52mm rings fit an old 2" Homelite bore?

[777funk]

I'm thinking I can take a little off of the ring gap and get them to fit (52mm = 2.047"). Would this be likely t work? Seems like there are plenty of 52mm chainsaw rings available in the correct width.

 

[RedneckChainsawRepair]

Long as same thickness and real close to same. Lot of us has had to file rings to fit other saws if they are close to fitting.

Rings go NLA. Also if you know specs of ring them come with you might find rings from another maker that dont need filed.

Done that alot and way easier.

 

[Mad Professor]

You should be able to find Cabers that fit. Get your calipers out then go to their website.

 

[Vintage Engine Repairs]

I'm thinking I can take a little off of the ring gap and get them to fit (52mm = 2.047"). Would this be likely t work? Seems like there are plenty of 52mm chainsaw rings available in the correct width.

Unfortunately it’s more in depth than that. Having machined a set of piston rings from scratch for a 70cc 2 stroke there are a number of clearances to consider. If anyone of them are wrong you’ll cause damage.

You need to account for ring end gap (as you mentioned), ring to ring land clearance, back clearance, ring width and thickness, profile / shape of the alignment pin etc.

 

[Sidecarflip]

Though I don't normally fiddle with 2 stroke engines internally, SOP for me on any 4 stroke motor, diesel or gas is filing / grinding the ring end gap to specification. I always check and verify end gap prior to installing a slug in a bore.

Too large and the rings will pass an excessive amount of compression and too small will promote scoring of the bore and in extreme cases, will make it difficult to install the slug in the bore itself. In a 4 stroke engine, that is referred to as 'blowby' In a 2 stroke it's referred to as loss of initial compression (I presume) Engine builders will always specify ring gap in the specifications in their manuals.