YZ250 - hard starter

kkmp · 02-19-2008, 10:41 PM

I have an early 90s YZ250 2 stroke that I bought last winter. Was always a bit tough to start but got increasingly worse after a few weekend rides. I did a top end re-build and starting was relativfely easy for the first few outings then back to the tough start / no start problem. Once its warmed up it will start in one or two kicks but when cold, its a crapshoot whether it will start at all.

Any ideas to get me rolling in just a few kicks?

Thanks,

tjscott2012 · 02-20-2008, 04:10 PM

welcome to the boards, and, do you have a hotstart lever? idk whats wrong here. doesnt sound like a carb problem, but id go ahead and clean it anyways. that may help a little. are you using choke? how much?

turtlemann14 · 02-20-2008, 04:32 PM

i would check the plug if you have not yet. sounds like it is fouling out

wr250f95 · 02-20-2008, 06:43 PM

what have you been mixing your gas at?

tigmaster · 02-20-2008, 08:45 PM

2 strokes don't have hot start levers TJ. How did the old piston look? Any weird spots to it? Did you hone when you put the new piston in? How was the bore? Is your coolant system topped off? Like WR said, what is your gas mixture at right now? Have you changed the mixture? How did you break in the bike? Sorry for all the question but I am just getting the groundwork laid.

tjscott2012 · 02-20-2008, 08:55 PM

its a 2t tig

gscx · 02-20-2008, 09:28 PM

check the carburator, the pilot jet might be clogged up, and if it is nikasil plated you shouldnt hone it, but since it is older it is probly sleeved, and they do need to he honed befor you put a new piston in

tigmaster · 02-21-2008, 10:29 AM

I meant to say 2 stroke TJ. 2 strokes do not have a hot start lever. If the bike just happened to be Nikasil plated, scrub the bore out with a 3M pad ad soap and water. Its not that they shouldn't be honed, its simply that anything less than a diamond tipped hone is not going to even touch it. However, never use a ball hone on a 2 stroke, always use the 3 stone hone. Did the bike ever bog when you revved it from an idle? We you ever rolling, idling along and gave it gas to have it bog? Did it ever bog at low engine RPM's? If you answered no to all of these then the pilot jet is fine but cleaning you carburetor is something you may want to do anyways.

gscx · 02-21-2008, 02:04 PM

it might be plated, but im not sure, i do know that a 96 rm250 that i have is plated but anything older might not be

tjscott2012 · 02-21-2008, 02:37 PM

im confused, whats a hot start do again?

02-19-2008, 10:41 PM	#1 (permalink)
kkmp C Rider Join Date: Feb 2008 Posts: 2	YZ250 - hard starter I have an early 90s YZ250 2 stroke that I bought last winter. Was always a bit tough to start but got increasingly worse after a few weekend rides. I did a top end re-build and starting was relativfely easy for the first few outings then back to the tough start / no start problem. Once its warmed up it will start in one or two kicks but when cold, its a crapshoot whether it will start at all. Any ideas to get me rolling in just a few kicks? Thanks,

02-20-2008, 04:10 PM	#2 (permalink)
tjscott2012 The Spam man Join Date: Nov 2007 Location: Hurley, Mo Posts: 4,227	welcome to the boards, and, do you have a hotstart lever? idk whats wrong here. doesnt sound like a carb problem, but id go ahead and clean it anyways. that may help a little. are you using choke? how much? __________________ 2 strokes 2 wheels

02-20-2008, 04:32 PM	#3 (permalink)
turtlemann14 Pro Mototips Member Join Date: Oct 2007 Location: West Virginia Posts: 3,720	i would check the plug if you have not yet. sounds like it is fouling out __________________ If it does not move at first, get a bigger hammer!! Myspace Kawasaki z1 900 1973 rake extended, big bore block 1127cc, carbs, straight pipe exhaust, coils, and new paint job Kawasaki klx250 1979 custom fiberglass silencer+ Honda xr200r 1985 stock = Dakaw Dk250 2008

02-20-2008, 06:43 PM	#4 (permalink)
wr250f95 Super Moderator Join Date: May 2007 Location: New Mexico Posts: 7,418	what have you been mixing your gas at? __________________ "LIFE'S JOURNEY IS NOT TO ARRIVE AT THE GRAVE SAFELY IN A WELL PRESERVED BODY, BUT RATHER TO SKID IN SIDEWAYS, TOTALLY WORN OUT, SHOUTING'...HOLY S**T... WHAT A RIDE!" this, is why I ride.

