Hey guys...quick question. Ordered a new set of tires for my 2007 R1200GS Adventure. Ther bike is new to me; had it about 1.5 months and purchased manufacturers recommended sizes but when I actually looked the tires on the bike noticed they were both wider (170 vice 150 on rear and 120 vice 110 on front). My question is this...was the decision based on historical knowledge of the handling characteristics of this particular bike or purely preference? I have always purchased the recommended sizesd on every bike I have owned but curious if anyone has any anecdotes to share. Thanks guys!! T
In my experience, most of the time tires are oversized is simply because the previous owner thought that they look better or that somehow the bike will work better with wider rubber. I'd recommend starting off with a new set in the stock sizes and see how it goes. The bike was designed with those sizes, and will almost certainly work better.
That’s pretty much what i figured; that it was a question of aesthetics more than anything else. From my experience, wider tires have always resulted in decreased maneuverability. Does it increase confidence on the road?? Maybe...by to me not worth the trade off.
You're right about the decreased maneuverability. Putting too wide a tire on a wheel can result in the beads getting pinched in, resulting in a more triangulated tread profile. This can make turn-in wonky, and will do nothing good for tire life. It can also make the steering feel twitchy and nervous. Wide tires are fantastic on bikes that can exploit their benefits. Most ADV bikes don't fall into that category.
Sometimes primitive four-wheeled vehicles can benefit from wider tires, but you can't apply that sort of caveman thinking to fine two wheeled machinery. There are a few sportbikes with really wide rear wheels where you can vary the rear tire width a little for different handling effects. Install the correct sizes and enjoy how much better the bike handles!
The previous owner or the shop screwed up. 120-170 is the tire size for the 2014-on models. It will not handle very well with those sizes on your narrow rims. You may get some high speed wobbles too. Go with the 110-150.
I highly doubt you'll notice the small difference in the tire diameter on your GS. What ratio is the tire as well, touring pavement tires are better with a smaller ratio, where a dirt tire is better with a higher ratio. Some tires aren't available in some sizes too. Putting a wider tire on a rim adds more curvature to the tire profile which then translates into a tire that is more difficult to deform, you have to hit something much harder to bend your rim.
