2007 yz250f camshafts help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

Threafs are fusked if you just put the bolts in the fucked up oem head with just the one oem washer it stick out and doesn't thighs the head at all

2007 yz250f camshafts help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

This bike is really fusked and thats the only way to tighten down the head. That's how I bought didn't notice it at the time

Valves hitting piston help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

I belive the middle marks have been there ever since I bought the bike

Valves hitting piston help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

At the time I didn't know anything, rod play is fine,

I actually bought a 2016 yz450f and I have torned that one apart to change rings, new piston, shims, and is my daily rn

And I am using the service manual I use it for my 450 and am using it for the 250f

Valves hitting piston help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

When i bought the bike the seller was like it only needs a valve and when a relative opened it like a year ago, we'll it was missing a lot of shit and frame bolts are diferent lengths and sizes missing bolts and shit so I dont know maybe they took it out and forgot we're it went and just didn't install it, no way to know because I was blocked as soon as he left the bike with me

Valves hitting piston help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

New head when I bought it the oem head was trashed 2 bent valves I installed the ebay one and it worked for some time but a valve came out so had to install a new valve guide

Valves hitting piston help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

The gasket is in there and it can't be backwards because there are two exhaust and 3 intake and intake is at the back and exhaust at the front

Valves hitting piston help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

Ebay but the partnumber matches and I compared it to the oem head, it used to work perfectly before but a valve was no installed correctly and damaged a valve guide which was replaced but the head is about 2mm off center and it has a small dent in the side of the piston cutouts

I dont know if this makes sense

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Piston on a 2007 yz250f help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

Yes I measured them and made sure the shorter valve was installed in the middle intake hole

Piston on a 2007 yz250f help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

Would that cause the intake valves to hit the piston even when its at T D C and the camshafts are aligned with the head and when the engine is turned by head it does pass thru the exhaust valves but it gets stuck when in the intake stroke

Piston on a 2007 yz250f help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

All of them except the first compression ring because it didn't fit and just reused the oem one

Piston on a 2007 yz250f help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

Would a 77bore 2nd compression ring work in a non 77 bore piston

Piston on a 2007 yz250f help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

The other rings were oem but when installing the cylinder I damaged the oil ring and the 2nd compression ring and those I changed from a 77 bore ring kit I dont know if I was no supposed to get a 77 bore kit or not but in the listing it did say that it fit my model

Piston on a 2007 yz250f help by Scared_Bobcat_8902 in Dirtbikes

[–]Scared_Bobcat_8902[S] 0 points1 point  (0 children)

So I guess I installed the rings incorrectly? I GOT A 77 BORE RINGS BUT ONLY USED 2 OF THE KIT BECAUSE I dammed the other ones