A Couple of Bucks probably has your low end performance improved, an 1/8 low in the secondary is like taking off in 2nd gear like was mentioned.
With that being said, if you've never taken the clutches apart and cleaned them you are leaving quite a bit of performance on the table. The Tech pages will have some good tutorials/instructions. The primary requires a puller, but just blowing it out with air and using a green scotchbrite pad in circular motions on the sheave faces does a pretty good job. The secondary is best to pull clear apart. The hardest part for someone new is putting the secondary back together correctly, there are settings for each end of the spring that need to be put back where they were and you have to make sure it is "wound" correctly so that the helix ramps are sitting on the buttons. The buttons are a wear item and easily replaced, they just pull out and push the new ones in. Green scotch brite pad on the sheave faces of it too. Just warm soapy water is better than a parts cleaner or anything that will leave an oily residue on the sheaves. Many (while their wives are gone) throw the clutch(s) through the dishwasher.
A story to maybe help motivate you lol.
Years ago I bought a used '93 Exciter ll SX. Itching to ride it, I loaded it up and headed out a couple of days later without going through the carbs and clutches like I know I should. A good friend went along that had a stock Phazer except that he had put a 129" track on it and geared it down a bit. I was used to Phazers and found the Exciter to be kind of lackluster in comparison, I thought it would have quite a bit more pep. Towards the end of the day my friend wanted to drag race so we lined them up. He absolutely torched me, out of the hole about 2 lengths and then in mid range and on top he was steadily pulling away. We both knew that wasn't right. The next week I pulled the clutches. It was obvious that the original owner had never cleaned them. There was tons of belt dust in the secondary and the buttons were very worn down. I cleaned it and put new buttons in. The primary...wow. There were strands upon strands of belt threads and tons of dust. Removed all of it and cleaned it as well. The sled was also rich in the mid range and I lowered the needles one position.
The next weekend I went riding again with the same buddy. We lined the sleds up again and this time I just flat left him from the word go...3 different runs.
