Understanding your mountain bike’s hub specifications is the key to ensuring structural alignment, precise disc brake positioning, and secure wheel retention. These dimensions—specifically Over-Locknut Dimension (O.L.D.), axle diameter, and spacing standards like Boost—define how your wheels interface with your frame and fork. Knowing how to decode these measurements prevents you from purchasing incompatible components that will not fit your bicycle.
In the Philippines, where rugged trails in locations like San Mateo or Nuvali subject your bike to intense vibrations, selecting the correct hub specification is critical for safety and performance. High humidity and muddy trail conditions mean your hub interfaces must be precisely aligned to prevent premature wear on bearings and frame dropouts.
Decoding Hub Spacing and Over-Locknut Dimensions (O.L.D.)
Over-Locknut Dimension, commonly abbreviated as O.L.D., is the foundational measurement of any bicycle hub. It refers specifically to the distance between the outer clamping surfaces of the hub’s end caps or locknuts—the exact points where the hub contacts the inside of the fork or frame dropouts. A common mistake is confusing O.L.D. with the total length of the axle itself, which is always longer to allow for insertion or clamping.
Products mentioned in this guide
28 Lazada user ratings
Stylish color options to choose from, Efficient seal bearing for smooth riding experience, Versatile hub suitable for various terrains, 🔨Dur…Read full reviewShow less
Stylish color options to choose from, Efficient seal bearing for smooth riding experience, Versatile hub suitable for various terrains, 🔨Durability: good as quality material 🔌Compatibility: excellent 🛠️Ease of Installation: satisfaction new look
mabilis naship at nadeliver tama din ang item at walang damageDurable and lightweight design, Easy and quick installation process,
Efficient seal bearing for smooth riding experience, Perfect hub choice for mountain biking enthusiasts,
good quality no damage and correct item. ive bought 4x from this shop i think 2 rear hubs and 2 cranks
1,162 Lazada user ratings
pinakabahan ako ne seller wala kasing reply sa mga chat ko nag baka sakali akung hindi tama ang item na ma deliver,,pero goods na goods wala…Read full reviewShow less
pinakabahan ako ne seller wala kasing reply sa mga chat ko nag baka sakali akung hindi tama ang item na ma deliver,,pero goods na goods walang damage at tama lahat ng item based sa order ko,Maraming salamat po,,pero sana mag reply ka naman eh...
Great value for the price, Sleek and stylish design, Suitable for various terrains, Quality:5 Appearance:5 Performance:5
thank you seller at rider,ganda ng item tama ang order ko,legit ang store nyo,order ulit ako kpg ngkabudget.salamat
solid budget meal tunog mayaman matagal nga lang dumating pero sulit naman ang paghihintay overall solid
solid ang ganda ang lakas nang tunog sulit ang pag aantay mo ganda nang item thank you seller
700 Lazada user ratings
🔨Durability:8/10 hindi pa naikakabit 🔌Compatibility:9/10 mukhang fit sa bike ko pero hindi ko pa nailalagay sa bike ko. 🛠️Ease of Installatio…Read full reviewShow less
🔨Durability:8/10 hindi pa naikakabit 🔌Compatibility:9/10 mukhang fit sa bike ko pero hindi ko pa nailalagay sa bike ko. 🛠️Ease of Installation:10/10 madaling makabit dahil QR Versatile hub for different terrains, Durable and long-lasting, Efficient power transfer for better performance, sobrang ganda niya sa personal. shaka ang ganda ng tunog niya para sakin. matinis yung sounds niya. may kabigatan siya dahil sa bearing dahil apat ito. alloy na siya at maganda pagka kulay niya. sana tumagal. order na rin kayo.
Ok sya maayus naman walang kulang at saktu nadin ang tunog At maraming salamat kay kuya raider na napaka Bait nya kaya 5 star sayu boss
Dumating kahapon, di pa natratry eh kaya i pa5star ko nalang hehe thanks po sobrang tagal ngalang dumating an tagal ng lex ph
The grip is solid Haven't installed it yet, but it feels quite complete and the sound is also okay.
160 Lazada user ratings
Have not installed it yet on my son's MTB. The price is reasonable. Overall it seems durable and easy to install. The shop / seller is legit…Read full reviewShow less
Have not installed it yet on my son's MTB. The price is reasonable. Overall it seems durable and easy to install. The shop / seller is legitimate. The shipping is very fast and secured. We have bought our other MTB needs /parts here. And the performance is at par with other brands.
