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John Healy, JubeePrince, Lorenzo
Total Likes: 3
Original Post (Thread Starter)
by Bob Fletcher
Bob Fletcher
I have 3 sets of Triumph Twin 750 pistons -- all different top shapes and heights-- is there a diagram somewhere that will detail what compression ratio they are by measuring the height from the wrist pin centers to the top of the pistons? I have a Glenn's Triumph Guide that shows this very well for 650 pistons on page 75---but nothing for 750's------ and-- is the 7.9 compression ratio what I should be building my engine with for normal street use? What other options of low compression pistons are there to choose from? Some of the piston sets are Routts TRW 403-99 pistons. The Routts look to be heavy duty pistons for racing?
Liked Replies
by L.A.B.
Originally Posted by John Harvey
don't think there was anything available lower than the 7.9:1 option.

Also 7.4:1 (71-7085)
2 members like this
by Bob Fletcher
Bob Fletcher
I have ordered some new pistons -- after I receive them I will have enough data to put out here everything I know about comparing piston crown heights to compression ratio's---inquiring minds want to know!-- stay tuned
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