02-20-2008, 08:45 PM	#5 (permalink)
tigmaster Administrator Join Date: Aug 2006 Location: Missouri, United States Posts: 7,240	2 strokes don't have hot start levers TJ. How did the old piston look? Any weird spots to it? Did you hone when you put the new piston in? How was the bore? Is your coolant system topped off? Like WR said, what is your gas mixture at right now? Have you changed the mixture? How did you break in the bike? Sorry for all the question but I am just getting the groundwork laid. __________________ --'03 CRF450r-- --FMF Pipe, Pro-Tech Revavle-- --Vortex Basket With Tusk Disks And HP Springs-- --Pro Taper Triple Clamps And Bars-- --Devol Full SP With Moose HGs-- --Renthal 13/50 With R1 Chain-- --Now It Is The End, Probably...-- --'06 CBR F4I-- --Bone Stock-- Check Our Latest How-To Here Last edited by tigmaster; 02-21-2008 at 10:25 AM.

02-20-2008, 08:55 PM	#6 (permalink)
tjscott2012 The Spam man Join Date: Nov 2007 Location: Hurley, Mo Posts: 4,227	its a 2t tig __________________ 2 strokes 2 wheels

02-20-2008, 09:28 PM	#7 (permalink)
gscx Pro Mototips Member Join Date: Aug 2007 Location: bridgeville DE Posts: 2,080	check the carburator, the pilot jet might be clogged up, and if it is nikasil plated you shouldnt hone it, but since it is older it is probly sleeved, and they do need to he honed befor you put a new piston in __________________ 2004 YZ-125 - PC exhaust, Blue applied triple tree, blue turner OV bars, ASV levers, Sunline sprocket and gold chain, FC springs, white plastic . DONT MESS WITH ME, I HAVE A HAMMER AND WILL USE IT!!!!!

02-21-2008, 10:29 AM	#8 (permalink)
tigmaster Administrator Join Date: Aug 2006 Location: Missouri, United States Posts: 7,240	I meant to say 2 stroke TJ. 2 strokes do not have a hot start lever. If the bike just happened to be Nikasil plated, scrub the bore out with a 3M pad ad soap and water. Its not that they shouldn't be honed, its simply that anything less than a diamond tipped hone is not going to even touch it. However, never use a ball hone on a 2 stroke, always use the 3 stone hone. Did the bike ever bog when you revved it from an idle? We you ever rolling, idling along and gave it gas to have it bog? Did it ever bog at low engine RPM's? If you answered no to all of these then the pilot jet is fine but cleaning you carburetor is something you may want to do anyways. __________________ --'03 CRF450r-- --FMF Pipe, Pro-Tech Revavle-- --Vortex Basket With Tusk Disks And HP Springs-- --Pro Taper Triple Clamps And Bars-- --Devol Full SP With Moose HGs-- --Renthal 13/50 With R1 Chain-- --Now It Is The End, Probably...-- --'06 CBR F4I-- --Bone Stock-- Check Our Latest How-To Here

02-21-2008, 02:04 PM	#9 (permalink)
gscx Pro Mototips Member Join Date: Aug 2007 Location: bridgeville DE Posts: 2,080	it might be plated, but im not sure, i do know that a 96 rm250 that i have is plated but anything older might not be __________________ 2004 YZ-125 - PC exhaust, Blue applied triple tree, blue turner OV bars, ASV levers, Sunline sprocket and gold chain, FC springs, white plastic . DONT MESS WITH ME, I HAVE A HAMMER AND WILL USE IT!!!!!

02-21-2008, 02:37 PM	#10 (permalink)
tjscott2012 The Spam man Join Date: Nov 2007 Location: Hurley, Mo Posts: 4,227	im confused, whats a hot start do again? __________________ 2 strokes 2 wheels

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