The Story
ATTIC RAT
PERFORMANCE
Between 1997 and 2003, a small shop in Tulsa, Oklahoma quietly built some of the most distinctive Honda Valkyries ever to roll out of a garage. This is that story.
Attic Rat Performance Works
Tulsa, Oklahoma
The Builder
Bob Smith & Attic Rat Performance Works
Bob Smith ran Attic Rat Performance Works out of Tulsa, Oklahoma — a one-man operation with an outsized reputation among Honda Valkyrie enthusiasts. Bob wasn't building bikes for showrooms. He was building them for riders who wanted something more: more power, more presence, more personality.
The Honda Valkyrie — produced from 1997 to 2003 — was already a formidable machine straight from the factory. A flat-six engine, low center of gravity, and a cruiser silhouette that turned heads on any highway. Bob saw it as a canvas. His GLH engine package transformed stock Valkyries into something genuinely rare.
"Every bike that came through the shop got the same attention. Didn't matter if it was number one or number one hundred — it left better than it arrived."
The Modification
What Is the GLH Package?
The GLH is Bob Smith's signature performance engine package for the Honda Valkyrie — built around roughly 100 bikes over the years. It's engineered to significantly boost power and throttle response while keeping the bike reliable and enjoyable for real-world riding, not just a dyno number.
Bob worked directly with each owner, but every GLH left the shop with the same fundamental engine transformation: decked heads, ported and polished intakes, jetting tweaks, fly-cut pistons, and a collection of proprietary tuning refinements he's dialed in over years of builds.
Decked Heads
Precision material removal from the cylinder heads to raise compression and improve combustion efficiency.
Ported & Polished Intakes
Intake ports reshaped and smoothed to maximize airflow into the combustion chamber.
Jetting Tweaks
Carburetor jetting recalibrated to match the increased airflow and compression of the modified engine.
Fly-Cut Pistons
Done to ensure adequate piston-to-valve clearance. It is primarily done to prevent the valves from physically striking and destroying the pistons during engine operation.
Proprietary Tuning
Additional refinements Bob has developed and refined over years of GLH builds — his edge.
The first six Valkyries used to test and develop the GLH engine package. These are the founding bikes of the registry — the bikes Bob built the package on.
Additional Decking and Jetting
Bob's core engine package: decked heads, ported and polished intakes, jetting tweaks, fly-cut pistons, and his proprietary tuning refinements. Every GLH left the shop with significantly more power and better throttle response.
Timeline
Seven Years of Builds
The First Six
Bob completes the first six GLH builds — the Original Six. The Honda Valkyrie has just entered production and Bob sees its potential soon after. These bikes establish the template for everything that follows.
Word Spreads
Valkyrie owners across the country begin hearing about the work coming out of Attic Rat. Orders increase. Bob refines the GLH package,
Main Production
The busiest years at Attic Rat Performance Works. Bob is building GLH bikes steadily, each one documented with an invoice. The registry estimates roughly 100 bikes were completed during this period. In 2021 The Only GLH Plus bike is built. This was a frame up build known as The Red Rat.
Attic Rat Performance
Bob continues to provide maintenance services for first-generation Valkyries. From time to time, he comes across exceptionally low-mileage bikes and meticulously restores them for enthusiasts who want an almost-new first-generation Valkyrie (1997–2003).
Although he still receives offers to build "just one more" GLH, Bob is no longer performing complete performance-package builds. As a result, GLH-equipped Valkyries have become highly sought after, with their rarity and value continuing to increase over time.
The Registry
Decades later, GLH Valkyries are scattered across the US, Canada and other countries — some still with original owners, others traded hands multiple times. This registry exists to find them, document them, and preserve their history.
Why It Matters
Preserving the Record
Bob kept invoices. Every GLH build that left Attic Rat Performance Works was documented. Those invoices are the gold standard for verification — a bike with an original invoice is a Verified bike. A bike reported by an owner or community member without documentation is Reported, pending further evidence.
The goal is simple: account for all ~118 GLH Valkyries believed to exist. Find the bikes, document the ownership chain, and create a permanent record that honors the work Bob Smith did in that Tulsa shop.
Verified
Confirmed against original Attic Rat invoice records.
Reported
Submitted by an owner or community member — awaiting documentation.
Join the Registry
Do You Own a GLH Valkyrie?
If you own or know of a Honda Valkyrie with a GLH package from Attic Rat Performance Works, we want to hear from you. Every submission helps complete the historical record.