38mm v 50mm depth rims

backo
backo Posts: 167
edited August 2013 in Road buying advice
Afternoon...wondering if someone could provide some advice on what rim depth I should go for.

Looking to purchase some carbon tubs (never owned tubs and really keen to see what they are like)

Have priced up identical rims, spokes, hubs with very little difference in price...the only difference being the depth in rim. The 38mm weigh 1200g and the 50mm weigh 1270g

I weigh 85kg and the wheels will be used as my best set. Im considering getting into racing next season but like long rides...more hills the better. I have tried TTs this summer but whilst I dont mind TTs..they arent really my cup of tea.
My initial preference is the 38mms as they are lighter for accelerating and climbing but the difference in weight between the two seems minimal.

Will the 50mm be noticeably better aero wise when up to cruising speed?
Will the 38mm being noticeable quicker out of the blocks and climbing hills?
Will there be any difference in stiffness?

Would appreciate anyones thoughts who has experience of riding these types of wheels.

Comments

  • mfin
    mfin Posts: 6,729
    Which make and model are they at those weights?
  • ugo.santalucia
    ugo.santalucia Posts: 28,301
    Generally speaking, 38 will give you better handling and will be stiff enough at your weight if you stick a 24 H at the rear.
    left the forum March 2023
  • denniskwok
    denniskwok Posts: 339
    I had the same quandary as you. In the end I went for a 38mm front and 50mm rear.
  • backo
    backo Posts: 167
    never thought of handling..cheers ugo..they will be 20H/24H so I would expect them to fine in terms of flexing...currently have fulcrums 3 and do note the front with 16H can flex when climbing hard...would hope both the 38mm and 50mm will be better than the fulcrums in this respect.

    38mm front/50mm rear....even more food for thought :(:lol:

    they are handbuilts mfin, gigantex rims with cx ray spokes

    so no real difference in aero between the two?

    Think Im swaying towards the 38mm
  • huuregeil
    huuregeil Posts: 780
    Go with the 50mms. Stiffer (particularly given you're a bigger chap), slight aero benefit, difference in weight is negligible, handling differences are a non-issue (particularly given you're a bigger chap). I use my gigantex 50mms regularly in both road races and TTs, great wheels!

    PS If you're not racing, mind, these are overkill. Just long hilly rides... there are better options.
  • pitchshifter
    pitchshifter Posts: 1,476
    Anyone know where you can buy Gigantex tubular rims on their own?
  • ugo.santalucia
    ugo.santalucia Posts: 28,301
    Anyone know where you can buy Gigantex tubular rims on their own?

    Planet X carbon rims are Gigantex... but they only have 50 mm or deeper. Also, they are drilled for internal nipples... nothing wrong with that but just so that you know.
    With your Andy Schleck-like figure you can safely go for the 16/24 combination they offer and at 99 quid a rim they can be beaten... :wink:
    If you want the 38mm, then BHS in the USA is the place to look
    left the forum March 2023
  • pitchshifter
    pitchshifter Posts: 1,476
    They're Gigantex are they? Awesome. I am slowing warming to the tubular idea the more I read..
  • ugo.santalucia
    ugo.santalucia Posts: 28,301
    They're Gigantex are they? Awesome. I am slowing warming to the tubular idea the more I read..

    They are indeed Gigantex, I wrote a piece about them on my blog

    http://paolocoppo.drupalgardens.com/con ... ims-12-faq
    left the forum March 2023
  • cycleclinic
    cycleclinic Posts: 6,865
    The gigantex I stock are drilled for normal nipples but again are 50mm deep tubulars. Gigantex do indeed do 38mm deep tubulars too but these are not imported by the distributor.

    Plantet X prices are pretty cheap.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.