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PG or DB?

mrfmilomrfmilo Posts: 2,250
edited March 2010 in MTB general
Hi
Basically - PG or DB for DH/FR? What are the benifits?

Thanks
«1

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    DB.

    read the topic in the FAQs or try a search.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • mrfmilomrfmilo Posts: 2,250
    The 'what makes a wheel strong' is interesting.

    I need some new wheels for the new build, am unsure if I should buy some Halo freedoms on Spindoctor hubs, on (I THINK) PG spokes.

    Or handbuild (by me) Spank Stiffys on Spindoctor rear and front Club Roost hubs, DT Swiss DB spokes. This would be the first time building wheels, however I'd like to try and it seems simple enough as long as you don't rush it and follow the steps in guides etc.
    Been reading guides which are helpful.

    Opinions?
  • mrfmilomrfmilo Posts: 2,250
    Actually, the Stiffy rims only come in 32 hole, both those hubs are 36 hole so more hub searching....
  • lawmanlawman Posts: 6,868
    for the love of god, unless you have built wheels before and have done a proper trainig course dont build your own wheels, trust from experience it can go horribly wrong, get a proper shop to do it, because it juts isnt worht doing it yourself to save abit of money.
  • jay12jay12 Posts: 6,306
    if you want wheels built then order some from crc or merlin. as lawman said building your own can go horribily wrong. i would rather save money and my face and use cec or merlin or your LBS
  • mrfmilomrfmilo Posts: 2,250
    lawman wrote:
    for the love of god, unless you have built wheels before and have done a proper trainig course dont build your own wheels, trust from experience it can go horribly wrong, get a proper shop to do it, because it juts isnt worht doing it yourself to save abit of money.

    Well I guess that's what people thought before THEY started building them. I will eventually learn (in the next few years) so why not start early? I might just lace them, and then get the LBS to tension and true them.
  • If anyone wants to learn to build wheels, you can! I taught myself with the help of some instructions from MBUK if I remember rightly. That was 20 years ago, and the 1st set I built were fine. The rear is no more because the hub died, but the front is still on a bike now ridden by a friend.

    I've been building ever since, and whilst there are shops that do a good job, there's plenty that don't. I've destroyed a wheel, it wasn't one I built, it was one that came on a complete bike. Never wrecked one I've built, and I've bent a frame in a head on, the wheel survived without needing a re-true.

    I'm not saying I'm better than anyone else, just making the point that if you learn to do it properly and you take whatever time it takes to get the wheel tight & even you'll build better ones than a lot of shops. Some seem to churn them out too fast, I guess if you're not charging for the build, only the bits then you've got to make your profit.

    On spokes, sonic was making the point a while back that the extra stretch of DB spokes makes for a stronger wheel as the extra give means that the rim isn't subject to such big shock. This makes sense. Spokes are reckoned to be the strongest part of a wheel, which is why often in a failure the spokes don't break, they pull through the rim or crack the hub flange. I've never broken a spoke even when they get damaged by the chain & need replacing.

    If anyone wants to learn I can teach you - I run courses, and if you have a bit of mechanical ability you'll be fine. I'll also build for you, but I do charge for the build, then I can offer an absolute promise that they'll get all the attention it takes with no corners cut.
  • supersonicsupersonic Posts: 82,708 Lives Here
    Yes, with slightly thinner middle sections the load is shifted to more spokes, but the ends, which 99% of the time are the bits that fatigue, are thicker for strength. The butting process increases durability of a spoke too, though all wheels should be stress relieved when built.

    PG spokes have the highest stiffness to weight ratio which is why some pros use them, especially track cyclists. But for durability, a DB spoke matched to your wheel and riding is best (well, a tripple butted most probably ;-))
  • schweizschweiz Posts: 1,644
    edited March 2010
    Why not have a go at building wheels?

    I'd never built one 6 months ago, now I've built three: a 3x rear track hub, a 2x front track hub and a 2x/3x mix powertap hub with bladed spokes.

