Recumbent (RaptoBike) weight analysis

There’s been some discussion over on the Nazca Fuego review about the weight of that bike (particularly, how extras contribute to lifting the real over the ‘quoted’ weight). This prompted me to dig out this old data on my Raptobike lowracer…

A couple of years ago we had quite a harsh winter and I decided to completely strip the RaptoBike lowracer and clean everything up. I took the opportunity to weigh everything for my own amusement, and the interest of third parties.

rapto

The standard disclaimer applies: I don’t think a handful of grams (or a couple of kilos) makes much of a difference seen in light of the overall rider+bike weight but, ultimately, weight is what sells bikes as it’s much easier to quantify than stiffness or aerodynamics.

The total bike weight was 14.6kg (32.2lbs). This isn’t including pedals, which aren’t normally weighed for upright bikes either (but add another few hundred grams).

I’ve given the weight of the parts in kilos because I struggle to do base 12 mathematics in my head:

Structure

3.120 Frame (inc headset)
0.086 Small idler
0.165 Large idler
0.080 Idler cover
0.860 Fork (inc. Star nut & cap)
0.650 Boom (uncut, with mech post)
========================
4.961 kg

Seating

0.580 VeloKraft carbon seat
0.440 Ventisit comfort pad
0.325 seat mounting hardware, bolts etc.
========================
1.345 kg

Drivetrain

0.570 cranks
0.280 BB
0.300 Rear mech
0.185 Front mech
0.350 Cassette
0.180 52t ring
0.092 39t ring
0.515 standard chain (not lightweight)
===============
3.300 kg

Braking

0.300 Elixir hydraulic front disc (including lever & line)
0.310 BB5 mechanical rear disc (including lever & cable)
0.115 rotor
0.115 rotor
============
0.840 kg

Steering / controls

0.211 Stem
0.223 Bar
0.107 Mirror
0.050 grips
0.100 gripshift
0.100 gripshift
=============
0.791 kg

Wheels

remembering that the RaptoBike is a fwd bike, so the hubs are reversed…

0.995 front wheel
- 380g "rear" hub
- 060g skewer
- 555g rim & spokes
1.205 rear wheel
- 190g "front" hub
- 065g skewer
- 950g rim and spokes
0.230 Kojak 406
0.600 Marathon 26"
0.095 tube 406
0.130 tube 26"
0.185 mudguard
=================
3.440 kg

Easily shed weight

Without spending much, it would be possible to considerably reduce the weight of the stock bike. You can drop a kilo just by:

  • No mudguard – save 185g
  • Lightweight tubes – save ~75g
  • Fit a road-style 700C front wheel to the rear – save ~300g
  • Swap Marathon for light 700C slick – 375g saving with a GP4000s
  • Switch from Ventisit to foam pad – save at least 200g

Wheel-wise, 3.4kg is a huge amount (you can buy road wheels which come in at less than half that much) so you’d certainly be able to do something with the front too.

Then you could look at switching to rim brakes (small saving in weight in exchange for worse braking), and clothing choices. Switching from heavy walkable shoes to rigid plastic-based road shoes will save a lot of weight – rotating weight at that :-)

Notes

  1. Another rider with a boom cut to length (and no mech post) reports a boom weight of 370g, or a significant saving of 280g (caveat emptor)

3 Comments

  1. HI,

    interesting to read, but in my case, I think it would be more productive to lose 7 kg of of my bodyweight and leave the Lowracer just as it is 😉

  2. Matěj Novotný

    I have got same wheel sizes on my bike and they are 400 g lighter but still very durable. They are built by czech Remerx to my order and was not expensive. I have got rims designed for disc brakes, MTB rims. And 2 mm spokes. By using road rims and butted spokes you can save some grams.

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