The Tumbleweed Sunliner is a flat bar rigid 29er mountain touring bike. It’s in the same brand family as the lauded Stargazer. After crowning the Stargazer best in class, John had to try out the flat bar sibling to see if it stacked up. While we have a much longer, in-depth review on the way later this fall, let’s take a First Look at this tantalizing touring bike…
Tumbleweed Sunliner Quick Hits
Frame Specs:
- Sizes: Small, Medium, Large, Extra Large
- Frame and fork $1400
- Standard Spec complete build $3775
- Tubing: Heat-treated, size-specific Cromoly tubing. Oversized triple and quad butted main triangle with integrated gussets
- Colors: Forest Green or Rhubarb (dark pink). Both with gold Tumbleweed graphics
- Tire Clearance: Optimized for 29 x 2.6”, clearance for up to 29 x 3″ (Tested with WTB Ranger tire on 40mm internal rim width)
- Head Tube Diameter: 44 mm I.D. for ZS44 upper, EC44 lower cups
- Bottom Bracket: 73 mm BSA threaded
- Spacing: Boost 148 mm x 12 mm thru axle (included)
- Seat Post Diameter: 31.6
- Seat Collar Diameter: 35 mm (included)
- Dropper routing: External routing on down tube with internal routed seat tube
- Driveline: 1x drivetrain specific. Not designed to accommodate a front derailleur
- Chainring Clearance – 38 tooth max
- Brake Compatibility – 180 mm or 160 mm IS mount, front and rear with external cable routing
- H20 mounts – One set on seat tube, one 3 pack mount on top of downtube, one 3 pack mount under down tube (Small has 2 mounts on top of downtube)
- Rack and Fender mounts
Fork Specs:
- Tire Clearance – 29 x 3 (Tested with WTB Ranger tire on 40mm internal rim width)
- Spacing: Boost mountain – 110 x 15 mm thru axle (included)
- 3 pack mounts angled rearward
- Low rider rack mounts
- Upper fork crown rack mounting points
- Center hole on fork crown
- Generator wiring port on lower right leg
- Rack & Fender mounts at dropouts
- 440 mm Axle to Crown with 55 mm offset
Same-ish Chassis, Different Bars
The Stargazer is a boost front and rear-spaced drop-bar 29er mountain bike with plenty of touring mounts. It’s my go-to for referrals when people ask my opinion on a production, non-suspension-corrected drop bar touring bike. While I enjoyed the high stack and comfortable riding position the Stargazer offered with its wide drop bars, I still prefer a flat bar for double and single track touring and riding.
When I asked Daniel from Tumbleweed how this bike fits into the company’s lineup, he replied:
“We designed the Sunliner for two specific groups of customers: those asking for a Prospector with a derailleur spec, and those asking for a Stargazer build with a flat bar…”
Taxonomy: What is the Sunliner?
Like the Stargazer, the Sunliner is boost-spaced front (110 mm) and rear (148 mm) with a 73 mm bottom bracket shell as such, it is a rigid 29er mountain bike. It uses a mountain bike drivetrain and has proper mountain bike tire clearances and both fender and rack mounts. For all intents and purposes, it is a mountain touring bike.
When Daniel from Tumbleweed told me he was working on a flat-bar Stargazer, dubbed the Sunliner, I expressed an interest in riding and reviewing one. I truly believe the rigid 29er is one of the best “all-rounder” platforms, and I was curious if the Sunliner would make for not only a great touring bike but also a great trail bike for our more XC-oriented singletrack here in Santa Fe.
The Sunliner dons a new head tube badge from Tumbleweed Bicycle Co.
For the past few months, I’ve been riding the Sunliner as an all-terrain bike, and with today’s announcement, I wanted to pen a few quick notes before diving into a longer-form review later this fall. This is a First Look, however, not a full review, so more on that later.
The Sunliner is similar in geometry to the Prospector, Tumbleweed’s Rohloff-specific touring bike, but is designed for a 1x chain drivetrain. Another noticeable difference between the Sunliner and Prospector is the latter has a much more compact frame design overall and has massive tire clearance. Read all about the Prospector in Ryan Wilson’s in-depth review.
I’m riding the size XL with an 81 cm saddle height shown here as a 6’2″ human with long legs
Run the Numbers
Geometrically speaking, what differentiates the Sunliner from the Stargazer is linked to the frame’s reach, since it has a flat-bar riding position. Generally, a flat-bar bike has a slightly longer top tube to compensate for the rider’s change in fit extension when riding flat bars versus drop bars.
The Sunliner has a larger frame bag space across all sizes and I can squeeze this BXB L-XL Better Half frame bag along with two 26 oz bottles. It’s massive!
As such, the Sunliner’s top tube grew across all sizes, as did the reach, and on the production bikes – I’m riding a pre-production sample here – the chainstays lengthened to give more tire clearance and to allow for easier framebag mounting. Touring bikes often have longer chainstays or rear-centers, anyway, which makes the bike ride more planted when loaded down. Adding to the additional 6 mm chainstay length, the bottom bracket dropped 1.5 mm too. And the stack varies across all sizes due to the longer effective top tube.
Did I mention this new color, dubbed Rhubarb, is something else? Wow!
That’s All (For Now) Folks!
I’ve got some plans for the Sunliner as the summer wanes and the fall settles in here in the Southern Rockies filled with lots of singletrack touring and shredding! The Sunliner is in stock and shipping today from Tumbleweed Bicycle Co.
I wanted to thank Daniel from Tumbleweed for loaning me his personal bike for this review. If you’d like me to focus on anything in particular in the full-length review, let me know in the comments!
