Put simply, the XT motor runs lean to meet emission controls, this lean running is one of the reasons for the surging. Kev's fuel mod helps because it allows you to richen the mixture by simply turning a dial until the best air/fuel ratio is reached.

With a Kev mod fitted you can go to stage 3 straight away. Without, just stick with stage 1 filter and snorkel removed.

Up to you. Both will improve things. IMHO the Hyperpro springs would be the better solution, but more money/effort. Fork preload spacers (like Kev's) can be fitted easily in 10 minutes. All you have to do is remove the fork top nuts and insert them on top of the springs.

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