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Gravel BikesReviews

Test Koga Colmaro Extreme: Travel gravel bike with an extremely beautiful aluminum frame

16 April 2024 by Caspar Gebel

Test Koga Colmaro Extreme: The travel gravel bike in the classic look of the Dutch manufacturer impresses with invisible tube transitions and surprises with a 650B wheelset. The equipment and driving characteristics are great, as is the price - and the bike can also be moved in a sporty manner.

At Koga, the traditional supplier of touring bikes and racing machines, the focus has recently been increasingly on gravel. It started with the beautiful aluminum bike Colmaro Allroad with racing bike geometry and space for 35 mm wide tires, which of course has its limits in the terrain. The Roqa announced for next year will be just as sporty, but more suitable for off-road use - a gravel racer made of carbon with 45 mm tire clearance. The Koga Colmaro Extreme, on the other hand, relates more to the company's touring bike DNA.

 

Koga Colmaro Extreme: elegant look typical of the brand

Of course, “extreme” is relative. First of all, the gravel bike looks rather harmonious in the typical Koga look: Dark blue metallic paint with copper decor, which goes perfectly with the Tanwall tires, covers a frame that shines in the upper area with practically invisible tube transitions. If you think the Colmaro is a carbon bike at first glance, we apologize!

Koga Colmaro Extreme
You rarely see aluminum pipe transitions as smooth as those at Koga.
Koga Colmaro Extreme
The Koga looks almost like a carbon frame at the seat tube node.

The geometry isn't really extreme either. Koga offers four frame heights in which the head tube grows by 30 mm each - from 120 to 210 mm. When it comes to seat length, the smallest and largest frames are separated by just 13 mm. However, the Colmaro Extreme isn't exactly short; The sitting position is sportier than you would expect from a touring bike. So you have to be careful when choosing the size.

The font has become more modern, but the colors are typically Koga.
Trains and cables are routed internally.

However, the price is extreme, namely extremely cheap. For 2.499 euros, the Dutch not only deliver the beautiful frame, but also a Shimano GRX 600/800 with 2×11 gears, as well as a high-quality DT Swiss G1800 Spline wheelset. So the overall package is right - but what does the Koga Colmaro Extreme look like in detail?

Travel gravel bike with many attachment options

In keeping with its intended purpose, the bike is equipped with all sorts of threaded holes - mudguards and carriers can be attached, as well as three bottle holders and a small top tube bag. What is striking is that at Koga, every screw is equipped with a plastic washer - a sign of the great quality awareness of the in-house assembly. Shift cables and brake lines are routed to the bottom bracket in the down tube, and the front brake line runs through the fork. The screwed BSA bottom bracket is always good when it comes to assembly, maintenance and spare parts supply.

The GRX-600 crankset is optimally graduated at 46/30.
The gearshift works precisely and the range of translations is large.
Even without ServoWave, the Shimano brakes are great.

Shimano group with top function

There are no discussions about the components: The GRX 600 is functionally equivalent to the more expensive version; Only in a direct comparison do you feel that the 800 STIs shift slightly more crisply. And the crank installed on the Koga may be a little heavier than the hollow-forged GRX FC-RX810, but it may have a more suitable gradation. At 46/30 instead of 48/31 it has a slightly shorter gear ratio, which is a good thing, especially for gravel. Together with the 11-34 crown there is a very large translation range - and then there is the matter of the development...

The 650B wheelset ensures maneuverability, but also lowers the bottom bracket.
The WTB Byway rolls quickly on the road.

Koga Colmaro Extreme – Handy thanks to the 650B wheelset

A special feature of the Koga is the 650B wheelset. On the one hand, the smaller diameter of the rims ensures that the wheel feels quite manageable despite the large tire volume, but on the other hand, it reduces the rolling circumference and thus the unfolding - i.e. the distance covered per crank revolution. With the Koga, the plan works, because the aluminum Geravel bike can be steered with ease and, despite its not exactly light weight, appears extremely lively. With smaller frames, the 650B wheels also create a harmonious look.

Koga Colmaro Extreme
Our test driver wears them Gravel shorts Virginie  and Gravel cycling jersey Barbara from Café du Cycliste, plus the helmet Abus Stormchaser in beige.

On the other hand, due to the smaller radius, the bottom bracket is closer to the ground - compared to a 622-40 tire, around 10 mm, and with the 622-45 even 16 mm. This is something to keep in mind when riding the Koga on trails. Of course you can also ride the bike with 28-inch wheels; Then there is enough space for 45 mm wide tires, maybe even more.

Koga mounts WTB Byways in a width of 47 mm, which roll easily and smoothly with a slick tread, but do not have a very strong profile on the sides. Wet, muddy surfaces are not necessarily this tire's forte.

The handlebars are unusually shaped, but are easy to hold.
If you want more comfort, you can retrofit a carbon support - unlike the Colmaro Allroad.

Unusual handlebar shape

There are smaller surprises with the add-on parts. The quick release on the seat clamp is only on the test bike, but the unusually shaped handlebars are standard: the top link is oriented slightly towards the rider and slopes towards the outside and then rises again in the upper curve. Depending on the grip position, this leads to subtle, quite pleasant changes in the position of the hands and arms. The aluminum seat post is not D-shaped like the Colmaro Allround, but round with a standard diameter of 27,2 mm. Although the bike is by no means hard, you have the option of retrofitting a comfortable carbon support.

The Koga only leaves something to be desired when it comes to weight. Including pedals, it weighs just over eleven kilos - almost one and a half kilos more than the Colmaro Allroad with SRAM Rival 1×11 and identical 28-inch wheelset. Luckily, weight isn't that important when cycling with luggage, and the bike doesn't seem a bit sluggish even when used for sport. If you look at how many gravel bikes you can get from Koga at a manageable price, it won't be difficult to decide on this bike.

www.koga.com

Click here to test it Koga Colmaro Allroad:

Testing the Koga Colmaro Allroad: Aluminum classic for easy terrain

Published: 16. December 2022

The Koga Colmaro Allroad remains true to its position between a racing bike and a gravel bike. Many details on the beautiful, classically styled aluminum frame are new; However, for all-round good driving characteristics, a shorter stem is required. Given the very attractive price for 2024, this is definitely still possible! The Dutch premium provider is just as much a specialist in touring bikes as […]

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Conclusion: Koga Colmaro Extreme

Pro

  • Very nicely made aluminum frame
  • High quality Shimano GRX 2x11
  • DT Swiss wheelset
  • Good driving characteristics

Contrary to

  • Rather heavy

Facts

product year2024
Price2.499 Euros
Web www.koga.com

Overall rating

92%

Value for Money

91%
Designed primarily as a travel gravel bike, the Koga Colmaro Extreme appeals with its beautifully crafted frame to which all sorts of add-on parts can be mounted. The equipment is high quality, especially considering the low price; the 650B wheelset improves driving characteristics. However, standard wheels with 45 tires can also be mounted. Depending on the frame size you choose, you can sit on the Koga, which is not particularly light, in a sportier or more touring style.
Tags:#VMgravelfeaturedGravelGravel Allround 2024Gravel BikesWhoKoga Colmaro

More than Caspar Gebel

Caspar Gebel has been on a racing bike for 40 years. The specialist journalist and non-fiction author works for Velomotion and also for the magazines Procycling and Fahrrad News.

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