OneUp Underbash ISCG05 Compatibility

I’m planning on putting some sort of bash guard on my bike, and was going to pull the trigger on a OneUp Underbash. Only problem is that OneUp states the Underbash isn’t compatible with frames using 3 ISCG05 tabs:

To me that seems very peculiar. Any idea why that might be the case here? Considering they adhere to the same standard, why would 3-tab be any different from 2-tab?

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Not sure why it wouldn’t work, but you can get the bashguide, I have it and its sweet. Its basically the underbash with a chain guide added.


It’s only a guess, but a 3-bolt tab would have been designed to have something mounted to it using all 3 bolts, while the 2-bolt tab is beefed up for the added stress. If you only use 2 out of 3, you risk breaking off the tab(s). Although it’s probably low risk, OneUp is just covering their butt in case someone runs a 2-bolt bash on a 3-bolt tab.

I have the OneUp ISCG bash guide on my bike and it has been flawless. The added security of the upper guide is nice too.


Good point, I hadn’t considered that angle

@margareefisher Me neither! Sounds plausible tbh. Better to err on the side of caution and buy a bashguide instead since it’ll use all three mounting points to distribute the possible load better.

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The OneUp bashguide is incredibly tough based on what my bash plate looks like. And like @Jetter said, it distributes the forces better. Some new frames only have 2 tabs on them for a taco bash, but they would be designed differently. If you’re looking for a guide send me a message as I can get them from OneUp via my suspension service company Granite Suspension.

I have been running their bashguide ever since it came out, and I used the top guide before that too. The stuff just works, it’s not heavy, and each piece comes with lots of spares for bolts, adaptors and different sized bash plates for varying chainring sizes. All the thumbs up. Perfect product, will buy again.


100%, I have a few One up items now and they are all top notch

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@a.mart Sent you a PM. Happy to support local :slight_smile:


I prefer Blackspire for bash/guides and chainrings, Made in Delta, BC.

I had the Blackspire Crusher on my bike before (now sitting in a spare parts box) and while it worked well overall, the chainring range leaves a bit to be desired. I run a 32T oval, which is similar to a 34T at the widest point, so their 26-32T option wouldn’t protect the chain/chainring, so I went with the 32-38T option. That protected the chain/chainring, but hung down way too low and was always getting hung up on stuff. I ended up running it without the plastic bashguard and used the aluminum mounting plate as the bashguard. It worked, but not ideal.

The OneUp equivalent comes with multiple size bash plates so you can run the small one that will give you full protection of your chain/chainring, while also giving you the most ground clearance possible. Depending on the chainring size you run, it may or may not be an issue, but certainly worth noting.

I hate how Blackspire insists on putting massive graphics all over everything they make. A little subtlety would be nice, and while it’s great that it’s made in Canada, the thought they put into their engineering leaves a little to be desired. Don’t get me wrong, I own a bunch of their stuff, but it will never be my first choice.

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