Michelin Road 5

[Irish in Oz]

And I totally agree with you Hooli about tipping in, but put on the different tyre speedo will change and it will as it wears, so put stickers on the clock to give true reading without thinking about it all the time.

[Kiwifruit]

Irish there are sites that will calculate the difference in speedo reading with different size tyres......just got to find one

[Irish in Oz]

As I said on post above Col "who cares" if it worries you use a GPS.

[Hooli]

I do it manually.

As far as I know this is correct -

A 190/50ZR17 tyre is
190mm wide
190*0.5 high, so 95mm
on a 17" Rim or 431.8mm in french

Total height = 431.8+(2x95)=621.8
621*Pi = 1953.44mm diameter

A 180/55ZR17 tyre is
180mm wide
180*0.55 high, so 99mm
on a 17" Rim or 431.8mm in french

Total height = 431.8+(2x99)=629.8
621*Pi = 1978.58mm diameter

Difference -
1978.58 - 1953.44 = 25.14mm
(25.14 / 1978.58 = 0.0128) * 100 = 1.28%

So a 180/55 tyre is 1.28% larger & will give a speedo reading that much lower.

(I must have been thinking of a 180/50 earlier when I said it was smaller).

Simple eh?

[Hooli]

As for who cares, it's much cheaper to work it out without buying the new tyres & going for a ride to check the GPS.

[Irish in Oz]

NOW THIS IS GETTING FECKIN STUPID.

[Irish in Oz]

Hooli you are buying new tyres regardless of brand, so are you saying a Michelin and a Pirelli or any other brand will be exactly the same perimeter because they say the same numbers on the side wall.

[Kiwifruit]

So it seems the difference between a 55 and a 50 at 100kph is a 55 will make the speedo read about 3kph lower.
My 107kph camera ticket would now be for 110kph.
So thats it end of story .....life is easy.   

[Hooli]

Hooli you are buying new tyres regardless of brand, so are you saying a Michelin and a Pirelli or any other brand will be exactly the same perimeter because they say the same numbers on the side wall.

No I think they differ a bit, but I've never seen an online calculator that takes account of the make/model of the tyre either.

[GSXKING]

I had these fitted to my bike two months ago. The grip level is great now . I had to drop my pressures from Metzler Z7's. 180/55 rear 120/70 front. Lifter kit under rear shocks. Turn in is really positive. I really want to test them in the wet if it ever rains again 

[Milts]

Irish there are sites that will calculate the difference in speedo reading with different size tyres......just got to find one

  Maybe of some help

https://www.tacomaworld.com/tirecalc

[Kiwifruit]

Thanks Milts. Thats the one l found but unlike yourself am not skilled enough to do the cut n paste thingy   

[Milts]

@Kiwifruit

                      Believe me i struggle with all this techy stuff myself.

I will try and explain how to attach a link.

Move the cursor into the search window at the top of the page,  for example   gsx1400owners.org/forum....... 

left click - that will highlight the wording in blue
then right click - a drop down box will appear
then left click the word 'copy'


Now to insert the link into the message you are preparing, move the cursor to where you want attach link

left click, then right click - a drop down will appear left click the word 'paste'.

Hey presto your link should appear.


I'm sure someone can come along with a better 'how to' but hope that helps   

[Kiwifruit]

Sounds easy Milts   

[Kiwifruit]

Talking to the mechanic that fitted my tyres and it appears l have been running  the 5's too low.
Seems Michelin recommend 36F, 42R
l had been running 36/38 with a tyre gauge read 2 psi low.
And l wonder why they had squared up 
Nice be back on a bike with new boots.