I can't comment on any bike other than my own but in my experience it's unlikely you'll ever truly top out your bike on standard gearing, but if you drop a tooth on the front you'll have enough extra pull to get you properly topping out, so whatever top speed you lose by dropping a tooth you will almost completely make up by using them extra revs, plus get a nice bit more acceleration. I won't bore you with the details but my bike lost 2mph top speed (in reality) when I dropped a tooth on the front but got a 6.66% increase in acceleration (in theory), which is well worth it. I temporarily swapped back to my standard 15t front sprocket and it was noticeably slower on acceleration. I hope that's some help
Im running -1+2 on my 14. I'm really enjoying it. You notice the acceleration increase for sure and your front wheel will lift with very little effort.
However your top speed drops to around 255 kph but it's easily reachable your rpm increases by roughly 650 rpm at 100kph and if you use traction Control it will be far more active In the lower gears due to the torque increase.
I personal havent noticed a increase in fuel economy
I think it's worth a go. The gears are relatively inexpensive and not hard to change with the right tools and if you get both gear you can try different variations to see what works best for you.
I have a 2014 myself. The 1st 1,000 miles, I rode with the stock gearing. 1,000-4500 miles, I rode with a -1 front sprocket and +0 aluminum sprocket. This year, I changed the rear sprocket to a +2. So now this year I'm running a -1/+2 setup. I will say that this is by far the best, most accelerating, Holy Shit Batman setup you can really get. Any more than this and you can't really do WOT without the front end coming up all the time. If I pull on the throttle in 1st gear, it will come up easily. 2nd gear, I can get the front end to come up easily too. The newer 636's have so much more low and midrange power that anything more than -1/+2 sprocket just might be unmanageable.
I noticed a significant decrease in fuel economy. At an indicated 80mph cruising, I'm at 8krpm. It's no longer a bike I want to take on longer trips due to this higher gearing.
A -1 front only gave me a little extra ooomph and made the front tire come up off the ground easier and is very manageable. I liked it. I honestly think going up 2 teeth in the rear gave a more noticeable difference than just going down 1 in the front. I believe the math is a -1 in the front is comparable to +2 in the rear (some say its +3.)
My top speed has gone down significantly too. I was able to crank out 176 mph indicated. I had about 1,000rpm still to go. I did that once and won't do it again. I don't think I can honestly get the bike over 150mph indicated (roughly 140mph true speed)
Just depends all on what you are wanting to do. I'm taking my bike to a track and its not a high speed track, so I would never get into 6th gear anyway. I say for the street, it's fun. If you do alot of highway, a -1/+2 is bad.
Go with a -1/+2. If you don't like it, you can always put your stock rear sprocket on and cut your chain back to the length.
Or you can try just the -1 in the front and I believe you can keep the stock chain. Anytime you change sprockets, you want to change your chain though if you have put some miles on it.
-1/+2 I had to do 114 links if I remember correctly. It might have been 116