2005 yz250f broken kick start shaft

I will apologize for the lengthy post in advance. I am new to a thumper and need some help. I bought a used 05 yz250f about 6 months ago. Was having a tough time idling so I adjusted fuel screw as described by others here. Bike ran amazing! Actually raced a hare scramble at Carolina Adventure World and not a single problem. However...since then I noticed that there was fuel leaking from the bottom of the carb and it looked like it was coming from the fuel screw. Replaced with an adjustable fuel screw and set it back to the same setting (1 3/4 turns out). Also replaced the air filter (noticed that for some reason someone had two filters being used at once). Tried to crank the bike and could not get it to run. Would turn over and crank but not run. Tried small adjustments with the fuel screw in both directions and still couldn't get it to run. With all the kicking (past TDC and return to top and smooth kick) the kick start shaft broke inside the case. What are my options on the kick start, and what would cause it not to run after the changes I made? Oh...forgot to mention...I was planning on riding the little brown jug enduro next weekend...is that gonna be thrown out the window now?

Ok...so I'm on shift at the firehouse today and I took the bowl off the carb to do a little cleaning. Cleaned the jets (135 72 49...the 135 main just doesn't seem right!) just to be able to do some work to it. Carb is all cleaned up and it appears to still be leaking (probably need new gaskets). I'm still waiting on some of you thumper experts to chime in on all of this and give me some direction as to where to go from here. And the bike also has yoshimura exhaust. Any help will be greatly appreciated!

Dang...all the experience and knowledge on this site and nobody chimes in in three days! Guess I'm gonna be on my own for this one!

When you put the fuel screw in did it go oring, washer, spring, then screw? I lost the oring and didn't realize it until it started dripping.

um let see here

you need to replace the kick start shaft

and i would bet you have a fuel screw that does not have the same size tip as the one taken out.

measure from the threads to the end.

Yeah, the I put it in o ring, washer, spring. I think the leak is because the gasket on the bowl is worn out. My plan is to buy a rebuild kit for the carb and start the jetting from factory. (it seems to be jetted way low on the main jet (135 where stock is 168) and they had doubled the air filter so I'm trying to get it back where it should be. I also need input on replacing the kick shaft assembly! I'm hoping it's not something where I have to take half the bike apart.

um let see here

you need to replace the kick start shaft

and i would bet you have a fuel screw that does not have the same size tip as the one taken out.

measure from the threads to the end.

Measure from the threads to the tip or to the bottom where the knob is?

there is no such thing as a rebuild kit for the fcr.

you can buy parts for it (well some) and someone might put together a kit of these parts

but there is no official rebuild kit.

 

the knob is of no importance.

 

and a 168 was NEVER stock

 

you need to look in your manual because honestly from what you write, i dont think you can do this job.

there is no such thing as a rebuild kit for the fcr.

you can buy parts for it (well some) and someone might put together a kit of these parts

but there is no official rebuild kit.

the knob is of no importance.

and a 168 was NEVER stock

you need to look in your manual because honestly from what you write, i dont think you can do this job.

Well, since you are so knowledgable would you be inclined to say about what the stick jetting should be? And the kit I saw (may have been 'put together' as you say) but had new float, needle, jets, gaskets. If I would've better off not asking a question on this forum because I may not be as knowledgable as you then by all means let me know and I will go somewhere else. I have seen numerous people that seemed knowledgable and were willing to help...but from your response it seems like you only want to help the people you think know what they are talking about. I thought maybe someone would be nice enough to try to help...but the only thing I see is someone who just wants to bash what I said. And since you know so much why would someone have doubled the air filters. I'm just trying to get back running so I can ride and enjoy the bike...and hopefully I can learn a little bit about them along the way...but with comments like yours I doubt that I will ever learn anything.

You sure it was a double air filter, or was it a UNI air filter, which has two layers that are somewhat separate.

 

Far as the jetting, that sounds way out of whack....someone probably having no idea what they were doing. I don't know if you need to go back to factory, or view the Jetting D-base thread in this forum. Find some people with similar altitude/temps as you ride in, and see what they are saying. There are other variables in jetting then just those two, but its a start. I mean Im sure stock wouldnt be TOO far off, but it may not be "ideal" either.

Edited by J_WR2fitty

Thanks! That should help a lot to get it back to factory settings and then I can fine tune it from there! Anybody have any idea why there would be a 135 main jet and the air filters doubles?!

Sorry, I have no idea why someone would make that drastic of a change. Maybe they thought that doubling the filters would be better for the bike, then when it was running rich from air restriction they decided to put a smaller main jet in it. Good luck!

2 air filters? Like someone tucked one inside the other?

if I had a bike or anything  that ran

"  Bike ran amazing!"

 

I wouldn't start jacking around with jet changes just cause it wouldn't start after I messed with it

 

maybe thats just My way of thinking ?

You just pissed off one of your best sources of information (sUnruH) on this forum who just so happens to be also a mod. I'm betting its a UNI filter. It has likely a red filter outside with a yellowish foam filter inside.

the oem air filter (going back to 2001) looks like 2 filters, but it just 1.  it has 2 densities of foam.

or it could be a uni like many have listed above or another brand even.  if its bright yellow and black with no labels on it - oem.

 

ha ha no im not pissed off.  im laughing.

 

if you cant take the time to look in the manual, why should i help?

Well...I will look in the manual once I get one. Haven't had the bike long and it was actually running really good. I actually let a buddy race it while his husqvarna tc250 was in the shop and he said it was faster than his. I plan on starting to do all maintenance myself, but the bike took a dump on me the weekend before I was supposed to ride the little brown jug so I was hoping for some knowledgable advice to maybe get me back running before then. Sorry if I came off the wrong way, I was just in a pinch and I wanted to try and get it fixed. Doesn't look like I will have it fixed in time. Can't get the kick assembly quick enough to get a chance to change it.

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