Pistion Replacement

[quallman1234]

I put my new pistion in, turned it over slowly and the pistion skirts got stuck on the crank? and stopped it from turning over. I pulled the pistion out and managed to save it all! and it still turns over now.

Did i do something wrong? Or is the skirt length too long?

[Sully60]

I put my new pistion in, turned it over slowly and the pistion skirts got stuck on the crank? and stopped it from turning over. I pulled the pistion out and managed to save it all! and it still turns over now.

Did i do something wrong? Or is the skirt length too long?

If the skirts to long the chick's the legs are probably too hairy!

Sounds like you've got the wrong piston son, better get a real good one i.e the proper one!

I would machine the skirt off if it was a 4T piston but I'd be checking that on a 2t. Ask F5Dave.

[quallman1234]

If the skirts to long the chick's the legs are probably too hairy!

Sounds like you've got the wrong piston son, better get a real good one i.e the proper one!

I would machine the skirt off if it was a 4T piston but I'd be checking that on a 2t. Ask F5Dave.

Hmm very odd considering it has "AX100" on the side of the box and thats what i ordered. I could easily get it sliced off a bit on a lathe at work. Im going to measure my old pistion and compare.

[Ocean1]

Stab in the dark... Is there an arrow or a wee triangle on the crown?

[boostin]

Hmm very odd considering it has "AX100" on the side of the box and thats what i ordered. I could easily get it sliced off a bit on a lathe at work. Im going to measure my old pistion and compare.

That is the strangest thing, I am putting my CB125t together right now and found exactly the same thing, just put the piston in the vice and waiting on a grinder to free up. Of course I know that these are not original pistons so I have been expecting something like this.

[boostin]

Stab in the dark... Is there an arrow or a wee triangle on the crown?

I assume that points to the front, right?

[Sully60]

Stab in the dark... Is there an arrow or a wee triangle on the crown?

Yeah, worth checking dude, the two sides of the piston could have different lengths. That's not at all unusual in an oil burner.

[Ocean1]

I assume that points to the front, right?

Never seen one pointing backwards...

[Sully60]

That is the strangest thing, I am putting my CB125t together right now and found exactly the same thing, just put the piston in the vice and waiting on a grinder to free up. Of course I know that these are not original pistons so I have been expecting something like this.

Are you using C70 pistons?

[Ocean1]

Sure it's the skirt hitting the crank?

Not the ring hooking up on the bottom of a port?

[boostin]

Are you using C70 pistons?

Yes...did you just watch me stab that screw driver into my thumb installing the C clips?

[quallman1234]

They measure up the same? Im going to go ahead and pop my old pistion in (Not using circlips - gotta save em hehe) and see if the same thing happens!

[quallman1234]

Sure it's the skirt hitting the crank?

Not the ring hooking up on the bottom of a port?

Def the skirt hitting the crank. Can't be the ring hitting the bottom of the port because the cylinders not even on it when i try it.

Note - I measured the length of the skirt and also the height of the hole for the guogen.

[Ocean1]

Ah, no cyl. Got to be the wrong piston dude...

[Sully60]

Yes...did you just watch me stab that screw driver into my thumb installing the C clips?

Done three big bore CB125s now. My first was with C70 pistons.
Have you machined the barrell to get the comprssion back to where it should be(ish) You'll need to take .8mm off the barrel height.
I thought mine went quite well then I got the comp right and BoYaa! She was a flyer.
I have found some pistons that make for a much easier conversion too BTW.
We just reassembled Skunks twin and it was the best(easiest) one I've done yet.