YFZ Central banner
Cancel

Help Me Please

658 Views 11 Replies 3 Participants Last post by  1Bad06YFZ450, 
1
When my motor is warmed up it is hard to start up when I try to start it. But when It starts it runs good. I just rejetted it for the new Pro Design pro flow K&N air filter system. I didnt notice this when it was colder out side. I noticed the other day that when I would stand behind my quad the exhaust air would burn and make my eyes water.

My mods are DR-D Slip On,Cam Mod,Lid Off,Pro Design Pro Flow K&N Air Fliter Kit. Boyesen acc pump cover,power now's,air fuel screw, adjustable nettel. 170Main 48 Pilot Zip Tie Mod. I went from a 168 Main 42 Pilot and I moved my clip 2 clips to the rich side. Thanks Jimmy.
Reply
Save
Like
1 - 12 of 12 Posts
J
seems like it might be too rich. i would try a 45 pilot and move your needle to the middle clip. take it for a quick run, then check your plug. it should be light or dark brown. if its white its too lean and if its dark black or a wet black its too rich
Reply
Save
Like
1
Thanks for the reply. Do you think just moving the clip to the lean side will help. Before I noticed this with the lid on I had a stumble at WOT then I took my lid off it cured it. Now since its getting warmer out Its hard to start with the motor warm. Should I check my plug before I do any jetting. I now it runs great while its running just hard to start when warmed up.No Bog,poping,backfiring at any throttle posititon.
Reply
Save
Like
S
adjust your af screw
Reply
Save
Like
J
ya i would check it before, to see where ur at. your needle might be too rich so changing the clip would help if it was. whats ur elevation? and what clip position from the top is ur clip at?
Reply
Save
Like
J
QUOTE (Stix1107 @ Mar 11 2009, 08:54 PM) index.php?act=findpost&pid=756745
adjust your af screw[/b]
Click to expand...
ya that could be a factor too. try 2 1/2 turns out for a starting point
Reply
Save
Like
S
thats the problem gauranteed, if you are not noticing any problems while riding
Reply
Save
Like
1
QUOTE (ballsdeep450 @ Mar 11 2009, 07:56 PM) index.php?act=findpost&pid=756746
ya i would check it before, to see where ur at. your needle might be too rich so changing the clip would help if it was. whats ur elevation? and what clip position from the top is ur clip at?[/b]
Click to expand...

thanks for all the help guys..Iam not sure of my elevation. I live in Fredericksburg,Va It was 78-83 that day. My buddy did the clip and he moved it 2 clip to the rich side. My jetting at the time he moved the clip was 170Main 42Pilot and it still had poping,backfiring, then I put a 48Pilot in the carb with the lid on it cured the poping,backfiring then it would have a stumble at WOT then I took the lid off it cured the stumble. Now it was warmer that day it was hard to start.
Reply
Save
Like
1
QUOTE (Stix1107 @ Mar 11 2009, 08:00 PM) index.php?act=findpost&pid=756749
thats the problem gauranteed, if you are not noticing any problems while riding[/b]
Click to expand...
I'am to rich will that hurt anything Ya I dont noticed any problems while riding.It rips I wish I had more YFZ450 owners that lived near me.
Reply
Save
Like
S
better to be rich than lean. safer atleast
Reply
Save
Like
1
Thanks alot for all ya help. If it was my values would it be hard to start with the motor cold ad hot. I think it starts to good when the motor is cold and colder out side.
Reply
Save
Like
1
I search and all I found was that Fredericksburg,va is 147 feet above sea level.
Reply
Save
Like
1 - 12 of 12 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
YFZ Central
A forum community dedicated to Yamaha YFZ owners and enthusiasts. Come join the discussion about performance, modifications, troubleshooting, maintenance, classifieds, and more!
Full Forum Listing
Explore Our Forums
YFZ Powertrain YFZ450 & YFZ450R General Talk Suspension and Steering Maintenance YFZR-X Powertrain
Top