I’m A Personal Trainer, And The Rep Fitness Black Diamond Power Bar Is My Client’s Favorite Bar To Train With. Mine Too!

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One of the last barbells to be released in Rep’s new line is the Black Diamond Power Bar.

This eagerly awaited replacement of their SS Power Bar V2 was recently released, and I couldn’t get my hands on it fast enough.

The old Power Bar V2 was our #1 pick for home gym barbells for years and was my barbell of choice when training for the same period of time.

So is the new bar as good as the old one? Well, not to spoil the surprise, but its not.

It’s a lot better!

Unboxing Video

Black Diamond Comparison

GymCrafter Ratings

*The SS version of this bar scored higher in our testing than the Cerakote. Both scores are shown.

OVERALL

98 | 88

SLEEVES

24

SPIN

24

FINISH

25 | 17

KNURL

25 | 23

Sleeves: 24/25
Radial play: 10 pts.
Lateral play: 9 pts.
Ribbed/Smooth: 5 pts.

Spin: 24/25
Smoothness: 10 pts.
Bushing type: 9 pts.
L/R consistency: 5 pts.

Finish: SS 25/25, Cerakote 17/25
Corrosion resistance: SS-10 pts., Cerakote-8 pts.
Durability: SS-5 pts., Cerakote-4 pts.
Application: 5 pts.
Feel: SS-5 pts., Cerakote-0pts.

Knurl: SS 25/25, Cerakote 23/25
Grip: 10 pts.
Feel: 5 pts.
Terminations: 5 pts.
Consistency: 5 pts.

You can see a detailed explanation of our barbell scoring process here.

The Short Version

The Rep Fitness Black Diamond power bar is one of the best power bars that Rep Fitness has ever made. With knurling that’s appropriate for 95% of all home gyms, multiple finish options, and tolerances that are at or above the best barbells in the industry, it’s easy to see why this is our #1 recommended all-around barbell for home gyms.

The Black Diamond Bar was so good that we had to create another category for our barbell recommendations. We now have a “best dedicated power bar for your home gym” page and a “best all-around barbell for your home gym” page.

While the Black Diamond bar is not our #1 pick for a dedicated powerlifting bar, it is our #1 pick for folks who only want to buy one bar for their garage gym. Why not a “mixed-use” barbell instead? Because mixed-use barbells don’t have a center knurl, which is critical for doing squats, pretty much all people training at home with a barbell will be doing.

If you are going to have only one barbell in your gym, I think it should be this one. The Black Diamond Bar (in stainless steel) is not only my favorite bar to train with now, but it’s also the preferred barbell of the clients I train every day in my garage.

BK Diamond

The Black Diamond power bar features a medium-aggressive volcano-style knurl that is ideal for virtually all movements outside of specialized Olympic lifts. While many thought the knurl on their original power bar V2 was a bit too passive, that won’t be an issue on this new version.

The Black Diamond power bar knurl is very grippy without being overly aggressive. It provides comfort and bite regardless of the weight being lifted. It’s strong enough for those who desire a more aggressive knurl while being toned down enough to appeal to people with no callouses or sensitive hands.

The knurl is also grippy enough for your heaviest deadlifts and is a good fit for high-rep, high-energy movements that normally require a less aggressive bar. It really does sit in the perfect sweet spot for most home gym owners.

The Black Diamond also comes in 6 different finishes, so if you don’t want to spend the extra on end-to-end stainless steel, you can get the same bar for less money.

The knurl and finish application is excellent, and the colors are clean-looking and sharp. This is definitely NOT the case with most Cerakote™ barbells.

To top everything off, Rep adds the best-looking endcaps in the industry and some laser engraving, making this mid-priced barbell look and feel like something much more expensive than it is. I am 100% confident that if you are looking for a single barbell to fit all your garage training needs, you’ll absolutely love this one.

Want to start training with one right away? Head over to Rep Fitness to get your Black Diamond bar now!

Looking for other barbell recommendations? Check out our recommended barbells page.

