'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.
exhaust inlet to port matching
low mount mirror bracket
motorcycle (prior to low mount mirror conversion)