5mph off can be fixed with a gear change. Take the speedo housing/bullet out of the trans, and count the teeth on the driven gear there. Then get a gear that has one less tooth on it to speed up the reading at the speedo.
I do have a speed-o gear tooth count chart posted here somewhere....I'll look for it. It will be just as easy to count your gear, and then change it to what you need, as what it has may be what it is supposed to have to start with, but the tire size difference is throwing the speed-o off a bit.
Speed-o Gear ChartAdams' Apple2008-06-21 18:52:36______________
Joel Adams
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