'99-'01 Speed Triple intake valve guides

OEM on the left, aftermarket on the right

The combination of very short guides with excessive clearance as new leads to excessive guide wear. This stock guide has .0033" of clearance after only approximately 8K miles. For reference, the specification is .0004" to .0016", with a service limit of .0027". In my opinion, .0016" is already far too much, and wear will ensue rapidly. Loose clearances cause excessive wear to the valve face, and increase oil consumption. Fitting longer guides with a tighter clearance will reduce wear and increase longevity.

worn valve

new valve

valve unshrouding

valve springs

exhaust inlet to port matching

wrist pins

under-tail exhaust

dyno chart

low mount mirror bracket

motorcycle (prior to low mount mirror conversion)