Author Topic: rocker ratio?  (Read 1136 times)

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Offline bwaller

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rocker ratio?
« on: January 20, 2015, 04:28:08 PM »
Does anyone know the rocker arm ratio for the CB500/550/650's?

Offline bwaller

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Re: rocker ratio?
« Reply #1 on: January 20, 2015, 05:05:15 PM »
I searched around and found a value of 1.1:1, but it isn't discussed much because we have no aftermarket options.
So if any clear-headed individual would verify my logic here's my plan.  ;D I have my notes on valve lifts.

So if I spin a cam and indicate lobe height from base circle then divide into my valve lift, the result should be the arm ratio??

Offline FunJimmy

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Re: rocker ratio?
« Reply #2 on: January 20, 2015, 11:10:16 PM »
So if I spin a cam and indicate lobe height from base circle then divide into my valve lift, the result should be the arm ratio??

Correct.

eg: if you measure 0.500" of valve lift and the lobe height (from base circle to highest point) of 0.300" then 0.500" divided by 0.300" = 1.666 rocker ratio.

The trick is......can you find different ratio rockers?
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Offline bwaller

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Re: rocker ratio?
« Reply #3 on: January 21, 2015, 05:45:12 AM »
So I average 1.08 on the intake side, a little less @ 1.07 exhaust. Has that 1.1 value just been rounded up?...don't know.

I only have 8 welded rockers to choose from Jimmy, maybe I should have gone through that exercise earlier in the process.