Velopedia Bicycle Archive
2000 Boulder Bikes Sirius
Original specifications: Shimano XTR · 7-speed · mechanical rear derailleur · 20" wheels · 46 lb published weight.
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At a glance
- Model year
- 2000
- Category
- Tandem
- Original MSRP
- $5,499.00
- Sizes
- Adjustable for rider height
- Colors
- Buyer's Choice
- Weight
- 46 lb
- Geometry
- Legacy reference
- In this record
- 27 specifications · original MSRP · geometry
- Archive ID
- 49008
Original build7005 aluminum, butted w/replaceable derailleur hanger · Recumbent Mix · 20" wheels
Frameset
| Frame Construction | TIG-welded |
|---|---|
| Frame Material | 7005 aluminum, butted w/replaceable derailleur hanger |
| Fork | Ballistic 600 XL, 1.0" travel |
| Fork Material | Aluminum/chromoly, triple-clamp crown |
| Rear Shock | Works Performance/Boulder Bikes Spring/Oil, 3.0" travel |
Drivetrain
| Component Group | Recumbent Mix |
|---|---|
| Shifters | SRAM Quartz |
| Front Derailleur | Shimano Ultegra, bottom-pull/clamp-on 31.8mm |
| Rear Derailleur | Shimano XTR SGS |
| Crankset | Sugino XD600 Tandem, 38/50/60 teeth |
| Bottom Bracket | Shimano BB-UN72, 122.5mm spindle |
| BB Shell Width | 68mm English |
| Rear Cogs | 7-speed, 11 - 30 teeth |
| Chain | SRAM PC-61, 1/2 X 3/32" |
| Pedals | Not included |
Brakes
| Brakes | Magura HS 33 brakes, Magura levers |
|---|
Cockpit & Contact Points
| Headset | 1" threadless Chris King NoThreadSet |
|---|---|
| Handlebar | RANS Tilt Bar-Stem Combo |
| Stem | RANS Tilt Bar-Stem Combo |
| Saddle | RANS recumbent seat |
| Seatpost | Control Tech Control Post |
Wheels & Tires
| Hubs | Front: SRAM Plasma, Rear: SRAM 3x7 |
|---|---|
| Rims | Sun Rims CR18, 32-hole |
| Spokes | DT stainless steel, 2.0mm straight gauge |
| Spoke Nipples | Brass nipples |
| Front Tire | 20 x 1.50" |
| Wheel Size | 20" wheels |
Geometry
Model-level measurements; the frame size was not recorded. Use these as a historical reference, not for size-specific fit.
Reference frame view
Select an available measurement to locate it on the frame.
All geometry measurementsLegacy reference · 3 measurements
| Measurement | Legacy reference |
|---|---|
| Head-tube angle | 72° |
| Wheelbase | 740 mm |
| Fork offset / rake | 38.1 mm |
The preserved source contains one model-level geometry set without an identified frame size.
Gearing
Lower ratios provide more mechanical advantage for climbing. Higher ratios turn the rear wheel farther with each crank revolution.
Parts & serviceability
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More parts (1)
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Bike-specific inspection checklist 22 checks based on 6 archived component groups Open checklistClose checklist
This checklist uses the archived equipment for this bike. It cannot confirm the condition, service history or later component changes of the example in front of you.
Identity and fit
Follow the full used-bike inspection order →Archived: 2000 Boulder Bikes Sirius · Tandem (recumbent) · Published sizes: Adjustable for rider height
Frame and fork
Inspect the frame and fork →Archived: Frame: TIG-welded · Fork: Ballistic 600 XL, 1.0" travel · Aluminum/chromoly, triple-clamp crown
Suspension
Evaluate the suspension →Archived: Fork: Ballistic 600 XL, 1.0" travel · Rear shock: Works Performance/Boulder Bikes Spring/Oil, 3.0" travel
Drivetrain
Check drivetrain wear →Archived: Group: Recumbent Mix · Shifters: SRAM Quartz · Front derailleur: Shimano Ultegra, bottom-pull/clamp-on 31.8mm · Rear derailleur: Shimano XTR SGS · Crankset: Sugino XD600 Tandem, 38/50/60 teeth · Bottom bracket: Shimano BB-UN72, 122.5mm spindle · Rear cogs: 7-speed, 11 - 30 teeth · Chain: SRAM PC-61, 1/2 x 3/32"
Brakes
Inspect the brakes →Archived: Brakes: Magura HS 33 brakes, Magura levers
Wheels and tires
Check wheels and tires →Archived: Wheel size: 20" wheels · Rims: Sun Rims CR18, 32-hole · Hubs: Front: SRAM Plasma, Rear: SRAM 3x7 · Front tire: 20 x 1.50"
Controls and contact points
Archived: Headset: 1" threadless Chris King NoThreadSet · Handlebar: RANS Tilt Bar-Stem Combo · Stem: RANS Tilt Bar-Stem Combo · Seatpost: Control Tech Control Post · Saddle: RANS recumbent seat · Pedals: Not included
Before and during the test ride
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Specifications are presented as a reference. Components may vary by market, size, production run, or later manufacturer revisions.
