably Non Ethanol , as Ethanol gums up the crab and cloggs the jets and internal passages , do not spray carb cleaner in the carb with it all together , including the Fuel Screw , it must all be removed (make sure you get the fuel screw , spring , washer , O-ring , all out before spraying any carb cleaner or it will destroy any rubber , this also includes the Floating Valve Plate Seal on the slide (you have to remove the slide to remove or replace the slide plate seal) ......

    Report back with results ...
    Thanks for the info! I'll give it a try
  • Leardriver
    Posts: 372
    Joined: Wed May 05, 2010 10:33 am

    Re: Is it a jetting issue?

    by Leardriver » Tue Mar 31, 2020 11:32 am

    Your large "bug sprayer" jets are covering for a dirty or clogged carb. There isn't a CRF 450 anywhere that won't run with a 45 pilot, fuel screw at 2.0 turns out, and a 162 main. We can fine tune from there, but any of them with any exhaust, any altitude, any compression ratio will start and run.

    So...There is probably some goop in the top of the pilot jet channel and fuel screw. Compressed air, a blast of carb cleaner, a metal dental pick gently wiggled up in the top of those passages, more compressed air, I suspect will start clearing things up.

    No need to remove the carb. Drain some gas out, and lay the bike down on the right side. Loosen the carb retention clamps, swivel the carb bottom up towards the left side, remove the 17 mm plug, and this can all be done in less than 10 minutes.
  • Ericeo
    Posts: 5
    Joined: Sun Mar 01, 2020 7:45 pm

    Re: Is it a jetting issue?

    by Ericeo » Tue Mar 31, 2020 3:55 pm

    Your large "bug sprayer" jets are covering for a dirty or clogged carb. There isn't a CRF 450 anywhere that won't run with a 45 pilot, fuel screw at 2.0 turns out, and a 162 main. We can fine tune from there, but any of them with any exhaust, any altitude, any compression ratio will start and run.

    So...There is probably some goop in the top of the pilot jet channel and fuel screw. Compressed air, a blast of carb cleaner, a metal dental pick gently wiggled up in the top of those passages, more compressed air, I suspect will start clearing things up.

    No need to remove the carb. Drain some gas out, and lay the bike down on the right side. Loosen the carb retention clamps, swivel the carb bottom up towards the left side, remove the 17 mm plug, and this can all be done in less than 10 minutes.
    Thank you for the advice. I did find that the accelerator pump is not pushing any fuel into the engine. I did actually use some carb clean and compressed air along with a new accelerator pump kit from Honda. While I did this I also did the zip tie mod. Now it does want to start but wont stay idling and pops out the exhaust.. I have a 45 pj 168mj and on the 4th notch of the NJ.
  • Ericeo
    Posts: 5
    Joined: Sun Mar 01, 2020 7:45 pm

    Re: Is it a jetting issue?

    by Ericeo » Tue Mar 31, 2020 10:23 pm

    I'm an idiot, I realized I put the diaphragm in wrong ](*,)
  • User avatar
    JimDirt
    Posts: 3523
    Joined: Sat Nov 25, 2006 6:31 pm

    Re: Is it a jetting issue?

    by JimDirt » Wed Apr 01, 2020 9:19 am

    So that was it ??? , you put the AP diaphragm in backwards and everything else checked out good ???

    I would still go to the suggested jets in the chart I posted , it was actually done by leardriver as he is the carb expert here .... and if he says run those jet specs , I would run them
    02 CRF450R
    06 CRF450X
    Image
    Weiser , Idaho

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