Speado healers & sprocket sizes...Help please

[Ward P]

Can you run a healer on a car?? My new car is over 10% out. Totally shits me as the old car was spot on. I complained bitterly and dealer replaced the speedo cluster but made no difference. They reckon the sender is spot on, and the odometer seems to read correct, just the speedo reading high. $70k and a shit speedo. Shit Aussie built Toyotas.

I run a 43 back on the bike these days, the speedo on it is about 15% out. But as I know I don't care.