[Author Index]
[Date Index]
[Thread Index]
[Date Prev][Date Next][Thread Prev][Thread Next]
[ST] RE: effect on tach?
- Subject: [ST] RE: effect on tach?
- From: "Keith Tynan" <keith@xxxxxxxxxxxxxxx>
- Date: Tue, 14 May 2002 08:37:31 +0100
> Date: Mon, 13 May 2002 22:16:53 -0400
> From: "rmasiak" <rmasiak@xxxxxxxxxxx>
> Subject: Re: [ST] effect on tach?
> ...
> I was going to wait till I was ready but since this topic was brought up I
> have a question for everyone. With stock ratio of 19/43 I run 5000 RPM
> doing 86 MPH. I want to change my front sprocket at my 12000 mi
> service but
> unsure if I want 18/43 or 17/43.
>
> Question: Anyone out there who is running 18/43 or 17/43, what
> is your RPM in 6th gear doing 86 MPH???
>
> I know the RPM will go higher with each step but how much will make my
> decision on which setup I want. Any input would be appreciated.
Rich,
Most of your answer can be found in the chart on
http://www.triumphnet.com/st/faq/chain/index.html
As the theoretical top speeds in this table represents 9600 rpm, the speed
for 5000 rpm can be found by multiplying the top speed by 0.521, i.e.
ratio mph @5000
19/43 86.5
19/45 82.3
18/43 81.8
18/45 78.1
17/43 77.6
17/45 74.0
Or, to put it another way:
ratio rpm @86 mph
19/43 4973
19/45 5225
18/43 5259
18/45 5504
17/43 5541
17/45 5814
Fraid I don't have access to the specific fuel consumption graphs...
Of course, all of this depends on what tyres you wear, as the circumference
changes a bit from brand to brand.
FWIW, I currently run 18/45 and my bike indicates 80 mph @ 5000 rpm (near as
damnit).
Regards,
- --
BRG
mailto:keith.tynan@xxxxxxxxxxxxx
http://myweb.tiscali.co.uk/keith.tynan
'00 BRG Sprint ST 'Wolfram'
* * * * * * * * * * * * * * * * * * *
The ST/RS Mailing list is sponsored by Jack Lilley Ltd.
http://www.TriumphNet.com/st/lilley for more info
http://www.TriumphNet.com/st for ST, RS and Mailing List info
=-=-=-= Next Message =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=