Attic Rat Performance Works · Tulsa, Oklahoma
GLH
REGISTRY
The official historical record of Honda Valkyrie motorcycles modified with the GLH performance engine package by Bob Smith. 1997–2003.
The Package
Three Levels of GLH
The first six Valkyries used to test and develop the GLH engine package. These are the founding bikes of the registry.
Find Your BikeBob's core engine package: milled heads, ported and polished intakes, jetting tweaks, fly-cut pistons, and proprietary tuning refinements.
Additional Decking and Jetting.
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The Origin
Bob Smith.
Attic Rat Performance Works.
Tulsa, Oklahoma.
Bob Smith at Attic Rat Performance Works in Tulsa, Oklahoma built a small number of Honda Valkyrie motorcycles with his proprietary GLH performance engine package.
Each bike was modified to Bob's exacting standards. The GLH package transformed the already-capable Valkyrie into something genuinely extraordinary — a machine built to go like hell.
This registry exists to document every known GLH build, preserve their history, and connect current owners with the legacy of these remarkable machines.
Own a GLH?
Is Your Bike
In the Registry?
If you own or know of a Honda Valkyrie with the GLH performance package, help us complete the historical record.
Already in the registry? Find and claim your bike.
Search the Registry