ninjette.org - View Single Post - What octane gas do big bore high compression guys run?

Bob KellyIII · January 13th, 2023, 07:48 PM

But you are not looking at the stress factor you are adding when you increase the compression ratio .
if you want a reliable bike this is a major consideration...
Typically when increasing compression ratios on big V-8's the mechanics usually change the connecting rods for stronger ones this is necessary to keep the engine from blowing up and destroying itself...
for just a few percent change in compression ratio obviously this is not a concern but consider what it is also doing to the main bearings....so now instead of the main bearings being hit with a 1lb hammer every time the piston fires it is being hit with a 1.75lb hammer every time....a small change in compression ratio changes to a large change in the main bearings and connecting rods.......
you obviously know this, but seem to be disregarding it as a non-issue...
let me assure you it is not a non-issue!
Bob....

January 13th, 2023, 07:48 PM	#16
Bob KellyIII Retired motorcycle Mc. Name: Robert Location: Weed, California. Join Date: Jul 2021 Motorcycle(s): 2012 Kawasaki Ninja 250R, 2021 CSC TT250, 1977 Triumph Bonneville 750cc,2001 Honda XR650L. Posts: A lot.	But you are not looking at the stress factor you are adding when you increase the compression ratio . if you want a reliable bike this is a major consideration... Typically when increasing compression ratios on big V-8's the mechanics usually change the connecting rods for stronger ones this is necessary to keep the engine from blowing up and destroying itself... for just a few percent change in compression ratio obviously this is not a concern but consider what it is also doing to the main bearings....so now instead of the main bearings being hit with a 1lb hammer every time the piston fires it is being hit with a 1.75lb hammer every time....a small change in compression ratio changes to a large change in the main bearings and connecting rods....... you obviously know this, but seem to be disregarding it as a non-issue... let me assure you it is not a non-issue! Bob.... __________________________________________________ Its too late when you've gone too far !