Calibrating the speedo
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From: Cheshire, England
Calibrating the speedo
Thought it worth a new thread for this, even though it's also tagged on the end of the thread about the odometer problem.
I should have done this years ago! I've put up with an adrift speedo reading for years and years, then found a company that would recalibrate it for about £65. Then I thought 'Oh for heaven's sake - how hard can it be?!'
Pretty easy to do - I gave the needle a 'guess twist' on the work table, but then put the speedo back in the car without its glass to tweak it against a GPS while out and about.
I now have a 2mph error at 20mph, 1 at 30, then it is spot on at 40, 50, 60, 70, 80 and 90. Very pleased.
A little tricky taking off and refitting the glass - one of those jobs that would be much easier if you'd done it before. There are little slots at the very top and bottom of the gauge, just under the crimped lip. If you can coax a small screwdriver blade into that to get you started, then you can just slip the blade around one half of the circumference, giving it a little wriggle as you go. Similar idea for getting it back together. Note: it is far easier to avoid touching the inside of the glass than it is to wipe any marks off afterwards - I recommend blowing it to remove any dust rather than wiping.
My speedo had a 5-6mph error, and the needle sat at rest on the first marking. Here's how it looks now.
I should have done this years ago! I've put up with an adrift speedo reading for years and years, then found a company that would recalibrate it for about £65. Then I thought 'Oh for heaven's sake - how hard can it be?!'
Pretty easy to do - I gave the needle a 'guess twist' on the work table, but then put the speedo back in the car without its glass to tweak it against a GPS while out and about.
I now have a 2mph error at 20mph, 1 at 30, then it is spot on at 40, 50, 60, 70, 80 and 90. Very pleased.
A little tricky taking off and refitting the glass - one of those jobs that would be much easier if you'd done it before. There are little slots at the very top and bottom of the gauge, just under the crimped lip. If you can coax a small screwdriver blade into that to get you started, then you can just slip the blade around one half of the circumference, giving it a little wriggle as you go. Similar idea for getting it back together. Note: it is far easier to avoid touching the inside of the glass than it is to wipe any marks off afterwards - I recommend blowing it to remove any dust rather than wiping.
My speedo had a 5-6mph error, and the needle sat at rest on the first marking. Here's how it looks now.
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From: Australia
Thought it worth a new thread for this, even though it's also tagged on the end of the thread about the odometer problem.
I should have done this years ago! I've put up with an adrift speedo reading for years and years, then found a company that would recalibrate it for about £65. Then I thought 'Oh for heaven's sake - how hard can it be?!'
Pretty easy to do - I gave the needle a 'guess twist' on the work table, but then put the speedo back in the car without its glass to tweak it against a GPS while out and about.
I now have a 2mph error at 20mph, 1 at 30, then it is spot on at 40, 50, 60, 70, 80 and 90. Very pleased.
A little tricky taking off and refitting the glass - one of those jobs that would be much easier if you'd done it before. There are little slots at the very top and bottom of the gauge, just under the crimped lip. If you can coax a small screwdriver blade into that to get you started, then you can just slip the blade around one half of the circumference, giving it a little wriggle as you go. Similar idea for getting it back together. Note: it is far easier to avoid touching the inside of the glass than it is to wipe any marks off afterwards - I recommend blowing it to remove any dust rather than wiping.
My speedo had a 5-6mph error, and the needle sat at rest on the first marking. Here's how it looks now.
I should have done this years ago! I've put up with an adrift speedo reading for years and years, then found a company that would recalibrate it for about £65. Then I thought 'Oh for heaven's sake - how hard can it be?!'
Pretty easy to do - I gave the needle a 'guess twist' on the work table, but then put the speedo back in the car without its glass to tweak it against a GPS while out and about.
I now have a 2mph error at 20mph, 1 at 30, then it is spot on at 40, 50, 60, 70, 80 and 90. Very pleased.
A little tricky taking off and refitting the glass - one of those jobs that would be much easier if you'd done it before. There are little slots at the very top and bottom of the gauge, just under the crimped lip. If you can coax a small screwdriver blade into that to get you started, then you can just slip the blade around one half of the circumference, giving it a little wriggle as you go. Similar idea for getting it back together. Note: it is far easier to avoid touching the inside of the glass than it is to wipe any marks off afterwards - I recommend blowing it to remove any dust rather than wiping.
My speedo had a 5-6mph error, and the needle sat at rest on the first marking. Here's how it looks now.
