QUESTION
I need your advice regardingn my speedo - it under-reads by about 10%, any ideas why this would be?
I did get a new cable made last year and had the speedo itself overhauled, could it be the speedo or the drive in the gearbox, what do you think?
T.M - Sydney NSW
ANSWER
If you have recently calibrated the speedo instrument and changed the cable then this leaves three likely suspects
1) Changing wheels and tyres where the rolling radius is not per the original tyres specs will influence your speedo reading
2) Changing the differential ratio also affects the speedo reading
3) Changing gearboxes and not fitting the correct colour coded (black, green etc.) speedo driven gear will affect instrument readings
Copyright © 2022 Lotus Marques
I need your advice regardingn my speedo - it under-reads by about 10%, any ideas why this would be?
I did get a new cable made last year and had the speedo itself overhauled, could it be the speedo or the drive in the gearbox, what do you think?
T.M - Sydney NSW
ANSWER
If you have recently calibrated the speedo instrument and changed the cable then this leaves three likely suspects
1) Changing wheels and tyres where the rolling radius is not per the original tyres specs will influence your speedo reading
2) Changing the differential ratio also affects the speedo reading
3) Changing gearboxes and not fitting the correct colour coded (black, green etc.) speedo driven gear will affect instrument readings
Copyright © 2022 Lotus Marques
