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Guys at Just Riding Along reckon it will be good as rim is strong, but I'm getting cold feet and may stick with Super Comps.
These are for XC riding to get a good profile on some big tyres.
Not seen too much on these rims on STW; they are 35 mm wide (28 mm internal) and weight 530 g or so -- 70 more than Flows. And way wider and stronger. And cheaper.
And they come in red.
I've got 29" P35s on Super Comps, on a Hope SS / 135 F hub combo. They've taken a few knocks and they're pretty much dead-straight, seem like pretty tough wheels. If it's for a 26" wheel (guessed from the weight) I'd trust JRAs opinions, revs should be fine.
They're great rims that do wonders for the tyre profile but don't go too low PSI as they don't seem as hard atthe edges as some rims, no real issues tho.
Thanks Jameso, yes, for 26er wheels.
What tyres to do you run on yours? I'm interested in the 135 mm front hub wheel and hope to move on to that when I've saved up enough for a Jones.
What is the point of using Revs (or Supercomps) with those? What are you hoping to gain?
Ardent 2.4 EXO, sometimes with a 2.25 LUST rear in the summer. Purgatory 2.2 2-bliss F+R at the moment (12-13psi on crusty snow / ice worked well over last few days). Sealed the rims easily with a few layers of insulation tape.
Perfect wheels for a Jones.
I don't do big drops, so I can lose some weight and go with a lighter spoke.
These are for a rigid bike so bigger tyres are better, and tyres come up huge on these rims.
2.4 Rocket Rons on these rims are massive.
so I can lose some weight
Get some lighter rims then.
Get some lighter rims then
With respect, not great advice. OP's reason for this combo is spot on ime. But a lot of people still think lighter rims are better rims, perhaps, if you like 45psi in your tyres and think 150g saved will really make you faster overall.
rev likely fine but if you are concerned then comps won't make the wheels noticeably heavier.
think 150g saved will really make you faster overall.
Well if 150g saved won't make you faster, then neither will 80g saved!
I just don't see the point in saving weight on spokes for this sort of wheel - maybe on superlight ones, where you're trying to save every gram, but on these you'll only notice the difference in the decreased stiffness, and in your wallet.
I have tried building wheels with Sapim Leader spokes (same as DTswiss rev's) and I found they twisted a little when tensioning and truing. This meant stress relieving always through the wheel out a bit. Not by much only to about 0.5mm radially and latterally on a 700c rim but since I always aim for roundess and trueness of less than 0.2mm this was not accpetable to me. Given the width of the rim proposed they might be fine but it all depends on what you consider and striaght and round wheel. My definition is a bit stricter than most wheel manufacturers it seems. Also 2.0/1.5/2.0mm spokes are fine (in theory) on the front and for the non drive side rear they should be used on the drive side rear.
I would stick to comps as the wheel will be much stronger. Also I ride rims that are much narrower (17mm internal) and never have any problems with the wheels bashing them around thetford forest and local trials which get bumpy.
Nowt wrong with velocity rims though from what I have heard.
Well if 150g saved won't make you faster, then neither will 80g saved!
You're right. My point though is that if you gain weight and width on a rim there are advantages that are worth the weight gain for some riders - technical trails, rigid bikes, etc.
But also if you have 2 parts that do the same thing equally well, you can justify the cost or don't really care about it and safety isn't affected (Comps vs Super Comps in my case), choose the lighter part. No-one wants a bike to be heavier for no good reason.
So to save on spokes to offset rim width gain makes sense. To save 150g or so on the rims but end up on 17mm wide rims that need much higher pressures and give a poorer tyre profile for 2.3-2.4s, well that makes no sense to me. P35s are at one extreme end really, but it's the end of things I'd want for a rigid bike.
But also if you have 2 parts that do the same thing equally well, you can justify the cost or don't really care about it and safety isn't affected (Comps vs Super Comps in my case)
But the Super Comps will make the wheel less stiff - and therefore less strong - so they don't do the same thing equally well. Seems a silly small amount of weight to save given the difference in performance on what presumably aren't race wheels. You'll never notice the difference in weight, but you might notice the decreased stiffness.
With apologies for a OT diversion, and I don't build wheels so I could be wrong, but doesn't wheel stiffness come from spoke tension (and triangulation) more than spoke thickness, assuming both spokes are capable of being tensioned as much as you need to? A spoke on it's own has little stiffness and any gain x 32 still isn't a lot in face of the side-forces on a bike wheel.
I will say that these wheels are super-stiff and fitted to a bike where you'd notice it if they weren't. Stiffer than my 26" AM XTs, DT Tricons etc.
Had to nip out and missed all the action.
What rocked my (slightly lame) world was this page on rolling resistance from schwalbe:
http://www.schwalbetires.com/tech_info/rolling_resistance
Basically, unless out and out acceleration is your aim (as it is to a racer), a wider tyre (and hence a wider rim) makes for a more efficient wheel, i.e. one with LESS rolling resistance:
from that Schwalbe page:
Small diameter tires have a higher rolling resistance at the same tire pressure, because tire deformation is proportionally more important, in other words the tire is "less round". Wider tires roll better than narrow ones. This assertion generally generates skepticism, nevertheless at the same tire pressure a narrow tire deflects more and so deforms more.
But I've just been talking to Jeff Jones too much!
I think I'll go for Super Comps based on all this, BTW. Thanks.
But I've just been talking to Jeff Jones too much!
Not a bad thing, ever ) If he has time to talk, listen.. So what are you going for?
the revs will build a flexier wheel than thicker spokes. HOw much I don't know, and the rim will play a part also.
doesn't wheel stiffness come from spoke tension (and triangulation) more than spoke thickness
No - the spoke tension makes no difference at all to wheel stiffness (we have the agreement of a member of the IoP on this one 😉 )
A spoke on it's own has little stiffness
A spoke has plenty of stiffness - if it didn't your wheels would flop about all over the place. What do you think supports the side forces on a wheel - the rim doesn't do it all on it's own? Just try bending an unbuilt rim, and then try bending a wheel built up with that rim.
P35's are very good, I have some for my jones when it's not in fat front mode. Can't go quite as low pressure as a stans rim without burping though.
Jameso- I can get Ti uno elliptical rings for direct mount on a middleburn 😀
rom that Schwalbe page:
Small diameter tires have a higher rolling resistance at the same tire pressure, because tire deformation is proportionally more important, in other words the tire is "less round". Wider tires roll better than narrow ones. This assertion generally generates skepticism, nevertheless at the same tire pressure a narrow tire deflects more and so deforms more.
Very true. Tyre pressure is by far the dominate term in the equation for rolling resistance along with rider weight and rolling radius. Narrow tyre run higher pressure in general and leads to their lower rolling resitance.
I run 2.0" tyres on my 17 mm rims on one bike and 1.7" on another but this suits my riding and saves weight. I keep my 2.3" tyres for another bike with 19mm internal widths. Really I should stick to 2.1" tyres with that bike.
Narrow tyre run higher pressure in general and leads to their lower rolling resitance.
And harsher ride...
Also true but I manage and like the ride I get from narrow tyres. Also the narrow tyres are on old steel framed MTB's (with lack of tyre clearence) with steel forks. Maybe the flexibilty of the frames helps out here (these two bike are not a stiff as a modern Alu or carbon frames).
what I find interesting is that it's not just a comfort thing with larger tyres.
they roll better -- a larger tyre has less resistance than a smaller one run with the same pressure, if I understand this correctly.
Which all explains why I'll be joining the (front) fat tyre brigade at some point.
Saving up for a ti space frame.
Not that there isn't a trade off with a big tyre, but I think it will be worth it.
It's quite different on mtbs though - grip becomes a factor, and lower pressure = more grip.
Have you looked at the pacenti 28 rims from JRA? I don't know whether to bite the bullet and go with them or get arch EX. They seem a logical progression from the p35 but might not be quite as strong. The guy at JRA says he's given them some DH/rocky use on a big bike and they've been fine tough so might be alright.
The numbers on the pacenti rims look v good imo -- light as the crest (nearly), wide as the flow. But I want something wider -- pacenti are only 2 mm wider internally than the crest (which is 21 mm internal) if I remember right; the p35 is 28 mm internal.
aracer, what's the loP?
More material in the spoke will add some stiffness (proportionately) but - (geek on) - since they have to be under some tension to make a structure that is stable / stiff, way stiffer than the sum of the spokes alone, and more spoke tension than the basic structure needs doesn't make the wheel stiffer, I'd say as long as the spoke can hold the tension you need any stiffness gained from the thicker spoke is simply by adding more material. Not the most effective way to increase stiffness compared to looking a the stucture. You're probably adding a little to something that isn't responsible for the majority of the wheel's stiffness.
So the structure (rim and hub dimension) would make a greater differance then spoke guage in reality, especially if you consider stiffness-to-weight. I'm kind of interested to know by how much, but I expect it's complicated and wheel designs aren't something I know much about, beyond riding them.
I know my 135mm front is waaay stiffer than normal 29er wheels, to the point that I can't understand why sus forks stuck with 100mm front spacing on 29er forks.
(tazzy, make one to fit my 4-bolt cranks and I'll take it but as much as i like the ring shape I'm not buying new cranks too! I do like the midleburns though.. I'm having minor clearance issues as it's effectively a 36T max diameter, the frame's a bit tight there anyway so I have the EBB way fwd with little room for stretch - hows the fit on yours?)
Pacenti's do look good.. a 35mm version would be like a better quality P35.
fit on mine is fine I just moved the EBB a couple of mm to the right on the jones as it still sits flush in the frame and no clearance issues at all.
the integrated proto thingy i'm playin with is blinkin ace, approx 80g lighter and stiffer, so it's sitting on the race ss
normal style 4 bolt ti will be no issues at all, I'll get prices next week so I'll post up a thread as if there's a bit of interest we may be able to get a group buy discount again 😀
Pacenti's do look good.. a 35mm version would be like a better quality P35.
kirk designed the P35 anyway in collaboration with velocity 😀
And for that he's a top bloke ) can't have been easy persuading them to make it, but the P35 is a pricey rim for a sleeved join, the 28s are welded.
All this stuff about rims and wheel weight etc, I've been thinking about how good a carbon 35mm might be, just to test whether I truly don't care about rim weight.. that at the back and a 650b x 3.2" semi-fat front would be fun to try out.
edit,
Count me in for a ti 4-bolt. I was going to shift the EBB over, prob better to mount it in big ring position and move the rear cog over, to move the EBB all the way back. Gotta slam those stays on 29ers. See you can't do that with a posh spiderless ring )
how about a 30mm ENVE carbon one? 440g for the 29er one 😯
Maybe.. but it needs to be at least as wide as the P35.
40mm wide / 500-550g / tubeless ready would be spot on. I would go for those if they made them, trying not to look at the price. I'd probably do some proper research on spokes before getting them built too 🙂
they roll better -- a larger tyre has less resistance than a smaller one run with the same pressure, if I understand this correctly.
I think the wide rim / big tyre is about maximising the air volume too, then you can use less pressure so the tyre can deform to the ground rather than be bounced around. The big rims work for me anyway, but with these bikes the whole is just so much greater than the sum of the parts. A Ti SF? You'll love it.. he was enthusing about the fat front to the point where I have to try one sometime, but I'm still getting used to how good the bike is with the std front.
So the structure (rim and hub dimension) would make a greater differance then spoke guage in reality
Only based on your assumption, which I don't think is correct.
Thicker spokes must make it stronger, the maths to calculate the point of diminishing returns is way beyond us and you are only guessing to suit your belief.
I'd like to see a lot more rims available in the plus 30 mm range, too. I would think bigger rims would catch on, but then I get excited about things like truss forks.
Glad to hear the SF has a thumbs up.
I hope in five years' time I'm not still posting about Jones bikes with real Jones owners. . .
al, why's it not correct? A thicker spoke is stronger, stiffness and weight was the point I was talking about, did you mean stiffer? I may have underestimated how much stiffness a PG spoke adds, not noticed that between similar wheels I've had, but the triangulation from wider hubs does make a difference. Doesn't a good wheel design that's stiff and light start by making the rim and hub support the spokes triangulation best and use as thin / light a spoke as poss?
"I hope in five years' time I'm not still posting about Jones bikes with real Jones owners. . . "
and if you do and I'm still here, ask me why )
Top bike though. Saying much more than that starts me on a roll that after a couple of geek-outs I've had to try to keep to myself. It just comes out in a during- and post-ride grin now.
about Jones bikes with real Jones owners
I don't count, I have a gas pipe version welded by some non bearded asian gentleman rather than a proper Ti one made by a shed dwelling hippy.
Jeff does design a nice frame though and even the plebs version is ace, so a pukka Ti one will be lovely
The Ti's Tai too?
jameso you said
You're probably adding a little to something that isn't responsible for the majority of the wheel's stiffness.
which is what I was taking issue with.
I didn't really see your point about wider hubs, they do for sure make stiffer wheels (I'm not convinced regular wheels aren't stiff enough) but without new standards, discs and freehubs define the flange width.
what's the loP?
I'd say as long as the spoke can hold the tension you need any stiffness gained from the thicker spoke is simply by adding more material. Not the most effective way to increase stiffness compared to looking a the stucture. You're probably adding a little to something that isn't responsible for the majority of the wheel's stiffness.
So the structure (rim and hub dimension) would make a greater differance then spoke guage in reality, especially if you consider stiffness-to-weight.
The effectiveness of gaining stiffness by adding material to the spokes depends on what contribution the spokes make to the stiffness compared to their mass. I get your point about hub dimensions - though as cynic-al points out, there's not a lot you can do with that inside existing standards. The rim dimensions make no difference at all to the triangulation of the spokes - they might make a rim on its own stiff, but a wheel is a lot stiffer than a rim on its own. I'd argue that in terms of stiffness to weight, the spoke gauge actually makes a lot of difference. I can even do some numbers for you: a wheel of PG spokes is 222g, a wheel of revs is 141.5g http://www.dtswiss.com/Products/Components/Spokes.aspx - for your 80g extra weight you get 11% more wheel stiffness http://www.sheldonbrown.com/rinard/wheel/index.htm#7
That sheldon brown link is really helpful aracer.
For this build I'd choose that amount of stiffness over the weight loss.
I'm no mathematician but I do want my wheels as stiff as possible -- with a rigid ride, as I understand it, a 135 mm hub makes a big, big difference. Not that I know from experience, though (yet).
So Jeff said the new Tai frames were better made than his own, right? Not sure how.
JRA just called to say the rims came in; and the spoke decision is Revs.
Why? Not because of stiffness etc but because Super Comps only come in black.
Yep. I'll make sure I specify that in the thread next time. . .
seriously they said they'll be good.
🙂
the spoke decision is Revs.
Why? Not because of stiffness etc but because Super Comps only come in black.
Comps then - they come in silver - as I suggested earlier. Save money, have stiffer wheels.
actually gave comps more of a look than I would have done yesterday, but revs it is.
thanks for the comments.
11pc stiffness gain ain't much, but its a gain, granted. The rinard link suggests it's a deflection diff of a fraction of a mm. 80g ain't much either. Nathans right, color or builder advice is more of a decider ) or cost.
Edit Al I prob don't express my thinking very clearly in writing, I'm not confident I'm right either, if I could figure out what diff flange dimensions made we could compare it to spokes but I wouldn't do it just to score points, simply a point that got me thinking. If you get an answer anywhere I'm interested tho.
80gm is say 7% so 11% gain in stiffness seems good to me.