Obviously, you don't have to have a tach to know when to shift, etc. BUT, I've loved having mine which was installed when I bought the bike. I think they should all come with one anyway.
It is helpful in making adjustments on the bike, balancing carbs, adjusting the idle and just a reference to know things are the way they should be. I especially liked it after installing the Big Bore kit as all my "learned" instincts shifted a bit because the entire pitch of the engine changed.
To sum up, I like the way it looks on the bike and think it's worth every penny - wouldn't have it any other way.
