I'm converting to 520, using 16/45 gearing. The chain I have is 120 link and stock is 112 I believe. How many links should I chop? I was thinking maybe cut 6 links to leave 114 to make up for the larger rear sprocket. Opinions?
Yeah, I planned to measure, if no one else had a number for me. Definately won't cut 6 six, if you only did 5 with a smaller front. Don't have a press. I'm not going to actually cut the chain. I plan to dremel the pin on the outside of the link and knock it out with a punch. I am however using the press link and not the other master link clip.
For 16/45 gearing, either 112 or 114 links will work. But there are some caveats.
112 brings your rear axle about 1/3" forward. This is fine with a stock shock. But if you are running an aftermarket shock and have added rear ride height (i.e. lengthened the shock to be longer than stock), the 112 may bring your rear axle too close to the shock linkages, in which case you will want to run 114.
The main problem with 114 is that it moves the rear axle about 1/3" back, reducing your range of rearward adjustability for tightening up chain slack, when the chain gets older and begins to stretch. It should be OK though, as long as you don't mind the slight increase in wheelbase.
Whichever you do, make sure you maintain adequate chain slack. More is better than too little. (I keep mine loose enough that the lower run of the chain can be pushed up so that it barely touches the plastic swingarm protector strip.)