PITA to start!!


17 replies to this topic
  • TwIzTeD NuTz

Posted July 28, 2008 - 06:41 AM

#1

Ok guys my 03 wr450 is a major pain to start. Im curious if anyone can provide me with some answers. When i bought the bike i was told that i had to pump the carb 5-7 times then start it, this doesnt seem right to me so i have been tinkering with jetting and still cant get it to start easier. It takes about 15-20 kicks to get it to fire up. The valves were supposedly checked before i bought the bike, so im leaning towards jetting being screwed up. Im wanting to make the bike a street legal SM and i dont want it to be that hard to start. please help :ride:

  • kskyles

Posted July 28, 2008 - 08:12 AM

#2

what's your current jetting setup? post your mj, pj, leakjet, # of turns on your mixture screw, needle type, and needle position. then your temperature and elevation. i'm sure we can get that thing to kick over easier.

  • TwIzTeD NuTz

Posted July 28, 2008 - 08:18 AM

#3

ill take the carb back apart tonight, i have changed jets so many times i forgot what sizes are where now =)

  • Desracer

Posted July 28, 2008 - 03:31 PM

#4

Try a 168 main and a 48 pilot for a ball park start point. I still use the twist three times system when cold with the choke and it does make it start quicker.

  • jj546

Posted July 28, 2008 - 04:40 PM

#5

My ritual ( as was the previous owner who told me ) is to turn gas on, choke on and lean bike over 'til the peg hits the ground. I know it sounds dumb, but the little extra gas that runs in seems to do the trick-- never more than three kicks cold and almost always use the hot start when warm. You can always let off if it doesn't start, but it can get too late if you try something else first( pumping, part throttle etc..)

  • TwIzTeD NuTz

Posted July 28, 2008 - 07:24 PM

#6

Ok heres the specs of the jetting that i have set it too. Pilot 48 Main 160 leak jet 40, and there is a jet i have never messed with according to the manual its called the starter jet its a 65? Thanks for the input guys. also just one other thing the needle is a JD red on the 4th clip i know this doesnt effect starting but is this setting right for the needle?

Thanks,
John

  • TwIzTeD NuTz

Posted July 28, 2008 - 08:04 PM

#7

Ok well i have been playing with it for a bit, and im leaning towards valves now. Im checking them and going to make the proper adjustments if needed. Anyone else believe it may be the valves being too tight(intake)?

  • suzukipoo

Posted July 29, 2008 - 05:33 AM

#8

When my bike becomes hard to start i check my valves 9 out of 10 the valves are to tight causing them to stay a little open, riding the cam!! Thus hard to start!!
Hope this helps?

  • TwIzTeD NuTz

Posted July 30, 2008 - 04:36 AM

#9

So i checked the valve clearances, if your sitting on the bike, the far right and far left checked within spec. The middle one did not pass so i pulled the cam, and the buckets. The far left had a 185 shim, the far right had a 186 shim and the middle had a 165 shim. I couldnt get any of my feelers to pass i dropped down to a .02 and it still wouldnt pass. I swapped the shim for a 155 and still none of them would pass through. then down to a 145 and i could get a .07 to pass through but not the spec .10, now it has a 140 in it does this not seem a little drastic ???? or am i just being paranoid?

Also going through the carb i found a 100 in the PAJ the ACV is still fully functional i swapped the PAJ back out for a 85(stock). so now my jetting is as follows:
JD Red needle 4th clip
160 main
48 pilot
65 starter
40 leak

Thanks again for all the input guys

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  • WR_Dave

Posted July 30, 2008 - 05:32 AM

#10

Just make sure when you are checking the valves that the feeler blade isn't hanging up on something in there as that will give you a false reading. Do it as many times as you have to to make yourself feel comfortable. It seems like that is a pretty drastic change in the shims , but if that's what it takes then you have to trust your measurement. one of the valves could have sunk in more than the rest, hopefully it isn't burnt. Also when you have the carb off make sure that you inspect the o-ring on the needle valve seat. They have been known to deteriorate and leak past the needle valve seat fitting and cause the carb to flood. Your 160 main seems a bit small for your area. Will the engine still hold compression at TDC when you use the kicker? Just start at the beginning and work your way through it, I have a hard time believing a previous owners statements that aren't backed up with some documentation. Good Luck -- WR Dave

  • TwIzTeD NuTz

Posted July 30, 2008 - 05:37 AM

#11

i thought at first my blades were too wide to fit in the location where the valve was I cut my feelers in half that way i knew that they werent hanging on the sides. I was doing this at like 2am so im going to pull the cover one more time and double check it again tonight. I cant pass a .15 through it, but i can do a .12 now. I still think that its drastic and im going to double check it again tonight. There is still a ton of compression when at TDC. Where is the needle seat o ring at that your referring too? is it the one that goes on the top that holds the needle in?

  • WR_Dave

Posted July 30, 2008 - 05:51 AM

#12

If you go into the pdf manual , look at the exploded view of the carb and it is the o-ring around the top of the needle valve seat fitting for the float needle. Go to the performance index and download a free pdf manual for your bike if you don't have one. Also I don't believe you are being paranoid about the vlave moving that much, hopefully it's just a poor previous tune up. WR Dave

  • TwIzTeD NuTz

Posted July 30, 2008 - 08:50 AM

#13

If you go into the pdf manual , look at the exploded view of the carb and it is the o-ring around the top of the needle valve seat fitting for the float needle. Go to the performance index and download a free pdf manual for your bike if you don't have one. Also I don't believe you are being paranoid about the vlave moving that much, hopefully it's just a poor previous tune up. WR Dave


Im thinking about pulling the head honestly. if you look at my other thread everyone thinks the valve may be bad.:ride:

  • kskyles

Posted July 30, 2008 - 10:16 AM

#14

hey TNutz-

your main jet looks way too small, but it sounds like your valves are out of spec.

let us know what happens when you double check those valves. i hope they aren't shot. that could be expensive.

  • TwIzTeD NuTz

Posted July 30, 2008 - 10:18 AM

#15

hey TNutz-

your main jet looks way too small, but it sounds like your valves are out of spec.

let us know what happens when you double check those valves. i hope they aren't shot. that could be expensive.



its a stock pipe with the baffle removed, i think the jetting is pretty close. I ran a 168 with my full WB pipe on my YFZ pipe.

  • kskyles

Posted July 30, 2008 - 10:27 AM

#16

okay, i see....

it looks like you've got some bad valve seats. seems odd for an '05 to need a full-on valve job.

  • TwIzTeD NuTz

Posted July 30, 2008 - 10:32 AM

#17

okay, i see....

it looks like you've got some bad valve seats. seems odd for an '05 to need a full-on valve job.



Its actually an 03, i dont want to sound dumb, but this will be the first valve problem i have ran into. If the valve seats are bad does that mean it needs a new head?

  • WR_Dave

Posted July 30, 2008 - 10:42 AM

#18

Im thinking about pulling the head honestly. if you look at my other thread everyone thinks the valve may be bad.:ride:


I think that too , but didn't want to rule out a simple measuring issue first. Better to check and get the valves redone before one drops into the cylinder while it's running. WR Dave




 
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