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Hello all,

I am carrying out initial market research for my Final Year Project for my BEng Mechanical Engineering Degree at the University of Hull. I would be incredibly appreciative of any response and questions you may have. I am very new to the idea of FatBikes so please if I am stating incorrect information please correct me. My supervisor at the University of Hull has given me the following task:

A new generation of off-road bike, so called 'FatBikes' utilise large (100mm wide) tyres running at relatively low pressures (5-20psi) to handle soft terrain like snow, mud and sand. Conventional portable bicycle pumps are designed to deliver low volumes of air at high pressure (60-120psi). Fatbike tyres are relatively easy to puncture and cyclists are faced with an onerous task to repair and re-inflate them when 'on the trail' due to their relatively large volumes. Additionally cyclists like to 'tune' the running pressure to the terrain, and therefore some means of measuring the absolute pressure accurately is required. The scope of the project is to design and evaluate a low-weight, highly portable, manufacturable solution to this issue. There is no preferred conceptual solution, the project should include a widely ranging survey of air-pumping technologies.

Adding to this, im hoping to manufacture a prototype and then test it.

Firstly can anybody suggest any pumps on the current market and/or send me a link to the relevant websites?

Sounds obvious but do FatBike tyres have an inner tube and is the value on this inner tube the same as a conventional bike tyre?

Many, many Thanks

Finally can anyone suggest any good ideas going forward and what the general public (fat bike users) would like to see in this sort of design?

Dave
 

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I think the key factors here are low pressure and high volume. Both should change the optimal design of the pump substantially. Someone in another thread suggested a bag/foot pump system, and I think that’s a good idea to explore. 20 psi is not very high, especially if you can design a bit of a mechanical advantage into your pump.

Is your name a reference to Davey Boy Smith, btw?
 

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turtles make me hot
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I carry a Topeak Mountain Morph in my Camalbak. It pumps up my 29x2.3 tires very quickly and I'm sure it would do a fat tire in an acceptable amount of time. The same thing with a fatter chamber would do exactly what you're talking about.
 

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M8 M12 M15 deez nuts
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I run the super-heavy Pricepoint-branded 2.5-2.8" downhill (DH) innertubes, the Schrader variety. I pump roughly 4 ounces of Stan’s flat-suppressing gunk into each innertube. So far, I’ve only had one flat, due to a long, wide pointy piece of metal in the middle of the trail that oughtn’t have been there.
 

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Rednose/Greenback
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" Fatbike tyres are relatively easy to puncture and cyclists are faced with an onerous task to repair and re-inflate them when 'on the trail' due to their relatively large volumes. Additionally cyclists like to 'tune' the running pressure to the terrain, and therefore some means of measuring the absolute pressure accurately is required. The scope of the project is to design and evaluate a low-weight, highly portable, manufacturable solution to this issue. There is no preferred conceptual solution, the project should include a widely ranging survey of air-pumping technologies."

Here's one possibility.
Alpaca pack rafts have inflation bags that seem effective, at least on their tubes. Wind gusts (like milage) may vary, but inflation it is. And it's green tech. One of mikesee's AK videos (Yakutat to Glacier Bay) briefly shows the bags being used in windy conditions. It's on this forum but I'm not sure which thread. You can also see it on Vimeo . The wind inflation is around 3min into the clip, though you'd be crazy not to watch the whole thing.

I don't know if this method has been tried on fat tires yet, but it's possible. Design and fabricating an adapter to service presta and shrader type valves would be key. The bag should be easy.
 

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A pump that was driven by turning the cranks would be interesting...if you could design out the million or so shortfalls that immediately come to mind then that would be even better.

A rotary vane type pump rather than a piston type is good for high volume, low pressure...making it work sensibly is your challenge
 

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Premium Member
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Hello all,

I am carrying out initial market research for my Final Year Project for my BEng Mechanical Engineering Degree at the University of Hull. I would be incredibly appreciative of any response and questions you may have. I am very new to the idea of FatBikes so please if I am stating incorrect information please correct me. My supervisor at the University of Hull has given me the following task:

A new generation of off-road bike, so called 'FatBikes' utilise large (100mm wide) tyres running at relatively low pressures (5-20psi) to handle soft terrain like snow, mud and sand. Conventional portable bicycle pumps are designed to deliver low volumes of air at high pressure (60-120psi). Fatbike tyres are relatively easy to puncture and cyclists are faced with an onerous task to repair and re-inflate them when 'on the trail' due to their relatively large volumes. Additionally cyclists like to 'tune' the running pressure to the terrain, and therefore some means of measuring the absolute pressure accurately is required. The scope of the project is to design and evaluate a low-weight, highly portable, manufacturable solution to this issue. There is no preferred conceptual solution, the project should include a widely ranging survey of air-pumping technologies.

