BowFlex SelectTech 840 Kettlebell Review: One Dial, Six Weights, a 40 lb Cap
By The Ironnook Test Desk ·
6.6
bowflex.com
The verdict
The 840 is a convenient bell for beginners and small flats: six weights from 8 to 40 lb in one dial, with a smooth shell and a comfortable handle. It is not a replacement for cast iron. The plates rattle on swings, the body is bulky, 40 lb is a low ceiling, and $149 buys more iron elsewhere.
Best for: Beginners in small flats who want one bell for light circuits
What we liked
Dial changes the load in seconds across six settings from 8 to 40 lb
Smooth plastic shell has no exposed metal to bruise a forearm
Textured handle holds without chalk and fits two hands for swings
One bell stores in the footprint of a single kettlebell
30-day return window and a two-year parts warranty
What could be better
Tops out at 40 lb, too light for heavy swings or snatches
The 552 is still the quickest dial dumbbell to use and the cheapest way to replace 15 pairs, but it asks for trust the brand has not fully earned. The recalled models dropped plates on people, the redesigned Results Series adds metal locking tabs, and the dial housing is still plastic. Buy it on sale, treat it kindly, and never drop it. If you lift heavy or rough, buy a PowerBlock or Nuobell instead.
The S 5100 is the adjustable dumbbell for lifters who miss the feel of a real one. Twist the handle and both ends change in a second, the shape stays compact enough for flyes, and 100 lb a hand covers serious pressing. It costs $999 a pair, the dumbbells are not meant to be dropped and the stand is fussy. Buy it if you lift heavy and have money. Otherwise PowerBlock or Bowflex do the job for less.
8.0$999
Only six settings, with 8 and 10 lb gaps between the middle steps
Plates rattle during swings and cleans, per several independent reviews
Wide shell crowds the wrist in the clean and rack position
At $149 it costs more than a pair of cast-iron bells in the same range
The $149 SelectTech 840 swaps six cast-iron bells for one dial and a plastic shell. It handles swings and goblet squats, but it rattles, runs bulky and stops at 40 lb.
Cast-iron kettlebells are cheap, honest and impossible to break. They are also six separate objects if you want a proper range of weights, and they sulk in the corner of a flat. BowFlex's answer is a single dial bell that claims to replace six. We wanted to know whether it can survive the one movement that decides everything for kettlebells: the swing.
What the dial actually gives you
You turn a dial on top of the bell and it picks up 8, 12, 20, 25, 35 or 40 lb of plates. That is six settings, not a smooth ladder. The jumps from 12 to 20 lb and from 25 to 35 lb are the awkward ones, and the FitRated review makes the same complaint when it sets six increments against the 15 or 17 on a typical adjustable dumbbell.
The selection dial on top of the bell sets the load from 8 to 40 lb.
The plates sit inside a plastic housing. Nothing is exposed, so nothing snags your forearm, and the edges are smooth where the bell touches your wrist. The price of that tidy shell is bulk: the maker lists the body at 8.8 inches long, 7 wide and 12.5 tall, which is wide and squat next to a 35 lb iron bell. At 8 lb the bell is still the size of a much heavier one.
The bell is wider and more cylindrical than a cast-iron kettlebell.
Swings, cleans and where the shell shows
For the swing, the bell is fine. The handle is wide enough for two hands and the texture holds without chalk. Reviewers at Home Gym Guru note that larger hands find the handle narrow in a two-handed swing, and that the centre of mass shifts with each setting, so each setting swings a little differently from the last.
The bigger issue is sound. The plates shift a little inside the housing, and every independent write-up mentions rattle on swings and cleans. It does not feel unsafe, it just feels like gear rather than iron. If you train above a neighbour, that sound matters more than it would with a silent lump of iron.
Cleans and presses are where the size hurts. A wide body makes the forearm rotation crowd the wrist, and the rack position never feels as locked in as it does with a compact bell. Snatches work, though we would still rather do them with a cheap cast bell. Garage Gym Reviews scored it 4.1 out of 5 and called it a fit for circuits and beginners, and poor for overhead or competition-style lifting.
Product-page image of the 840 in use for swings.
The 40 lb ceiling
This is the real limit. Anyone who trains regularly outgrows 40 lb for two-handed swings within months. It is a good fit for goblet squats at the lighter weights, rows, halos and conditioning circuits. It is a poor fit for anyone whose goal is to get strong at the kettlebell itself.
Because the dial only changes the one bell, the six settings hide the cost of owning six things. They also hide the cost of one failure: if the dial mechanism wears out, you lose every weight at once. The warranty is two years on parts, per the maker's specifications.
The steel plates stack inside the housing and are picked up by the dial.
Price and the app
The bell costs $149 on BowFlex's site, and the maker advertises $29 off when you buy two, which brings a pair to about $269. That is not cheap. Plain cast-iron bells in this weight range usually cost less per pound, so you are paying for the dial and the saved floor space.
BowFlex pushes the JRNY app with a trial, then $11.99 a month or $99 a year after the trial ends. You do not need it, and we would not pay for it to swing a bell. Returns run 30 days after delivery for a full refund minus shipping and handling.
Who should buy it
Buy it if you have a tight space, you are new to kettlebells, and you want one object that covers goblet squats, rows, carries and light swings. Skip it if you already lift, if you plan to do heavy swings, or if you have room for two cast bells. For most people reading this, two iron bells will serve better for less, and last for decades.
We liked how little thinking the dial needs. We did not like paying $149 for a bell that stops at 40 lb and rattles when you ask it to move.
These are the adjustable dumbbells for people who outgrew Bowflex. The all-steel build, the 34 mm knurled handle and the 125 lb ceiling feel like fixed dumbbells, and the lifetime warranty backs that up. They cost $899.99 for the 65 lb pair and $1,499.99 for the full 125 lb set, and the pop-pin changeover is slower than a dial. Heavy lifters should buy them. Anyone who stops at 50 lb should save about $700.
