Check for vacuum leaks.
Idle
Hey guys, I have an 08 YFZ450 and the idle seems to be wacky. It idles to high, when I try to adjust it up or down, seems to have no change on the low end. Basically when I try to slow the idle down it wont get to the point where I would like it, there is no happy medium, turn it slow it wont idle down, keep turning it stalls. I cant get it idle at a good RPM.
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QUOTE (Bowtie @ Mar 8 2009, 06:29 PM) index.php?act=findpost&pid=755438
where should I be looking ?Check for vacuum leaks.[/b]
the carb boots, with it idling, spray down the boots and carb with carb cleaner and if it alters the idle, then you have a vacuum leak, be careful around the exhaust.
QUOTE (Bowtie @ Mar 8 2009, 06:41 PM) index.php?act=findpost&pid=755464
actually I did that yesterday. No change in idle. Its almost like its an on/off switch ?
the carb boots, with it idling, spray down the boots and carb with carb cleaner and if it alters the idle, then you have a vacuum leak, be careful around the exhaust.[/b]
actually I did that yesterday. No change in idle. Its almost like its an on/off switch ?
The same thing has been happening to me, everytime I try to adjust the idle it just dies on me. Mine stalls out in first gear and neutral ALL the f'ing time and is a b!tch to start back up sometimes.
I put a bigger main jet in (170) with a 45P and somewhere around 3rd clip and still can't figure out why is runs and idles like crap most of the time. ??? I didn't find any leaks on the boot, but ws seaching here this morning and found something about bypassing a clutch wire. Can anyone tell me if this could be the solution to my problem?
I put a bigger main jet in (170) with a 45P and somewhere around 3rd clip and still can't figure out why is runs and idles like crap most of the time. ??? I didn't find any leaks on the boot, but ws seaching here this morning and found something about bypassing a clutch wire. Can anyone tell me if this could be the solution to my problem?
QUOTE (07HOOLIGAN @ Mar 9 2009, 06:19 AM) index.php?act=findpost&pid=755576
Sounds very similar to my problem. 172 main, 45p, No airbox lid, stock needle, zip tie mod. Mine will start right back up though.
Does yours idle at a normal RPM ? Or is it high ?
The same thing has been happening to me, everytime I try to adjust the idle it just dies on me. Mine stalls out in first gear and neutral ALL the f'ing time and is a b!tch to start back up sometimes.
I put a bigger main jet in (170) with a 45P and somewhere around 3rd clip and still can't figure out why is runs and idles like crap most of the time. ??? I didn't find any leaks on the boot, but ws seaching here this morning and found something about bypassing a clutch wire. Can anyone tell me if this could be the solution to my problem?[/b]
Sounds very similar to my problem. 172 main, 45p, No airbox lid, stock needle, zip tie mod. Mine will start right back up though.
Does yours idle at a normal RPM ? Or is it high ?
QUOTE (ktosca @ Mar 9 2009, 10:42 AM) index.php?act=findpost&pid=755580
Seems like it idles high, then when I adjust it the thing craps out on me. It sucks trail riding with the old farts on their 4x4s cause I spend most of my time trying to restart my quad. :strokin:Sounds very similar to my problem. 172 main, 45p, No airbox lid, stock needle, zip tie mod. Mine will start right back up though.
Does yours idle at a normal RPM ? Or is it high ?[/b]
QUOTE (07HOOLIGAN @ Mar 9 2009, 07:54 AM) index.php?act=findpost&pid=755581
Well hopefully, we will get some help from the knowledgeable people on this forum.
Seems like it idles high, then when I adjust it the thing craps out on me. It sucks trail riding with the old farts on their 4x4s cause I spend most of my time trying to restart my quad. :strokin:[/b]
Well hopefully, we will get some help from the knowledgeable people on this forum.
Do you do any work to it were you had to mess with the throttle cable. I had the same problem yesterday. I did some work on mine took the throttle off and didn't route the cable back right. it would idle high then stall so i lowered it and it wouldn't run. tried giving it gas then it would start and be high let off the gas and it would stall. took the air box off and seen the slide wasn't going down all the way. fixed the problem then rest the idle. Idles great now.
I'll have to check that. I did take it off doing something, either taking the carb out or maybe the sip tie mod a while back. Would my throttle cable need adjusted maybe?
dont adjust alot at once only adjust at most a quarter turn. adjust,let it idle for about five minutes and see what it does. if you cant adjust your idle using the black nob you have problems else where. make sure your throttle line had no binds ups. spray some WD on your thumb throttle and take the cover off where the throttle cable goes in and clean that area up. all you guys have no mentioned anything about the fuel screw, screw it all the way in and start at 1.5 turns out. make sure everything is perfect
QUOTE (Blackedyfz450 @ Mar 9 2009, 08:21 AM) index.php?act=findpost&pid=755589
I will have to check my throttle cable, my fuel screw is 2.5 out. If it is the cable though, why would the idle screw act that way ?
dont adjust alot at once only adjust at most a quarter turn. adjust,let it idle for about five minutes and see what it does. if you cant adjust your idle using the black nob you have problems else where. make sure your throttle line had no binds ups. spray some WD on your thumb throttle and take the cover off where the throttle cable goes in and clean that area up. all you guys have no mentioned anything about the fuel screw, screw it all the way in and start at 1.5 turns out. make sure everything is perfect[/b]
I will have to check my throttle cable, my fuel screw is 2.5 out. If it is the cable though, why would the idle screw act that way ?
your jetting and clip position is weird for a stock bike. i would go 45 165 and stock needle position 2.5 turns out on screw and start it back up. go from there. the "clutch wire" shouldnt be your problem. you either reffering to the system that senses when the clutch is in so you dont start it in gear, or the TORS which will either make your bike work, or not work at all, and shouldnt affect the idle at all.
QUOTE (Joester @ Mar 9 2009, 09:23 AM) index.php?act=findpost&pid=755605
I was going by what was recommended on this forum for jetting specs. I have a 45p and a 172m HMF slip on, no A/B lid. I have a 165 as-well. Should I try that ? I live in Ma. not sure of the elevation.your jetting and clip position is weird for a stock bike. i would go 45 165 and stock needle position 2.5 turns out on screw and start it back up. go from there. the "clutch wire" shouldnt be your problem. you either reffering to the system that senses when the clutch is in so you dont start it in gear, or the TORS which will either make your bike work, or not work at all, and shouldnt affect the idle at all.[/b]
because if the throttle cable is caught up somewhere its holding the slide open a little or alot and your not going to be able to get an idle because its like your giving it gas. i spent about an hour pulling my hair out trying to figure it out. why mine was doing it.
QUOTE (ktosca @ Mar 9 2009, 12:28 PM) index.php?act=findpost&pid=755609
what part of mass?I was going by what was recommended on this forum for jetting specs. I have a 45p and a 172m HMF slip on, no A/B lid. I have a 165 as-well. Should I try that ? I live in Ma. not sure of the elevation.[/b]
If the slide is open a little (like I was giving it a little throttle) it would run anyway, not stall out right? I'll try anything though. I turn the idle screw and it dies, I changed the main jetting from 165 to 170 and it still didn't make a difference, it's very AGGRAVATING! ha ha
QUOTE (Opps @ Mar 9 2009, 08:36 AM) index.php?act=findpost&pid=755616
Cape Codwhat part of mass?[/b]
QUOTE (07HOOLIGAN @ Mar 9 2009, 08:41 AM) index.php?act=findpost&pid=755619
Im going to check my t-cable and see if I screwed up some where. I hear what your saying though about giving it a little gas. When you turn your idle screw up, do your RPM's go up with it, or stay the same ?
If the slide is open a little (like I was giving it a little throttle) it would run anyway, not stall out right? I'll try anything though. I turn the idle screw and it dies, I changed the main jetting from 165 to 170 and it still didn't make a difference, it's very AGGRAVATING! ha ha[/b]
Im going to check my t-cable and see if I screwed up some where. I hear what your saying though about giving it a little gas. When you turn your idle screw up, do your RPM's go up with it, or stay the same ?
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