smasha

first, if anyone knows where i can find comparable wheels already built for $160(US) or less, let me know...

otherwise, it's time for me to learn wheel-building. these will be for a commuter bike that carries me (~160lb) and often overloaded pannier bags. i'm running 700x35 marathon tires and BB7 brakes.

i'm looking at 700c rims (leaning towards 36-hole TD17s, but may do A319s). i can get a good deal on XT hubs (with ISO disc brake mounts). add 100 spokes, and i'm looking at about $160 (but i'll spend some $$ on shipping).

i know i won't feel any difference between the XT and deore hubs, but it seems like the XTs are sealed better, so i should be able to forget about them longer.

i ride year round in wellington NZ, lots of rain and maybe some salt spray. if i could find a decent deal on SRAM hubs (or wheels with them) i'd consdier them for the convenience of just swapping out sealed bearings every year or two.

i've got a TM-1 tension meter, and for this i'll probably get a WAG-5 dish tool. i think i'll use a piece of zip-tie and the bike frame for everything else.

am i missing anything? does anyone know what spoke lengths i'd need?

any other thoughts?

thanks...

calstar 

google "bicycle wheel building" or the equivalent, tons of information on how to measure for proper spoke length. If you can get rims, hubs and spokes for $160 that is a great price.

Brian

mrrabbit 

Before you even think about using that TM-1 even ONCE, establish a calibration wheel.

1. Measure 5-6 spokes that provide a variety of reading on the TM-1
2. Label each spoke with their reading using tape - also include the date.
3. Label the entire wheel "YOU TOUCH, YOU DIE!!!" and hang it up where no one can reach it.

...then proceed to go about what you need to do. Check the calibration several times over the first 50 wheels - my experience has been that the TM-1 pretty much settles down for longer periods afterwards.

It's a cheap tool compared to the others - but works quite well when paired with a calibration wheel.

=8-)

smasha

what i can't find are the relevant diameters for the hubs and wheels...

i see that SRAM posts that info on their website where it's easy to find and mavic even has a calculator on their website, but shimano and alex... ???

mrrabbit 

https://www.mrrabbit.net/wheelsbyflemingapplications.php

Spreadsheet....updated sometime everyday...sometimes weekly...grap the EXE as well as it will be needed when working with off-center drilled rims and high-offset drilled rims...

However, as everyone else here will tell you, it really is best to learn to do your own measuring....

Also, search for "wheelsbyfleming" on Youtube and watch the video about spoke thread and nipple behavior so you'll know the importance of testing the threads and nipples you'll use.

=8-)

smasha

^^

i'm eager to measure up everything myself, but i want to get the spokes shipped with the other parts.

the spreadsheet doesn't have the TD17 rims

i'll definitely check out the other resources, too.

fr333zin

I got this book when I started building wheels again last year and can't recommend highly enough. https://www.wheelpro.co.uk/wheelbuilding/book.php also includes details of diy wheel building stand and dishing tool and a link to an online spoke calculator. But the very best advice I can give is to buy this type of spoke wrench called a Spokey https://www.rosebikes.co.uk/article/r...FQHcfAod3zB32Q mine has been invaluable over 25+ years and still going strong.

(I do not mean to suggest that the Wheelpro spoke calculator is better than Mr Rabbit's, only that it exists)

Ah, re-read your comment about TD17 rims. You can usually find the rim ERD on the manufacturer's website or in the blurb on the stockist's website if they are any good. Here's the manufacturer pages for Alex TD17 700c: https://alexrims.com/product_detail.a...=4&cat=4&id=85 ERD 601mm and 26": https://alexrims.com/product_detail.a...=2&cat=2&id=56 ERD 538.8mm

Kimmo

See here as to why you shouldn't consider anything but Shimano for your rear hub.

You should also know that off-centre rims give you more strength for no weight penalty, and as such aren't nearly common enough. Not sure if you can get a bare OCR from anyone but Velocity... an OCR might even be a good idea on the front, if using a disc hub.

mrrabbit 

JensonUSA says 700c ERD = 605

https://www.jensonusa.com/!Acv!f6FJCq.../Alex-TD17-Rim

Universal Cycles say 26" ERD = 544

https://www.universalcycles.com/shopp...2&category=139

Google is your friend...

Call 'em both and ask if they are referencing the top of a standard profile nipple, or the screwdriver flat of a standard profile nipple.

=8-)

fr333zin

Not so - look at the exploded diagram of the Hope Pro 3 Mono (which I prefer to any Shimano) here https://www.hopetech.com/webtop/modul...oRear-Assy.pdf There are several other manufacturers with better hub designs than Shimano and Campag.

Kimmo

That hub appears to have an extra axle bearing, but I can't see how it's doing any good, since the entire freehub body is floating, just like all other non-Shimano cassette hubs. That third bearing seems to only really be doing duty as a spurious third freewheel bearing. Of course, the drawbacks of this design have been countered simply by throwing more metal at the problem.

I repeat, nobody has a better freehub design than Shimano. Because Shimano's is the only true freehub: it features a structural member inside the splined bit that gives you an outboard axle bearing.

fr333zin

Hmmm, no desire to teach you engineering, but it's pretty clear the Hope design has two bearings for the freehub and an outboard axle bearing as well. Total of 5 bearings, all of which are stainless steel close tolerance and sealed. Throwing metal at the problem may be a fair cop, it does weigh 9g more than the Dura-Ace one, which is really a lot and must have a big effect on performance.

I note the structural member in the Shimano design is also a wearing part and relies on the concentricity of the screwthread for alignment. I guess we made our choices for different reasons.

smasha

the TD17 rims have a presta valve-hole... should i switch to presta tubes? or should i ream-out the holes to fit schader valves?

fr333zin

Go with Presta valves, they can withstand more pressure.

Kimmo

I'd like to know what I'm missing here.

What's supporting that outboard 'axle' bearing? As far as I can see it resides in the end of the freehub body, which is only supported by those two smaller bearings. IMO that centre bearing is doing all the work, and will likely fail early.

The weight issue may be academic, but I think it's fair to say Shimano's tech is higher* - they're still offering adjustable bearings (in their unique system that neatly the distributes the load equally) on the new-fangled oversized stuff - who else doesn't give you cartridge bearings these days?

*Adjustable bearings are higher tech than cartridge - they use less metal and involve more engineering. STI may be a dog's breakfast, but Shimano are heavy hitters in bike tech.

smasha

doh! i was looking at really cheap spokes. looks like the build will cost closer to $225 with decent spokes and niples. still, that's about half of what i'd spend locally for deore/a319 wheels (built) and i'm not seeing anything else off-the-shelf that's close. it seems like XT/700c wheels for a commuter bike aren't that popular.

based on the calculators and data that i can find, it looks like a cross-3 lacing will need...
rear - 285.8mm & 287mm
front - 287.4mm & 285.8mm

so i guess i should order 2.0x1.7, 284mm and 286mm...?

smasha

700x35 marathons on a commuter... i only pump 'em up to 80psi.

Kimmo

Schrader valves blow, just use an adapter.

fr333zin

I don't think we are ever going to agree :O) Those bearings need to be adjusted because of the rate they wear at and are a compromise in materials. Cartridge bearings in comparison wear much more slowly and are manufactured to better tolerances in ideal materials. Also they allow a larger diameter and stiffer axle. In both designs remember the freewheel is locked up most of the time under drive - in the Hope design (and others) this spreads the load to the outboard bearing. 'Fail early' is somewhat academic as it will still outlast the comparator cup and cone bearing.

You keep buying Shimano and I'll keep not buying Shimano - we'll both be happy!

Kimmo

If you look at later DA hubs, you'll see there's no reason why cup and cone bearings can't be used on oversized axles.

I'm also extremely dubious about the claim that they aren't made to the same standards. Adjustment isn't about wear; it's just about adjustment given the assembly can be dismantled.

And it can be dismantled because it's designed specifically for a bike hub, and doesn't employ off-the-shelf 'bearings for whatever', the use of which obviously results in using more steel than is strictly necessary.

Shimano is a vast company, with virtually unparalleled R&D resources to develop cycling components to standards only attainable by other such vast companies. The days of boutique backyarders being able to compete in the state of the art are long gone, IMO.

fr333zin

Yep, good point. Shimano have indeed put oversize bearings in later DA. But as I've written elsewhere on these forums, the materials are a compromise. They have to be forged to get the strength needed and soft enough to cut screw threads then case-hardened to be suited to use as a bearing. How much simpler to grind a bearing race in hard stainless which isn't trying to be a structural part. There is nothing special about the loads on bicycle wheels that demands anything other than a deep race ball-bearing to be used. But bearing manufacture is a specialist business needing large machinery investment which is why most of industry buys them in (apart from Chris King in the bike world). What sort of wheel bearings does your car/motorbike run on?

We've already covered the excess materials question - Hope Mono Rear 9g heavier than DA but has 3 additional bearings - does DA freehub run on bearings supported by the axle like Hope does? I can't tell from the schematic but it doesn't look like it.

Yes, Shimano is a vast company making the bulk of components used on mid to low-end bikes. It's impressive that they also maintain a top-end product line like DA. But that doesn't mean DA would be a 'money no object' development, that's not sound business sense. I'm sure Shimano accountants are as shrewd as any, meaning DA specific investment has to be re-couped from its own sales. Hence the incompatibilities between DA Di2 and Ultegra Di2.

BTW I have no connection with Hope, I just like their stuff. But I'm not alone.

Kimmo

Just shooting from the hip here, but I'm pretty sure there's nothing surprising about the existence of Dura-Ace; a company that makes such bulk low to mid-end gear would have a pretty secure profit stream, a given chunk of which would be earmarked for R&D, which DA would get the lion's share of. IMO it's a good bet that Shimano has more funds for R&D than Campy or SRAM... we're talking about a company here that worked out how to make hollow single-piece forgings 20 years ago. Can anyone else do that today? The investment is obviously worth it, since the manufacturing tech gets cheaper (to various extents) and the features trickle down to the more profitable groups. (I'm just guessing here, but it'd seem to make sense to throw all the tech you can at your top group, minimise profit on it to maximise market penetration, and take your profit from the comparitively vast mid range.)

As for Di2 - I reckon you can make an argument that the difference between DA and Ultegra shows that DA is something of a money-no-object group (obviously not entirely) - those are bespoke actuators in DA Di2, prohibitively expensive for Ultegra. In fact, I wouldn't be surprised if DA sometimes made a loss for Shimano, as the tech that goes into it is often brand new and yet to be refined and benefit from economies of scale. Consider the first hollow DA cranks - these were forged in a C section and had the back welded on, and had to be ground smooth. IIRC that only lasted a year before they figured out the magic of doing it in one piece... but it doesn't take a stretch of the imagination to see that costing a bomb.

What, so every threaded cone is metallurgically inferior to its cartridge counterpart?
A - doubt it's necessarily the case.
B - don't care; as you say, bike wheels aren't subject to huge loads. Cup and cone bearings have proven fine for a century; it seems to me, cartridge bearings only happened because they're cheap, and they allow any Tom, Dick or Harry to make hubs.
C - I have NFI how my car's tapered rollers (I guess) are relevant. Cars are a whole other ball game, played in the main on a relatively low-rent field since you're paying for >100x the amount of material and complexity in a car. A car made to the standard of a decent bike is a supercar. Porsche made an engine once filled with needle rollers instead of sleeve bearings. Relevant? Probably not.

No, Shimano hubs (except for the DA experiment where they copied everyone else for a year) use the hubshell to support the freehub bearings, via the core of the cassette body, the end of which holds the axle bearing race. This design is exactly what makes Shimano hubs inherently superior, speculation about the level of their tech aside.


Also, I don't know what you're worried about vis-a-vis concentricity; it's not a screw-on hub. The cassette body is located both by those splines, and that threaded sleeve. You might say the thread for it in the hubshell could be off-center, but IMO such a thread isn't subject to the same inaccuracies that plague the much larger external thread on screw-on hubs, and besides, the splines do most of the work locating the cassette body while the sleeve merely holds it against the face around them. Torque on the cassette body would serve to evenly take up any clearance around the splines.

fr333zin

Ha ha, must say you are a pleasure to debate with, Kimmo :O)

A. Yes I'm asserting that cones are metallurgically inferior to a good cartridge bearing.
B. Tom, Dick and Harry have managed to get pretty good at building hubs that compete with DA.
C. The point is they aren't cup and cone and will have been bought in from a specialist OEM.

Well the concentricity point is about Item 10 in the diagram, if the thread is formed off centre either on that part or internal to the hub it results in run out at the bearing end.

However, I think we have established some facts:

1. You REALLY like Dura-Ace
2. I REALLY like Hope
3. We don't agree with each other

Thanks for the chat, and I am going to move on now. I leave you the honour of the final post on the subject if you wish!