Reply
Results 1 to 5 of 5
  1. #1
    Registered User userXUSWBEOJHL5's Avatar
    Join Date: Feb 2022
    Age: 52
    Posts: 1
    Rep Power: 0
    userXUSWBEOJHL5 is on a distinguished road. (+10)
    userXUSWBEOJHL5 is offline

    Adjustable dumbells - actual weight vs advertised weight

    I bought a set of powerblock U50 adjustable dumbells about 10 years ago which I was really happy with, however I left them outside for a few years and they got corroded. I decided to get a new set, but the company that sells Powerblock dont have stock for a few months, so i found a guy who sold some that looked identical to the original powerblock U50's, but he told me they were similar but not Powerblock brand. They were advertised as going from 10lbs-50lbs.

    I got them home and I had a feeling they felt a bit light. I checked them on a scale and the total weight is only 45lbs, not 50lbs. All of the increments were out by about 3-5lbs.

    I was tossing up between an expandable set up to 90lbs, or a fixed set up to 50lbs. I went with the fixed set of 50lbs becuase i though that was just about enough and it had smaller increments, but If i had known they only went to 45lbs i probably wouldnt have bought them. By the way they were $500AUD compared to $700AUD for the powerblocks.

    Is this normal?? Would you be pissed if this happened to you?
    Reply With Quote

  2. #2
    Registered User air2fakie's Avatar
    Join Date: Jul 2019
    Age: 52
    Posts: 6,758
    Rep Power: 22795
    air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000) air2fakie has much to be proud of. One of the best! (+20000)
    air2fakie is offline
    It's prob normal if you "found a guy" who sold obvious & admitted knock-offs. I would've just bought a reputable brand so it wouldn't have happened to me.
    Reply With Quote

  3. #3
    joe joewattie's Avatar
    Join Date: Jul 2004
    Location: rochester, ny
    Age: 75
    Posts: 213
    Rep Power: 2998
    joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500) joewattie is a glorious beacon of knowledge. (+2500)
    joewattie is offline
    Sounds like Metric "approximations" gone awry?
    joe Henry
    Reply With Quote

  4. #4
    Registered User xdoomhammerx's Avatar
    Join Date: Sep 2013
    Posts: 70
    Rep Power: 348
    xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50) xdoomhammerx will become famous soon enough. (+50)
    xdoomhammerx is offline
    No adjustable dumbbells will be 100% accurate. However, depending if it's the original or a knockoff the accuracy will be affected.

    A while ago, I weighted my powerblock sports 9.0 and 2 sets of IronMaster because I sometimes felt that there were slight imbalances between both sides when lifting (Mostly on IMs but I dit the PB while at it). See below for a quick summary of my observations, but my conclusion was that I have a noticeable weaker side as the difference of weight is negligeable in most cases.

    Powerblock:
    The plates are within ±2% of the stated 10lbs weight
    The handles are the least accurate part (at least for my set) as they weight 21% (±1.06 lbs) less than the stated 5lbs weight.
    The cylindrical handle add-ons weight are the most accurate part as all four weight exactly 2.4lbs, just 4% off the stated 2.5lbs weight.
    If you put all of the least heavy parts on the same side and all of the most heavy parts on the other, you get a difference of 0.5lbs (88.6lbs vs 89.125lbs)
    The accuracy is as it's worse below 20lbs but improves as you get closer to the max weight (this is due to the fact that the rods connecting both endplates are longer, thus heavier).
    Since the plates cannot be in multiple ways as their loading order is set with the length of the connecting rods, the difference between both sides is negligeable.
    Conclusion, less than a 1lb under the stated weight, wich is pretty good in my opinion.

    IronMaster (worse, and older, of the 2 sets, hence the one I sold):
    The 2.5lbs plates were, on average, ±10% under the stated 2.5lbs weight
    The 5lbs plates were, on average, ±4% under the stated 5lbs weight
    The handles were the most accurate part (at least for my 2 set) as they weight 4% (±0.04 lbs) less than the stated 10lbs weight (using the short screws, long screws add another 0.8lbs).
    If you put all of the least heavy plates on the same side and all of the most heavy plates on the other, you get a difference of 1.65lbs (70.99lbs vs 72.64lbs) in 75lbs configuration and 2.46lbs (114.61 vs 117.07lbs) in 120lbs configuration.
    So if you end up using all the most heavy plates on one side for a low load, let's say 35lbs, the difference of weight between both sides will be more noticable at 1.13lbs (33.08 vs 34.21lbs), but still negligeable for most people.
    Conclusion, more versatile that the PBs but what they gain in versatility, they loose in accuracy at you can end up ±5lbs below the stated weight.

    What I take from this is that in most cases there won't be a significant diffrence from both sides, at least not enough to be noticable. However, if you buy an adjustable dumbbell set, expect it to be below the stated weight due to production tolerances.

    I ended up using that experiment to create pairs/sets of weight so that both sides will be as evenly loaded as possible. The attached graphs are showing the optimized weight parings I ended up with. And yes, I'm an engineer, which explains why I went overboard with this (OCD) lol.
    Attached Images
    Reply With Quote

  5. #5
    Registered User Greybird2's Avatar
    Join Date: Jan 2016
    Posts: 1,316
    Rep Power: 3379
    Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500) Greybird2 is a glorious beacon of knowledge. (+2500)
    Greybird2 is offline
    So, to be clear, you buy junk and are upset that it is junk?
    Reply With Quote

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts