[Grumpy Select] Gravel Wheelset "Growtac x Industry Nine"

Hello, this is Ikeda from Grumpy.

Right after the new year, we've completed a custom wheelset that Grumpy staff have been eager to introduce to you.

 

This is Grumpy's custom wheelset selection: the "Growtac x Industry Nine".

The great thing about custom wheelsets is that you can choose each component of the wheel to suit its specific purpose.

Our theme for this set was a lightweight wheelset for gravel roads.

Here are the key points:

・It has to be durable enough for gravel riding.

・The tire width should be a perfect fit for the 35-50c range commonly used for gravel bikes!

・It incorporates new standards: "wide rim (inner width 25mm)" and "hookless".

・It must be lightweight, with the wheelset weighing in at around 1200g.

・You should clearly feel the difference when you use it. 

That's the gist of it.

 

Now, let's break down the specifics of this custom wheelset.

 

 

The rim is the GROWTAC EQUAL Carbon Rim RMCD-302530.

EQUAL's carbon rims are still a relatively new brand compared to established names, but they are a noteworthy product that offers carbon rims at an accessible price point.

They are manufactured with a focus on "reliability" and "quality," and when you actually hold them, the rim itself has an extremely beautiful finish down to the smallest details.

The rim has an extremely simple design, without flashy logos.

In fact, the "RMCD-302530" chosen for this gravel road application is a new addition to the EQUAL rim lineup, so many people may not have heard of it yet.

The front and rear rims weigh 653g, which is 326.5g per rim.

※The spokes shown in the photo are not included in the weight.

The RMCD-302530 is a hookless carbon rim. This is one of the most advanced rim technologies, allowing for a lighter weight and higher tire air volume.

Additionally, by placing the spoke holes in an asymmetrical position, the wheel can be tensioned evenly from left to right when assembled.

Spoke holes are available in 24h and 28h.

The rim height is 30mm. This height provides a good balance for various situations such as high speeds, uphill climbs, and long rides.

And what's astonishing is its high cost-performance. It's likely that GROWTAC's conviction to make selective choices based on its unique values is what has created this excellent cost-performance. 

The GROWTAC EQUAL Carbon Rim RMCD-302530 is priced at 38,500 yen per rim, including tax.

If you already own a wheelset, upgrading your rims to carbon while keeping your existing hubs would be a good option!

 

Next up are the spokes and nipples.

For spokes, we chose Pillar's Wing 20, manufactured in Taiwan.

Pillar is actually a major spoke brand with over 40 years of history, engaged in OEM production for numerous brands.

The Wing 20 spokes are thicker at both ends (hub and rim sections) to maintain durability, while the flattened center section makes them lightweight and allows them to cut through the wind during wheel rotation, resulting in a nimble ride.

For the spokes, we chose a 4-cross lacing pattern, using 4 spokes per bundle.

This results in shorter spokes compared to the 6-cross pattern commonly used in general wheels, reducing weight while the 4-cross lacing provides resistance to twisting from both sides.

 

For nipples, we also chose Pillar's MV14. Nipples are small components that connect spokes to the rim. However, since the theme of this wheelset is "lightweight," we opted for aluminum nipples to make them as light as possible.

Incidentally, the weight of 48 Pillar Wing 20 spokes for both front and rear wheels was 226g.

 

 Pillar MV14 nipples for both front and rear wheels, a total of 48, weighed 21g.

 

Next are the hubs.

For the hubs, we chose INDUSTRY NINE SOLiX.

These are newly designed road and gravel hubs made in the USA, introduced last year.

A key point is that SOLiX hubs, like Growtac rims, are available with 24 or 28 spoke holes.

Additionally, their "605" points of engagement are an order of magnitude higher than typical hubs, effectively eliminating unpleasant pedaling losses.

Once accustomed to high-engagement hubs, some people reportedly find regular hubs to feel unnatural... We have test bikes available in store, so we encourage you to experience them for yourself.

For more information on INDUSTRY NINE SOLiX, please refer to this blog post:

What's with the INDUSTRY NINE SOLiX Hubs that are gradually gaining attention?

 

The INDUSTRY NINE SOLiX set, front and rear, weighed 348g.

And here is the assembled wheelset.

 

The "Grumpy Select" Growtac x Industry Nine lightweight gravel wheelset is priced at 228,000 yen (including tax).

The total weight of the front and rear wheels was 1249g.

For a wheelset in this price range, it should be quite lightweight!

Please compare it with wheelsets from other brands.

We will soon have a test ride version of the Grumpy Select wheelset available in stores.

If you are considering purchasing, you can try it out in-store.

Also, you can order with your preferred number of spokes or hub color, so please feel free to contact us if you're interested.