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Terry Shepherd Trellis Frame Sportbike Build

Suzuki TL1000 Engine based custom V-twin sportbike

Custom Sportbike TL Left View No Fairing


A few years back a fellow named Art built a bike based on a TLR motor using a Terry Shepherd designed and built frame frome the UK. When finished he had a wet-weight somwhere around 360lbs with street lights, compared to 500 for a stock TLR. He also built up the engine and was putting out somewhere above 140hp.
Art's Bike

Fairing off

I got tangentially involved around the end of 2004, when he was looking for a TRL air-box base-plate with filter. I sent him one gratis, in exchange for being able to see the bike when I drove by someday, as we were starting to plan for the trip in our Sportsmobile.

Then, in late 2005, we were in the area, so I dropped in and got to sit on the bike and chat with Art since I was interested in importing one of the frames and building a similar bike when I settled down (not so much garage room when living in a van).

After settling down in SLC, I had hoped to see Art next summer at the local track, and look over the bike again. With the weak US dollar, I couldn't afford to bring in a new frame, but was hoping things would turn around.

Then in November 2007, after finally getting my TLR out of storage and spending a few wonderful days riding around the mountains (no snow yet), I hopped on TLZone and somehow stumbled on his for-sale thread. Turns out he had crashed at the local SLC track in early September due to a bad borrowed brake-system (lever fell off somewhere in the big front straight), and needed to sell to cover air-lift bills. The bike was well tumbled, but the frame was still straight.

I got hold of him to see if the exotic bits were still available, and was able to drive by and pick up the frame (and associated bits) and brake setup (not the one that broke). The engine was already parted out and scattered across the globe, but the one in my TLR should put out plenty.
Frame kit

With all of that I plan to take the nifty bits from my current TLR (while reverting it pretty much to stock) and build my own light-weight TL-powered rocket-sled.

(I also ended up with my old airbox base and filter coming back as part of the frame kit)


Within the first couple of days after picking up the parts at the end of 2007 I had done a rough assembly to start making a list of the to-dos, and there were a lot:

Frame rough assembly

Coming Along:

More pieces

After some hunting I picked up a set of lightly used Hayabusa Ohlins Road & Track forks with the superbike valving upgrade.

Latest view with Forks

Meanwhile I have been working to get the garage outfitted so that I can move my work out there. Once the it was sealed up I begain work on getting an STM slipper clutch adapted to the TLR motor I will be putting into this bike. More details on its own page for this conversion.

2008-07-13 Looking like a motorcycle:

After the excitement of the last few weeks I had a few hours to work on the bike again. Mainly this was installation of the spare engine to start getting some measurements for bracketry (rear-sets, radiator, battery, etc) and other critical dimensions (chain length, exhaust clearance, sub-frame fabrication).

Right Side Left Side


2009-01-16 All the major components on:

The last few months have seen the construction of the sub-frame, rearsets, and various other small brackets. The fairing (a used CF/Kevlar Sebimoto unit) was obtained, and I have started working on fitting it to the bike.

I also picked up a new rear spring (titanium, all of 490g), some lithium cells to build a starting battery, and some Woodcraft pegs and levers for the rear-sets.

I still need to come up with some exhaust hangers and a battery box to hold the new starting battery (2lb vs about 8 for the standard lead acid).

I also had a chance to weigh it with everything piled on (chain, electrics, fuel-pump) and ended up at 325lb. This would indicate a wet weight of around 365-370lb with a full tank of gas and a few lbs allocated for lights.

Left Side Right Side Front Back

2009-02-19 Subframe roughed out:

My initial pass at the subframe is done. I still need to do some joint reinforcement with some carbon-fiber thread and resin, but the basic shape and angles are all in place and tacked with aluminum brazing rod. The seat-fairing section sits on a small aluminum frame not-pictured that allows for fine-tuning of the seat inclination angle.


2009-02-22 Starting battery:

I finally got around to soldering up the lithium cells to build my starting battery. As is it weighs in at 2lb 0oz, compared to about 8lbs or so for the stock battery. It should have comperable capacity. I have some terminals on order, and will then wrap it up to keep it clean and insulated. I have enough spare cells to build another one with 2/3 the capacity and weight, if it proves sufficient.

2009-02-25 Airtubes formed:

I spent a lot of my free time in the last few weeks preping to make the air-tubes. Since the frame is custom and the fairing is from a TLR, there are no commercially available airtubes that will work well with the fairing and get the air to the airbox.