  • Bar Use – Powerlifting
  • Weight – 20kg (44.1lbs)
  • Length – 86.6″
  • Loadable Sleeve Length – 16.3″
  • Shaft Diameter – 29mm
  • Sleeve Diameter – 50mm
  • Bushing/Bearing – Bronze Bushings
  • Sleeve Style – Smooth
  • Knurl Style – Deep Volcano/Aggressive
  • Center Knurl – Yes
  • Knurl Markings – IPF
  • Material – Steel or Stainless Steel
  • Shaft Coating – Cerakote or None (Stainless Steel)
  • Sleeve Coating – Duracoat™, Hard Chrome, or None (Stainless Steel)
  • Whip – Low
  • Static Rating – 1,500lbs
  • Tensile Strength – 200ksi
  • Tolerance – 1%

Black Diamond Power Bar Pros & Cons

PROS

6 finishes offer a range of prices

Available in end-to-end stainless (our preferred finish)

Medium-aggressive volcano-style knurl

The knurl makes this a perfect all-around bar

The knurl application is excellent

Smooth sleeve spin

Laser engraved branding

Lifetime warranty

CONS

Cerakote dulls the knurl slightly

Cerakote and Duracoat will fade and rub off over time

Knurl may not be aggressive enough for very experienced lifters

What I Like About The Black Diamond Bar

There’s a lot to appreciate with this bar. That’s why it’s my current daily driver. Here are the highlights.

Knurl Type & Quality

When Rep introduced their end-to-end stainless steel power bar V2 (now that’s a mouthful!) a few years ago, it got a lot of good press. Some of that press was from me, as it was my #1-rated home gym barbell for several years.

While I loved using that bar, there were a few things I wished were different. The knurl was one of them. It’s not that I didn’t like the knurl on this original power bar; I just thought it could use a touch more bite.

Rep Fitness black diamond power bar knurl closeup

So when I saw the Black Diamond bar was being released with a completely new knurling pattern, I was very excited. And boy, they didn’t disappoint!

The Black Diamond bar has, in my opinion, the perfect knurling for folks who want to buy one barbell for their home gym (and let’s be honest, that’s most home gym owners). If budget allows, I’d recommend the stainless steel version of this bar, as the Cerakote versions do dull the knurl just a tad.

The Cerakote version is really good. If I hadn’t also felt the stainless steel version, I would never have thought it could be better. If you want a black barbell, don’t hesitate. The Cerakote is well done, and the grip is fantastic.

If you want to maximize grip while still not tearing up your hands, the stainless version is the way to go.

I train 7 clients in my garage gym at this time (3 women and 4 men), and virtually every single one of them reaches for the Black Diamond bar when they come to train. I have 16 bars in the garage for them to choose from, and they ALL pick the same bar.

The only exception is 2 of my male clients are working hard on their deadlifts. For that lift, and that lift alone, they reach for the American Barbell Chewy bar instead. You can read my review of that bar here.

6 Available Finishes

Speaking of finishes, the Rep Fitness Black Diamond bar is available in 6 finish options:

  • Black Cerakote™ shaft with black Duracoat sleeves™
  • Black Cerakote™ shaft with green Duracoat sleeves™
  • Black Cerakote™ shaft with blue Duracoat sleeves™
  • Black Cerakote™ shaft with red Duracoat sleeves™
  • Stainless steel shaft with hard chrome sleeves
  • End-to-end stainless steel
bk on bk dbl

black/black

green on bk dbl

green/black

blue cerakote Rep Fitness double black diamond bar

blue/black

red cerakote Rep Fitness double black diamond bar

red/black

ss shaft, hard chrome sleeve Rep Fitness double black diamond bar

stainless/hard chrome

end to end stainless steel Rep Fitness double black diamond bar

end-to-end stainless steel

But even better than the color options are the price differences. Not everyone will want to spring for the end-to-end stainless option ($449.99 MSRP). The $329.99 MSRP price point of the colored variations makes this bar much more accessible than their old flagship power bar, which only came in stainless.

