Speedo errors, what to do if it's WAY out?

yambabe · World Chat Champion Joined: 12 Jul 2004 Karma :

Sigh.

Nothing is ever straightforward is it?

Finally got a working speedo on today (after taking the front wheel off and finding out my bearings were FUBAR as well - ever tried to fine new ones on a Saturday afternoon? Rolling Eyes

Managed to find one, the other wasn't quite as bad so hopefully will last to Monday) only to find out that the speeds it shows are way, way out.

The clocks are KPH, and had stickers about where you'd expect to find them, 30mph was at 50kph, 50mph at around 80 kph and 70mph at about 110kph. So we did a bit of side-by-side riding to check how accurate they are against the VT (which is reasonably accurate as far as we know.)

At 30mph on the Honda, my bike was showing 40kph, which according to the conversion websites should only be about 25mph.

At 80mph on the Honda, my speedo was only just on 100kph, which should be about 60! Shocked

We've put some 30, 40 and 70 stickers on the clocks ourselves (so I stand a chance of keeping my licence lol) but I was wondering is there any way of re-calibrating the speedo drive or the clocks so that it is more accurate?
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G · The Voice of Reason Joined: 02 Feb 2002 Karma :

Presuming it's driven from the front wheel, there's no really good way to do it as far as I know.

Best bet might be to see if you can take the clocks apart, then print off a custom made insert for the 'dial'.
Best to get a GPS to check the speedo if you can, so you know it's correct.

Often bike speedos are easily 10% out and can be further put out by different tyres etc.

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Err, not the wrong speedo drive is it?

Cannot think of an easy way to recalibrate it on a cable one. No doubt there are specialists who can do it but suspect they are not cheap.

All the best

Keith
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yambabe · World Chat Champion Joined: 12 Jul 2004 Karma :

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

Could well be then. Whats the betting your bike is loosly based on another non custom model with a very different front wheel size.

All the best

Keith
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Jack_Cheese · World Chat Champion Joined: 14 Jul 2005 Karma :

I'm with G, just print a new insert, the clocks must come apart somehow.

Jack
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Jebus · Brolly Dolly Joined: 10 Jul 2004 Karma :

you can get the speedo sorted to read as well as the fancy ones coppers use to nab you for speeding, you send it off and they sort it out, no idea on costs tho
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colin1 · Captain Safety Joined: 17 Feb 2005 Karma :

yeah as others have suggested, do a new insert
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Itchy · Super Spammer Joined: 07 Apr 2005 Karma :

yambabe · World Chat Champion Joined: 12 Jul 2004 Karma :

Oooh, have you been recently Itchy? Has he still got that 600 Shadow in? Quite fancied that one...... Very Happy

We mostly use MDL here in Warrington, we know Mick pretty well and he knows our bikes so he knows what will or won't fit, what will fit with a bit of a bodge if we're desperate etc etc.
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