Top-end rebuild KX65?

[oldguy]

Hi guys, I'm at the reassembly stage of a top end rebuild, of a KX65, I'm just after some advice on things I should lookout for and do as I put the top end back on. I'm at the stage were I am about to install the barrel.

1 The base gasket that came in the set is a paper type gasket, do I use a gasket cement or paste, the old one feels like a metal type.

2 when I torque down the barrel, should I do it in a crisscross way X or just torque in a clockwise direction.

3 does anyone know the torque settings for the barrel and head

4 Oh how would you go about running it in,

any help, advice appreciated.

cheers John

[Taz]

1. No just use the gasket as it is.
2. Doesnt really matter just do them up evenly
3. Torque - Just till ya elbow klicks Cyl head and barrel nuts 18 ft-lbs/25nm or 2.5kg-m
4. Run for a few minutes till she's warm stop and check for leaks etc. Run gently for a half hour or so then let rip.
Don't be too anal about torque settings, I'm sure you'll know when an 8mm thread nut is tight enough.
Andy.

[Taz]

Oh one other thing..... Ensure the rings are positioned properly on the piston as they have locating pins (just in case you didn't realise) and smear a little oil on the piston before sliding the barrel on.

[Katman]

My method of running in a new piston and rings is to continually blip the throttle once the engine is started for about five minutes. It gets the engine up to operating temperature and ensures a continually changing piston speed. Once warm, allow to cool down and then when restarted don't go thrashing it for the first 10-15 minutes.

[oldguy]

Thanks for the advice, help Anthrax, I'm no mechanic, but I like to have a go at doing it myself.
I did know about the locating pins on the piston, for the rings thanks.

[T.W.R]

1. No just use the gasket as it is.
2. Doesnt really matter just do them up evenly
3. Torque - Just till ya elbow klicks Cyl head and barrel nuts 18 ft-lbs/25nm or 2.5kg-m
4. Run for a few minutes till she's warm stop and check for leaks etc. Run gently for a half hour or so then let rip.
Don't be too anal about torque settings, I'm sure you'll know when an 8mm thread nut is tight enough.
Andy.

1) A fine smear of sealer (silastic etc) on either mating surface of the gasket is worthwhile to stop the gasket fusing to either the barrel or crankcase surfaces and fills in any imperfections on any of the surfaces.

2) tighten down to pinch tight then torque down in a cris-cross pattern; front left/rear right/front right/rear left. Eliminates pinching the gasket unnecessarily

4) vary the engine speeds for a while after it has had it's initial run & check for leaks

Make sure the pins locate definitely and smear pre-mix oil (not crankcase oil)in the bore of the barrel.

Question though: has the barrel been rebored or honed? if it's been rebored have the ports been chamfered? particularly around the bridge ports (exhaust side)

[oldguy]

1)
Question though: has the barrel been rebored or honed? if it's been rebored have the ports been chamfered? particularly around the bridge ports (exhaust side)

bore is in good nic, will just give a light hone.

[Katman]

The bore is electro plated. Unless you have a diamond hone you're wasting your time.

[oldguy]

The bore is electro plated. Unless you have a diamond hone you're wasting your time.

cheers for that.

[Henk]

I'd go aong with everything said here except the smearing oil around the barrel. When there is enough petrol for the bike to run there is enough oil to lubricate. I usualy put a thin smear on the small end bearing if it's a new one though.