DIY Lightweight Carbon Spider Power Meter Crankset: Lighter & (Potentially) Cheaper than a Magene P515 TEO?

Build a lighter modular spider-based power meter crankset using a carbon carnkset + a spider powermeter instead of buying a heavier spider powermeter crankset combo.

This guide covers the motivation, crankset and spider options, weights, cost comparisons, assembly steps, and pros/cons vs. an all‑in‑one solution.

🚀 TL;DR
✅ Goal: 384–464 g crank + spider vs. ~625 g integrated budget set
✅ Standard interface: Easton/Raceface Cinch enables future crank upgrades
✅ Cost window: ≈ $525–1345 (arms + spider) depending on crank tier
✅ Serviceable: No proprietary spindle or arm format
⚠️ Effort: Sourcing parts & specific lockring tool needed

Motivation

Budget integrated crankset power meters (e.g. Magene P515 PES) are inexpensive but heavy and locked to a single arm/spider format. Shimano road cranks are also comparatively heavy.

A bunch of lighter carbon crank options exist, but ship without a power meter.

The aim: combine a lightweight carbon crankset with a modular spider power meter for a lighter, servicable and upgradable system.

Crankset Overview

The majority of Chinese carbon cranks now use the Easton/Raceface Cinch direct mount interface. That lets you attach a Cinch-compatible spider power meter or spider interface directly.

Spindle compatibility note: Choose 24mm for Shimano BB compatibility, or 29mm (DUB) for SRAM bottom brackets if you want to keep your existing bottom bracket.

How to Choose Your Crankset

The right crankset depends on your priorities, budget and existing bottom bracket. Here’s a practical decision framework:

• Budget-focused (~$240-255): The Rockbros DUB crankset offer the most lightweight budget carbon crankset option on the market, if you don’t mind the prominent branding. The 24mm crankset variant comes with a slight weight penality (365g vs 325g for DUB).
• Balanced approach (~$415-505): The EILEE X310 is even more lightweight than the the Rockbros Option, with much more decent branding. If you want to stick with a 24mm Bottom Bracket or don’t like the excessive branding of the Rockbros Option, this is the way to go, as both variants come in at just 310g.
• Weight-obsessed (~$920): The EILEE X-Novanta is the only sub-300g option available on the market. Coming in at just 285g, this is the ultimate weight-weenie option. Due to its carbon spindle it is only compatible with 28.99mm DUB or 30mm bottom brackets however.

Specifications

Complete technical specifications for all Cinch-compatible crankset options, combining official EILEE spec sheets with available Rockbros data.

Model	Spindle & Material	Lengths	Q-Factor	Chainline	Weight	Price
Rockbros DUB	28.99 mm DUB (aluminum)	162.5–175 mm (2.5mm increments)	148 mm	44.5 mm	325 g	$240
Rockbros 24mm	24 mm (titanium alloy)	162.5–175 mm (2.5mm increments)	148 mm	44.5 mm	365 g	$255
EILEE X310-DUB	28.99 mm DUB Alu	155, 160, 165, 170, 172.5, 175 mm	149 mm	44.5 mm	310 g	$415
EILEE X310-24mm	24 mm Titanium	155, 160, 165, 170, 172.5, 175 mm	151.5 mm	44.5 mm	310 g	$505
EILEE X-Novanta	28 mm Carbon (adapts to 28.99 mm DUB or 30 mm)	155, 160, 165, 170, 172.5, 175 mm	149 mm	44.5 mm	285 g	$920

Positioning guide: Rockbros delivers the lowest entry cost with two spindle options—DUB for SRAM systems or 24mm for Shimano BB compatibility. The new 24mm variant adds titanium axle and slightly higher price but maintains budget positioning, it does however carry at 40g weight penalty over the DUB variant. The EILEE X310 variants offers a lower weight of just 310g with no weight penalty between the DUB and 24mm spindle options. The X-Novanta targets weight-obsessed builds where every gram justifies significant cost, without a 24mm spindle option however.

Practical recommendations:

• Price performance: The Rockbros DUB Crankset offers the best price performance, coming in at just 325g. If you are using Shimano however, you will need a new bottom bracket.
• Bike stylists: If you care about how your bike looks, either of the EILEE X310 cranksets are an excellent choice.
• Shimano BB users: 24mm spindles work with most BB standards; Rockbros 24mm ($255) or X310-24mm ($505) depending on budget. X310 offers same weight as DUB version, while Rockbros 24mm version adds 50g
• Weight weenies: X-Novanta ($920) only makes sense if targeting sub-6kg total bike weight and cost isn’t a primary concern

Key Observations:

• Weight progression: X-Novanta (285g) < X310 (310g) < Rockbros DUB (325g) < Rockbros 24mm (365g)
• Length options: EILEE offers shorter lengths (155mm minimum) vs. Rockbros (162.5mm minimum); both provide 6 size options with different increments
• Chainline consistency: All models use standard 44.5mm chainline for broad compatibility
• Price-to-weight ratio: Rockbros delivers budget entry; EILEE offers the most lightweight 24mm spindle option; X-Novanta targets absolute weight minimization

Spider Power Meter Options

When chosing a suitable spider powermeter for the Easton/Raceface Cinch direct mount interface, there are two popular choices: Sigeyi AXO and XCadey XPOWER Spider Powermeters. Both powermeters are available as 110BCD 4 and 5-bolt variants, depending on your choice of chainrings. If you want to use the latest Shimano Chainrings, you will want to go with the 110BCD 4-bolt variant.