Adding to this, im hoping to manufacture a prototype and then test it.

Firstly can anybody suggest any pumps on the current market and/or send me a link to the relevant websites?

Sounds obvious but do FatBike tyres have an inner tube and is the value on this inner tube the same as a conventional bike tyre?

Many, many Thanks

Finally can anyone suggest any good ideas going forward and what the general public (fat bike users) would like to see in this sort of design?

Dave
I do not agree that fat tires are easier to puncture than "regular" mtb tires.

The pump needs to deliver high air volume, be easy to use, light weight, and compact.
No need for anything fancy about the design. Accuracy in the pump is not needed. Not really possible to get an good reading at low pressure with a portable pump. A separate digital gauge is better.

Topeak, SKS, Blackburn, Zephal are a few of the major pump companies.
 

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Velobike got me thinking about something in a previous post, but for a fat bike, something like an airbed pump.
Using a bellow or diapragm type design, from a lightweight material that has shape memory & a non return valve.
Roll up, pop up, high volume, low pressure pump with no moving parts.....it's the future ya know! ;) :D
 

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Rednose/Greenback
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I thought it was cool how they inflated the rafts in the AK video. But I am skeptical as to how practical this would be with tires. While it might prove viable as an accessory means of inflation (depending on environment) , I'd still bring a pump.

What I'm waiting for is the nano tech PSI sensor built into the tire sidewall that displays results near the valve stem.

I know, dream on...
 

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I wanna see a rechargeable HP cartridge system (regulated) that is attached to the bike that is hooked to a bar valve that lets me deflate & inflate on the move.
Fatbike version of what you see on logging trucks, the arrive on road at normal pressure, then drop it down to drive on the mud & pump them back up again when they leave.

Being a hydraulics engineer, I feel a project coming on lol:D
 

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Is it just me, or do others think the OP is picking our brain to hopefully cash in someday. Any old pump will pump tires. This isn't rocket science or marketing research. Maybe I'm too cynical, but truth be told I don't trust humans. Humans are users. Everyone has an angle for selfish reasons....except me...and maybe some of you :thumbsup:
 

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A Surly Maverick
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I wanna see a rechargeable HP cartridge system (regulated) that is attached to the bike that is hooked to a bar valve that lets me deflate & inflate on the move.
Fatbike version of what you see on logging trucks, the arrive on road at normal pressure, then drop it down to drive on the mud & pump them back up again when they leave.

Being a hydraulics engineer, I feel a project coming on lol:D
Do it! Do it! Do it ! :thumbsup:
 

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will rant for food
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Is it just me, or do others think the OP is picking our brain to hopefully cash in someday. Any old pump will pump tires. This isn't rocket science or marketing research. Maybe I'm too cynical, but truth be told I don't trust humans. Humans are users. Everyone has an angle for selfish reasons....except me...and maybe some of you :thumbsup:
It might be just you, but it also doesn't matter. Hear me out:

It's hard to get a good product off the ground. Did some patent work and product pitches (totally un bike related) a number of years ago for a "value added" product and it can be really hard convincing people to give you money for production versions. If he succeeds at making some cash while I inflate my tires more quickly, then, win-win.

Yes, any old pump will pump tires, eventually. I think many could appreciate a pump that would get rid of the "eventually" part. A high volume / low pressure / bidirectional pump would be awesome. A portable one, at that? Youch, sounds difficult.

As an aside, I too disagree that fat tires are inherently more easy to flat. I have to be pretty reckless. The only time I've pinch flatted was with minimal (flailing on the rim) pressure, and I meant to lift my rear wheel over a curb, and screwed up, smacking it into the curb with more force than I otherwise would have. Anyway, that's just an anecdote, I don't ride everywhere, it's not thorny where I live.
 
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