speedo oddmeter inaccurate

Technical questions and answers about the Mazda Bongo

Moderators: Doone, westonwarrior

Post Reply
mentaliss
Bongolier
Posts: 348
Joined: Tue Apr 26, 2011 7:42 pm
Location: West Sussex

speedo oddmeter inaccurate

Post by mentaliss » Fri Sep 30, 2011 5:05 pm

against my sat nav speed reading my speedo is reading 7-10mph faster. (When we purchased the vehicle in June the vehicle supplier in Southampton changed the dial facia) to read mph. I've since complained this difference is too much they say that they can move the needle to get the correct reading??????? we have just returned from venice and the oddmeter indicates that we have done 979 kilometers or mileage, not sure any longer which! in both cases this is also wrong...can anyone advise if this is a problem that can be fixed?
skater
Bongolier
Posts: 274
Joined: Sun Apr 22, 2007 8:59 pm
Location: Devon

Re: speedo oddmeter inaccurate

Post by skater » Fri Sep 30, 2011 5:59 pm

One thing to consider/check:

When my rear tyres were standard size ie 215/65/15 my speedo read 60mph
but the satnav said 56mph.

I now have 225/70/15 on the back and the speedo and satnav read the same ( +- half mph ish ).

What size are your tyres?

In terms of your Venice trip, how many miles by satnav? If you know that you could convert to Kms
then see which is closer to the bongo odo reading of 979.

Someone will probably be along with a good way to work it out- links to tyre size conversion calculators etc.

James
" it's not rocket surgery! "
David Edwards
Supreme Being
Posts: 4100
Joined: Sat Oct 16, 2004 6:37 pm
Location: Aberdare south wales

Re: speedo oddmeter inaccurate

Post by David Edwards » Fri Sep 30, 2011 7:25 pm

yep prob find it's the tyres, same as mine, I actually prefer it like it is, helps with the dreaded speed cameras,lol.
teenmal
Supreme Being
Posts: 3656
Joined: Thu Mar 27, 2008 6:08 pm
Location: north lanarkshire

Re: speedo oddmeter inaccurate

Post by teenmal » Fri Sep 30, 2011 7:31 pm

mentaliss wrote:against my sat nav speed reading my speedo is reading 7-10mph faster. (When we purchased the vehicle in June the vehicle supplier in Southampton changed the dial facia) to read mph. I've since complained this difference is too much they say that they can move the needle to get the correct reading??????? we have just returned from venice and the oddmeter indicates that we have done 979 kilometers or mileage, not sure any longer which! in both cases this is also wrong...can anyone advise if this is a problem that can be fixed?

Hi
Your vehicle supplier should be able to zero the needle for you,the the speedo will be clocking up in KMs,you can check it with your sat nav.Or travel at 60 mph for one minute =1mile not 1.6 if 1.6 its KMs..

Cheers..
mentaliss
Bongolier
Posts: 348
Joined: Tue Apr 26, 2011 7:42 pm
Location: West Sussex

Re: speedo oddmeter inaccurate

Post by mentaliss » Fri Sep 30, 2011 7:44 pm

skater wrote:One thing to consider/check:

When my rear tyres were standard size ie 215/65/15 my speedo read 60mph
but the satnav said 56mph.

I now have 225/70/15 on the back and the speedo and satnav read the same ( +- half mph ish ).

What size are your tyres?

In terms of your Venice trip, how many miles by satnav? If you know that you could convert to Kms
then see which is closer to the bongo odo reading of 979.

Someone will probably be along with a good way to work it out- links to tyre size conversion calculators etc.

James
Yes, I understand where your comming from, your talking about the rolling circumference of the tyre from one point to another I havent checked this yet, im running 220/55/17 rears, Im more interested if its true that I can move the speedo needle.
teenmal
Supreme Being
Posts: 3656
Joined: Thu Mar 27, 2008 6:08 pm
Location: north lanarkshire

Re: speedo oddmeter inaccurate

Post by teenmal » Fri Sep 30, 2011 7:52 pm

mentaliss wrote:
skater wrote:One thing to consider/check:

When my rear tyres were standard size ie 215/65/15 my speedo read 60mph
but the satnav said 56mph.

I now have 225/70/15 on the back and the speedo and satnav read the same ( +- half mph ish ).

What size are your tyres?

In terms of your Venice trip, how many miles by satnav? If you know that you could convert to Kms
then see which is closer to the bongo odo reading of 979.

Someone will probably be along with a good way to work it out- links to tyre size conversion calculators etc.

James
Yes, I understand where your comming from, your talking about the rolling circumference of the tyre from one point to another I havent checked this yet, im running 220/55/17 rears, Im more interested if its true that I can move the speedo needle.


Hi the needle can be moved,I would let your supplier do it for you as they suggested.
User avatar
briwy
Supreme Being
Posts: 1754
Joined: Thu Jul 22, 2010 11:12 pm
Location: Peak District

Re: speedo oddmeter inaccurate

Post by briwy » Fri Sep 30, 2011 8:20 pm

Even if you sort out the needle you have obviously got a problem as you say with the odometer, unless Venice has been moved.

One way round it is to fit a speedo from a Mazda petrol car. cant remember which one, may be an old Mazda 3. These have a reference GA5 on the dial and both the speedo and odometer read in miles.

If you ask around someone may have one.
User avatar
dave_aber
Supreme Being
Posts: 2884
Joined: Tue May 12, 2009 4:33 pm
Location: Elgin, Scotland

Re: speedo oddmeter inaccurate

Post by dave_aber » Fri Sep 30, 2011 10:30 pm

The one you need is a GA5R speedo from a Mazda 626 of around 1991 age. Direct replacement, and will read distance & speed accurately on the correct size wheels
Image...Image
There are 10 types of people in this world.
Those that understand binary, and those that don't.
mentaliss
Bongolier
Posts: 348
Joined: Tue Apr 26, 2011 7:42 pm
Location: West Sussex

Re: speedo oddmeter inaccurate

Post by mentaliss » Sat Oct 01, 2011 2:26 pm

dave_aber wrote:The one you need is a GA5R speedo from a Mazda 626 of around 1991 age. Direct replacement, and will read distance & speed accurately on the correct size wheels


thanks pepole for you help.
User avatar
maxheadroom
Supreme Being
Posts: 1950
Joined: Wed Feb 28, 2007 6:37 pm
Location: Gloucester

Re: speedo oddmeter inaccurate

Post by maxheadroom » Sun Oct 02, 2011 10:43 am

Keep the Faith

Image
teenmal
Supreme Being
Posts: 3656
Joined: Thu Mar 27, 2008 6:08 pm
Location: north lanarkshire

Re: speedo oddmeter inaccurate

Post by teenmal » Sun Oct 02, 2011 11:14 am

This place is always worth a look for s/h bits.



http://www.u-pull-it.co.uk/info.html?vi ... tPricelist

Cheers.
Post Reply

Return to “Techie Stuff”