Finish Quality

In my article detailing the pros and cons of Cerakote™ for a barbell finish, I talk about even application problems as well as how Cerakote™ can often ruin the knurl on a bar by filling it in.

Rep not only applies the Cerakote™ right, but the reduction in knurl sharpness is minimal. A lot of times, you trade knurl quality for a cool, black barbell. While the black Cerakote™ does take a bit of the bite off of the knurl, it’s not a big enough difference to stay away from the black if that’s what you want!

Duracoat™ is also a great choice for a colored sleeve finish. It chemically changes the color of the metal, and it is not an applied coating. This makes it look amazing and last a very long time. I do want to note, however, that the black sleeves do show a lot of marks after being used. It’s not a functional problem, but if you have OCD like I do, it will bother you.

All in all, there are zero issues with the finishes on this bar. It’s applied with precision, and there are no blotches or other problem areas, as you see on some less expensive Cerakote™ barbells.

PXL 20230607 223459076 edited

Poorly applied Cerakote™ on a Bells of Steel barbell

All that said, it’s important to note that ALL applied finishes, including Cerakote™ and Duracoat™, will fade and rub off over time. Stainless and bare steel are the only finishes that will not show this type of wear.

Overall Build Quality

You know how when you close certain car doors they make a very specific and solid thud that tells you the car is extremely well made? Well, that sound describes the Black Diamond Bar too.

This bar screams high-end, from the laser engraved branding to the knocked-off corners of the sleeve’s shoulder. The enameled metal end caps are another great example. You just didn’t see attention to detail like this in Rep’s previous barbell lineup.

Sleeve spin should get its own section, but that’s yet another indicator of just how well this bar is made. The tolerances on this bar should leave no questions about its quality. They also set this bar above most of its competition (more on that below).

What I Wish Was Different About The Black Diamond Power Bar

As much as I like this bar, a couple of things could be changed to make it even better.

The Knurl Should Be Different On the Cerakote Models

In my review of the Double Black Diamond power bar, I pointed out that the Cerkote™ models give users the option to dial back the aggressiveness of the knurling. With a hyper-aggressive bar like that, that’s a great option to have.

But on this bar, that’s not the case. In my opinion (as well as those I train), the grip of the stainless steel Black Diamond bar is ideal. There’s no reason to take any of its bite away. Now, it’s not a huge deal if you get the Cerakote™ version, but the stainless is better.

The solution to this is what top-tier barbell companies like American Barbell do. For Cerakote barbells, the knurl should be cut just slightly differently (usually deeper and sharper) to offset the slight dulling that the Cerakote™ creates.

I wish Rep did this with their bars, especially this one.

stainless knurl

Stainless Knurl

cerakote knurl 1

Cerakote™ Knurl

I Wish The Sleeves Were Hard Chrome, Not Duracoat

I get it. Black barbells are sexy af. So are some of the colored options. And what looks better with those colored bars than black sleeves, right? My first Black Diamond bar (yes, I’ve bought two at this point) was all black.

Out of the tube, that bar looked amazing. After one workout, it did not. As you can see in the picture, the metal from the collar on my bumper plates leaves all kinds of marks on the sleeves.

They mostly clean off, but the sleeves will never again look like they did when they were new. I’m sure my OCD makes me more sensitive to this than many, but wow, do those marks bother me!

Rep Fitness black diamond power bar sleeve
A lot of this cleans off, but not all. Expect the black sleeves to look like this in just a few workouts.

That and the knurl difference is why I now also own an end-to-end stainless version of this bar. Yes, it’s more expensive, but it just looks and feels nicer to me!

The Knurl May Be Too Passive For Some

Even though I run a home gym website and YouTube channel for a living, I’m not a gym rat. I train 6 days a week, but only 3 of those are with weights, and often, only one day is with a barbell.

That means I don’t have the callouses that more experienced or dedicated lifters do. And that’s true of at least 90% of the people who want to train at home. Especially those in their 50s like me.