    Yes it takes time to learn. I started by dismantling and rebuilding an old mountain bike wheel. I did that a couple of times to get the feel for it and then I was away. Yes, bladed spokes were a new challenge, building a dished rear wheel was a bit different from the track hubs and it's taken several hours (10+), but it passed a few dark winter nights.

    Another benefit is that I have a lot more confidence when it comes to truing wheel after an argument with a pot hole/kerb/grid saving even more money. When you're looking at 15 quid a time for a LBS to true a wheel then the outlay in terms of tools is soon recouped.

    I recommend Roger Musson's e-book: http://www.wheelpro.co.uk/wheelbuilding/book.php and some info here about some more exotic spoke lacing patterns for when you've learnt the basics: http://spokeanwheel.110mb.com/lacing.htm

    Take your time, be patient, work logically and you'll be fine.
  • mrfmilomrfmilo Posts: 2,250
    Thanks, I think I'll take a shot at it. :D I can do most thinks on my bike, have built one from scratch and it wasn't challenging IMO, so this is a ''step up''.

    Opinions on Club roost (20mm) front hub, DT DB Spokes, and Sun Ringle mammoth? Then rear is Halo spindoctor, DT DB spokes, on Mammoth rim again? Weight isn't really a problem, it will be on a Norco Torrent (HT) so no shock to absord the landings etc.! , riding DH/FR.

    Thanks!
  • schweizschweiz Posts: 1,644
    I'm really a roadie so can't help on your choices, but one thing I do recommend is using standard DT Brass nipples. In my (limited!) experience. They make wheel building easier. I used DT Proloc nipples on the powertap and 'cos i was being a tart and wanted black spokes and nipples. They have a thread-locking compound in them and the increased friction meant that spoke wind up (where the spoke twists withthe nipple rather the nipple screwing onto the spoke) was a problem that I didn't have with the other wheels.
  • mrfmilomrfmilo Posts: 2,250
    Yeah, when you buy the DT spokes it comes with Brass nipples. Does the book (PDF) that you linked include how to work out spoke length?

    I have seen spoke calculators online, but you need to enter flange measurements etc. How do i find this stuff out? Vernier?
  • schweizschweiz Posts: 1,644
    The book explains it all but if you don't like trigonometry then there's a free spoke length calculator on the wheelpro website too. It just does all the sums for you. I've used it for the 3 wheels I built and found it to be accurate.

    The hub measurements can usually be obtained from the hub manufactures website (HALO definitely have the info on). If not then a vernier calliper it is. Basically you need flange diameter and distance from flange to wheel centre (not hub centre on a rear wheel due to dish!), true rim diameter (either measure using the method in the book or contact the manufacturer) and then decide on spoke lacing pattern although I suggest you start with a standard 3-cross front and rear.

    For peace of mind, once you've got the hub and rim measurements, PM me and I'll stick them into the calculator too. Remember....measure twice, cut (or pay!) once!
  • TorresTorres Posts: 1,266
    mrfmilo wrote:
    Thanks, I think I'll take a shot at it. :D I can do most thinks on my bike, have built one from scratch and it wasn't challenging IMO, so this is a ''step up''.

    Opinions on Club roost (20mm) front hub, DT DB Spokes, and Sun Ringle mammoth? Then rear is Halo spindoctor, DT DB spokes, on Mammoth rim again? Weight isn't really a problem, it will be on a Norco Torrent (HT) so no shock to absord the landings etc.! , riding DH/FR.

    Thanks!
    I've got the spin doctor hubs and the mammoth rims (not on the same wheelset.) Quite like the hubs, especialy their versatility and the noise :twisted: the mammoths aren't bad, they don't set the world on fire, but for 20 notes i can't complain.
    What We Achieve In Life, Echoes In Eternity
  • mrfmilomrfmilo Posts: 2,250
    schweiz Thanks for the help! Will try and get all the measurements today....

    Torres They seem to be pretty tough, but quite heavy (700g +). I might go for Halo SAS rear and Tornado front. Same spokes and hubs. More expensive, but they come in white! :D:lol:
  • mrfmilomrfmilo Posts: 2,250
    For the spindoctor hub I have found this..... http://www.halorims.com/Halo/uploads/techinfo_3.pdf

    That seems to be the measurements, depending on which rim but I don't know what all the stuff stands for!! Can anyone help?

    Thanks :)
  • schweizschweiz Posts: 1,644
    That datasheet gives you the spoke lengths for building the hub into specific HALO rims.

    As you can see there are differences in spoke lengths for 26" rims from the same manufacturer and that's why it's important to use the effective diameter for the rim you are using. How to measure that is in Roger Musson's book.

    The details for the Spin Doctor Hub are on this page:

    http://www.halorims.com/Halo/products-d ... d=HUHASDR2

    with the important stuff to note being:

    Flange Tech:
    C-L 34mm F58mm
    C-R 19mm F58mm

    What that tells you is that the flange diameter is 58mm on both sides and that the distance from wheel centre to the left flange (C-L) is 34mm and the distance from wheel centre to the right flange (C-R) is 19mm. This distance is less than (C-L) because the wheel is dished to take account of the cassette. The rim needs to be centred between the lock nuts, not the flanges.

    Stick this data into the wheel pro spoke calculator along with the rim diameter and it will give you the requred spoke lengths for drive side and non-drive side based on whetever lacing pattern (2x, 3x, 4x) you choose.

    Spoke length is not supercritical +/- a couple of mm will be okay, but it's easier to work with spokes that are a couple of mm too long than too short so if you have the option, then go long.

    Can't find any info on the Club Roost hub. Their website linked from http://www.windwave.co.uk/windwave/KT-T ... d=ycq4nWfw seems to forward to a beauty products website
  • mrfmilomrfmilo Posts: 2,250
    Wow thanks for that! I've decided to go for Halo Tornado on the front and SAS on the rear. :)

    Club toost don't seem to have a website :? Apparently they are great hubs but I'm unsure whether to buy it if they don't even have a website!?

    What are some good front 20mm hubs that can be had (new or used) for £30!?
  • mrfmilomrfmilo Posts: 2,250
    Might get this, can be converted (by screwing out the QR adaptors) to 20mm. http://www.allterraincycles.co.uk/product/115740.html
  • mrfmilomrfmilo Posts: 2,250
    When entering the calculations into the wheelpro calculator it comes up with this:

    ''The rim diameter is smaller than one of the specified hub flanges''

    ??

    This is what I have entered: (for the Spindoctor hub)

    Hub flange diameters
    A. Left 58
    B. Right 58

    Flange distance

    C. Left 34
    D. Right 19



    Rim dia 36
    Rim offset
  • supersonicsupersonic Posts: 82,708 Lives Here
    The rim diameter cannot be 36mm!
  • mrfmilomrfmilo Posts: 2,250
    What is rim diameter?! :oops: :lol: Isn't it the width of the rim?
  • supersonicsupersonic Posts: 82,708 Lives Here
    No lol, the diameter of the hoop! It is know as the Effective Rim Diameter or ERD. You should be able to look it up.
  • mrfmilomrfmilo Posts: 2,250
    Ah! 26 inches? Or does it need to be from inside to inside?
  • supersonicsupersonic Posts: 82,708 Lives Here
    No, not 26 inches - that is a nominal tyre diameter.

    What is the rim? (exactly)
  • mrfmilomrfmilo Posts: 2,250
    Halo SAS rear Tornado Front
  • mrfmilomrfmilo Posts: 2,250
    Oh! That's what ERD means in all the rim listings... :oops: haha

    Thanks!
  • mrfmilomrfmilo Posts: 2,250
    edited March 2010
    OK now I've entered all the info and i believe these are the spoke lengths?:

    ............. Left.....................................................Right
    ............Disc side..............................................Cassette side
    ........R 1x 2x 3x 4x............. R 1x 2x 3x 4x
    36 240.9 242.9 248.4 256.5 266.2........239.3 241.2 246.8 255.0 264
    .7

    Edit: Argh all the numbers have moved in the post now..... anyway a load of numbers have come up, are these the spoke lengths?
  • supersonicsupersonic Posts: 82,708 Lives Here
    You want 3x ie 3 spoke crosses. Lace and build the wheel this way.

    Is it 36 hole?
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