🔨Durability:mukhang matibay naman.. solid ang materials. 🔌Compatibility:midyo manipis lang Yung spoke compare sa stock, pati nipples maliit.…Read full reviewShow less
🔨Durability:mukhang matibay naman.. solid ang materials. 🔌Compatibility:midyo manipis lang Yung spoke compare sa stock, pati nipples maliit. Hindi sya pwede sa rim ng bike ko na stock rim. pero legit naman.. salamat parin
nice packaging, good quality, all items received, with freebies, thank you seller 🔨Durability:10/10 🔌Compatibility:10/10 🛠️Ease of Installati…Read full reviewShow less
nice packaging, good quality, all items received, with freebies, thank you seller 🔨Durability:10/10 🔌Compatibility:10/10 🛠️Ease of Installation:10/10
Easy installation and maintenance, Versatile compatibility with various speeds, Alast, My MTB got upgraded for how many years of hardworking…Read full reviewShow less
Easy installation and maintenance, Versatile compatibility with various speeds, Alast, My MTB got upgraded for how many years of hardworking etc..
maganda at mukhang matibayExcellent value for the price,
337 Lazada user ratings
🔨Durability:durable hubs for long usage purposes 🔌Compatibility:compatible to almost all rims 🛠️Ease of Installation:easy to install and func…Read full reviewShow less
🔨Durability:durable hubs for long usage purposes 🔌Compatibility:compatible to almost all rims 🛠️Ease of Installation:easy to install and functions well Six pawl hub for smooth engagement,
goods sya may Libreng TA cup tas manilisSuitable for front and rear hubs, High-performance MTB hub option, Enhanced handling and stability,
🔨Durability:10 🔌Compatibility:10 🛠️Ease of Installation:10 the sound is nice . perfect and it last long
this is gift for my grand mother that passed on the exam during they're quiz on lolas plays Soo yeah
179 Lazada user ratings
6 bearing design for smooth rotation, Quick release QR system included, 32/36 hole options available, Suitable for MTB and hybrid bikes, Dur…Read full reviewShow less
6 bearing design for smooth rotation, Quick release QR system included, 32/36 hole options available, Suitable for MTB and hybrid bikes, Durable aluminium alloy material,
DurableSuitable for MTB and hybrid bikes, aluminium alloy material, Quick release QR system included, Quick release QR system included,
2 thumbs up. napakaganda ng tanke hub 240 na ito. smooth wheeling and the sounds grabe grabe lakas. makayaman.
6 bearing design for smooth rotation, Quick release QR system included, Suitable for MTB and hybrid bikes,
🛠️Ease of Installation:Quick release QR system included, 🔌Compatibility:32/36 hole options available,
18 Lazada user ratings
ang ganda ng itims,,lakas Ng tunog,,dika lugi d2 mga ka trops,,,,sulit na sulit ang Pera nyo,, maraming maraming salamat po Lazada seller at…Read full reviewShow less
ang ganda ng itims,,lakas Ng tunog,,dika lugi d2 mga ka trops,,,,sulit na sulit ang Pera nyo,, maraming maraming salamat po Lazada seller at Kay ate n nag deliver kahit mainit,, dahil jan ay 💯⭐⭐⭐⭐✨ po kau skin lahat,,
Goods nman ang performnce ng item maganda. sana lang naka box ung item hndi kasi effective ang bubble wrap may mga gasgas. Pero overall okay…Read full reviewShow less
Goods nman ang performnce ng item maganda. sana lang naka box ung item hndi kasi effective ang bubble wrap may mga gasgas. Pero overall okay.
Perfect for mountain biking,
Bakit iisang lang po un
Prices are valid at publication and may change. Please refer to the product page for the latest price.
For front hubs, common O.L.D. measurements include 100mm for older or cross-country setups and 110mm for modern trail and enduro forks. Rear hubs feature a wider variety of spacing standards, typically ranging from older 135mm quick-release setups to 142mm, 148mm (Boost), and even 157mm (Super Boost) for downhill or heavy-duty trail frames.
Because bicycle frames and forks are engineered with rigid tolerances, your hub’s O.L.D. must match your frame and fork dropouts exactly. Attempting to force a wider hub into a narrower frame, or clamping down a frame onto a hub that is too narrow, places severe structural stress on the frame material. This misalignment can lead to frame damage, poor shifting, and compromised disc brake caliper alignment.
Thru-Axle vs. Quick Release (QR) Axle Standards
The method used to secure your wheel to your bike generally falls into one of two categories: quick-release (QR) skewers or thru-axles. Quick-release systems rely on a thin 5mm skewer that passes through a hollow hub axle, using a cam-lever clamping mechanism to pull the frame dropouts tightly against the hub end caps. While convenient for tool-free wheel removal, QR systems do not offer the same structural rigidity as modern alternatives under heavy trail loads.
