Page 1 of 1
rpm per mph
Posted: Sun Nov 20, 2016 11:15 pm
by DMC
Hi guys can anyone tell me how many mph your are doing per 1000 rpm with standard 2cv wheels running 135x15 tyres
not sure of gearing but i guess its standard 1979 dyane. If that helps. Cheers. Dave.
Re: rpm per mph
Posted: Mon Nov 21, 2016 7:54 pm
by Lomax76
Hi,
if I am no mistaken after conversion should be with AMI 8, Dyane gear box on 135x15 tyres 13,47mph for 1000 rpm
Speed max @75mph for 5580 rpm
Cheers
Re: rpm per mph
Posted: Mon Nov 21, 2016 9:15 pm
by howardjs
Hi, I have similar calculation...
Assuming your tyres are 135x80R15 the rolling radius will be 187.55mm = 6.151ft
At 1000 rpm
The Dyane 4th gear ratio is 1.315:1 = 760.456 rpm at the diff
Diff ratio is 4.125:1 = 184.353 rpm at the road wheel
184.353rpm x 6.151ft = 1,134 ft/min = 0.2147 miles/min = 12.882 MPH
Howard
here is a useful tyre comparison calculator
http://www.kouki.co.uk/utilities/visual ... calculator
Re: rpm per mph
Posted: Mon Nov 21, 2016 10:31 pm
by DMC
OK guys thanks for your input so ball park figure 13mph per 1000 rpm and i should be pretty close. Cheers. Dave.
Re: rpm per mph
Posted: Mon Nov 21, 2016 11:35 pm
by colonel_sponsz
There's a useful gear ratio calculator here:
http://dyane435.wixsite.com/cats-citroe ... lculations
It lets you play around with different A-series engine/ gearbox/ wheel combinations and does all the maths for you.
Re: rpm per mph
Posted: Thu Nov 24, 2016 1:42 pm
by yesnosorry
Hi
When People ask me How fast does it go?
My reply to non petrol heads is at 8,000 RPM it would be doing just over 100 Miles an Hour
Ha as if.
Lester
Re: rpm per mph
Posted: Sun Nov 27, 2016 9:33 am
by QFAD
Dave,
I calculated the following speeds (MPH) in each gear for QFAD fitted with 135 Michelins and std 2CV box with high ratio Crown & Pinion conversion (Rick Pembro conversion).
RPM 1st 2nd 3rd 4th
1000 3 7 10 13
2000 7 13 20 27
3000 10 20 30 40
4000 14 27 39 54
5000 17 33 49 67
5500 19 36 54 74
6000 20 40 59 80
6500 22 43 64 87
7000 24 46 69 94
Steve