Which Gears For NuVinci With Shift Kit?

Discussion in 'Frame Mounted Engines' started by 5-7HEAVEN, Aug 6, 2010.

  1. 5-7HEAVEN

    5-7HEAVEN Guest

    My friend Rick runs a Staton chain-drive box and NuVinci hub on his bike, using a GP460 engine he borrowed from me. I'm easily impressed, so I bought a NuVinci hub from Staton for a great price at $229!

    Is anyone running a NuVinci hub through their shift kit?

    What size sprockets are you running at the NV hub, chainrings, and drive sprockets? What are your gear ratios?
     

  2. 5-7HEAVEN

    5-7HEAVEN Guest

    Gear Ratios

    Well, if ya want something done...DIY.:jester:


    Using Staton's data on his NV/chain drive, Dave starts with a gearbox having 18.75:1 gearing. Mounted outside his gearbox are his drive sprockets, ranging from 16-tooth to 22-tooth cogs. There's a 27-tooth driven sprocket mount on his NV hub. Gear ratio varies from 23:1 to 31.64:1 before entering the hub. The NuVinci ratios vary infinitely from 350%(3.5:1) to 50%(.50:1). Therefore, final drive ratios can vary from a super low of 110.74:1 for a 16t/27t combination and 3.5:1, to an 11.51:1 with a 22t/27t and the highest .50:1 NV ratio.

    I'm using this NuVinci hub without the Staton 18.75:1 gearbox. Instead, I'm running a frame-mounted Tanaka engine thru a Scooterguy mount and shift kit, then to the NV hub. I'll be using an 11-tooth drive sprocket linked to a 63-tooth chainring, for primary gearing of 5.727:1. With a 5:1 pocketbike gearbox, ratio increases to 28.64:1. The secondary chainring has 22 teeth, which connects to the 16-tooth NuVinci hub sprocket(I chose this 16t gear for ease of pedalling without the engine). This 22t/16t ratio is .73:1; multiply that by 28.64:1 and you have 20.83:1 gearing before entering the hub. Close enough, because of the NV's gearing.

    With the NuVinci's gears of 3.5:1, low gear is 72.9:1 for my 11t/63t and 22t/16t gearing. Highest .5 NV gear decreases to 10.4:1. Unuseable, which is good; according to NV specs, the hub normally rotates counter-clockwise, but kicks CLOCKWISE at .5:1 ratio.(probably momentarily, which wreaks havoc on the hub's torsion bars and the NV axle). This high ratio guarantees that the lowest .5:1 gear ratio will never be utilized in my application.

    Looking at Staton's NuVinci web page, Dave uses 18.75:1 gearbox, 6000rpm engine checkpoint at the hub's 1.75:1 and .5:1 ratio for each gear selection. For instance, with a:

    16t/27t combination, at 6,000rpm, speeds of 8.5mph @ 1.75:1(total 55.37:1) and 29.6mph at the .5:1(15.82:1).
    17t/27t " " " 9mph @ 52.11:1 and 31.4mph (14.89:1) " "
    18t/27t " " " 9.5mph @ 49.22 and 33.2mph(14.06:1)
    20t/27t " " " 10.9mph @ 44.3:1 and 38mph(12.66:1)
    22t/27t " " " 11.6mph @ 40.27:1 and 40.7mph(11.5:1)

    http://www.staton-inc.com/Details.asp?ProductID=3274

    In comparison, my combination of gears amount to 72.9:1, including the NV's 3.5 gear. Instead of matching Staton's gearbox, I'm comparing this with my present combination with 8-speed cassette of 32t/26t/21t/18t/16t/14t/12t/11t gears.

    32t = 28.64 X 32t/22t = 41.65:1. Since 72.9 = 28.64 X (16t/22t) X 3.5(NV's top gear), then at NV's 2:1(200%), it's a gearing equivalent to a 32-tooth cassette first gear.
    26t = 33.84:1, or NV's 162%
    21t = 27.33:1, or NV's 131%
    18t = 23.43:1, or NV's 112%
    16t = 20.83:1, or NV's 100%
    14t = 18.22:1, or NV's 87%
    12t = 15.62:1, or NV's 75%
    11t = 14.32:1, or NV's 69%

    With a range of 69% to 200%, that's all I need. The NuVinci has a range of 50% to 350%.

    I'm in the same ballpark as using my present 8-speed cassette, if I use my existing gearing, the NuVinci hub and its 16-tooth sprocket!:detective:
     
    Last edited by a moderator: Aug 7, 2010
  3. spad4me

    spad4me Member

    Thank you for the information.
    I want to run the almost same setup on a recycled full suspension bicycle I just revived.
    Have a very good day!

    I was looking at the SDRAM DUAL drive hub from endless sphere.
    I like the nuvinci hub a lot.MORE.
    I have had so many stolen motorized bicycles lately I stopped using happytimes.
    Free racing bicycle engines for all is bull.
    The gp460 and others are safe.LOL
     
    Last edited: Aug 9, 2010
  4. 5-7HEAVEN

    5-7HEAVEN Guest

    spad4me, I'm glad you got something out of my research.

    My friend Rick is having an awesome time with the 460/NuVinci.

    I'm having a "design change" as we speak.:idea:

    The NuVinci hub will probably go into a medium-sized 29" bike frame. Rear wheel will be a 36-hole Mavic rim and 9-gauge spokes.

