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General Category >> Technical >> Internally Geared Hubs
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Message started by UofHLesley on Jun 12^th, 2009, 3:06pm

Title: Internally Geared Hubs
Post by UofHLesley on Jun 12^th, 2009, 3:06pm

Hello all,

My senior design team has thrown around the idea of using an internally geared hub, and it has been suggested by many people for use with a city utility vehicle. One brand that was seen at the competition this year was a NuVinci hub. I have read a review that it is bad for heavy vehicles and climbing with recumbent bikes/trikes. Does anyone have experience with that on in particular or others to share?

Also, internally geared hubs substantially increase the cost of a trike, so how much are they really worth it? What would be the cheapest ones you have heard about or used that still are of good quality where they would be dependable (7 or 8 speed)?

We are going to try to get one donated, so I need to know where to look. I have the information for a NuVinci contact person, but I wouldn't want to ask for such a valuable donation if it were not practical for a relatively heavy recumbent trike.

Thank you!

Lesley

Title: Re: Internally Geared Hubs
Post by FlyingLaZBoy on Jun 12^th, 2009, 3:18pm

It's not an answer to your Hub question, but has your team attempted to contact Cycle Genius, down in your area?

Title: Re: Internally Geared Hubs
Post by irodguy on Jun 12^th, 2009, 3:22pm

Again probably over all a better question posed on Atomic Zombie since all those guys are home builders. I can tell you that most trikes are not internally geared. I think the suggestion to contact Cycle Genius is a good one.

Title: Re: Internally Geared Hubs
Post by UofHLesley on Jun 12^th, 2009, 3:31pm

We have visited Planetary Cycles multiple times now and everyone has been very nice and helpful. That's where 3 out of 4 of our members got to ride our first recumbent ;D Also, we are trying to get a hold of Danny from Cycle Genius because we know he would be of great help to us. So far we have not had luck through email and leaving literature. I am going to try to hunt him down next week. Wish me luck! ;)

And irodguy, I haven't gotten to look at atomic zombies site yet, but I will. That would be a very fitting place for most of our questions!

Thank you!

Lesley

Title: Re: Internally Geared Hubs
Post by goatstick on Jun 13^th, 2009, 11:19pm

UofHLesley wrote:

I've blown up two SRAM 3-sp hubs (the fairly recent 9-sp ones) on my trike. Both times I was accellerating hard from a stop. SRAM warrantied the first hub but said they weren't intended for trikes. no luck on the 2nd. I crank a trike pretty hard though, and often hit 150 rpm getting up to around 20mph on the first accelleration stage. I finally bought a 40 spoke 4x tandem wheel which fixed those problems plus the wheel doesn't flex much in the corners, even at 40mph.

Title: Re: Internally Geared Hubs
Post by FlyingLaZBoy on Jun 15^th, 2009, 2:03pm

Internally geared hubs are out there, but I've heard they're expensive. From what I understand as well, they don't give you as close of a "step-up"/"step-down" range as a typical cassette, but if "external" simplicity is a priority, it could allow you to eliminate the triple chainring / rear derailleur mechanics.

By the way, what's the overall rough BUDGET for this vehicle of yours?

Title: Re: Internally Geared Hubs
Post by UofHLesley on Jun 15^th, 2009, 2:30pm

FlyingLaZBoy wrote:

Our overall rough budget is about $7,000, but $4,000 of that is travel expenses to go to the competition and haul the vehicle (budgeted for the farthest location of this year's US competitions). The construction amount is so high because we still are in the process of detailing our design and figuring out which parts we are going to use. Also, we might have to get outside help with processes we do not have the capabilities of carrying out at school and order custom parts. As we make more decisions the budget amount will hopefully be decreasing. Realistically, we probably will not be employing an internally geared hub due to the cost and limitations they impose. We still have to decide this as a group though. Many people have recommended we use one, so that is why we have been looking into it and getting opinions from those more experienced with the subject on here.

There are further explanations of the budget on our website www.teamrecumbent.com/budget.

Lesley