In contrast, a thru-axle is a thick, solid, or hollow pin that slides directly through closed holes in the frame or fork dropouts and threads directly into the opposite side. This design makes the axle a load-bearing structural member of the frame, significantly reducing lateral flex during hard cornering or technical descents.
When replacing a thru-axle, you must match three distinct measurements: the overall shaft length, the outer diameter, and the thread pitch. The diameter is typically 15mm or 20mm for front forks, and 12mm for rear dropouts. The overall length must match the outer width of your specific frame or fork dropouts, which varies even among bikes with the same hub spacing due to differing dropout thicknesses.
The most critical and easily overlooked specification is the thread pitch, which is the distance between individual thread ridges (typically 1.0mm, 1.5mm, or 1.75mm). Using an axle with the wrong thread pitch will permanently ruin the threads inside your fork or frame. Always verify the manufacturer’s exact specifications or inspect the markings on your original axle before installing a replacement.
Boost vs. Non-Boost Spacing Explained
As mountain bikes transitioned to larger 29-inch and 27.5-inch wheels, riders and manufacturers faced a challenge with wheel flex. This led to the introduction of the “Boost” standard, which increased the standard hub widths to provide a more stable platform. While non-Boost front hubs typically measure 100mm wide and rear hubs measure 142mm, Boost standards expand these dimensions to 110mm in the front and 148mm in the rear.
The primary mechanical benefit of Boost spacing lies in the wider placement of the hub flanges, which are the metal rings where the spokes attach. By pushing these flanges further outward, the bracing angle of the spokes is increased, creating a wider, more stable triangular structure. This wider bracing angle results in a stiffer wheel, reducing lateral flex without requiring heavier rims or spokes.
Additionally, the wider rear spacing pushes the chainline outward by 3mm. This adjustment allows frame designers to widen the chainstays, providing extra clearance for wider, high-traction tires and shorter chainstays for more agile handling.
Because of these physical changes, Boost and non-Boost components are generally not cross-compatible. A non-Boost wheel will not fit securely in a Boost frame without specialized, manufacturer-approved spacer kits that offset both the disc brake rotor and the hub end caps. Conversely, a Boost hub cannot be modified to fit into a narrower, non-Boost frame or fork because the physical hub shell is too wide.
How to Verify Hub and Frame Compatibility
Before purchasing a new hub or wheelset, taking precise physical measurements of your current setup is a reliable way to ensure compatibility. A digital caliper is a practical tool for this task, allowing you to measure the internal distance between your frame’s rear dropouts or your fork’s lower legs to confirm the O.L.D. You can also measure the outer diameter of your existing axle and its overall length to the nearest millimeter.
Once you have gathered these physical dimensions, cross-reference them with the official geometry and specification charts provided by your bike frame and fork manufacturers. Many brands print these specifications directly on the frame or fork legs, often near the dropouts or on the underside of the bottom bracket shell.
If you encounter ambiguous measurements, find that your existing dropouts are worn or damaged, or are considering aftermarket conversion adapters, it is advisable to stop and consult a professional bike mechanic. A qualified local bike shop in the Philippines can use specialized thread gauges and alignment tools to verify your frame’s integrity and ensure your new hub setup is safe to ride.
Frequently Asked Questions (FAQ)
Can I convert a non-Boost hub to fit a Boost frame?
Yes, some non-Boost hubs can be converted using aftermarket spacer kits, but compatibility is highly dependent on the hub brand and model. These kits typically include wider end caps and a spacer to push the disc brake rotor outward so it aligns with the brake caliper. However, you must verify that your chainline remains functional and that the conversion kit is officially approved by the hub manufacturer to avoid compromising structural safety.
Does a larger thru-axle diameter always mean a stronger wheel?
While a larger thru-axle diameter increases the stiffness and strength of the interface between the wheel and the frame or fork, it does not automatically make the wheel itself stronger. The overall strength of the wheel depends on the rim material, spoke count, spoke tension, and hub flange design. Furthermore, you cannot upgrade to a larger axle diameter because the maximum size is strictly dictated by the pre-existing holes in your frame and fork dropouts.
How do I find the correct thread pitch for my thru-axle?
The recommended way to find your thru-axle’s thread pitch is to check the manufacturer’s official documentation or look for laser-etched specifications on the shaft of your original axle. If the markings have worn off, do not guess the pitch, as forcing an incorrect axle will strip the threads of your frame or fork. Instead, take your original axle to a qualified local bike shop in the Philippines to have it measured with a professional thread pitch gauge.
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