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Author Topic: 70mph 4000rpm  (Read 1765 times)

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Offline neil10

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70mph 4000rpm
« on: February 02, 2008, 03:09:04 AM »
70mph 4000rpm  does that sound like standard gearing for k4 sohc 750   thks
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daniel son

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Re: 70mph 4000rpm
« Reply #1 on: February 02, 2008, 03:52:36 AM »
well my uk cb650z used to do 70mph at 6500rpm, but i changed the gearing so it now does 70mph at 4500rpm
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Offline KB02

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Re: 70mph 4000rpm
« Reply #2 on: February 02, 2008, 06:03:47 AM »
on my F1, I changed the stock gearing from 48 to 41 on the rear sprocket and I am now doing 4500 at 70 as well.

I would say the stock gearing has changed on your bike.
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daniel son

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Re: 70mph 4000rpm
« Reply #3 on: February 02, 2008, 06:58:34 AM »
same hear , i dropped 2 teeth at the rear sprocket(40 to 38) and went up 1 on the front(16 to 17).
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Offline andy750

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Re: 70mph 4000rpm
« Reply #4 on: February 02, 2008, 08:43:48 AM »
A stock CB750 (k2-k6) with 18/48 will usually run at 60mph/4000rpm in my experience.

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Andy
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Offline ofreen

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Re: 70mph 4000rpm
« Reply #5 on: February 02, 2008, 09:00:32 AM »
Quote from: neil10 on February 02, 2008, 03:09:04 AM
70mph 4000rpm  does that sound like standard gearing for k4 sohc 750   thks

Keep in mind that there could be significant error in either or both instruments.
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Greg
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Offline Gordon

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Re: 70mph 4000rpm
« Reply #6 on: February 02, 2008, 09:43:31 AM »
A more accurate way to determine your gearing would be to count the teeth on the sprockets. 
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