Skip to content

Anatomy of a Dropbar Trailbike

A Dropbar Trailbike is a Cyclocross or Gravel bicycle with clearance for at least two inch tires. This is not only a practical setup for all terrain riding at speed, but is also extremely fun, versatile, and safe. It rides both technical and flowy singletrack trails like a dream. This is a machine built for enjoying the mountain goat experience. Make no mistake, this is not a “do-it-all” “one-bike-for-everything” cross bike hybrid. Once you’ve dedicated to building out a Dropbar Trailbike, it will end up more and more specific for being a great offroad machine and less and less ideal for enjoying adventures on pavement. Read on to learn the basics of what makes a bombproof and super agile Dropbar Trailbike, which is a bike for ALL trails that rides like no other kind of mountain bike.

Road Racing Geometry with Two Inch Tires

A wide variety of cyclocross and gravel bikes could be described as having “road racing geometry”, but only a few of them can fit two inch tires on 700c/29” rims. Maybe a few more could fit such tires on 650b/27.5” rims, which would be acceptable and mostly similar. Bikepacking.com has a good showcase of dropbar mountain bikes for 2019. Most of these bikes can be built up to be a bomb proof trailbike, but not all have the desired geometry. It is absolutely essential for the mountain goat experience that such a bike have the short wheelbase, steep front end, and fore-aft balance that typifies a road racing bicycle. What this affords is the quick handling and dynamic rider positioning that is the hallmark of this type of trail riding. We’ll cover these specifics of mountain goat geometry in a later post. But needless to say, putting drop handlebars and a rigid fork on a mountain bike will not result in the same riding experience.

Dropbars for Technical Riding

The most important aspect about handlebars on a Dropbar Trailbike is that the drops are used. Hands in the drops is the safest and most effective position for maintaining balance and control in technical situations. Period. Whether your drops are low or high, flared or straight, short or deep is more of a personal choice for each individual to make, with priority for maintaining comfort in the drops. These dropbar choices should be made from one’s own experience of having ridden in a few. Handlebar measurement numbers, similar to frame measurement numbers, just don’t translate well for most of us to know what a good fit is. To this point, in future posts I will dive into more specifics on drop handlebars, including: how to effectively use dropbars for technical ridingtechniques for virtual dropbar fitting, to help you in purchasing the right bar the first time; and what all these numbers and labels mean anyway.

Wheels for Rock Rolling

Wheels are the bicycle’s first point of contact with the trail. As such, they are the most important component for ride safety and comfort. However, especially on a fully rigid machine, this proximity to “tera firma” also means that they are the first to contact all the hard hits. This simply adds up to mean that wheels are the first components one should upgrade for reliability and durability.

With stout rims and two inch low-pressure tubeless tires, you’ll likely manage most obstacles without harm. I weight 165 lbs, and run between 20 and 25 psi in my tires. Between this and my ability to dynamically shift weight between the wheels, I rarely bottom out on the rim. But big hits do come. With tubeless tires, a dented rim will just be a constant hassle as it continually losses air pressure. Additionally, with 2 inches of rubber on that rim, you’ve likely maxed out the tire clearance for your bicycle frame. Even small wobbles in the rim could cause wheel rub. Put together both of these delicate tolerances for rim damage, and you understand why I say stout rims matter. This means they’ll either be heavier than most rims, or 10x the price of most rims. I’ll make sure to write more posts on this topic in the near future, including a detailed description of the rims and tires that I’ve destroyed. Until then, don’t be shy of big heavy rims, like Velocity Cliffhangers (not a sponsor). They’re not really as heavy to ride as the hype likes to make them out to be.

Forks for Not Eating Dirt

Forks break too. We don’t think of bicycle forks much, and for good reason. Modern road forks, ridden on the road, and squishy mountain bike forks, ridden off road, don’t usually suffer damage that they are not equipped to handle. But cyclocross forks and gravel forks, on the other hand, can be a toss up when it comes to withstanding the (mild or extreme) abuse that trail riding can dish out. Any particular model might not hold up as well as another model, and there’s not a good way to determine the difference without riding them hard. I’ll tell you all about the titanium cyclocross fork that I broke in a future post. Even better, I look forward to telling you all about other trail appropriate forks for dropbar bicycles that I hope to review in the near future. But for now, just keep this warning in mind as you tear up the trail on your rigid CX fork. It might not be built to withstand trail riding. Check with the manufacturer for its intended use.

A Saddle for Bumpy Bashing

Yes I’m opinionated, but, at least in this case, I’m not discussing a matter of opinion. This is a matter of gross anatomy. Gross in the sense that the fine details that make up the difference between you and me are not gonna matter here. Gross also in the sense that I’m talking about saddles, and the parts that they touch that matter a lot to all of us. In particular, I’m talking about how a saddle can possibly avoid touching these parts. ‘Cause in the context of Dropbar trail riding, touching turns into bumping, and bumping turns into bashing. We don’t wanna bash our soft parts.

Here’s the problem in a four part nutshell. 1) Saddles support us at the soft parts of our lower pelvis. 2) Riding in the drops can expose even softer parts, as the pelvis rolls forward on the saddle. 3) Fully rigid trail riding is really bumpy on the saddle. 4) Bumpy conditions are hard on soft parts which often results in a compromised riding position and/or damage to your parts.

The solution is a saddle designed to protect the soft parts, even when the pelvis is rolled forward. These are usually referred to as triathlon saddles or time trial saddles. Most have a split of some design, which allows the pubic bones to rest directly on the saddle edges without contact to the soft parts in the middle. These are often top of the line and/or niche saddles, that offer free trials through your local bike shop or bike fitter. ISM (not a sponsor) has actually designed a split nosed saddle specifically for MTB riding. It has a slopped and tapered tail end which allows the rider to move more freely off the back of the saddle and back onto it. In the near future, I’ll write additional posts detailing my adventures in saddle fitting, and what to look for in a trailbike saddle. In the mean time, don’t compromise your riding position with a saddle that hurts. Go check out the options that allow you to ride bumpy in a forward position.

Other Components for Bombproof Riding

Hydraulic brakes, dropper seatposts, clipless pedals, and internal geared hubs are all awesome components that make dropbar trailriding a whole lot better. I’ll be sure to write additional posts detailing all of these in the not-too-distant future.

What I Ride

I will go through the nitty gritty details of my own trusty mountain goat, on which I’ve spent the last 5 years building, breaking, repairing, and replacing every single component, in a future post. To be clear, I’m a bit obsessed. I would not recommend any one put the kind of attention or money into their trailbike that I have, unless they have 20 years of good reasons all piled up and ready to dump into a big trial and error experiment. That what Ive done, and how I ended up here.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s