Triumph valve guide reamer .3115"
Using premium hardened High Speed Steel, Kibblewhite specifically designed this valve guide reamer to size manganese bronze (C67410 bronze) and cast iron valve guides. These spiral fluted reamers have a one inch pilot to center the reamer, and has a cutting tolerance of ±0.0002".
This is a perfect tool to correctly size Triumph guides for Kibblewhite valves, as the exhaust valve stems are .0005" smaller than the intakes, and correct clearance for both valves can be obtained by sizing all guides to .3115"
After installing and reaming the guide in the cylinder head, it can then be finish honed with a flex hone in a drill. The seat can then be cut as needed.
PLEASE NOTE: Do not attempt to use this reamer to size C630 bronze guides. Also, once a reamer is used on cast iron, it is not advisable to then use it on a bronze guide.