Hard to start 2010 x31 when cold ???

Wickedness · 03-05-2012, 11:12 PM

Ok wise 250cc gurus! Figure this one out!? Bought this bike 2 weeks ago and was running when i picked it up, little bit of blue smoke on starting but nothing horrible seemed ok. Then 1 week later tried to start it and it took 10 mins of fighting with it to get it going. Blowed some blue and then went away.Ran fine. I figured id change the oil, used 10w40,replaced spark plug with de08r ngk, cleaned air filter and adjusted throttle cable.Took 10 mins to start blew less blue and ran awesome. Let cool overnight same thing 10 mins , took air filter off no diffrence. took spark plug out grounded it on exhaust and it has good spark. You can see gas on the plug and smell it out the muffler. Then i cranked the motor over without the spark plug in it. Put the plug back in and it fired right up!? Tried this with the stock spark plug and same thing, wont start cold unless you crank the motor with the plug out and then put it back in... boom instant start!? After its warm itll start and stop all the time perfectly! Any help with this issue would be much apperciated!!!! :(

MICRider · 03-06-2012, 12:07 AM

I'm wondering, what temps are you trying to start the bike in? I have a couple of GIO quads and they will start good to about 0 Celsius and then they get very contankerous, especially my sons 110 Mini Beast. It's almost like the gas doesn't atomize right and they flood out.

Weldangrind · 03-06-2012, 12:42 AM

Not a guru.

I agree with MICRider. I also think that the slow jet is just a little small for your application and temperature. I bet it would smarten up if it was warmer, but a larger slow jet would likely fix it.

Azriel_Strife · 03-06-2012, 01:13 AM

Just in case you aren;t aware, the choke operation is confusing to some. The choke in the down position is off.

I have to agree with Weld, I have an X31, and the jetting is all wrong for these bikes, they are jetted for a 150-200cc engine.

I believe the stock slow jet is a #36 slow jet, there is no place to buy replacements like these. Keihin slow jet part number N424-26 has been reported to work fine in these carbs. I reccomend you use a #40 slow jet.

as for your main jet, it's too small also, they seem to be a #88, but i'm not sure how that compares to an actual keihin jet. I'm running a keihin #130 right now and it's way rich. I'm not sure what jet size will work just yet, i have the parts on order and I will know soon enough what runs best. I have a hunch a jet somewhere in the 110 range will be about right.

Weldangrind · 03-06-2012, 10:18 AM

To complement Azriel_Strife's comments, the most reliable solution is to buy a Mikuni and install a 25 slow jet and 110 main. You can get a 30mm Mikuni for around $35 delievered, and jets are very easy to obtain.

In addition to the Mikuni being a good carb, you get the added bonus of being able to quantify jet changes with a system that makes sense. As an example, a 100 main jet is 1.00mm, a 110 jet is 1.10 mm and so on. Well worth it.

Wickedness · 03-06-2012, 07:27 PM

Wow! Thanks for the info! Im starting the bike in my heated garage at around 15-20 degrees c . It makes sense its the jetting because if you drop a little gas in the cilynder with the plug out it fires right quick. When i drained the gas tank it came out brownish yellow. The previous owner said it sat for a year. I put in premium gas. Its possible the jets are clogged with debris? Well anyway im just buying a new carb and suggested jets. Has anyone had a good experience with a performance cdi module?

MICRider · 03-06-2012, 07:50 PM

Ahh, it's in a heated garage, I was thinking it was outside... But, if it sat with old gas for about a year and the gas is brownish yellow I would definitely think it was the old gas. Probably did gum up your jets, a through cleaning will probably help a lot

.

FastDoc · 03-06-2012, 10:10 PM

I'd be inclined to use a short blast of ether and call it good.

Weldangrind · 03-07-2012, 12:43 AM

The performance CDI's have had mixed reviews. I think that the performance CDI on my Gio Beast quad made an improvement, but I can't quantify it.

X2 on cleaning the jets, but a new Mikuni is a better idea. :idea:

Wickedness · 03-07-2012, 04:26 PM

Thanks evreyone for your help! Im buying a new mikuni carb and keeping a bottle of quick start handy. I once blew the cylinder head right off a 8 hp snowblower with ether! When i was young we used it to start evreything at -35.c

Weldangrind · 03-07-2012, 09:24 PM

That sounds like a good reason to avoid ether. 8O

MICRider · 03-07-2012, 10:57 PM

Lol, speaking of ether we blew up an old combine with a flathead 6... Too much of a good thing can be a bad thing!

katoranger · 03-08-2012, 08:07 AM

I remember the Allis Chalmers tractor having a built in can of ether with a handle in the cab for cold starting. This would have been a late sixties early seventies model. 150hp farm tractor.

