I'm going from 38 tooth rear sprocket to 42. I have a DID 520 erv3 chain. How many links do I need to add and is there anyone in the Orlando, Fl area that can help me do this?
A 4 tooth change is fairly substantial, but without knowing the diameters of the sprockets, or an accurate pin to pin distance of a link, I couldn't tell you how much you need to lengthen your chain. In the past I had 2 chains just for situations like this so I could be roughly in the ball park when making a change like that.
I personally wouldn't be too fond of having more than 1 master link in a chain, but that's your call.
It should be fine if
A. your chain is not stretched to much, this will act like a high to low spot
B. you use a rivet style master as opposed to a clip style
The bad thing about not lenghtrning your chain is that you will raise the angle of your swingarm changing your geometry dramatically. It would be better if you did get a longer chain to compensate and have two chains available foryour disposable. Why may I ask are you going up 4 teeth? Is the track you are going to that dramatic of a difference? You might just need to go down one tooth in the front instead of four teeth up in the rear.
2001 Gsxr750 standard gearing is 17/42. Mine was down 1 in the front for 16/42, went to 16/38 for Daytona. Now want to go back to 16/42 for Jennings.