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trouble starting yz250

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my yz 250 wont start cold without a tiny shot of starting fluid. but once it has started that one time it is fine the rest of the day as long as its still warmish. any ideas on how to fix this?

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I just went through the carb completely a couple weeks ago and it was pretty spotless, I will pull the top end as soon as I can maybe tonight and see what I can see, what should I be looking for in there exactly?

 

You really should pull the top end and have a look at what you're dealing with. I'd also look at the carb.

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Unscrew the choke assembly and make sure its flushed out and/or functional? Maybe as simple as that. And even if the pilot looks clean it may be corroded from sitting. If pick up a new 50, maybe one up one down too

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Unscrew the choke assembly and make sure its flushed out and/or functional? Maybe as simple as that. And even if the pilot looks clean it may be corroded from sitting. If pick up a new 50, maybe one up one down too

ill do that tomorrow, cant get a new jet til Monday so I guess thatll have to wait, but ill do the choke tomorrow and see what it looks like.

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Sorry for my absence, repairs on my truck took priority over my toy for a while, but now I am back and with pictures of the results of taking the piston out and a look at the jug. the piston is toast, replacing anyway, the cylinder looks a little scored and scratched too though and I am hoping I don't need a bore. it is already a 68.5 mm bore. that's .5 mm over. what are y'alls  thoughts on the boring/ honing of the cylinder? thanks in advance!

 

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That cylinder is destroyed.  You need a bore and replate without a doubt.  That thing has seen a lot of abuse and under maintenance.

Edited by BiggestDog

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Sorry for my absence, repairs on my truck took priority over my toy for a while, but now I am back and with pictures of the results of taking the piston out and a look at the jug. the piston is toast, replacing anyway, the cylinder looks a little scored and scratched too though and I am hoping I don't need a bore. it is already a 68.5 mm bore. that's .5 mm over. what are y'alls  thoughts on the boring/ honing of the cylinder? thanks in advance!

 

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Mama mia! Yes, it needs some TLC, and unfortunately some $$ put into it. BTW, at 7700 feet, you might want to double-check the needed jetting, as you might be running it too fat...

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any ideas on the cost to get it bored? I am not familiar with plating, what is it ?? sorry if that's a dumb question, im more of a truck and four stroke guy, this is my first two stroke.

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Mama mia! Yes, it needs some TLC, and unfortunately some $$ put into it. BTW, at 7700 feet, you might want to double-check the needed jetting, as you might be running it too fat...

I had the shop check the jetting and they said they fixed it for this elevation,

 

That cylinder is destroyed.  You need a bore and replate without a doubt.  That thing has seen a lot of abuse and under maintenance.

what is replating? if your meaning like nikisil ( sorry if I spelled it wrong) I don't knw if this old of a bike would have it. just a thought though, I am kinda learning as I go. the scratches are less than a half mm deep it appears so do you think I could just bore it ? im taking the cylinder to the local shop today to see what they say too, ill keep yall posted. thanks for all the replies! keep em coming!

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any ideas on the cost to get it bored? I am not familiar with plating, what is it ?? sorry if that's a dumb question, im more of a truck and four stroke guy, this is my first two stroke.

 

 

Call Millennium Technology for cost.

 

It's about the only place that will do it.

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The pilot jet seems very large for that elevation to me

 

they rejetted it, I don't know what to though, I forgot.

 

Call Millennium Technology for cost.

 

It's about the only place that will do it.

 

I researched and the 89 was the last year that they didn't use plating, so I can just bore it out some more supposidley, does that sound right? I have a shop here that can bore it, so unless I have miss researched I think I canjust have it bored.

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That cylinder is destroyed.  You need a bore and replate without a doubt.  That thing has seen a lot of abuse and under maintenance.

the shop said it has been sleeved with an iron sleeve or something like that, so they are just gonna bore it out another .5 mm, they quoted $150 just to bore.. plus 200 for a piston and gasket kit so my 600 piece of crap just turned into a 950 dollar piece of crap that runs :banghead:

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