RM250 dies when hot

JGroves · 09-20-2012, 04:16 PM

nt

anotherguy · 09-20-2012, 06:29 PM

Coil or CDI box.

SM Crank · 10-20-2012, 12:07 PM

Strip the carb, sounds like it pulled some crap out of the bottom of the tank when you ran it dry.

Happened to me!

anotherguy · 10-20-2012, 03:11 PM

You can start the bike,let it idle and heat the CDI or coil with a hair dryer and see if it fails when it gets hot. Don't overdo the heat you can kill the component.

PSchrauber · 10-20-2012, 03:28 PM

I guess when you simply replace the plug the bike will run again.

third eye · 11-16-2012, 07:47 AM

I would totally go through the entire fuel system and make sure everything is cleaned out.

Shocktower · 11-17-2012, 03:07 AM

Quote:

Originally Posted by third eye

I would totally go through the entire fuel system and make sure everything is cleaned out.

And since it's got some age on it I would also put a new set of main seals, probably worth the 16-20 bucks instead of the 200+ to rebuild a blown up 2 stroke, also claean the carb, i am pretty sure the piliot jet is gummed up too JMHO

wfopete · 11-17-2012, 04:17 AM

Ditto on what has been said. Moving targets can drive you nuts. Most likley the fuel system but maybe not. Start with the basics first (fuel, comp., spark). Check the grounds for your ignition!!! It's an old bike and corrosion can be everywhere. Clean, tighten bolts, screws, put on lock washers to get a good bite into the frame. Might as well move on to a Comp. test or leakdown test before diving into the crank seals. If it turns out to be crank seals or ignition labor and parts may not be worth the fix. If you need new ignition parts, OEM can be SOL. A PVL or other after market ignitions can be upwards of $500!

Good luck.

4badboyz · 11-17-2012, 05:22 AM

had the same kind of issue with my cr250 until I changed the coil. very frustrating to figure out.

RodT · 11-17-2012, 08:55 AM

just a thought, check the tank vent, sometimes this is the problem. I had a new ski-doo, and it would run fine for a little while and die, would not start until it sat for a while. It finally siezed the motor and that's when we found the vent tube was kinked . caused a serious lean condition.

larryboy · 11-17-2012, 09:02 AM

Uhm, you ran a two stroke out of fuel...in other words, without lube for the piston. Melted rings and a scored bore is my bet.

RodT · 11-20-2012, 08:33 PM

I hope you are kidding ??? I run chainsaws for a living and trust me, they run out of gas alot!!!!Runnig out of gas in a 2 stroke dosen't hurt a thing.

Quote:

Originally Posted by larryboy

Uhm, you ran a two stroke out of fuel...in other words, without lube for the piston. Melted rings and a scored bore is my bet.

motomark39 · 11-20-2012, 08:37 PM

Take it off, have it tested

D.T. · 11-21-2012, 04:00 PM

Yeah, what they said.

I'd pull the plug when it won't start and look for spark. I've seen the reisitors corrode in the caps too.

81cr450 · 11-24-2012, 08:49 AM

Cheap answer is always the best to try first

Strip the carb, sounds like it pulled some crap out of the bottom of the tank when you ran it dry.

"just a thought, check the tank vent, sometimes this is the problem. I had a new ski-doo, and it would run fine for a little while and die, would not start until it sat for a while. It finally siezed the motor and that's when we found the vent tube was kinked . caused a serious lean condition."

"I'd pull the plug when it won't start and look for spark. I've seen the reisitors corrode in the caps too."

In that order.

Old bike should really have fresh main seals, $20 for a flywheel puller, $20 seals. It dont cost a mint to ride old bikes just common sense & not throwing money away on guess's. Use the process of elimination on the cheaper fixes especially where you can get it to run. Should be a blast once you get it sorted, I sure wouldnt mind a 90's RMX250 myself

09-20-2012, 04:16 PM	#1
JGroves ^OP Late Joined: Nov 2005 Location: Home Oddometer: 149	RM250 dies when hot nt JGroves screwed with this post 02-01-2013 at 01:45 PM

09-20-2012, 06:29 PM	#2
anotherguy Beastly Adventurer Joined: Jun 2009 Location: in the foothills now.... Oddometer: 4,313	Coil or CDI box. __________________ When injustice becomes law,resistance becomes duty. Thomas Jefferson

10-20-2012, 03:11 PM	#4
anotherguy Beastly Adventurer Joined: Jun 2009 Location: in the foothills now.... Oddometer: 4,313	You can start the bike,let it idle and heat the CDI or coil with a hair dryer and see if it fails when it gets hot. Don't overdo the heat you can kill the component. __________________ When injustice becomes law,resistance becomes duty. Thomas Jefferson

11-17-2012, 04:17 AM	#8
wfopete Suffer Fools; Gladly! Joined: Aug 2004 Location: Somewhere North of Dover, AR Oddometer: 309	Ditto on what has been said. Moving targets can drive you nuts. Most likley the fuel system but maybe not. Start with the basics first (fuel, comp., spark). Check the grounds for your ignition!!! It's an old bike and corrosion can be everywhere. Clean, tighten bolts, screws, put on lock washers to get a good bite into the frame. Might as well move on to a Comp. test or leakdown test before diving into the crank seals. If it turns out to be crank seals or ignition labor and parts may not be worth the fix. If you need new ignition parts, OEM can be SOL. A PVL or other after market ignitions can be upwards of $500! Good luck. __________________ *Suffer Fools; Gladly!*

11-17-2012, 05:22 AM	#9
4badboyz Studly Adventurer Joined: Mar 2010 Location: Oakville. Oddometer: 544	had the same kind of issue with my cr250 until I changed the coil. very frustrating to figure out. __________________ tuck in behind me, I'll show you where to crash. 06KTM950A 07KTM525EXC 03CR250R 77RD400 Yet another Translab report... Owen and Mark do Labrador Moab 2012

10-20-2012, 12:07 PM	#3
SM Crank n00b Joined: Jun 2012 Oddometer: 6	Strip the carb, sounds like it pulled some crap out of the bottom of the tank when you ran it dry. Happened to me!

10-20-2012, 03:28 PM	#5
PSchrauber Studly Adventurer Joined: Jan 2011 Location: Summer: Kemiö, Finland; Winter: North Germany Oddometer: 641	I guess when you simply replace the plug the bike will run again.

11-16-2012, 07:47 AM	#6
third eye Adventurer Joined: Sep 2010 Location: Concord, CA Oddometer: 48	I would totally go through the entire fuel system and make sure everything is cleaned out.

11-17-2012, 08:55 AM	#10
RodT Gnarly Adventurer Joined: Sep 2008 Location: Westwood, CA. Oddometer: 289	tank vent just a thought, check the tank vent, sometimes this is the problem. I had a new ski-doo, and it would run fine for a little while and die, would not start until it sat for a while. It finally siezed the motor and that's when we found the vent tube was kinked . caused a serious lean condition. __________________ Any fool can criticize,condem and complain and most fools do. Ben Franklin RodT screwed with this post 11-20-2012 at 08:37 PM

11-17-2012, 09:02 AM	#11
larryboy Paint it black. Joined: Jan 2005 Location: Über Alles,Ca Oddometer: 12,855	Uhm, you ran a two stroke out of fuel...in other words, without lube for the piston. Melted rings and a scored bore is my bet.

11-20-2012, 08:37 PM	#13
motomark39 I reckon so Joined: Feb 2007 Location: Odenville, Alabama Oddometer: 1,035	coil...... Take it off, have it tested __________________ 2006 KTM 640 Adventure 2013 HusabergTE300

11-21-2012, 04:00 PM	#14
D.T. One wheel wonder... Joined: Aug 2004 Location: Moneyapolis, MN Oddometer: 6,287	Yeah, what they said. I'd pull the plug when it won't start and look for spark. I've seen the reisitors corrode in the caps too. __________________ "Tough times don't last, but tough people do." Robert A. Schuler

11-24-2012, 08:49 AM	#15
81cr450 Adventurer Joined: Jul 2011 Location: Piute ATV trails Utah , Dreaming of Baja Oddometer: 57	Cheap answer is always the best to try first Strip the carb, sounds like it pulled some crap out of the bottom of the tank when you ran it dry. "just a thought, check the tank vent, sometimes this is the problem. I had a new ski-doo, and it would run fine for a little while and die, would not start until it sat for a while. It finally siezed the motor and that's when we found the vent tube was kinked . caused a serious lean condition." "I'd pull the plug when it won't start and look for spark. I've seen the reisitors corrode in the caps too." In that order. Old bike should really have fresh main seals, $20 for a flywheel puller, $20 seals. It dont cost a mint to ride old bikes just common sense & not throwing money away on guess's. Use the process of elimination on the cheaper fixes especially where you can get it to run. Should be a blast once you get it sorted, I sure wouldnt mind a 90's RMX250 myself

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