Bimota Forum

stox · Joined: 08 Dec 2015 Posts: 31 Location: Bedfordshire

I see the sb6 is listed as using a 180/55 profile tyre and the sb6r a 190/55. I thought they had the same wheels?

Looking to get some new ones for my 6r and wondered what profile works best for fast road riding?

Jonny B Bad · Joined: 05 Dec 2009 Posts: 555 Location: NE London

I have had a 190 on my 6r and it was fouling the chain. So I went back to a 180, which tyre fitters say is the maximum you should be putting on a 5.5 inch wheel anyway. 180 is definitely the way to go.
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What, Jonny's gone!

Jonny B Bad · Joined: 05 Dec 2009 Posts: 555 Location: NE London

I have had a 190 on my 6r and it was fouling the chain. So I went back to a 180, which tyre fitters say is the maximum you should be putting on a 5.5 inch wheel anyway. 180 is definitely the way to go.
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What, Jonny's gone!

stox · Joined: 08 Dec 2015 Posts: 31 Location: Bedfordshire

Thank you (twice) Very Happy

brian · Joined: 22 Aug 2011 Posts: 3769 Location: Australia

180/55
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'99 DB4 #104, '96 SB6 #1165, '94 DB2 J #652, '99 DB4 #088, '08 VTX1800, '93 ZXR750R M1, '95 ZXR750, '95 ZXR750 Race Bike, '94 CBR400rr NC29 Race Bike, '94 CB250, '49 BSA C10 250, '61 BSA A10 650, '89 ZXR750, '91 Ducati 851

brian · Joined: 22 Aug 2011 Posts: 3769 Location: Australia

Also interesting that the sb6 has a 120/60 front which is not all that common on sports bikes. Usually see 120/70
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'99 DB4 #104, '96 SB6 #1165, '94 DB2 J #652, '99 DB4 #088, '08 VTX1800, '93 ZXR750R M1, '95 ZXR750, '95 ZXR750 Race Bike, '94 CBR400rr NC29 Race Bike, '94 CB250, '49 BSA C10 250, '61 BSA A10 650, '89 ZXR750, '91 Ducati 851

vort28 · Joined: 22 Mar 2010 Posts: 2194 Location: Northwest , UK

Replaced my 60 series front many years ago with a 120/70 . Seem to remember it was a handling mod and the SB7 runs a 120/70 as standard , but could be wrong.

Evilchicken0 · Joined: 12 May 2010 Posts: 2996 Location: London

I put a 120 / 70 on mine, it can make the mudguard a bit tight
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sb8rs · Joined: 05 Aug 2011 Posts: 150 Location: London

As far as I am aware, Bimota gave different tyre sizes for different type of riding.
For example, my YB4 literature states you can fit either a 180/55 or a 170/60 section rear tyre.
Note the different heights as this may be why tyres foul.
Likewise Bimota state on the SB6r and the SB8 you can use either a 180/55 or a 190/50 section rear tyre.
What you have to think about is what the changes in size will do to the handling and what your preference is.
What I have found on my SB8 and my 6r was that the 190/50 section rear tyres slows down the handling. In other words easier to ride / more secure / more manageable for the road.
Whereas the 180/55 and the 170/60 speeds things up a little.
Interestingly enough the front tyre on the SB8 is stated as a 120/65 not a 120/70. This 120/65 fitment is very rare and where usually only fitted to Kawasaki 600's and the like.
Again smaller profile means quicker steering. So if someone fitted a 120/60 profile to the front of your bike (on purpose) this is what they wanted, quicker steering.
The YB4, SB6r and Sb8 all have a 5.5 rear wheel, but you can use anything from a 170 to a 190 section but remember the profile (height) is crucial.
So to conclude, it really is your choice; you know how you ride and should therefore chose accordingly.