Workshop tales, trials and disasters.
Maintenance tips, techniques and myths.
Technical discussion, description and outright lies
You have selected parts very well, however if stiffness is your ultimate goal I would recommend thicker gauge spokes on the rear driveside as a minimum (Sapim Race), or the whole rear wheel. The weigh penalty is about 12g per side. The added stiffness is (I think) noticeable. The weight of this wheelset will be in the 1500-1600g range in either case.
Good luck getting hold of Alchemy hubs .... White Industries T11 would be a good alternative if you can't find the ELF/ORC. Not quite as "cutting edge" from a geometry or bearing placement perspective, but not far behind, and bombproof otherwise. Less expensive as well.
All the best. J
as to the stiffness of rims I'd rate them as follows:
H plus Son Archetype
HED Belgian being the stiffest and best to build and well worth the extra money IMHO
having said that though my wheels are A23's with CKr45 hubs and CXrays 32h and I'm 90kg and the wheels have been fine. I'd love to swap the rims to HED Belgium's though.
I would rate the HED C2 and the Archetype about the same in stiffness - the profile is very similar (read into that what you will), as is the weight.
I run a pair of 32h A23s with Sapim Lasers on Chorus hubs and they've been great as well. Stiff enough for my 82kgs, and around 1630g, still light.
I have a pair of A23 24h front/28h rear demos with DT Aerolite spokes (1500g), and I can tell that they are not quite as stiff as the 32h, but they still feel snappy enough.
But I have a pair of 24/28 Archetypes sitting in my build queue earmarked for myself. I'll use Sapim Race, and they will be stiffer than the 32h Chorus wheelset for sure. About 1600g with White Industries T11.
A wheel's performance is the sum of all it's pieces. Careful spec can make all the difference. The gauge of the spoke is crucial to wheel stiffness.
Velocity A23 is very shallow and light, Pacenti deeper but light (both around 450g), so the ordering there is fine. Archetype is slightly deeper than HED Belgian but a bit heavier so could be stiffer. Kinlin XC-279 is deeper and heavier than all of these and builds into a very stiff wheelset.
just realised that I have a pr of Pacenti TL 28's not the sl23 so discount my last comment.
I built up a pr of Kinlin XD 230's last week to Rotaz MTB disc hubs and the built up nicely.
Next project for myself will be Son28 ISO disc for the front and a CK rear tandem hub to HED Belgian Plus rims 32h with CXrays for the tandem as a set of wheels for Audax rides
Sounds like light tandem wheels.
I'm leaning towards the Heds Plus due to their tubeless compatibility, laced to White industries or campagnolo record hubs. Alchemy isn't available as far as i know. Does anyone know if 32 spokes in the front is an overkill for my weight 88kg. Whenever i climb i can hear the spokes on my fulcrum racing 1's rattle which have 19 spokes upfront and 21 rear.
Last edited by insightt47 on Mon Jan 27, 2014 11:34 pm, edited 1 time in total.
Thats what my wheels feel like theyre doing even when im not sprinting, just pedalling hard for long distances.
I would be going for a minimum 2.0/1.8/2.0 spokes on a Tandem. CX-Rays (or any 1.5mm spoke) will be too light for that application. I fear you will have quite a lot of wheel flex, and might snap spokes. Saving 30g per wheel is not worth the risk in my opinion.
A 24h front with a wide flange hub like the T11 would be OK, but ideally spec a 2.0/1.8/2.0mm spoke to minimise flex.
A 28h front would be bombproof. No need to go as high as 32h, but if you do, 2.0/1.5/2.0mm spokes would be okay if you wanted to shed a little weight.
A 24f/28r build would be a fast/light compromise. 24f/32r or 28f/32r would be a little more bomber (and considering you are planning on racing and training 700k/week on these - that's a wiser choice in my mind).
Not a lot of spokes on those Fulcrums, and light ones at that.
Not many spokes + light spokes + light rims = light but flexy wheels.
You can't circumvent the physics.
Interesting video. Most of this flex is actually due to bearing placement and axle flex. The rim flex (on a shallow rim) would actually be greater at the road.
Bike wheels made with (most) alloy rims deform the most at the road, and this is not greatly transferred to the top of the wheel (opposite to the road contact point - near the brake area). They whole structure is not stiff enough. Think of the wheel as deforming like this "l" where the flex concentrates at the point where the wheel contacts the road. This is especially the case with light rims and or spokes.
Deep alloy rims (nd better quality deep carbon rims) do manage to retain the structure stiffness more, and this is why they can flex up at the pads - the whole system cants left and right "\" or "/".
You are most probably right about CXrays being to light for a tandem but people are winning races on Paketa Tandems fitted with 24h American Classic 420's, so I just want to see how they go.
I once did a time trial on our old Santana Sovereign tandem with a lightweight front wheel. I remember looking down and seeing the wheel flexing from side to side and thinking "oh s**t, this is going to hurt!" but the wheel didn't break.
Currrent wheels are Velocity Aeroheat 40h with DT Swiss 540 hubs and PG spokes. The hubs alone weigh in at 720gr so it's a seriously heavy set of wheels. I want to try something a bit lighter
How about some quality hubs on Hplusson Sl42s. 1850-1900g, built to last, stiff as the proverbial, and aero to boot.
Depending on your total weight and power output, you can choose number of spokes, pattern and gauge. Of course you can choose rim finish as well.
A Ti freehub body would be of long term benefit as well (you probably know where I am heading here!).
On all but the most hilliest of rides, low wheel weight is considerably less of a benefit than improved aerodynamics anyway (as in most bicycle applications - don't believe everything you read on the internet or the glossies!).
Just a thought.
I'm intrigued as to the numbers here. What hubs are you thinking of?
According to the website SL 42's are 615g which leaves only 620 - 670g for hubs and spokes and I'm guessing you'd need 150g to 200g of spokes.
The DT hubs are certainly heavy and I'll believe the 720g geoffs quoted and I have weighed the White Industries MI6 hubs which come in at 200g front and 380g rear (steel freehub), so there is certainly potential for lighter hubs.
Sub 2kg tandem wheels for discs are uncommon without going exotic or coming with weight limits. Rolf and Spinergy come to mind, but I don't care for either, even before price is considered.
I'm not concerned with CX-rays snapping, but flex may be more of an issue. Since geoffs is planning disc brakes, at least the flex won't result in brake rub.
Here are some numbers in response to an email I sent out to wheel builders asking to build me a stiffer wheel.
For a rim:
6/10 Hed c2
3/10 Pacenti sl23
1/10 H PLus Son Archetype
For a hub:
8/10 White industries
1/10 Chris King
6/10 a mix of cx-rays on the front and race spokes on the rear
4/10 a mix of dt-aerolite on the front and dt-comp on the rear
Its important to note that I mentioned i wanted to run a tubeless setup so if i hadn't the H Plus Son Archetype probably would have recieved more votes. Also nearly all the builders recommended Alchemy hubs over White Industries but since they're not available white industries was recommended as an alternative.
I did assume White Industries T11 hubs due to the discussion regarding the AC 420s (I would certainly not use anything less - you want a good strong flange, and Ti freehub for tandem loads), so not a disc hubset. 28h front, Laser Spokes. 32h rear, Race Spokes. Brass nipples all around. 1887g using my average measured weight for SL42s (602g).
Using White Industries MI6 would result in a 2113g wheelset (with the standard steel freehub). A Ti freehub could be specced to save a few grams.
The spokes is a "you say Tomater, I say Tomato" argument. Seems everyone is speccing you the same in that space, just aligning with their preferred vendor.
I am surprised that the Pacenti has not gotten more votes, as it is "the fashion" right now. Supply is difficult, so maybe that's why the HEDs are high on the list.
I would agree, if the tubeless requirement was relaxed, the Archetype would feature much higher. They are well finished, extremely strong, and a known entity. Not expensive either.
T11's are for 130mm spacing. Most tandems are 145mmm these days so the choice of quality hubs is limited to CK, White Ind, DTSwiss. I would like a Paketa that uses 130mm hubs but I haven't saved up the $12k for the frame I want let alone the parts
I've built up quite a few wheels now using the Chris King hubs and everyone just can't believe how smooth the bearings are. I also have the full CK tool set as I have been using CK hubs for 10+ years on our old tandem. The hub is still going strong with no bearing problems and the SS ringdrive still in good condition.
The main problem with CK tandem hubs is that they cost nearly $500 for the rear hub vs $270 for the White Industries tandem hub.
Insight47 - I have no idea why whoever you asked rated the CK as 1/10 and the Whiteind as 8/10 as the CK hubs have the flanges further apart which would build an ever so slightly stiffer wheel. I would doubt that anyone would be able to pick the difference just like you wouldn't know if your tyres have a extra 1 psi in them.
I have rebuilt a few of the Fulcrum 1's. The main problem with them is if you have ridden them a few times in the rain the aluminium nipples corrode and they tend to break when truing the wheel.
haha not rated, that was the number of people who "recommended" that particular hub for the build i asked for
You forgot about Royce... http://www.royceuk.co.uk/Hubs/
Ours is not to reason why...merely to point and giggle
Who is online
Users browsing this forum: No registered users