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Rebuilding the engine all assembled, and although done a re-build many times and I’ve no reason to doubt myself but is there anyway you can check if the rings are located correctly on the pegs, just the nagging doubt probably for no reason.

Jeff t wrote:Rebuilding the engine all assembled, and although done a re-build many times and I’ve no reason to doubt myself but is there anyway you can check if the rings are located correctly on the pegs, just the nagging doubt probably for no reason.

Some piston's have a poor history with ring pegs coming loose due to heat.

Which piston do you have?

Quattrini, its because you can’t obviously see it although the ring does look to be seated ok when you look through the exhaust or intake port.

If I get this right Jeff, you do not suspect ring peg failure, but you are concerned that the rings may not have seated correctly during the rebuild?

If you don’t seat the rings correctly, then the piston won’t fit into the barrel (unless it is very worn).

Does that help?

Yes exactly that, thanks that’s what I thought but thanks for confirming and as it’s brand new and moves as it should then should be right.

As Knowledge stated, it would be impossible to assemble the piston to the barrel.

Even with badly worn rings &/or bore, without being totally hamfisted, & breaking things during the process, the only way the fit would be achieved was if the pegs were virtually worn out (with very little depth of peg remaining) or if they were loose in the locating holes & could be pushed through, or further inwards, toward the inside of the piston.

I doubt very much that MQ would produce pistons like that, but where other's manufacture any 'Lambretta specific' items with no quality control or plain common sense, you need to be careful what you are buying into

Chains & rear hub bearings with pop in/pop out plastic cages spring to mind.....