Is this cylinder wall okay?
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my67xr
Miniriders Legend and Master Spanner Spinning Mode
looking at the valve seats you can see some darker patches, where the carbon had built up.
how much was on the back of the valves ?
i would clean it up with some 0000 steel wool, (the finest grade) Bunnings sell a small (50g) pack for under $7
give it a good degrease and blow it all out, do it a couple of times to remove any of the steel wool fibres left.
then reassemble it and try it out.
otherwise you need to replace the valve guides, and that will need the seat to be recut then too
how much was on the back of the valves ?
i would clean it up with some 0000 steel wool, (the finest grade) Bunnings sell a small (50g) pack for under $7
give it a good degrease and blow it all out, do it a couple of times to remove any of the steel wool fibres left.
then reassemble it and try it out.
otherwise you need to replace the valve guides, and that will need the seat to be recut then too
Check page 2 for pics of the valves.
I would personally say a fair bit?
I honestly think this build up might be the reason for the compression loss..
I've got the valves sitting in a tub of engine degreaser tonight so I'll have a crack at cleaning them up tomorrow then put the bike back together and test it. If it's still no good I'll buy a leak down tester and see where it's leaking from.
Thanks for all the help lads!
Sent from my GT-I9300T using Tapatalk
Quick update:
Finally got the time to clean everything up..
Both the valve seats and faces came up amazingly and i'm quietly confident that is the problem with the compression loss.
I measured the piston end ring gaps and only 2nd ring was .05mm out of spec (wide).
Piston skirt is in spec and in decent condition I think, not too much scuffing like on the cylinder.
No carbon built up around or near any of the rings and a lot of that crap on top of the piston just rubbed off with a rag.
Finally got the time to clean everything up..
Both the valve seats and faces came up amazingly and i'm quietly confident that is the problem with the compression loss.
I measured the piston end ring gaps and only 2nd ring was .05mm out of spec (wide).
Piston skirt is in spec and in decent condition I think, not too much scuffing like on the cylinder.
No carbon built up around or near any of the rings and a lot of that crap on top of the piston just rubbed off with a rag.