OneUp Components Bash Guide Review


Words by Robert Johnston  |  Photos by Finlay Anderson

These days there are an increasing number of people opting to go without a chain guide and bash guard. But for their roughly 100g weight penalty, concentrated in the least impactful (but most likely to impact.) area on the bike, we’d suggest they’re still worthwhile items to fit to any sort of mountain bike designed to descend down rough and rugged terrain. Some models make life difficult by relying on fiddly spacers on the ISCG bolt holes to tune their fit on the bike, but in true OneUp style, their Bash Guide uses a well-engineered design to make setup easier without detriment to the performance. Read on to find out how it performed over the last few months of punishment on some of Scotland’s gnarliest enduro descents.


The OneUp Bash Guide is their take on an upper chain guide and lower bash guard, built around an 8mm thick machined 7075-T6 aluminum back plate. The upper chain guide and bash guard are made from Reinforced Nylon to offer the desired strength and sliding characteristics. Black stainless-steel hardware is used throughout to retain the stealth looks and ensure the guide stands up to seasons of abuse without corrosion.

The upper chain guide has a toolless “flip” function, letting you twist the outer plate out of the way to let you fit and remove the chain and chainring easily. The OneUp Bash Guide uses a spacer system where the back plate remains in place and an included gauge is used to determine the optimum number of 1mm spacers to go behind the upper guide (max. 5), making for much less fiddling and a more dialed setup without experimenting. If required, 2.5mm spacers can be fitted behind the back plate to increase the total adjustment range to 7.5mm, which should fit just about every bike on the market.

The lower bash is provided in three different sizes, to suit 28-30t; 32-34t and 36t chainrings, and the upper guide will slide to match this size range, with enough wrap around the chainring to let you run an oval unit if that’s your thing. Including the hardware, the OneUp Bash Guide with 34t lower bash tips the scales at 104g and will lighten your wallet to the amount of $94.50/£94.50, with only the black colorway offered.

OneUp Components Bash Guide Review


After testing most of the components in the OneUp range, it’s safe to say their engineers place high value in how user friendly their products are. The OneUp Bash Guide proved no exception to this statement, offering up one of the most straightforward chain guide setups I’ve yet to complete. Simply bolt on the backplate to your ISCG mounts (which can be done without removing your cranks), then use the included gauge to measure the gap between your chain and the upper guide and determine how many spacers you need. You add these spacers, then adjust the vertical position of the guide so that the chain indicator mark lines up, then you’re good to go. It took me five minutes on multiple different bikes with multiple different chainring sizes to get things dialed in and proved to be a spot-on initial setup for all of them.

In use, the OneUp guide goes about its business with minimal fuss. If we exclude the numerous impacts between the bash guard and rocks and roots on the trail, the only “peep” I heard out of it throughout testing was on a couple of severe g-out landings, which made the chain flap violently and hit the upper guide. To prevent these, some rubber lining the inside surfaces of the guide would be nice to see, but I’m not certain it’s necessary to add more complication. I’ve seen riders add stick-on rubber to their chainguides in the past, so if you really need the ultimate silence, it’s likely something you could fit yourself.

Speaking of impacts, I’m certain the OneUp Bash Guide has saved me from chain or chainring damage on more than one occasion, but the bash guard isn’t showing too many signs of duress, only a few gouges. One of these impacts was harsh enough that it had me carefully inspecting the ISCG tabs on the frame to ensure they were still intact, so I was amazed to find the entirety of the guard still in one piece and ready to save the day again.

There’s been no chain drops or jams, and no added friction when pedaling at any point during testing. Given that the weight penalty is minimal, fitting is so straightforward, and the price is no more than a replacement chain and chainring (which it would likely avoid you having to replace at some point) I don’t see any reason why you wouldn’t equip an aggressive mountain bike with one of these.

The Wolf’s Last Word

Well executed and effective, the OneUp Bash Guide is a stellar chain guide offering that I’d highly recommend.

Price: $94.50 / £94.50

We Dig

Simple setup
Effective protection

We Don’t



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