Help me get my head around my tyres.

[Thom]

Ok so i need a new rear tyre, but not wanting to mix and match tyres im going to replace both of them.

My problem is i dont understand anything but the actual diametre of a tyre.

My bikes said to take tyres of 130/90 16 on the rear.

Could anybody tell me what determines these figures?

130 is width, yes?

So 90 must be height/profile, if i adjust the profile (to a lesser figure how will this affect my bike/riding?
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Current Bike: 1996 Yamaha TRX850 (The Japanese-Ducati One).
Previous Bikes: 1990 Honda NSR125 'Rothmans' (The smoking one), 1990 Suzuki GS500e 'Caf? fighter' (The loud one), 1987 Kawasaki GPX400r (The quick one), 1997 XJ600s Diversion (The reliable one), 2000 Kawasaki ER-5 (The spontaneously combustive one)

[Faraz]

130 - width
90 - profile
16 - diameter
____________________
'56 Yamaha MT-01
'05 Nissan 350z Roadster GT
3 words dude.. Fvck. Yes.

[owdamer]

[hmmmnz]

ill elaborate slightly

130 - width of tyre in mm
90 - profile, hight of tyre in a percentage of the width
16 - diameter, of the rim the tyre has to fit onto in inch's
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Thom]

so what your suggesting is:

"Thom, dinnit mess wif yer tyressssss may-te, it aint worf the risk!"

Cheers lad's.

And Hmmmmmnzzz it's nice to see you back
____________________
Current Bike: 1996 Yamaha TRX850 (The Japanese-Ducati One).
Previous Bikes: 1990 Honda NSR125 'Rothmans' (The smoking one), 1990 Suzuki GS500e 'Caf? fighter' (The loud one), 1987 Kawasaki GPX400r (The quick one), 1997 XJ600s Diversion (The reliable one), 2000 Kawasaki ER-5 (The spontaneously combustive one)

[hmmmnz]

i think its fine, often the tyres that came out on a bike or were recomended, were just that because the range of tyres at the time was so small,
you have plenty more choice these days,

basically tyre roll can be minimised by dropping a profile size,
doing that though means that you lose out on top speed as you have dropped 10% of the height,
circumference= 2xPi x r

often we try and make up the loss in height by increasing the tyre width, thus increasing the percentage of the height,
be aware that you can only really safely increase the width of you tyre 1 size

have fun
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Thom]

i actually want to reduce the profile, would this be advised if i kept the other measures the same?
____________________
Current Bike: 1996 Yamaha TRX850 (The Japanese-Ducati One).
Previous Bikes: 1990 Honda NSR125 'Rothmans' (The smoking one), 1990 Suzuki GS500e 'Caf? fighter' (The loud one), 1987 Kawasaki GPX400r (The quick one), 1997 XJ600s Diversion (The reliable one), 2000 Kawasaki ER-5 (The spontaneously combustive one)

[rotax81]

[hmmmnz]

yeah you could do it, but bear in mind you are lowering the height of the bike, ok not by much but it still might make a difference,

i personally would go for it, any thing to reduce tyre roll is a good thing in my eyes,


cheers for the welcome back,
its been a while, finally home in nz and connected to the net again
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Thom]

[iooi]

[hmmmnz]

i used to have a zxr750, i know all about harsh rides, its like a hard tail
i used to get bad tyre roll on the gs500 and that was only a 70 profile tyre
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches