kickstarter Jammed 05 yz250

Went out riding and the kick starter stuck like the engine seized, will start bump starting. After bump starting kick starter freed up then froze again, and this process works every time. Kick starter is smooth until the clutch basket is installed. I can turn the engine over by turning the clutch basket, but not with the kick starter. All gears turn smoothly.

I have a race this sunday please help:worthy:

Is the clutch maybe engaging while kicking it? Sounds strange, not sure if a locked up clutch would cause that. Just wondering, I hope you figure it out. And I'd like to know what's causing it for future reference.

Make sure the idler between the kick axle and the clutch is seated and the washer or shim and snap ring are in place....I just went through this on mine.

I'm helping him with his bike, with the clutch basket removed you can smoothly kick it (with hand) but when you install the basket(with no plates in) you can only push it down once and then the kick starter freezes up. I can turn the engine over by grabbing the basket and spinning it hard and that actually frees up the kick starter for one kick but then it locks up again. With no basket it can be pushed smoothly a 100 times its just as soon as the basket is installed it gets this issue.

Pull the idler between the kick axle and clutch basket out.....see if it still does it. If it goes away, make sure you reinstall the idler with no shin under it and not upside down.

Fire away with some pics when you pull it down.

any ideas?

Did any disassembly/reassembly precede this problem? If so, that's what caused it. If not, then:

http://parts.yamaha-motor.com/partimage.gifx?d=105190,2,0,sport

Is number 14 installed like shown? Will everything rotate correctly if entire kick assembly is removed? Sounds to me like either clutch basket is binding on something (doubtful) number 14, from above has the shims/clip in the wrong order, doubtful if not taken apart recently, or something within the kick assembly itself is messed up, including the hole in the inner case and the one in the outer case where it comes through. I'd go with the last if it has not been apart recently. I would also check that there is no end play on either transmission shaft, as if they are walking back and forth, all sorts of nasty things happen, and the kickstarter could just be a symptom.

Numer 11 likes to come loose as well. or case damaged at this point, bent, etc.

bike ran for a good 10hours probably after the kick start ratchet was replaced. number 14 has never been removed, spins freely and is installed like shown. I checked the stopper and its fine. With right side case off and basket installed, when we do get the kick starter to go down it really doesn't return to the stopper as quick as it does with no basket, its like it gets held up on the last last few mm's of return.

bike ran for a good 10hours probably after the kick start ratchet was replaced. number 14 has never been removed, spins freely and is installed like shown. I checked the stopper and its fine. With right side case off and basket installed, when we do get the kick starter to go down it really doesn't return to the stopper as quick as it does with no basket, its like it gets held up on the last last few mm's of return.

How about one more turn of the spring? Could you have that one wrap too loose?

Burrs/distortion in holes where kickstarter go?

Something incorrect/debris in kickstarter area that was worked on?

relationship of number 4 to shaft: is it off a few teeth? I take it that this is what was replaced.

Again, this usually happens (to all of us, sooner or later) after something has been apart.

I made sure the spring was wound correctly, there were no visible burrs or debris. Yes it was number 4 that was replaced I'll have to look again at the relationship between that and the shaft, I put it on the same way that I took it off and the bikes been running really good for over a month of riding every weekend. Hopefully its an easy fix.

R.I.P. LazyWaffleman's motor

What happened?

Maybe he'll post pictures later, about 25% of his piston skirt is missing ,needs new crank and cylinder plated also. Kind of hard to believe it still ran.

I've been away from two strokes for a while, but it sure seems people go through a lot of pistons and cylinders these days. I used to get several seasons out of my YZs that weren't raced. I had a YZ400 (two stroke) that ran for eight years with the same Wiseco, and it wasn't babied.I used it hard as a woods bike, lots of sustained full throttle top gear stuff, never a problem. Oil not up to it, or poor gas?

I've been away from two strokes for a while, but it sure seems people go through a lot of pistons and cylinders these days. I used to get several seasons out of my YZs that weren't raced. I had a YZ400 (two stroke) that ran for eight years with the same Wiseco, and it wasn't babied.I used it hard as a woods bike, lots of sustained full throttle top gear stuff, never a problem. Oil not up to it, or poor gas?

Not sure, my 2 strokes have been good to me, I went 500hours on a 125 top end(i was young and didn't know how to do a top end), I only changed it because I was scared something would blow up.Engine ran strong until the next owner blew it up.

I know whats jamming the kickstarter!

The cylinder plating is worn out, connecting rod has alot of play in it and the piston cracked. I need a new crank, connecting rod, piston, cylinder, crank bearings and seals. On top of that i have a new clutch as the last on got toasted by this issue.

Its kind of a bad picture, the intake side has the broken skirt.

224698_215891445088827_100000039184531_884316_7794507_n.jpg

I think I just felt my wallet get alot lighter :thumbsup::thumbsup:

Yeah, that's a lot of bucks going to the replacement parts. That shot looks like there's little to no oil. What gives? I'd expect to see quite a bit. Be sure to check the port chamfering on the new bore, the piston must have been caught in the port at least a little. I don't see any scuff marks in the photo, but pistons don't just break because "today's the day;" oil, piston fit/port edges, detonation, jetting. One of those got your piston, or a combination of all.

There's a lot of discussion on here about having your 250 converted by Eric Gore to a 300. Maybe that's the way you want to go. More displacement means less need to use full throttle on an extended basis. If you're not running sanctioned races, you could do that.

Yeah, that's a lot of bucks going to the replacement parts. That shot looks like there's little to no oil. What gives? I'd expect to see quite a bit. Be sure to check the port chamfering on the new bore, the piston must have been caught in the port at least a little. I don't see any scuff marks in the photo, but pistons don't just break because "today's the day;" oil, piston fit/port edges, detonation, jetting. One of those got your piston, or a combination of all.

There's a lot of discussion on here about having your 250 converted by Eric Gore to a 300. Maybe that's the way you want to go. More displacement means less need to use full throttle on an extended basis. If you're not running sanctioned races, you could do that.

The plating is completely worn away on the ports of the cylinder. I think it was just a combination of very worn out parts.

I am thinking about sending the cylinder out to get the 300 but it would just add to the cost of the rebuild. At this point im thinking the stock bore is the option im going with.

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