To choose the right powermeter for your needs, I recommend taking a look at the table below:

Powermeter	Accuracy	Weight	Battery Life	Working Temperature	Charging Connector	Price
Sigeyi AXO 110BCD	+/- 1.0%	99 g	300h	-20 – 50°C	Magnetic Flat (compatbile with Magene)	$425
XCadey XPOWER 110BCD	+/- 1.5%	110 g	150h	-10 – 50°C	Proprietary round connector	$285

The comparison shows, that the Sigeyi AXO is superior to the XCadey XPOWER Spider Powermeter in every category, except price. The main advantages, are the higher claimed accuary of 1.0% vs 1.5%, lower weight of 99g vs 110g and double the battery life at 300h vs 150h. Furthermore the working temperature can be as low as -20 °C, whilst the XCadey is only rated until -10 °C. At last if you are an existing Magene Spider Powermeter user, the Sigeyi AXO has the same charging connector, so you won’t have to get used to using a different charging cable.

Recommendation: Sigeyi AXO for proven reliability, superior accuracy and battery life.

Budget alternative: XCadey XPOWER if you don’t mind recharging more regularly and have another reliable powermeter to calibrate against.

Weight & Cost Comparison

Setup	Crank	Spider	Total Weight	Total Price	Comment
Budget DUB	Rockbros DUB 325 g	Sigeyi 99 g	~424 g	$665	Best $ per gram saved
Budget 24mm	Rockbros 24mm 365 g	Sigeyi 99 g	~464 g	$680	Shimano BB compatible
Balanced	EILEE X310 310 g	Sigeyi 99 g	~409 g	$840	Verified specs, moderate premium
Ultra Light	EILEE X-Novanta 285 g	Sigeyi 99 g	~384 g	$1345	Lightest, significant cost
Budget DUB Alternative	Rockbros DUB 325 g	XCadey 110 g	~435 g	$525	Lowest cost entry
Reference	Magene P515 TEO (DUB)	(integrated ~100 g)	~425 g	$640	Heavier, but plug-and-play

The modular DIY Budget DUB option with the Sigeyi AXO PM comes in at the same weight as the Magene P515 TEO option, whilst offering a non-proprietary spider interface, which enables future powermeter and crankset upgrades. Price-wise there is no significant difference. When picking the Budget DUB Alternative with the cheaper XCadey XPOWER Powermeter, you can save significantly over the Magene P515 TEO Crankset, whilst just adding 10g of extra weight.

The other options are significantly more expensive, whilst offering the option to keep a Shimano bottom bracket or save even more weight at a higher cost.

Assembly Overview (Budget DUB)

Attaching the Powermeter to the Crankarm

Installing the Chainrings

Mounting the Crankset

The last step is to mount the crankset onto the bike.

Warning: Before doing so make sure you have the appropriate bottom bracket with the right amount of spacers installed on your bike.

The installation steps will vary depending on your crankset and spindle type, the following steps are for the Rockbros DUB Crankset.

For this you will need the following tools:

• Grease
• Torque Wrench
• 8mm Socket
• Allen Key Set

Grease the non-drive side axle before sliding it into the bottom bracket.

Now attach the drive-side with the Spider Powermeter and torque it down to specification using the torque wrench and 8mm Socket.

Finally use the adjuster on the non-drive side to adjust the bearing play, loosen the adjuster using the appropriate allen key before adjusting it.

Common Questions & Considerations

Bottom Bracket Compatibility

Q: Which BB standard for my frame?
24 mm spindles work with BSA/ITA threaded (adapter cups), BB86/90/92 press-fit. 29 mm (DUB) requires DUB-compatible BBs. 30 mm needs BB30, PF30, or appropriate adapters. Check your frame specifications before ordering.

Chainring Compatibility

Q: Can I use my existing Shimano chainrings?
110 BCD 4-bolt chainrings (Shimano or aftermarket) work directly. For other standards you need different rings.

Upgrade Path

Q: Can I reuse the spider with different cranks later?
Yes—this is the key advantage. The Sigeyi AXO spider works with any Cinch-compatible arms, allowing future upgrades without buying a complete new power meter system.

DIY Crankset vs. P515 TEO

Recommendation & Conclusion

If absolute budget is priority, an integrated set (Magene P515 PES) is fine. If you value weight, modularity, and future-proofing, a Cinch + spider build wins. My personal sweet spot: Sigeyi AXO + Rockbros DUB for price-performance, reliability and weight.

In short: DIY shines for weight-focused, tech‑savvy riders; integrated cranksets remain the easy plug‑and‑play path.