a clutch upgrade is a must. One point on springs: no need to go Barnett (43% stronger). Very heavy and will actually wear out the clutch actuator nylon bushing. Barnett is what I wanted to get and MMM ar 650central talked me out of it. Sold me Vesrah springs (14% stronger) and EBC fiber plates. No slippage on my 52hp build.I went with the yamahxs650 big bore kit and am very happy with it. Lessened the vibes a significant deal and pulls REALLY well. It’s not going to win any speed awards, but for my little back road racer it does great. I had plans to do a cam, port work and new carbs, but honestly right now it runs so well for me with the tuned carbs that I’m leaving it alone. Whenever I need more work done that may change. Might I also suggest saving up a little money and upgrading your clutch as well?
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