I'll be ordering some sprockets here in the next couple of days and am considering dropping a tooth or two in the rear. My bike sees mostly highway riding and I'm not concerned about wheelies or quarter mile times.
It's my understanding that most motorcycle speedometers are inaccurate by as much as 5% (conservatively), so I'm thinking that a drop in teeth may compensate for that and make it more precise. Any thoughts on that? Also, as for the sprocket, should I go down one tooth, or two? Would there be any discernable difference with just -1 in the rear? ... or should I go up one in the front?

 

Generally, one tooth in the front is equal to 2 1/2 teeth in the rear. So, if I were you, I would increase one in the front, that will be 2 1/2 in the rear. If you want a noticable difference, I would either add one in the front or two down in the rear. I don't think just one down in the rear is going give you much of a difference.

As for the speedometer, its hard to say what your speedo will be at for error after the change. It very well could be more accurate than it is now, but you will only know after you change your sprockets and either use a gps to measure your speed, or follow someone in a car and have them stay at 55, not really accurate, but its close. Your other option is to get a speedo healer. I think they offer one for your bike. If they do, they run about 100 bucks. Just keep in mind that your speedometer may be off in the other direction after the sprocket change, meaning your going faster than the speedo reads.

 

Thanks for the quick and thorough response Squid. You know a lot about bikes and I value your opinion. Guess I'll just have think about if it's worth it. My logic usually consists of "If it ain't broke, don't fix it" variety.

 

Well, I ended up getting Driven steel front & rear sprockets, 525 pitch at 16/45, a EK MVXZ chain in gold, and a riveting/breaker tool. I'm so excited

 

You just killed what lil bottom end you had. IMO the mpg wont change much because now it will take more effort/gas to get going from a stop.

 

I was under the asumption he did mostly highway riding. In this case, I think he made a good choice. Every 600cc bike I've ever ridden at highway speeds is running pretty high rpms, usually in the vibration zone. Dropping his rpms should smooth out his ride and lower his rpms. I agree it won't do a lot for mpg, but I think it would help a little. If he was in city driving, stop and go, then maybe it would be negatively affected, but for highway driving, its bound to help a little in that area too. But the main thing is going to notice is a nicer, lower rpm ride at highway speeds.

 

True, but why buy a sportbike then lol

 

Went ahead and got it on yesterday (Sunday). The gearing I went with is pretty much stock except it's -1 in the rear (45 teeth). What I didn't consider was that the sprocket diameter would be smaller, thus with a 108 link chain, the axle sits farther back than it would with 46 teeth. Live and learn... What I would suggest is going +1 tooth in the counter sprocket, which I'll probably end up doing, and keep the 45 tooth rear. I haven't had a chance to ride it yet, but I imagine it'll hardly be noticeable.

 

You're right; what was I thinking? I'm going to get rid of my crotch rocket and buy a real bike.
How's a Harley Davidson Road King?

 

Starting to sound like my dad now.. lol but I believe thats an oxymoron. a Real bike and Harley don't go together.. in my book.