170 on 4.5 Rim

[750Monster43]

Seems to be a 50/50 debate as to going to a 170 on a 4.5 rim.

My 01 750 has a 160 M3 Metzler.  Put a new M5 on the front last fall, and is getting to the point of putting the same M5 on the rear.  Would like to move up to a 170 - mostly for the look to be honest ... as I think the 160 is slightly narrow.  90% urban bike - rarely get out on the highways.

Would moving to a 170 be ok - or play it safe and stick with the 160?

Not too aggressive anymore ... haven't even hit the chicken strip bars on the M3's ... so won't be too concerned if a tad slower turning in.

Thanks in advance.

[DarkMonster620]

Stick with the 160 . .  the 170 would get "too round" on the running surface and make the bike "slower" even on urban enviroment . . . tried it on my 620 with a friend's 170 & 180 . . . plus, you would need more power to move the bike

my $0.02

[Howie]

You would also slightly increase the radius of the tire since the profile stays the same.  I wouldn't call it unsafe.  Dunlop's recommendation for a 170 tire is a 4.5' wheel.  Me, I agree with  Darkmonster620's opinion on performance loss and wouldn't do it.  Oh, more unsprung weight from a bigger tire too.

[DarkMonster620]

You would also slightly increase the radius of the tire since the profile stays the same.  I wouldn't call it unsafe.  Dunlop's recommendation for a 170 tire is a 4.5' wheel.  Me, I agree with  Darkmonster620's opinion on performance loss and wouldn't do it.  Oh, more unsprung weight from a bigger tire too.

Correct howie . . . but, Metzeler's I've notice "tend to run wider" . . . and yes, the weight