7 replies to this topic

[runkthepunk]

Hello

My engine is a 1.3 1989 metro unit and my car is a 1991 cooper running a standard set of dials

My speedo gives an incorrect reading but there doesn't seem to be a logical calculation to it i.e alway 10 MPH under/over

It seems to be correct up to about 10 MPH then gets steadily more off and will not go any higher than 45/50 MPH and I know I was doing 70 at one point on the motorway (sat nav)

Any ideas what could be causing this because its pretty annoying and I don't have a cigarette lighter adapter so my sat nav eventually runs out of battery

Rob

[Guess-Works.com]

The speedo drives in the side of the gearbox are calibrated for a Metro with bigger wheels and a different speedometer, you need to change these to the correct ratios for a mini speedo...

use this to help...

http://www.guess-wor...nical/ratio.htm

you will need the tyre size, the final drive ratio in the gearbox and the tpm of your speedometer...

[runkthepunk]

The speedo drives in the side of the gearbox are calibrated for a Metro with bigger wheels and a different speedometer, you need to change these to the correct ratios for a mini speedo...

use this to help...

http://www.guess-wor...nical/ratio.htm

you will need the tyre size, the final drive ratio in the gearbox and the tpm of your speedometer...

Thanks for that really useful information I will have to get it set up properly before going on any long runs

Cheers

Rob

[matt615]

My speedo gives an incorrect reading but there doesn't seem to be a logical calculation to it i.e alway 10 MPH under/over

It seems to be correct up to about 10 MPH then gets steadily more

That sounds logical to me! It will be a percentage error rather than a fixed figure. For example if it's reading 20% over then at 5mph it would read 6mph - hardly noticable. However at 50mph it would be showing 60mph.

As said above, you need to change the speedo drive gears. This is a common problem when fitting Metro engines to Minis.

[runkthepunk]

My speedo gives an incorrect reading but there doesn't seem to be a logical calculation to it i.e alway 10 MPH under/over

It seems to be correct up to about 10 MPH then gets steadily more

That sounds logical to me! It will be a percentage error rather than a fixed figure. For example if it's reading 20% over then at 5mph it would read 6mph - hardly noticable. However at 50mph it would be showing 60mph.

As said above, you need to change the speedo drive gears. This is a common problem when fitting Metro engines to Minis.

Ah I see, I was expecting just a fixed figure difference as on my old mini the speedo itself was faulty and always read 10mph over speed

Is the task of changing the relevant parts difficult or not?

Thanks

Rob

[matt615]

Is the task of changing the relevant parts difficult or not?

If the engine is out of the car, they are very easy to change. With the engine in the car it's a bit more fiddly! You'll need to remove the radiator and the radiator side engine mounting. Then you need to jack that side of the engine up slightly to get access to the parts you need to remove.

[ZED]

i have the same problem, the easiest way is to follow someone and just make a mental noted where 30/40/50 etc
but recently i actually logged the mile for a journey i do regular, 45 miles to work. my mini showed 30 miles. which is 30% less, so my speed should be 30% more then the reading.

so when my speedp shows 20, i am doing 26,
50, i am doing 65

[runkthepunk]

Seasons Greetings!

Is this job (speedo drive change) something a local garage can do or is it I will have to attempt myself? I am not really good enough to attempt stuff like this without causing more problems so really need another option

Although another possibility I have heard about are Speedo Ratio Convertors basically inline units that change the speedo cable turns down to the correct amount. Does anyone else know about these and if I can get one for the metro engine to mini dials?

Thanks

Rob