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Author Topic: Recalibrating OEM speedo  (Read 2044 times)

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Offline MRieck

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Recalibrating OEM speedo
« on: July 22, 2005, 02:30:03 PM »
Does anyone know of someone who recalibrates speedos  OR knows of a speedo drive that will allow an 18" front wheel to work accurately with the OEM (19") CB speedo?
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Offline Mark M

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Re: Recalibrating OEM speedo
« Reply #1 on: July 22, 2005, 03:02:30 PM »
It is nice to forget your speedo is overeading sometimes, then again it's also nice to know how fast you realy are going.

Anyone?

BTW I've seen your 'million dollar' tag, but still have no idea what it's all about, whats the story?
   
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Offline MRieck

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Re: Recalibrating OEM speedo
« Reply #2 on: July 22, 2005, 03:57:23 PM »
Mark  The "Million Dollar CB" was a tag given to the bike years ago by a parts guy I ordered many parts through. He is actually the Parts Manager of the shop I buy all OEM pieces through( that includes Honda, Suzuki, Yamaha, Kawasaki and the occasional BMW piece) and I've known him about 15 years come to think of it. The reason for the tag is the fact that the bike has had no expense spared to make it what it is today. It has many "one off"/aftermarket pieces and many, many hours of work to make it what it is today. It works better than new and hauls ass. It puts the fear of God in 600cc bikes even with my fat ass on it! New bikes have "speedohealers" etc to compensate for gearing changes as they work off electronic impulses. I have one of those units on my Hayabusa and it works great. I very particular about things being "right" so if anyone can help.......
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Offline Robert

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Re: Recalibrating OEM speedo
« Reply #3 on: July 22, 2005, 04:23:15 PM »
It really is a dream machnine.
Not that I can be of much help, but is that OEM speedo purely mechanically driven (internally) or "magnetic" (eddy current)?
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Offline MikeDeB

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Re: Recalibrating OEM speedo
« Reply #4 on: July 23, 2005, 01:36:08 AM »
Quote from: Robert on July 22, 2005, 04:23:15 PM
It really is a dream machnine.
Not that I can be of much help, but is that OEM speedo purely mechanically driven (internally) or "magnetic" (eddy current)?

They are a magnetic drive inside what looks like a gearbox attached to the rear of the speedo/tach.  The odometer/trip odometer are mechanically driven off a worm gear in the bottom of the gearbox, below the rotating magnet.  The calibration is going to have to come in the form of a change in gearing at the front wheel speedo drive.  Hope this helps.
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Offline MRieck

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Re: Recalibrating OEM speedo
« Reply #5 on: July 23, 2005, 10:41:24 AM »
Will a 400F speedo drive fit? Those came with 18" fronts if I remember correctly. Is the speedo ratio different internally on the 400F speedo? Anyone?
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Offline clarkjh

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Re: Recalibrating OEM speedo
« Reply #6 on: July 23, 2005, 12:57:01 PM »
How is the smaller wheel going to effect handleing?

I have two nice solid 18" rims and all the fixens from a GS400 that I was thinking of putting on to replace my rusted spokes and wheels

James
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Offline Mark M

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Re: Recalibrating OEM speedo
« Reply #7 on: July 24, 2005, 01:57:11 AM »
Theory suggests that handling is a little lighter, having also changed the bars and almost everything else on the bike, it is. Also there is a bigger choise of more modern rubber. Very Slight loss of ground clearance, but pegs are raised and back so it will be the alternator down first now. 
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Offline frostypuck

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Re: Recalibrating OEM speedo
« Reply #8 on: July 24, 2005, 04:52:45 AM »
Mike,
There's a place off the Mass.Pike in Allston that calibrates and certifies speedos. I'll try and find the name/address and you can call them and see if they'll do somethig with a bike speedo.
Chris
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