Pistion Replacement

**Sully60** · 21st February 2008, 15:48

Originally Posted by Ocean1

Changed the base gasket?

That wouldn't change the skirt to web clearance.

**quallman1234** · 21st February 2008, 15:49

Originally Posted by boostin

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.

Yes the there is an arrow on top. I put the pistion in so its facing the exhaust port with this arrow.

**quallman1234** · 21st February 2008, 15:51

Originally Posted by Ocean1

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

No no! lol, it fits fine in the cylinder. I took the cylinder off when it got siezed on the crank. i thought i broke a ring but it appeared that it was stuck on the crank and i couldn't turn it over. I took the pistion out and it turned over.

**FROSTY:Me** · 21st February 2008, 16:00

Humour an old(er) man. Grab the conrod with the crank at TDC -try to lift the bike with it.--Is there a clunk?

**quallman1234** · 21st February 2008, 16:02

Well i figured it out.

Now taking guesses'

**quallman1234** · 21st February 2008, 16:02

Originally Posted by FROSTY

Humour an old(er) man. Grab the conrod with the crank at TDC -try to lift the bike with it.--Is there a clunk?

Big end still ok.

**Ocean1** · 21st February 2008, 16:03

Originally Posted by Sully60

That wouldn't change the skirt to web clearance.

No, old memory of a base gasket fouling a piston many years ago.

Originally Posted by quallman1234

No no! lol, it fits fine in the cylinder. I took the cylinder off when it got siezed on the crank. i thought i broke a ring but it appeared that it was stuck on the crank and i couldn't turn it over. I took the pistion out and it turned over.

Dunno dude, got me fookt.

How much side-play is there in the piston on the gudgeon? Does it help if you centralise it?

**quallman1234** · 21st February 2008, 16:04

Well ill give it a way. It appears that on a AX100, The arrow on the crown should face backwards?

**Ocean1** · 21st February 2008, 16:06

Originally Posted by quallman1234

Well ill give it a way. It appears that on a AX100, The arrow on the crown should face backwards?

Well I'll be fookt...

**quallman1234** · 21st February 2008, 16:07

Sorry nevermind i take that back gahhh. Im doing this as well speak. Ill try my old pistion now. Sorry ocean. Ill try it with the cylinder on as well maybe its just me holding it at a funny angle whilst turning it over.

**Sully60** · 21st February 2008, 16:08

Originally Posted by quallman1234

Well ill give it a way. It appears that on a AX100, The arrow on the crown should face backwards?

That would have had me too!
An "in" would have been helpful!

Do the piston ports look a bit closer to where they should be now?

**Ocean1** · 21st February 2008, 16:12

Originally Posted by quallman1234

Sorry nevermind i take that back gahhh. Im doing this as well speak. Ill try my old pistion now. Sorry ocean. Ill try it with the cylinder on as well maybe its just me holding it at a funny angle whilst turning it over.

Gota hold yer tongue right mate.

**quallman1234** · 21st February 2008, 16:18

There appears to be a small piece of metal on the crank, right at the point where i think the pistion is hitting the crank. Shouldn't be any damage to the crank it self, because i only have lightly turned it over since my old pistion fucked it self. Yea too right i need to relax and not rush things.