Leading on from my last topic on SC/helical (and to avoid going too off topic in that one), thought I'd start a new thread on gear ratios.
I've got the gearcalc Pc program which lets me plug in any ratios I like, gives speed at given rpm, rpm drops between gears and a nice little graph.
Ignoring desired speed and rear end ratio for now, what sort of difference between each gear is reasonable? I'll be using a 4-speed box, with 1:1 top ratio.
Looking at bar chart of gear ratios, is it better to have a straight diagonal line through them or more of a decreasing gradient curve? I suppose the other way to look at it is should gear ratios get closer from 1st to 4th or try and keep gaps more or less the same (which would seem to make gearchanges easier if rpm drop is the same each time?)
I might be answering my own question here ,but I think in an ideal world you would have an even drop, but in reality to keep a reasonable first gear ratio and still a good top end speed (without going to wide on ratios) you would need uneven drops and a taller (by this I mean lower speed but may have got wrong term) first gear for good "off the lines"
Is there a rough and ready approximate value that is considered a reasonable rpm drop between gears?
Just re-read this and it doesn't seem very clear, hopefully some of you clever bods on here can make sense of it...
Cheers
Jono
I've got the gearcalc Pc program which lets me plug in any ratios I like, gives speed at given rpm, rpm drops between gears and a nice little graph.
Ignoring desired speed and rear end ratio for now, what sort of difference between each gear is reasonable? I'll be using a 4-speed box, with 1:1 top ratio.
Looking at bar chart of gear ratios, is it better to have a straight diagonal line through them or more of a decreasing gradient curve? I suppose the other way to look at it is should gear ratios get closer from 1st to 4th or try and keep gaps more or less the same (which would seem to make gearchanges easier if rpm drop is the same each time?)
I might be answering my own question here ,but I think in an ideal world you would have an even drop, but in reality to keep a reasonable first gear ratio and still a good top end speed (without going to wide on ratios) you would need uneven drops and a taller (by this I mean lower speed but may have got wrong term) first gear for good "off the lines"
Is there a rough and ready approximate value that is considered a reasonable rpm drop between gears?
Just re-read this and it doesn't seem very clear, hopefully some of you clever bods on here can make sense of it...
Cheers
Jono