sip speedo gear ratio setting??? getting speedo right

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smoore-gt225
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hi i am trying to set up my sip speedo but gps saying 65 speedo saying 55
i have set the gear ratio at 0.77 but after reading the book it says thats for li series 3
my scoot is a series 2 li125 gear box on 16/46 sprockets, the speedo drive is a scootrs ext disc brake also does having a schwalbe 100/90/10 interfere with the gear ratio setting
anybody help with the speedo setting i need to get it right
cheers steve
rosscla
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0.77 is the gear ratio on the standard speedo drive gear, I'd guess that the ScootRS drive will be the same. The book also gives you the formula to work the ratio out from the number of teeth on the drive cogs.

The gearbox type has nothing to do with setting the speedo settings

The bigger tyre might make a difference, did you measure and set the circumference for this tyre?
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smoore-gt225
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hi meant to say bigger tyre on rear normal 3.50/10 on the front so set it to the front
cheers steve
Minority
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You could always just increase the tyre circumference parameter until you get it spot on (presumably you have it set at about 1357 for a 3.50/10).
That's what I did to fine tune mine to the GPS.
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smoore-gt225
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Minority wrote:You could always just increase the tyre circumference parameter until you get it spot on (presumably you have it set at about 1357 for a 3.50/10).
That's what I did to fine tune mine to the GPS.
i was thinking that, how much did you go up on measurement
cheers steve
Minority
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smoore-gt225 wrote:
Minority wrote:You could always just increase the tyre circumference parameter until you get it spot on (presumably you have it set at about 1357 for a 3.50/10).
That's what I did to fine tune mine to the GPS.
i was thinking that, how much did you go up on measurement
cheers steve
I'm using the electronic sensor not the speedo cable so I'm afraid my setting won't be of any use to you.
However looking at your figures (65 gps 55 speedo) you would have to increase the circumference by multiplying by 1.18 (eg 1357 x 1.18 = 1601)
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soulsurfer
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Could anyone explain or recommend how to set up the speedo using the sensor instead of cable with a wheel circumference of 1400mm?
I'm asking for a mate as his speedo goes up and down like a yoyo and he doesn't have any instructions.

I realise this may be explained elsewhere, but there really are many pages to wade through and it doesn't help with Eden's posts being deleted, so any direct help on this matter would be appreciated ;)

Many thanks
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sideout
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soulsurfer wrote:.... I'm asking for a mate as his speedo goes up and down like a yoyo and he doesn't have any instructions......
Not a lumpy Schwalbe tyre is it? :)
.....I'll get me coat :arrow:

Wheel circumferences vary quite a bit, don't they? I use 1287 for Bridgestone Hoops with a Ratio of 0.78.
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soulsurfer
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It's a Series 5 Nigel ;-)
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rosscla
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Is anyone using the magnetic sensor with an original disk hub, if so where are you mounting the magnet/sensor?
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