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rigor
07-04-06, 09:29 AM
Had some new rubber fitted yesterday. Got the bike home and noticed that they have fitted a 120/70 on the front, as opposed to the 120/60 that was the size of the standard Dunlop.

Is this going to cause me any problems, and should I get them to swap the tyre? Or will it be fine?

Thanks

Rigor

21QUEST
07-04-06, 10:43 AM
Had some new rubber fitted yesterday. Got the bike home and noticed that they have fitted a 120/70 on the front, as opposed to the 120/60 that was the size of the standard Dunlop.

Is this going to cause me any problems, and should I get them to swap the tyre? Or will it be fine?

Thanks

Rigor

It's not goiing to cause you any problems as such. The bike would be a bit more stable(argueably too stable).

You could drop the forks down a bit to offset that but you should not have to as you did not ask for a 120/70. They have made a c**kup and should rectify the the situation.

Get them to swap them over to the OE size.


Cheers
Ben

Edit: Could possibly be a problem :) For example you are used to applying a certain amount of force on the bars to turn the bike(120/60). Someone puts in 120/70 you apply you force on the bars and :shock: bike does not do exactly what you'd expected. You to run wide etc since you have applied to little force to the bars cause of the change in setup.

Not trying to get you worried .... :wink:

Flamin_Squirrel
07-04-06, 11:32 AM
I found fitting a 120/70 sped the steering up, not the other way round.

andyaikido
07-04-06, 11:33 AM
Possibly an insurance issue too.

jonboy
07-04-06, 11:50 AM
I found fitting a 120/70 sped the steering up, not the other way round.

The tyre profile will have a big say in this though. TBH I'm going to fit a 120/70 next time around, as I'm interested to see if it's an improvement on the 120/60. If it's fine for SS600s of the same weight then I'm sure it's more than good enough for the SV, and the insursance companies can get stuffed as I don't believe an objection to such a small "improvement" would hold sway in court (if it came to it).


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Flamin_Squirrel
07-04-06, 01:17 PM
I found fitting a 120/70 sped the steering up, not the other way round.

The tyre profile will have a big say in this though. TBH I'm going to fit a 120/70 next time around, as I'm interested to see if it's an improvement on the 120/60. If it's fine for SS600s of the same weight then I'm sure it's more than good enough for the SV, and the insursance companies can get stuffed as I don't believe an objection to such a small "improvement" would hold sway in court (if it came to it).


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True, but whatever way you look at it the tyre has to get more pointy, thus giving faster turn in.

jonboy
07-04-06, 01:43 PM
No not necessarily (and this was argued successfully in a thread from last week or the week before). The profile makes a big difference and just because the tyre is taller doesn't mean it's got a sharper profile. And because the sidewall is taller, and thus has more flex, it can actually slow the steering down a tad.


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northwind
07-04-06, 01:48 PM
It'll also make the speedo close to accurate.

Last Action Pimp
07-04-06, 01:50 PM
I am going to fit a 120/70 next time (its one i can get cheap) also my manager reccomend it and says that many of our customers like the 70 over the stock 60

21QUEST
08-04-06, 08:43 PM
I found fitting a 120/70 sped the steering up, not the other way round.

The tyre profile will have a big say in this though. TBH I'm going to fit a 120/70 next time around, as I'm interested to see if it's an improvement on the 120/60. If it's fine for SS600s of the same weight then I'm sure it's more than good enough for the SV, and the insursance companies can get stuffed as I don't believe an objection to such a small "improvement" would hold sway in court (if it came to it).


.

True, but whatever way you look at it the tyre has to get more pointy, thus giving faster turn in.

In theory. Everything being equal as in leaving aside overall tyre profile as two different tyre with identical marking may not necesarily be the same height etc.

A 120/70(in theory) will be 12mm taller than a 120/60 which would raise your front ride height. Therefore since one would usually drop the front to quicken the steering , raising the front be it with a taller tyre would slow the steering :?:

Also the 120/70 would increase your trail by about 6mm. More trail would equal more stability :?: .

Golden rule 'Every change has an impact on something else' :wink:.


Greg , just curious about what sort of improvement are you looking for/problems you having with the 120/60.

XVS2005 :) also interested in why your manager is recommending a 120/70. Is he actually backing up his recommendations?


Cheers
Ben

setanta
09-04-06, 02:33 AM
So fitting these tyres would mean higher seat????
B) Whats wrong with the 60s

daddy_sperm
09-04-06, 05:56 AM
So fitting these tyres would mean higher seat????
B) Whats wrong with the 60s

I doubt you would notice any difference in height...

21QUEST
09-04-06, 09:05 AM
So fitting these tyres would mean higher seat????
B) Whats wrong with the 60s

I doubt you would notice any difference in height...

More to do with the front ride height and agree that you probably won't notice much difference in seat height. The most important bit though is how it affects the overall geometry/ride.

With regards to 'B' , hmm... good question :?: :D

Cheers
Ben