trying to work out how much my new rims weigh

WTB dont list them on their website

now if the weights for narrower rims they do list look like this

i19 507g
i23 583g
i25 597g
i29 ???

so is this right? 666g or so

flows here i come!

666g the rim of the beast?

More seriously, having heard stories of Mk3 Stans cracking around the spokes I’d be looking at EX511 rather than Flows if you want strength

Your graph suggests more of a curve, so the i29 may be lighter than you suggested.

yeah i know the stans rep & I know a stans rep, id be right on him if i had problems

let me go back to excel…

(critique my graph)

can’t bear a graph with axes that don’t run to zero – even in this case where zero’s meaningless

My set of i25 29ers on pro2evo doesn’t feel noticeably heavier than my set of Mk2 FlowEXs on same. That’s Frequency Teams, mind- not sure about the STs. For that matter my i35’s on pro4 aren’t particularly heavy either …

critique my graph

I think you mean criticize. Critique is a noun, and a French one at that.

And did you do your graph in 1982?

not sure about the STs

The ST rims are budget and often appear on OE wheels. I don’t think there is anything wrong with them but they are a little hefty. I’d put 20p on Kimbers rims being around 625g each so I can see the temptation to swap for 100g lighter each Flows

Odd numbers on a vertical axis? What the hell is wrong with you?

I think you mean criticize. Critique is a noun, and a French one at that.

It’s originally French, but it’s long been naturalised and used as a verb.

As I say to my son, if you’re going to be pedantic, you need to check two things, and the first is that you’re actually right 😉

So I have been lookign at a pair of i29 KOM rims as hey come in at a claimed weight of 499g each, which seems pretty light for a wide 29 rim. However im concerned that they may be made of cheese? Any experience of them at all? WTB class them as “Trail/AM/Enduro” for whatever thats worth…..

In use KOM i25s in 650 size on my Marley. They’re spot on. No troubles whatsoever. The wheels have never been touched with a spoke key since I built them.

I’d not hesitate to buy another KOM rim.

Critique your pwnage.

Id personally run the axis so weight is on y.

If I get bored I’ll see if I can model the trend algebraically for you and extrapolate. In fact my A Level class can do that Monday morning as a starter

Be interested in the real answer to see how accurate we get it.

Personally I’m better qualified in engineering than statistics, so I’d be teaching the A-level class to be more than a little bit sceptical about using a three-point data set to derive a trend curve which, if it adheres to those points, is going to predict that no matter how wide you make a rim it’s never going to weigh more than about 620g 😉

KOMs are pretty soft but they’re still good for what they are. Kind of like an early Stans rim, you have to make the call on what’s actually tough enough. For me they’d be tough enough to use but not tough enough to last, which is alright as long as you know in advance.

They’re pretty much giving Frequency i25s away at CRC now. The weight difference between the Frequency i25 and i29 is only 21g though for 29er so that was a no brainer for me.

quick google at the Asym i29s in 29″ that i have and found this in about 2 seconds:

26″ 538 35mm TBA 559x35c 32 / 4.5mm
27.5″ 563 29mm 538g 584x29c 32 / 4.5mm
27.5″ 563 35mm 570g 584x35c 32 / 4.5mm
29″ 599 29mm 583g 622x29c 32 / 4.5mm
29″ 599 35mm 612g 622x35c 32 / 4.5mm

Can’t imagine there’s too much difference to that

Personally I’m better qualified in engineering than statistics, so I’d be teaching the A-level class to be more than a little bit sceptical about using a three-point data set to derive a trend curve which, if it adheres to those points, is going to predict that no matter how wide you make a rim it’s never going to weigh more than about 620g

Me too, MEng in Mechanical from Nottingham. I’ll also be asking them to consider limits to their model. This week we used differentiation to complete a packaging problem and one of them was arguing -4.325… was an optimum answer. He didnt realise he was talking in cm lol

chilled76 – Member
Id personally run the axis so weight is on y.

If I get bored I’ll see if I can model the trend algebraically for you and extrapolate. In fact my A Level class can do that Monday morning as a starter

Be interested in the real answer to see how accurate we get it.

I actually work with several postdoctoral mathematicians who could pop out an answer for me in a few mins !

quick google at the Asym i29s in 29″ that i have and found this in about 2 seconds:

26″ 538 35mm TBA 559x35c 32 / 4.5mm
27.5″ 563 29mm 538g 584x29c 32 / 4.5mm
27.5″ 563 35mm 570g 584x35c 32 / 4.5mm
29″ 599 29mm 583g 622x29c 32 / 4.5mm
29″ 599 35mm 612g 622x35c 32 / 4.5mm

Can’t imagine there’s too much difference to that

Considered that but
1) the at rims are quite different in cross section
Vs asym

Also 29 at i25 is about 45g heavier than frequency i25 and but also with non linear increase as you vary rim width

There’s also the issue of manufacture weights being BS !

CRC had the 29er STi29 rims at 580g I think, I was looking a while back and not sure if they’re still for sale there.

On a similar note I’d be curious to know the difference between ST and STp rims? STp’s are specced on an S-150 I’m looking at and would like to know the weight. Not expecting them to be light though! Half tempted to swap out for a set of flow’s straight away.

*597g, unless that’s a copy/paste from the i25 rims.

http://www.chainreactioncycles.com/wtb-st-i-29-mtb-rim/rp-prod151670

Yeah that’s the same weight as the i25 so colour me sceptical