But for people who are proud meatheads, this bar may not be aggressive enough. If you are under a bar 5-6 days a week, have thoroughly calloused hands, and use more chalk than a billiards tournament, you might want something a bit more aggressive.

And that’s the whole reason Rep makes the Double Black Diamond power bar. You can read my review of that bar here.

The Double Black Diamond vs. The Competition

There is a lot of competition out there for your power bar dollars. Powerlifting bars are one of the most commonly sold barbell types, so everyone makes at least one. Here are the 4 closest competitors to the Black Diamond power bar and how they stack up.

Rogue’s Ohio bar, in one of its 1,027 different configurations, is the single most recommended barbell on the internet. Most sites list it as their #1 choice. If it’s not #1, it’s usually top 3.

Is it a good bar? Yes! It’s a really good bar. Is it as good as the Rep Black Diamond? No.
Is it the single most overrated barbell in the home gym industry? I think it is.

The Black Diamond bar has better knurl, better endcaps, better bar spin, tighter tolerances, and a lower price than the Ohio Power Bar.

rep knurl ring

Rep Fitness knurl terminations

rogue knurl ring

Rogue Ohio knurl terminations

These two images tell an important story. The Rep image is from their Delta bar, a $179 budget bar. The Rogue image is from their $500 stainless steel Ohio Power bar. You tell me which one is better made.

Rogue simply does not have the best manufacturing tolerances across almost all of their bars. The word sloppy often comes to mind when I use a Rogue bar.

Drop an Ohio Power Bar, and you’ll hear it rattling a few miles away. Drop the Double Black Diamond, and it makes significantly less noise… Because it’s got much better manufacturing tolerances and a better internal design.

The only thing that could possibly be considered as “better” with the Ohio bar is that Rogue is made in the US, and Rep is not.

That’s really important to some people, and I’d never discount that for people who care about it.

In Coop’s review of the Double Black Diamond power bar on the GGR YouTube channel, he literally says that the Rep bar is the better of the two bars, but he prefers US-made stuff, so he would go with the Ohio bar.

If you are willing to buy an inferior product because of where it was made, go for it!

Of course, American Barbell crushes Rogue in quality and workmanship, so there’s that. If you want made in the US, I highly recommend American Barbell, not Rogue.

If made in the US is not a huge factor for you, then the choice between Rogue’s Ohio Power Bar and the Rep Black Diamond Bar is easy. Rep all the way.

Speaking of made-in-the-USA barbells, we need to compare this Rep bar to at least one bar by American Barbell. The most comparable is their Grizzly Power Bar.

I own the Grizzly Power Bar. It was the first “premium” barbell I ever bought, and I still use it occasionally to this day.

The Grizzly bar only comes in one finish: A stainless steel shaft with hard chrome sleeves. I’d love it if it also came in an end-to-end stainless version like the Black Diamond, but hard chrome is an excellent sleeve coating that will last many years.

The weld at the shoulder of the sleeve is one of the ways this bar is better than the Rep offering. Outside of that, however, the Rep bar is equal or slightly better in almost every other way.

The Rep bar has much less play in the sleeves. The knurl is grippier while still comfortable, and multiple finishes are a great option for both looks and price.

These bars are close enough (and are basically the same price) that if made in the USA is an important factor for you, the Grizzly bar is an easy choice for you.

I wanted to include the Bells of Steel Onyx Bar because it’s a popular option for folks who want a black Cerakote™ bar at a lower price point.

While it may save you a few bucks, you will be getting a bar that is inferior in almost every way.

First, Bells of Steel has the single worst Cerkote™ applications of any fitness manufacturer out there right now. Second, they put these ridiculously thin shoulders on their bars so “you can load more plates”. First, that’s crap, an extra inch isn’t going to help 99.99999% of lifters. Second, that puts your plates much closer to your rack so when you walk out for a squat, it is very easy to knock the plates against the rack.

There are shoulders on barbell sleeves for a reason. That reason is to provide space between the plate and the rack so the two don’t knock into one another. For the short time I owned a Bells of Steel bar, I hated it. This was a big part of the reason.

