Tyre size/Speedo reading

[Ry_B]

According to loads of tyre calculators on the internet, my new tyres should make my speedo read about by 2.6%...

With the original tyres on the limiter was at 30 in 1st and 50 in 2nd. With my new tyres on the limiter is still exactly the same so does this mean the tyres haven't effected the speedo? :thumbup:

[saxoash]

ok then cheers

[Ry_B]

ok then cheers

:err: what's that meant to mean, I'm asking a perfectly sensible question...

[Yates]

ash is a prick, he comes out with random shit trying to be funny, hes not tho

it seems that way, altho i dont have a clue about it

[kcsaxo]

if you got tyres that are bigger than the original sizes when put side to side, then the speedo will be affected. thing is when you hit the limiter and it still reads 30 for example, the actual reading is going to be that 2.6% difference which the speedo wont pick up. so in other words you will be going fast than what it says.

[Danadaman_3]

It wont be out by a noticable amount. at 30 you will be 1 - 2 mph out. at 60 / 70 you will be 3 - 4 i would imagine but your not going to get pulled for doing a few mph over TBH

plus your allowed the speed limit plus 10% + 1mph thats official.

so in a 30 ur allowed 34 tops and 67 in a 60 so on . . .

[Yates]

its not 10% plus one is it? my mate got done doing 34, which would be 10% plus 1 if your right, i always thought it was just 10%

[kcsaxo]

i dont even do the 10% thing, just stick to the limit and be safe.

[westy4a69]

youre right i think it is just 10%... but like kc says i just stick to the speed limit dont want to get too cocky!

[Mark]

According to loads of tyre calculators on the internet, my new tyres should make my speedo read about by 2.6%...

With the original tyres on the limiter was at 30 in 1st and 50 in 2nd. With my new tyres on the limiter is still exactly the same so does this mean the tyres haven't effected the speedo? :thumbup:

Correct! The speedometer effectively measures how many times your wheels go around, not how fast you are travelling.

Without changing your gear ratios, you speedometer will always indicate 30 in 1st gear at the limiter. Even if you had no wheels attached and were going nowhere.

The 2.6% is referring to the difference between your indicated speed and your actual (theoretical) speed.

e.g. If you fitted really small wheels, your speedometer would indicate 30, but you'd probably only be travelling at 10. Likewise if you fitted huge tractor wheels your speedometer would still indicate 30 but you'd be travelling at over 100. (this is theory - I wouldn't try it).

[Ry_B]

Ok cheers lol, I think I'm getting a Road Angel for my 18th next week so should all be good anyway :)

[addictedtosax]

It wont be out by a noticable amount. at 30 you will be 1 - 2 mph out. at 60 / 70 you will be 3 - 4 i would imagine but your not going to get pulled for doing a few mph over TBH

plus your allowed the speed limit plus 10% + 1mph thats official.

so in a 30 ur allowed 34 tops and 67 in a 60 so on . . .

and of course speedos are 10% out anyway, so you could have your speedo reading nearer 37mph in a 30 zone and not get into bother;)

[JackoSaxAppeal]

Deleted account!

[MrBirdPoo]

All this talk fo speedos being so inaccurate. I bought a Snooper Evolution Neo and when my speedo says I'm doing 70, it says I'm doing 70. However its at 30mph on the Snooper that the speedo is out cause it says 32mph