Bikes of Bentang Jawa
Eight decisions, ridden 1,500 km across Java — this is how 30 bikes answered them
Pick a component to see how the field splits.
Rubber
Tyre width is on record for 30 of the 30 bikes in the 2025 field.
Java's 1,500 km is tarmac, broken tarmac, and the occasional excuse for a road. Tyre choice is where riders place their bet — and the field bets narrow.
Width
Most of the field runs 30–32 mm
68% of the widths given in millimetres
19 of 30 documented
| Category | Value |
|---|---|
| Verdict | Most of the field runs 30–32 mm |
| Figure | 68% of the widths given in millimetres |
| Bikes documented | 19 |
| Bikes counted | 30 |
| Share documented | 63% |
Tyre width
30–34 mm is the busiest bucket, on 20 of 30 bikes
Bikes per width bucket, 2025.
| Category | Value |
|---|---|
| 25-29mm | 4 bikes (13%) |
| 30-34mm | 20 bikes (67%) |
| 35-39mm | 3 bikes (10%) |
| 40-44mm | 2 bikes (7%) |
| 45-50mm | 1 bikes (3%) |
Tyre make
Not documented for 2025. None of the 30 bikes on record for this edition names one.
The Frames
Frame type is on record for 29 of the 30 bikes in the 2025 field; what the frame is made of, for 29.
Road bike or gravel bike? Across Java the honest answer is "both, and it depends on the potholes" — but road bikes have the majority here.
Frame type
Road bikes lead the field
59% road to 41% gravel
29 of 30 documented
| Category | Value |
|---|---|
| Verdict | Road bikes lead the field |
| Figure | 59% road to 41% gravel |
| Bikes documented | 29 |
| Bikes counted | 30 |
| Share documented | 97% |
Road versus gravel
Road and gravel split 59% to 41%
Frame type, 2025.
| Category | Value |
|---|---|
| road | 17 bikes (59%) |
| gravel | 12 bikes (41%) |
Frame material
Carbon frames make up 69% of the bikes that name a material
Carbon dominates, but titanium and steel are both here.
| Category | Value |
|---|---|
| Carbon | 20 bikes (69%) |
| Aluminium | 5 bikes (17%) |
| Titanium | 3 bikes (10%) |
| Steel | 1 bikes (3%) |
The badge on the down tube
A make is on record for 5 of the 30 bikes in the 2025 field, across 5 different names.
Which badge is on the down tube is the one decision on a bike a rider can copy outright. What this section can say about it is decided entirely by the count above — how many of this edition's bikes named a make at all.
Bike make
Recorded for 5 of 30 bikes — under half the field. Read what follows as a hint, not a verdict.
Drivetrain
Chainring layout is on record for 17 of the 30 bikes in the 2025 field, and not one of them names its groupset.
16,000 metres of climbing is the whole argument. Gearing here is not about top speed — it is about still being able to turn the pedals on day five.
Chainrings
2× runs the field
82% of documented drivetrains
17 of 30 documented
| Category | Value |
|---|---|
| Verdict | 2× runs the field |
| Figure | 82% of documented drivetrains |
| Bikes documented | 17 |
| Bikes counted | 30 |
| Share documented | 57% |
One ring or two
2x setups run 82% of drivetrains
| Category | Value |
|---|---|
| 1x | 3 bikes (18%) |
| 2x | 14 bikes (82%) |
Groupset
Not documented for 2025. None of the 30 bikes on record for this edition names one.
Mechanical or electronic
Mechanical shifting runs on 54% of the bikes that record it
Wires and batteries, six days from a plug socket.
| Category | Value |
|---|---|
| electronic | 13 bikes (46%) |
| mechanical | 15 bikes (54%) |
Wheels
Not documented for 2025. None of the 30 bikes on record for this edition names one.
Easiest gear
0.71 is the lowest in the field
30t ring on a 42t cog
16 of 30 documented
| Category | Value |
|---|---|
| Verdict | 0.71 is the lowest in the field |
| Figure | 30t ring on a 42t cog |
| Bikes documented | 16 |
| Bikes counted | 30 |
| Share documented | 53% |
Hardest low gear
1.00 is the highest anyone risked
34t ring on a 34t cog
16 of 30 documented
| Category | Value |
|---|---|
| Verdict | 1.00 is the highest anyone risked |
| Figure | 34t ring on a 34t cog |
| Bikes documented | 16 |
| Bikes counted | 30 |
| Share documented | 53% |
Lowest gear, easiest first
The easiest gear in the field is 0.71 — a 30t ring on a 42t cog
Smallest chainring divided by biggest sprocket. Lower is easier. Bars scale to the hardest gear in this edition (1.00).