Add to that mediocre bar spin, obnoxiously ribbed sleeves, and average customer service and this is a bar I simply don’t recommend.

Rep’s Black Diamond bars are identical, with the exception of the knurling. You can read my review of the Double Black Diamond bar here.

In my opinion, the Black Diamond bar is perfect for about 95% of all home gym owners. But there is a small group of serious, long-time lifters with a large amount of callouse on their hands. Those folks typically prefer a much more aggressive barbell.

If this is you, the Double Black Diamond is the way to go. Just make sure you know what you are getting into. I’ve talked to several people who bought the Double Black Diamond and then returned it as it was too aggressive.

Alternatives To The Rep Fitness Black Diamond Power Bar

So, the Black Diamond isn’t the bar for you, but it’s close? Here are a few alternatives that might fit the bill for you…

The American Barbell Grizzly Bar is a comparably priced power bar that’s made in the US. If having your bar made in the US is important to you, this is your best option.

The Rep Fitness Delta Basic Bar is your choice if budget is your primary concern. No, it’s not as nice as the Double Black Diamond, but at $179.99, no one expects it to be. What it is is the best power bar you can buy at that price point. There isn’t anyone else even close. See why I say that in my full Delta bar review.

The Verdict

Most home gym owners will only ever own one barbell. In my opinion, that bar should be a power bar with a medium aggressive knurl. That will allow you to do pretty much anything you would want to do in a home gym.

It also makes sense that if you are only buying one barbell, it should probably be a nice one. It doesn’t have to be an $800 top-of-the-line bar, but if you can, you should step up beyond the budget bar category.

The Rep Fitness Black Diamond bar checks all of those boxes and then some. It’s my favorite power bar on the market today for home gyms, and that sentiment is echoed by all of the people who I train in my garage every week.

Head over to Rep Fitness and pick out which finish you want in your garage gym today.

FAQ

I heard that Rep’s stainless steel bars rust. Is that true?

With their previous power bars, the ss power bar v2 and the ss power bar EX, there were reports of rust. And there were enough reports of rust that I tend to believe them.

I own both of those bars and have zero rust on either. I do clean and maintain my bars regularly, so that probably makes a difference, but I think the bigger difference was where you lived.

I am not a metallurgist, but I can tell simply by looking at the new bars next to the old (and next to my American Barbell Chewy bar) that Rep has stepped up their stainless game.

I would not be concerned about rust on these new bars at all.

I don’t like that Cerakote dulls the knurl a little.

Then don’t buy the Cerakote version.

There are only two ways to ensure the best, most direct connection to the bar with nothing changing its feel: Buy bare or stainless steel. Otherwise, every single finish that can be applied, including Cerakote, slightly dulls the knurl.

If your primary concern is color, go with Cerakote. If it’s feel, go stainless. You can’t have both.

Do they make a bar with a 2,000 lb load capacity?

No. And they don’t need to.

First, no one can do anything with a barbell that would be better with a 2,000 lb bar vs a 1,500 lb bar.

Second, if you need a bar that can hold more than 1,500 lbs, you’re not shopping at Rep. You need to go to Eleiko and look at $1200-$1500 IPF spec power bars.

Rep Fitness Double Black Diamond Power Bar
Double Black Diamond Bar Review

The Double Black Diamond Power Bar is Rep's flagship powerlifting barbell. Available in 6 different finishes, all with an aggressive, powerlifting friendly knurl, the Double Black Diamond is a great choice for a garage gym.

Editor's Rating:
4.5

Pros

  • Great knurl
  • Precise construction
  • Multiple finish options

Cons

  • Knurl may be too aggressive for some
Photo of author

AUTHOR

Tim Steward has been training at home since he got his first weight set from Sears in junior high. Over 30 years later, Tim has helped thousands of people build home and garage gyms that they love and use regularly. He also holds CPT and Nutritionist certifications with the ISSA and is an NCCPT nationally accredited trainer. When Tim is not training or writing about home gyms, you can find him at the dog park with his two Australian cattle dogs, Anny and Beans.

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