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What exactly is a "front-end accessory drive"? Wikipedia doesn't seem to have a description.
I would like to remove the Introduction Tag, but I will do so only if two other contributers agree that it is no longer necessary. —Preceding unsigned comment added by 216.79.193.52 ( talk) 21:54, 12 November 2009 (UTC)
To me, this article reads like an advert. The whole text praises the benefits of the drive, and there are no real contrasting viewpoints. I'm rather new to wiki, so I won't put an Template:Advert warning on it, but it does not seem to keep a neutral point of view. 130.227.121.251 ( talk) 12:47, 2 December 2009 (UTC)
I understand your concern, but in my research for this article I found few critical receptions. The bicycle hub has a narrower gear range than certain mountain bike derailleurs, but this was the only negetive on a long list of its characteristics. The earliest version was an ad, however, co it may still seem self-serving. If you have any specific feedback on a particular phrase, I welcome it. —Preceding unsigned comment added by Kevandegrift ( talk • contribs) 21:25, 10 December 2009 (UTC)
I agree - reads like an advert. NuVinci's unwillingness to publish efficiencies and endless talk of 'overall efficiency' suggests these must be way wores than a hub gear. —Preceding unsigned comment added by 207.245.198.135 ( talk) 15:35, 14 June 2010 (UTC)
100% agree... it looks like an advert, and fails to mention other similar technologies (i.e. Torotrack) and deficiencies (like a purported weight of 11 pounds) —Preceding unsigned comment added by Au leon ( talk • contribs) 06:25, 30 June 2010 (UTC)
Still reads like an ad. Ok, it mentions the heavy weight but in the next sentence it qualifies it ("does not need to be lightweight"). moreover there are hub drives with a broader range (rohloff). --
62.178.0.147 (
talk) 23:36, 9 April 2011 (UTC)
It does read like an advert, and seeing there is broad agreement, I am adding the template as such. Andrew B ( talk) 03:58, 5 September 2013 (UTC)
I am a bicycle rider and was interested to know what the efficiency (input : output power transfer) of the NuVinci drive was. A chain ring to sprocket drive typically has 97 % efficiency, much higher than gears and a drive shaft. Since a chain ring drives a sprocket on the NuVinci casing, its efficiency is immediately going to be less than 97 %.
This issue is fudged by comparing this large disadvantage with other unrelated advantages. I believe the entire article needs to be rewritten so that the advantages and disadvantages are clearly distinguished. Then people can weigh up for themselves whether certain advantages are desirable even in the face of the disadvantages. Since I am not a mechanical engineer, I don't have the knowledge to do this rewrite. —Preceding unsigned comment added by Hfinger ( talk • contribs) 11:56, 27 December 2009 (UTC)
I come from the automotive world, so I think I can shed a little light on some of this. "Front end accessory drive", also known as a "Front engine accessory drive" is more commonly referred to by it's acronym in automotive, FEAD, pronounced fee-add. Basically, it is the accessory system that (usually) hangs off the front of your engine, is driven by a belt, and may include the alternator, water pump, power steering pump, AC compressor, etc. There have been a laundry list of attempts over the years to apply CVTs to FEADs (SAE paper 970007 is one example) without success. There's a need, but the combination of circumstances has not been right yet.
With respect to efficiency, CVT suppliers to the automotive world (mainly Jatco, Bosch VDT & LuK) seldom ever quote numbers for two reasons: 1)While its relatively straightforward to measure efficiency in a conventional transmission in each gear, and those numbers have a relatively small dependence on load, whereas the equivalent measurement in a CVT is a 3-D surface that does have a significant load dependency and 2)automotive CVTs usually have terrible straight up efficiency (67% for belt CVTs in SAE paper 2007-01-1457, as opposed to 90+% for a manual trans). In our world, CVTs more than make up for the efficiency loss by making the overall powertrain more efficient - see Nissan cars & SUVs using that 67% efficient belt CVT, their acceleration & EPA mileage are usually among best-in-class. Does the same hold true for a bicycle's "engine" and this CVT? Can't answer that one, but you would think it has to be more efficient than a belt CVT to even be sold on bikes. Covertcat ( talk) 16:56, 7 January 2010 (UTC)
The article claims several advantages are offered ONLY by NuVinci CVTs (small size, in-line shafts, etc), despite there being other companies commercializing similar technologies. It looks like every single claim should be reviewed for veracity Au leon ( talk) 07:26, 30 June 2010 (UTC)
These have been around for years in industry. Two disks face each other, driving by friction through a ring of spherical balls. The balls are fixed on tilted axles. Changing the tilt axis of the balls changes the relative radius of their contact circle with the two disks, thus changing the overall gear ratio.
So what's NuVinci's innovation, in addition to this? Andy Dingley ( talk) 09:37, 30 June 2010 (UTC)
This material is interesting, but it needs a source:
Anyone? - AndrewDressel ( talk) 05:39, 26 July 2011 (UTC)
The article states, "However, unlike toroidal CVTs, it distributes the transmitted torque over several spheres, thus lowering total clamping force required." For any given gear ratio, the total clamping force required depends on the torque (that needs to be) transmitted and is actually independent of the number of spheres! This is because transmission is via traction (static friction), the maximum total amount of which across all balls will be proportional to the total clamping force. Increasing the number of spheres reduces the clamping force PER SPHERE, not the total clamping force.
My goodness, this whole article is riddled with faults and stuff that makes no sense. I might just have to create a Wikipedia account to do some more thorough (and more accountable) editing in order to counter this overly-optimistic, badly written sales pitch that currently stands... 109.145.82.160 ( talk) 02:37, 28 July 2011 (UTC)
This article is an advertisement and should be deleted. A short paragraph on the NuVinci wheel hub should be added to the history section in the NON-proprietary encyclopedic article titled CVT, just like all the other proprietary mentions. - Dirtclustit ( talk) 21:46, 18 January 2015 (UTC)
What are the model variations - and is the purpose each a variant of its own or are they all the same? [ Enviolo:history] names e.g. for 2017 the N380f and N380x. Enviolo names N170 for 2007 and N171 for 2008, the table here names N171 only, for 2007. The enviolo web pages is extremely unclear about model's names. Currently it does offer a city group with 310%, although there is no name for any N310 anywhere. N380 "Trekking" is up to 180 kg, 85 Nm, 250 W, 180 mm Disc. N380 "Sport" and "Cargo" are up to 200 kg, 100 Nm, 500 W, 203 mm Disc. "Commercial" is 310 %, 160 kg, 50 Nm, 250 W, 180 mm Disc, as is "City". No weights are given. -- Traut ( talk) 10:26, 17 June 2021 (UTC)
I just wanted to suggest that the article be updated to reflect that the product "survived" several bankruptcy restructurings. Flibbertigibbets ( talk) 20:32, 10 November 2022 (UTC)