Journal

Big guy mountain bike review: 2018 Kona Process 153 CR 27.5

October 10, 2021

I’ve written several reviews of bikes I’ve owned or been privileged to test from a big guy perspective. These reviews include a mountain bike hardtail, road bike and a gravel bike.

A month before I sold my Kona Explosif, I bought a new-old-stock 2018 Kona Process 153 CR 27.5 in size XL from Icycle Sports. I was looking for a full-suspension bike that was tough, fun and allowed me to ride gnarly trails with more confidence and comfort.

I’ve had other full-suspension mountain bikes before, but more trail-oriented. They included a Rocky Mountain Instinct and a Kona Hei Hei Trail. While I enjoyed these bikes, I found them noticeably flimsy, especially in hard corners and on rough terrain.

In fact, I snapped the chainstay of the Hei Hei after riding it for a year. Kona thankfully replaced the part with something beefier.

The Instinct’s tiny 32mm stanchions on its Fox 32 Float fork and the rear pivots of the bike could visibly be pushed and flexed. The fork was particularly bad.

Big guy problems, right?

This is my review after having the Process 153 CR 27.5 for 2 years. I’ve made a few upgrades, but the bike is mostly still stock.

Flagging a very muddy enduro course in Dawson City, Yukon

What I like

Something that is immediately evident about the Process is that its carbon frame is beefy and overbuilt. This generation of Kona Process bike has a cartoon-like look to its linkages, seat brace, headtube and downtube. The pivots are also fat and chunky.

On big rocks and roots, that stout frame when combined with a RockShox Lyrik fork mean the Process tracks well and takes a lot to knock it off a line. I can get into all sorts of dumb situations and the Process just plows through and saves my bacon.

Yet, that stoutness is also what’s interesting about the Process 153 CR 27.5. It doesn’t feel like a plow, in fact the bike is quite the opposite. The Process is very nimble and poppy, especially with its smaller 27.5” wheels. It’s just a lot of fun.

As I’ve learned to ride the Process as it wants to be ridden – at speed and aggressively – that personality really shows up. For me, this means riding more forward on the bike and leaning into corners and on rooty terrain rather than backing off. The Process rewards me when I push it (and myself) to find new levels.

What I don’t like

I could do without the bike’s stock brakes, dropper post and its stubby seat-tube length and stack height.

Brakes

I had previously upgraded the Kona Explosif’s brakes to a pair of TRP G-Spec DH brakes that I absolutely adored, and still love. Their thick levers and the fact that they never, ever seem to fade has made me a fan.

I took the stock SRAM Guide R brakes that came with the Process and swapped the TRP G-Spec DH in after trying the Guide brakes for a few weeks. There is just no comparison.

Dropper post

This past summer, the RockShox Reverb dropper post caused me no end of headaches.

The Reverb suddenly began getting much slower to raise and lower, and eventually just gave up in both directions on multiple occasions.

I took it to Icycle Sports 5 times in 2021 and they replaced seals, repeatedly bled it and did all their typical troubleshooting, but it just keeps on tanking. I imagine I’ll replace it next year with something more reliable.

Seat-tube and stack height

The seat-tube and stack heigh of the XL are too low for me and my ridiculously long legs and required saddle height. I realize this is the current trend with mountain bike design, but it's frustrating as a taller person.

If my 37” inseam was 2” shorter, the Process would be perfect. As it is with its short seat-tube, the 170mm dropper post sticks very far out of the frame and looks, well goofy.

The front-end of the bike is also too low. To compensate, I replaced the stock Kona handlebar with a ENVE M9 carbon bar with 50mm of rise and some spacers underneath it. That made a noticeable difference in comfort and control.

Getting a higher stack height

Still, as with most mountain bike these days the Process isn't really made for tall people. As seat tubes and stack heights continue to shrink, our bike options get fewer and fewer. Look how far back my saddle is over the rear axle!

Side profile of Kona Process 153 CR 27.5

If I could design my own Kona Process, from a big guy perspective

I’d first switch to 29” wheels to make the big look more proportional.

29” wheels would also be faster and roll over obstacles better than its 27.5” wheels, which sometimes hang up if not riding at speed.

I’d also add at least another 55mm (about 2”) to the seat-tube for more support. I’d do something similar on the front-end of the bike, raising the stack by about the same height.

If Kona sold a 29” version of the Process 153 in a XXL size with these types of adjustments, it would be ideal.

That said, I know people of my stature are probably not a large enough market to warrant a whole new size of the Process. Thus, I and others will have to keep riding these smaller bikes.

In summary

All in all, the Kona Process 153 CR 27.5 is exactly what I wanted: tough, fun and confidence inspiring. I also love the way it looks and rides on a variety of terrain.

If only the frame was bigger.

Kona and other manufacturers, are you listening?