Author Topic: T35 piston rongs  (Read 1026 times)

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Offline CooperS

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T35 piston rongs
« on: 28 Oct 2018 at 18:39 »
 Boy does it get complicated when you are dealing with 70 year old bikes

Please correct me if I am wrong

It seems pistons changed in 1948 (later marks) from high dome pistons with 60.8mm x 4 mm wide oil scraper rings to flat top pistons with 3/32 wide scraper rings.
The original pistons from the engine (seized and buggered) have 4mm wide rings (they gap at 1/16 in the new bores).
My new pistons are a mistery, they have 1/8 (3.2mm). Oil scraper rings.

I cannot source 1/8 wide rings anywhere but could get 2 made at great expense.
Could anyone suggest where I could get a pair, 4mm x 60.8 STD would suit and I will machine out the ring groove.

Offline eddie

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Re: T35 piston rongs
« Reply #1 on: 29 Oct 2018 at 07:17 »
4mm x 60.8 rings were also used in the Douglas Dragonfly.
  Some of the pistons in the early postwar T35's had two 1/16" wide rings in 1/8" grooves.