    At any speed, I have a hunch the 29er should handle bad paved roads easier and go 4mph faster throughout the hub's range. Of course, I don't have anything to start my 29er project except this epiphany(vision) I just had.:jester:

    My research data will change because of the difference in wheel diameter. However, methinks I'll still be in the ballpark.:detective:
     
    Last edited by a moderator: Aug 9, 2010
  5. spad4me

    spad4me Member

    I see you are going to use superstrong a rim and spoke combination.
    I pm ed the wheelmaster for prices as I have NO local competent bicyble shops, only wallmart.
    I called staton because I could not use his website. He removed all possible ways to buy a pre laced wheel from him.

    Also a new warning that NO warrany for any type of motorized bicycle.
    Pedal power only for warranty.
     
  6. Ghost0

    Ghost0 Guest

    With a 26 inch wheel I have been told by a few customers with the Shift Kit that the 18 tooth is the way to go. With that information I am sure that the correct one could be calculated. Maybe a 20 or a 21 for a 29 inch.
     
  7. 5-7HEAVEN

    5-7HEAVEN Guest

    Yes, I've noticed that Staton isn't advertising wheels.

    If I supply rim and hub, The Wheelmaster quoted me $180 to build it with any size spoke to 9g.

    These are the rims I might use:

    http://www.amazon.com/SunRingle-Sun-Rhyno-Silver-Presta/dp/B001CJZ6VG/ref=pd_ecc_rvi_cart_1

    or: http://www.bikebling.com/ProductDetails.asp?ProductCode=Mavic08-TN-719-29er
     
    Last edited by a moderator: Aug 13, 2010
  8. spad4me

    spad4me Member

    Ghost0 your recommendations are in the preferred range with the final sprocket size
    . Thank you
    I will of course use sick bike parts in my build as they do not seem to fail .
     
  9. Hawaii_Ed

    Hawaii_Ed Member

    that'll be a slick setup. Good analysis on the gearing!
     
  10. 5-7HEAVEN

    5-7HEAVEN Guest

    Thanks for tips, guys.

    I'm grateful that Steve(detonator Tuning) shared his build with Scooterguy drive and GP460 engine. I'll be following that thread.

    The NuVinci hub arrived. I'll wait until I find a 29"frame before looking for rims and tires. Wheels might be in the deal.:idea:
     
  11. spad4me

    spad4me Member

    Detonator Tuning still has some scooterguy engine mounts for sale.
     
  12. 5-7HEAVEN

    5-7HEAVEN Guest

    Thanks, spad
     
  13. Rodney9872003

    Rodney9872003 New Member

    Need some help please,
    I am building a motorized bicycle using the Honda GXH50 engine with the EZ Qmatic drive on it. Then I have also purchased the Shift Kit from Sick Bike Parts LLC, The other big purchaces was the Nuvinci Developer kit, Now the big question is where do I begin with what size chainring to use and what size cog for the Nuvinci? This is getting so confusing to me, think once I get all this to happen properly will have a good thing. Help me out please
     
  14. bigoilbob

    bigoilbob Member

    Rodney, IM going 2B accused of only talking about 1 thing on this forum, but 2 bad. The NVDK is something I know about, and IM the only person I know who has successfully deployed it 4 an MAB app. There must B more, but I looked, unsuccessfully.

    3 biggies.
    First, steady INPUT torque should be limited to their recommended 48 ft*lb. I say this 'cos my app pushes this limit and has worked flawlessly 4 >2 years, and others who cratered theirs. almost certainly over torqued. They didn't volunteer this, but it seemed obvious 2 me from description of their builds. This torque limit will be hard (but not impossible) to stay under, with your other drive train components.
    Second, you need a strong, STEADY, 12 (minimum) volt/5-6 amp power source to shift up with. Otherwise your electronics will cycle off every time U hit a bump, and you will be stuck in low until you reboot (power off, then back on). I made a charge system from scratch - proud of it but lots of work.
    Third, your controller has Mickey Mouse circuit board anchoring. The jiggling will tear it loose at the plug in points FU don't gorilla glue them in place. Search kcvale posts from 2-3 years ago, as he took some good pix and gave some good advice on this.
    Second post on this today, coincidentally. As I said earlier, I only think a NVDK equipped MAB can work 4 (1) lower powered 20" powered wheel apps like mine, or (2) as jackshafts, spinning faster with less torque.

    FUR still interested, check my vids from last year. Overlong, but fairly explanatory and complete.

    G'luck!
     
  15. Rodney9872003

    Rodney9872003 New Member

    Thank you very much, I also be really interested in the power supply you made as well. I been trying to figure out a good power source that is not some ugly monster deal, Want to be running good and looking good if you know what I mean? lol. I will search the posts as you said as well, I really want to make this a nice reliable good looking bike.
     
  16. bigoilbob

    bigoilbob Member

    @Rodney My charging system is not gorgeous. IM sure U can do better. Check my vids and U will agree. But I put lots of time and dead ends into my components and how I combined them, and they have worked well 4 me 4 awhile now. I think I linked 2 most of the suppliers in my lengthy build explanation, but happy 2 repost any links U can not find.

    Editorial comment; Even without the need for 50-60 watts to shift a NVDK, many MAB riders have expressed the need 4 more/bigger lights. Neither the "Wonderful Creations" or other mag draws, nor the Mickey Mouse friction gens, nor even hub gens, will meet these needs. So, why more kits don't include REAL charging systems? Why have a gas engine bike that needs charging?
     
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