- Cervelo Aspero 30t × 42t 0.71
- Cap 164 — unlisted bike 31t × 42t 0.74
- Specialized Diverge E5 40t × 51t 0.78
- Cap 114 — unlisted bike 34t × 42t 0.81
- Cap 121 — unlisted bike 34t × 42t 0.81
- Cap 133 — unlisted bike 33t × 40t 0.82
- Cannondale Topstone Carbon 30t × 36t 0.83
- Cap 102 — unlisted bike 38t × 44t 0.86
- Cap 172 — unlisted bike 40t × 46t 0.87
- Cap 53 — unlisted bike 34t × 36t 0.94
- Cap 96 — unlisted bike 34t × 36t 0.94
- Cap 109 — unlisted bike 35t × 36t 0.97
Show all 16 bikes
- Cap 179 — unlisted bike 35t × 36t 0.97
- Cap 101 — unlisted bike 34t × 34t 1.00
- Cap 103 — unlisted bike 36t × 36t 1.00
- Cap 143 — unlisted bike 34t × 34t 1.00
| Category | Value |
|---|---|
| Cervelo Aspero | 30t × 42t = 0.71 |
| Cap 164 — unlisted bike | 31t × 42t = 0.74 |
| Specialized Diverge E5 | 40t × 51t = 0.78 |
| Cap 114 — unlisted bike | 34t × 42t = 0.81 |
| Cap 121 — unlisted bike | 34t × 42t = 0.81 |
| Cap 133 — unlisted bike | 33t × 40t = 0.82 |
| Cannondale Topstone Carbon | 30t × 36t = 0.83 |
| Cap 102 — unlisted bike | 38t × 44t = 0.86 |
| Cap 172 — unlisted bike | 40t × 46t = 0.87 |
| Cap 53 — unlisted bike | 34t × 36t = 0.94 |
| Cap 96 — unlisted bike | 34t × 36t = 0.94 |
| Cap 109 — unlisted bike | 35t × 36t = 0.97 |
| Cap 179 — unlisted bike | 35t × 36t = 0.97 |
| Cap 101 — unlisted bike | 34t × 34t = 1.00 |
| Cap 103 — unlisted bike | 36t × 36t = 1.00 |
| Cap 143 — unlisted bike | 34t × 34t = 1.00 |
Mullet builds
4
bikes ran a mullet — road shifters driving an off-road derailleur and cassette (GRX, Deore, XT, XPLR). It is the cheapest way to buy a climbing gear a road groupset will not give you.
30 of 30 documented
Carrying it all
At least one bag is on record for 28 of the 30 bikes in the 2025 field.
This is where Bentang Jawa stops looking like every other ultra. Tailfin and Apidura are here, of course — but so are Bandung and Jakarta workshops stitching frame bags to order, one rider at a time.
Indonesian-made bags
Indonesian makers are on 38% of bagged bikes
8 local makers, 14 bikes
28 of 30 documented
| Category | Value |
|---|---|
| Verdict | Indonesian makers are on 38% of bagged bikes |
| Figure | 8 local makers, 14 bikes |
| Bikes documented | 28 |
| Bikes counted | 30 |
| Share documented | 93% |
Indonesian makers on the start line
Every local brand in the dataset, and how many bikes carried it.
Satset
Carried on 6 bikes in the field
- bags
URBNCASE
Carried on 5 bikes in the field
- bags
Wahaw Adventure
Carried on 2 bikes in the field
- bags
Boogie
Carried on 1 bike in the field
- bags
Eiger Adventure
Carried on 1 bike in the field
- bags
Green Forest
Carried on 1 bike in the field
- hydration
GXID
Carried on 1 bike in the field
- bags
Sekayuh
Carried on 1 bike in the field
- bags
Local versus international
38% of bag-carrying bikes used an Indonesian maker
Counted per bike. A bike running both is counted in both columns.
| Category | Value |
|---|---|
| Indonesian makers | 14 bikes (38%) |
| International brands | 23 bikes (62%) |
Bag brands
Apidura is the most common bag brand, on 50% of bikes with bags recorded
Bikes per brand.
+5 more not shown
| Category | Value |
|---|---|
| Apidura | 14 bikes |
| Brooks England | 6 bikes |
| Satset | 6 bikes |
| Bontrager | 5 bikes |
| URBNCASE | 5 bikes |
| Rhinowalk | 4 bikes |
| Tailfin | 4 bikes |
| Topeak | 3 bikes |
| FARA | 2 bikes |
| Wahaw Adventure | 2 bikes |
| Boogie | 1 bikes |
| Cycology | 1 bikes |
| Eiger Adventure | 1 bikes |
| GXID | 1 bikes |
| Rapha | 1 bikes |
| Sekayuh | 1 bikes |
| Ulac | 1 bikes |
| More | +5 more not shown in the chart above |
Cockpit & contact points — what we know least
In the 2025 field, aero bars are on record for 30 of 30 bikes. Not one of them names a saddle or a pedal.
Six days on a bike means the three places you touch it matter more than the frame does. It is also the part of a bike a caption describes least completely: the frame and the tyres get named almost every time, the saddle and pedals far less often.
Aero bars
Just over half ride on their elbows
53% ran aero or rest bars
30 of 30 documented
| Category | Value |
|---|---|
| Verdict | Just over half ride on their elbows |
| Figure | 53% ran aero or rest bars |
| Bikes documented | 30 |
| Bikes counted | 30 |
| Share documented | 100% |
Aero and rest bars
53% of documented cockpits carry aero or rest bars
Once a time-trial affectation, now a place to rest your elbows.
| Category | Value |
|---|---|
| aero bars | 16 bikes |
| no aero bars | 14 bikes |
Bar setup
Not documented for 2025. None of the 30 bikes on record for this edition names one.
Saddles
Not documented for 2025. None of the 30 bikes on record for this edition names one.
Pedals
Not documented for 2025. None of the 30 bikes on record for this edition names one.
The road these bikes crossed
West to east across Java, self-navigated and self-supported, solo or in pairs — this is what the field rode to close the distance.
Distance
1,500 kilometres
west → east
Climbing
16,000 metres
on the organiser’s profile
Cutoff
156 hours
≈ 6.5 days riding
Support
0 vehicles
fully self-supported
Line traced from bob aria bharuna's ride on RideWithGPS — a GPS-measured 1,502 km with 17,365 m of climbing. That's a separate, equally valid measurement from the race facts above, not a correction to them; those are the organiser's, from bentangjawa.cc.