Bike weights - why are manufacturers dishonest?


I bought a nice mountain recently, a Niner Jet 9 RDO. On Niner’s website, the weight for my build is listed as 28.8 lbs. It does say “approximate weight” but anyways.

The bike comes stock with 2,000g wheels & 2,000g tires, plus a basic alloy stem/handlebar. I switched these out for carbon wheels that are 1 lbs lighter, tires that are 0.5 lbs lighter, and cockpit that is another 0.5 lbs lighter. I put the bike on the scale, thinking it should read around 26.8 lbs, but instead it said 28 lbs…

I had a similar experience with two other high end mountain bikes (a Santa Cruz and a Yeti). I have also seen several high end carbon road bikes that come through our shop weighing significantly more than claimed.

To be clear, I don’t really care about weight that much. What I do care about is that manufacturers seem to be lying to us consumers and getting away with it. Well, actually I don’t care that much about that either but just venting :slight_smile:



I think the bike did turn out pretty nice though, so I will take that as a good consolation prize :grinning:


one reason is that different frame sizes obviously have different masses

1 Like

Santa Cruz once told me it is about .2 lbs difference between frame sizes for a typical full suspension frame. I imagine Niner is similar.

You’re blaming Niner but you didn’t weigh any of the other components? I think you could be a bit more scientific in your approach to figure out where this extra weight lies.


So you’re thinkin that you bike weight is off by 1.2lbs, call it 550g… what pedals did you install? How much sealant did you put in your tires? Which size is the quoted weight for vs which size did you buy? Half, or more, of your 660g is in those pedals… not sure what those are from the picture but I know my XTR Trails are 350g or so and I’d bet those are in that range. Tubeless sealant is roughly 30g per ounce… you don’t say what size your tires are but, assuming a 29x2.4 tire, you’d be looking at 3-4 ounces per tire so you’re talking about another 180-240g of sealant. Between sealant and tires and frame size difference, you could easily be looking at 600g or more in weight.


they probably won’t even include the brake fluid in the quoted supplied mass


It’s when frame weights are miles off there’s even less excuse, as that is directly in the manufacturer’s control.

A friend of mine recently rebuilt his bike (well-reviewed but quite niche British brand), and the frame weight is cited as being c.1900g on their website. On the scales it was 2230… He rides a size 51, so it’s not like he’s on a 62.

I believe there was also quite a well-documented case of someone weighing an Aspero frame at over 200g heavier than claimed (I’m thinking Luescher Teknik, but could be wrong).


I weighed the bike without pedals; I am not that dumb :slight_smile:

I added 6 oz of sealant, which is roughly 180g / 0.4 lbs. Niner lists Stan’s sealant in the spec sheet, but yeah, they probably weigh the bike without it (they don’t list pedals, so it is fine that the quoted mass doesn’t include them).

I also weighed the fork separately, and it was within a few grams of the claimed mass. Same for the dropper seatpost and brakes (I switched out to Guide RSC). Based on my experience, SRAM is fairly honest with their quoted masses.

So between the sealant and the frame size difference, there is still a little over 0.5 lbs unaccounted for.

Again, I don’t really care about 0.5 lbs that much, especially given how much I weigh :slight_smile: It was just a rant brought on by the disappointment of expectation not matching reality…

1 Like



You have a total 550g unaccounted for weight vs expectations… -180g of sealant and you’re looking at 370g or so of weight. That could easily be accounted for in frame size difference, which you still haven’t said what size frame you’re on, and manufacturing variables in parts and frame. Unless you want to disassemble your bike and weigh everything individually I’m really not sure what you’re looking for here. The weight isn’t out of line at all, nobody is being dishonest given that Niner themselves quotes on their page that actual weights may vary by +/- 10-15% and you’re well within a 2000g range. And given that you keep saying you don’t care, I’m really not clear on what the point of this post even was. Is this just a weird flex for you to say you got a new bike without saying “hey, look at my new bike?”

1 Like

Many (most?) manufacturers will weigh their frames as stripped down as possible…no derailleur hangers, no WB bolts, no seat clamp, etc.

I’m guessing that the weights above are for frame and fork, in which case they also would have pulled out the headset, etc.

1900g is frame only, and he weighed frame only (he says, which I have no reason to doubt).

Tbf, I didn’t see him take off take off the seat clamp or derailleur hanger, and both were on the frame when I saw it. But I can’t see those things totalling over 50g…

That seems quite a lot, though I get that most of the components aren’t within their control. I suppose it allows for cumulative error, in the unlikely event that multiple components are all a few % over.

I’d certainly regard a 15% difference in the published vs actual weight of a bike I’d purchased as material, albeit perhaps more so for a road bike. If you think how much money people spend to save much, much less than 2000g… Ok, that’s not a likely figure for a road bike, but if I bought (say) a Spesh or Giant advertised as 8.0kg in a medium, and when I weighed it it was 9.2kg (+15%), I’d be mighty irritated.

1 Like


Wait…MTB, road or gravel?

It is the manufacturer claiming total weight for a product (the complete bike) that they sell, and they are responsible for the accuracy of this claim. They should be measuring the weight of complete bikes, and advertise the correct weight for the complete product they sell. If component manufacturers misrepresent the weight of their products, that doesn’t give the bike manufacturers a pass.

Road - steel frame

Well yes, I’m all for holding manufacturers to account, but in fairness you can’t weigh every bike that leaves the factory, and you can’t control the weight of other manufacturers’ components.

Let’s say you sell a road bike that you expect to weigh 8kg (based on adding up everything). If you know your frame weighs 900g and, and your forks 400g, that means 6700g of the bike isn’t under your control (assuming you make none of those parts yourself).

Now if all of those parts have weights accurate to 3% (pretty good accuracy), then that’s still an error margin of 200g. At 5%, it’s 335g. So it does make sense to build in a margin, or simply to quote conservatively. You might also check this by weighing half a dozen prototypes.

Even if you are making everything yourself, it’s massively going to increase costs to have the kind of QC and process control needed to hit <1% accuracy. It’s probably not going to be economic for an industry like bikes, and in honesty it’s unnecessary, too.

So bearing all that in mind, if my claimed 8kg road bike actually hits the scales at 8.26kg, I can see how that’s happened, without any subterfuge. When my claimed 900g frame weighs in at 1200, that is a single component and a 33% error margin: that’s much harder to justify.

1 Like

Some things I know is that manufactureres publish weight without pedals, in the smallest size and colour (maybe the matt black version),no bottle cages, and so on…

No, like I said, I just wanted to rant :slight_smile: It is also an issue not isolated to my bike, but anyways, I will just go back to riding now.

It is a size Large frame.