03-06-2012, 10:18 AM	#5
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	To complement Azriel_Strife's comments, the most reliable solution is to buy a Mikuni and install a 25 slow jet and 110 main. You can get a 30mm Mikuni for around $35 delievered, and jets are very easy to obtain. In addition to the Mikuni being a good carb, you get the added bonus of being able to quantify jet changes with a system that makes sense. As an example, a 100 main jet is 1.00mm, a 110 jet is 1.10 mm and so on. Well worth it. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

03-07-2012, 12:43 AM	#9
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	The performance CDI's have had mixed reviews. I think that the performance CDI on my Gio Beast quad made an improvement, but I can't quantify it. X2 on cleaning the jets, but a new Mikuni is a better idea. :idea: __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

03-07-2012, 09:24 PM	#11
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	That sounds like a good reason to avoid ether. 8O __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

03-05-2012, 11:12 PM	#1
Wickedness Join Date: Mar 2012 Posts: 3	Hard to start 2010 x31 when cold ??? Ok wise 250cc gurus! Figure this one out!? Bought this bike 2 weeks ago and was running when i picked it up, little bit of blue smoke on starting but nothing horrible seemed ok. Then 1 week later tried to start it and it took 10 mins of fighting with it to get it going. Blowed some blue and then went away.Ran fine. I figured id change the oil, used 10w40,replaced spark plug with de08r ngk, cleaned air filter and adjusted throttle cable.Took 10 mins to start blew less blue and ran awesome. Let cool overnight same thing 10 mins , took air filter off no diffrence. took spark plug out grounded it on exhaust and it has good spark. You can see gas on the plug and smell it out the muffler. Then i cranked the motor over without the spark plug in it. Put the plug back in and it fired right up!? Tried this with the stock spark plug and same thing, wont start cold unless you crank the motor with the plug out and then put it back in... boom instant start!? After its warm itll start and stop all the time perfectly! Any help with this issue would be much apperciated!!!! :(
	0

03-06-2012, 12:07 AM	#2
MICRider Join Date: Oct 2009 Location: Alberta, Canada Posts: 3,274	I'm wondering, what temps are you trying to start the bike in? I have a couple of GIO quads and they will start good to about 0 Celsius and then they get very contankerous, especially my sons 110 Mini Beast. It's almost like the gas doesn't atomize right and they flood out.
	0

03-06-2012, 12:42 AM	#3
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	Not a guru. I agree with MICRider. I also think that the slow jet is just a little small for your application and temperature. I bet it would smarten up if it was warmer, but a larger slow jet would likely fix it. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

03-06-2012, 01:13 AM	#4
Azriel_Strife Join Date: Mar 2012 Location: Chilliwack BC, Canada Posts: 32	Just in case you aren;t aware, the choke operation is confusing to some. The choke in the down position is off. I have to agree with Weld, I have an X31, and the jetting is all wrong for these bikes, they are jetted for a 150-200cc engine. I believe the stock slow jet is a #36 slow jet, there is no place to buy replacements like these. Keihin slow jet part number N424-26 has been reported to work fine in these carbs. I reccomend you use a #40 slow jet. as for your main jet, it's too small also, they seem to be a #88, but i'm not sure how that compares to an actual keihin jet. I'm running a keihin #130 right now and it's way rich. I'm not sure what jet size will work just yet, i have the parts on order and I will know soon enough what runs best. I have a hunch a jet somewhere in the 110 range will be about right.
	0

03-06-2012, 07:27 PM	#6
Wickedness Join Date: Mar 2012 Posts: 3	Wow! Thanks for the info! Im starting the bike in my heated garage at around 15-20 degrees c . It makes sense its the jetting because if you drop a little gas in the cilynder with the plug out it fires right quick. When i drained the gas tank it came out brownish yellow. The previous owner said it sat for a year. I put in premium gas. Its possible the jets are clogged with debris? Well anyway im just buying a new carb and suggested jets. Has anyone had a good experience with a performance cdi module?
	0

03-06-2012, 07:50 PM	#7
MICRider Join Date: Oct 2009 Location: Alberta, Canada Posts: 3,274	Ahh, it's in a heated garage, I was thinking it was outside... But, if it sat with old gas for about a year and the gas is brownish yellow I would definitely think it was the old gas. Probably did gum up your jets, a through cleaning will probably help a lot .
	0

03-06-2012, 10:10 PM	#8
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	I'd be inclined to use a short blast of ether and call it good. __________________ Happy to serve.
	0

03-07-2012, 04:26 PM	#10
Wickedness Join Date: Mar 2012 Posts: 3	Thanks evreyone for your help! Im buying a new mikuni carb and keeping a bottle of quick start handy. I once blew the cylinder head right off a 8 hp snowblower with ether! When i was young we used it to start evreything at -35.c
	0

03-07-2012, 10:57 PM	#12
MICRider Join Date: Oct 2009 Location: Alberta, Canada Posts: 3,274	Lol, speaking of ether we blew up an old combine with a flathead 6... Too much of a good thing can be a bad thing!
	0

03-08-2012, 08:07 AM	#13
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	I remember the Allis Chalmers tractor having a built in can of ether with a handle in the cab for cold starting. This would have been a late sixties early seventies model. 150hp farm tractor. __________________ You meet the nicest people on a Honda Clone.
	0