My sprocket has lived up to....living. I have so many broken and worn teeth that it is time to go. My question is:

Is it bad to go to a quality 520 chain / sprocket combo in the stock 15/43 size if the stock chain is a 525? Am I going to encounter any problems?

Thanks!

 

Going from 525 to 520 to me is not worth it. You would probably have to put your bike on a dyno before and after to be able to measure the difference. In real world applications on the street, it's not going to be that noticable.

 

I just used my butt Dyno and there is a difference.
My stock sprockets were still good but the chain had seen better days since the previous owner had it on a carport for a few months. I guess all the moisture created the rust and tight spots. I always wanted to try -1 on the front so I also went with the 520 (steel) sprockets. They are not as light as the alumium but will last longer. This is one of the cheapest mods you will do for your bike where you will actually notice it. If you don't mind more rpm's and lower top speed you also should try +2 on the back.

 

Well, it's hard to put a number on you "Butt" dyno. But, (pun intended) changing the number of teeth on the sprockets will make a difference that is easily noticable.

 

but its cheaper...does this make it worth it? im investing in a quality RK chain and some vortex sprockets so im not going to see any problems coming down to a 520 bike-wise right?

 

I would say stay with the 525 n just change tooth count, on the street you really wont notice the diff between the 525 n 520. Def dont go with aluminum, and make sure to change it all out as a set to avoid premature wear.

 

I think the answer that you are looking for is, no. you will not cause your bike harm due to a change in sprocket/chain size. it is a very common bolt on for people that are looking for a little more low end grunt at the expense of their top speed, and luckily, due to the fact that the speed sensors in the F3 aren't based on the rotation speed of the front sprocket but from an electrical signal from the engine, you wont even have to worry about your speedo being thrown off like in the newer bikes.

 

Are you sure about that speedo? cause mine is off... unless mine is just retarded to begin with

 

they're all off a lil even driven by the front wheel. Running a diff size tire than stock will do it too

 

thanks for the backup PG. now to back him up a little. all speedos are off by about %10 from the factory, to the faster side. additionally, there are a lot of things that you can do to your bike to further exacerbate the problem.