click around the wiki for stuff about your bikes... You can make it run better on your own, but unless you actually plan to put a decent amount of time and effort into the bikes (and a lot of it involves reading things that are already out there), then you're not going to make much headway.
More air + More Gas = More fast. If you can get more air/fuel mixture in, then you'll get higher RPMs.
You might also break it.
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