How to build a custom lightweight bike

Today we have a special guest blog post from Lukas, one of Litebike's co-founders, on a custom lightweight bike he built.

Choosing the right frame

Late last summer I decided to take on a bike build of my own and see what I could put together on a budget. I wanted to build a bike with a healthy balance between weight and aerodynamics that could perform as well on mountainous climbs as on the flat open road.

Starting with the frame and keeping it on budget I went with a Velobuild VB-R-068, which is an aero-type rim brake frame, coming in at 1250g painted in size 54cm. It was a toss-up between this and their extremely lightweight VB-R-077 endurance frame, but in the end, I was swayed by the wider tube profiles and increased stiffness the former had to offer.

I blew about 25% of the total budget on the frame. I opted for rim brakes as I’ve always liked the smoother ride feel, compared to the harsher and unbalanced feeling you get from lop-sided reinforcement of the fork and chainstay required to run disc brakes. For me the benefits of disc brakes just don’t stack up against their downsides.

Some of the main concerns when buying a non-branded frame are the quality of the finish on the points of interaction with the components (e.g. headset bearing seats or bottom bracket shell). I actually found the headset bearing surfaces were smooth with no excess resin or variations in thickness and the bearings sat snug and flush.

I was also happy with the finish on the dropout surfaces, meaning the wheels were easy to centre. The tolerances for the seatpost were spot on and with plenty of carbon paste has not caused any issues.

I purposefully chose a frame with a threaded bottom bracket and would highly recommend this to anyone doing a similar build. Threaded bottom brackets aren’t immune to problems, but from my experience they are much less frequent!

The one issue I had with the frame was some left-over resin around the rear brake mount that meant the recessed nut wouldn’t fit. As a fix, I taped some high-grit sandpaper to a small electric screwdriver head and ground out the excess.

Lightweight carbon wheels

For the wheels I went with the Drive 50v clinchers by EliteWheels, which together with the tyres (Continental GP-5000) and TPU inner tubes have the biggest impact on performance (after your legs!). Given their importance I spent about 50% of my total budget on them. I chose these wheels after watching and reading a lot of reviews.

With a depth of 54mm and bladed carbon spokes the wheels are moderately fast and rigid and therefore a great all-rounder, but their performance is probably most notable on climbs where at 1315g they are ridiculously light wheels of this depth and stiffness.

Groupset options

The groupset is an amalgamation of different parts based around an 11 speed Shimano system. Shimano 105 R7000 makes up the front and rear derailleurs, cassette, and brakes, which I chose specifically for their reliability and durability. There are certainly lighter options available for the brakes, however I would always recommend sticking to a heavier pair of dual-pivot brakes with high-quality shoes and inserts, rather than going for something flimsy, half the weight.

There are plenty of lighter options for the cassette, however the only options worth your money are the titanium machined ones from the big brands, which are five times the price.

I preferred the look of the direct mount Senicx cranks over Shimano, which were also slightly lighter and just half the price. The shifters are another component where I could save some weight and money by going with the Sensah TeamPro 11 speed. The shifters have some nice functionality with both the up and down shift being on the same lever, as well as an adjustable lever reach. The shifters are let down slightly by the lever throw being longer than on some of the newer Shimano models.

Lightweight bike components

The finishing components are where I could make a real dent on the weight savings, with some cost-effective lightweight upgrades. The stem is the ultra-lightweight UNO Kalloy x Litebike stealth stem from 3D forged alloy, which comes in at just 90g for a 100mm length. We've upgraded the version of the Kalloy UNO stem we sell with weather resistant titanium bolts. It's lighter and more durable than most carbon stems, and won't break the bank.

The pedals featured are titanium lollipop, which still look good after thousands of kilometres. Being made from titanium they are very durable and resistant to the elements and continue to look brand new year round. The pair weigh in at just 152g, lighter than any £400 offering from Speedplay.