The airbox I received with the frame seemed designed to take the air in from just behind the steering stem with a small spout that pointed down to the back of the front tire. I did not like this as it seemed a good way to get crud off the wheel, hot air from the radiator when stopped, and did not take advantage of the air-tube scoops on the fairing.

I decided to make carbon-fiber tubes to lead from the fairing inlets to the sides of the airbox. This gave me the excuse to purchase a vacuum pump and build a vacuum bagging system for this and future composite parts.

Details of the composite construction on its own page.


2009-05-04 - Test Assembly:

Since the last update I have managed to get quite a bit done:

  • Have built a new CF airbox to replace the mangled one from Art. It came in at 308g vs 790b for the one it copied, so that was an additional benefit.
  • The rearsets are finished except for anodizing (which I will do after everything has been tested incase I need to adjust them).
  • Air-tubes are trimmed and fit to the airbox, but still need clearcoat when I spray everything.
  • Projector headlights are mounted and wired in.
  • Steering damper mount and frame anchor finished.
  • Wire-harness sorted, and routing determined. Handle control wires and front harness shortened as needed (there is a lot of unnecessary wire in the front harness/control pods area)
  • Computer/RR/PCIII mount constructed.
  • Subframe finshed and painted
  • White paint on the fairings stripped off, cracks repaired, and paint-prep begun (fairings will be clear-coated).

So here are a few teaser pics to fill some space:

Side view

Side detail

Final Assembly:

I spent the last couple months taking care of all the little niggling aspects that were bugging me: Modifying the fairing for headlights; repainting the frame, swingarm, tank; clearing the fairing, rims, and air system (makes the carbon really "pop", and protects from UV); re-fabricating brackets I wasn't happy with, and setting up all the wiring and lighting.

This weekend I started up the final assembly, torquing all fasteners and being quite liberal with the lock-tite. Once I have verified the tank is sealed at the pump, I will mount it up and see if it actually runs.

Frame with Engine

Custom Sportbike Construction Finished


CRG Clutch Lever


First Ride:

First Ride on Terry Shepherd Custom TL


First Track Day:

First Track-Day on Terry Shepherd TL
(Photo by Stephen W. Clark)


345lbs without fuel. 370lbs with 4 gallons.


  • Terry Shepherd tuning TL1000 frame kit - www.terryshepherdtuning.com
    • Trellis frame
    • Aluminum tank (spare that wasn't in the crash)
    • Modified '99 GSXR750 swing-arm
  • Self-built aluminum sub-frame
  • GP-Tech aluminum fairing stay
  • Gilles chain adjusters and stand hooks ('99 GSXR750)
  • Self-built rearsets with CFM Woodcraft pegs and pedals
  • Titanium swingarm pivot axle (TiN coated) with matching aluminum lock-nuts
  • Custom-made aluminum kick-stand (8oz)


  • Ohlins remote reservoir rear shock with hydraulic preload adjust
  • Titanium rear shock spring with Torrington bearing- www.traxxion.com
  • Ohlins R&T 43mm forks
  • Attack adjustable triple clamps (modified to use Scotts rotary steering damper)
  • Scotts rotary steering damper
  • Dymag full carbon fiber 3-spoke rims, 17x3.5 front, 17x6 rear
  • CFM Woodcraft clip-ons
  • CRG Supersport clutch lever & perch


  • PFM race-kit front 6 piston calipers & rotors - www.pfmbrakes.com
  • Brembo 19x20mm radial front master cylinder
  • AP CP4226 2 piston rear caliper
  • Brembo rear master cylinder (R6)
  • Braking Wave rear disk





  • Ground to headstock bottom center, unloaded = 758mm
  • Ground to swingarm pivot center, unloaded = 401mm
  • Ground to front drive sprocket center, unloaded = 396mm
  • Swingarm Length = 520mm
  • Wheelbase = 1448mm
  • Fork offset = 31mm (TS suggested 29mm, I didn't have such inserts, and am already seeing tire rub on front cam cover)
  • Fork spring rate: 8.5 N/mm
  • Rear sping rate 555 lb/in
  • Sag about 25-30% of travel, front & rear
  • Rear shock length 300mm, 45mm travel
  • Rear shock-SA pivot R1 240mm, R2 260mm : Progressive 15% at full bump to full droop


(Photo by Stephen W. Clark)