Biking into the dust. General Bike info for the Playa.

[Captain Goddammit]

Or do what I did, put cruiser bars and seat on a mountain bike (I went with the Mongoose Dolomite, 26"x4", oh yeah!) and get the upright position. How does it work? Hell I dunno I never actually ride it, but it looks like it probably rocks.

[Elliot]

All my bikes get a BMX handlebar. This bike started life as a ten speed "racer" with "upside-down" handlebar.

With a cruiser saddle, you have to sit a bit lower, because you cannot get full leg extension. The wide part of the saddle interferes with downward movement of the thighs. While leg extension is very important, I find that a compromise with a cruiser saddle is best for me.

With a single speed bike, you may want to change the drive ratio, by installing either a smaller front sprocket or a larger rear sprocket (or both). I have solved many bizarre complaints ("no traction", for one) by simply making the bike easier to propel. You will travel a tiny bit slower, but that's immaterial.

As for mountain bikes, I discard the front derailer and leave the chain on the middle sprocket. This eliminates 90% of gear troubles.

EDIT to add: The back-swept cruiser handlebar that people like so much for the cool look... is the pits to ride with, because your knees can hit the handlebar. I'm guessing that's why we see so many of these bars turned upward -- which leaves the grips at no angle possibly suitable for the human hand.

[Ann_Vader]

What they said! Widest tires that will fit in the fork and the rear stays, with something like 1/4" minimum clearance on each side. And fairly smooth "city" tread. 26 x 2.125 is a common size, but may be too wide. A smaller common size is 1.95.

And FIGJAM's point about inflation relates to the fact that if a tire is fully inflated at low elevation, it may detonate at high elevation where the atmospheric pressure is lower. (Calculations do not support this concept, but empirical evidence does. It has definitely happened to me.) Then use full pressure as marked on the tire while on Playa.

I highly recommend you install Thorn Resistant inner-tubes. The rubber is twice as thick as normal, which greatly reduces punctures from all sources. They also hold pressure longer. They cost around ten bucks, which is a bargain for what they do.
Some Thorn Resistant tubes come with liquid sealant inside. A common brand is Slime. This does no harm, and can help. Just be aware that the stuff makes an unholy mess when the day eventually comes that it escapes. Luckily, the stuff washes away with water.

A comment on terminology: You used "Ashtabula" and "saddle". You are one of us!

hahha! Elliot, I am one of us... Many years of bicycle shop and cycling industry employment. A little racing, road and ATB, now I just ride for fun and fitness.

I had an impressive collection of bicycles which I have been slowly parting with over the last couple of years. I'm now down to 4 from a high of 26.

I can definitely fit *some* 1.95" tires in the rear triangle without rubbing, I've had more lucks with a slick than something really knobby on this bike. Its got ancient and dry rotted Avocet cross tires on it at the moment (I just dated myself if you remember when Avocet made tires).

I'm not fond of slime at all, but will certainly set up the tires with thorn resistant tubes and include an extra thorn resistant in my repair kit.

Good point about inflation! I'm loading my bike in the DC container and we are pretty much sea level here, but my stuff will be going up higher on its way to the playa. Sounds like I need to leave just enough air to not pinch the tubes in transit. I can re-inflate on the playa, I'm sure.

[Captain Goddammit]

Since it's a scientific fact there's barely any measurable change in air pressure between seal level and the playa, I'm guessing the claimed cases of exploding tires are because of the tire heating up in the sun. I've had an old car tire sitting in direct sunlight on a very hot day explode.
Otherwise it's horse dukey, a psi or two isn't gonna do anything or we'd all have flat tires on all our bikes, cars, trailers, etc.

[Ratty]

Capt. Just because it hasn't happened to you doesn't mean it is horse dukey. You are coming from sea level? Might I suggest that you inflate your bike tires fully before you come? Put it to the test. Even potato chip bags pop coming over the hill.

So research online fully supports that pressure won't increase enough to explode. You are right.

To all the people that have had their tire explode in their car or trailer, protected from heat and cold, you are also right.

Win, win. Drinks for everybody.

[Elliot]

As I indicated earlier, calculations and field-experience are at odds here. Faced with an actual physical bicycle, I go with my experience. (Much the easier for me, since I flunked math in college. LOL ) Solar heat could very well be a factor.

AND... cheap tubes are almost certainly a factor. The tubes in $69.95 bicycles (such as the notorious Huffy Cranbrook) are of grotesquely poor quality.

Another factor in my experiences is that I carry so many bikes. So two or three explosions in transit is a modest percentage.

No need to deflate very much. If full pressure is 60, you will be plenty safe with 40 in transit. But do air it to 60 as soon as you arrive on Playa.
Our camp will have an air hose out by the street 24/7.

Since many Burners will read this between now and the Burn.... Under-inflation is by far the dominant reason for flats. And a cheapo bike, even brand new, can lose 20 PSI in a week!
That's the main problem with the Yellow Bikes. They are all Huffy Cranbrooks, with 4 cent inner-tubes. And they are always riding around on 10 or 20 PSI, and....

Oh... and... Ann_Vader, if you are ever bored in BRC between Noon and 6, we can always use an extra Technician. No dental plan or 401k , but all the wine you can guzzle.

Ooooo.... (late addition, thanks to Ratty) I used to work in trucking. We hauled truckloads of potato chips and the like for the biggest brand of such. One regular run was from Fresno, California, to Denver, Colorado. The shortest route is I-70, over an elevation of more that 11,000 feet. These trucks are banned from using that route, because the cargo explodes. Instead they use I-80, at only 7,000 feet, and the driver must document on arrival that he drove that route.

[Captain Goddammit]

I have brought bikes from sea level (Seattle) and I always have them inflated to the max for lower rolling resistance, before leaving home.
It's a fact, look it up wherever you trust, 4000 feet of elevation isn't enough to blow a tire. I'll bet you can add 3 psi, which is more than the differences that altitude makes, to any bike tire in all of brc and not one will explode because of it.

However, temperature also affects air pressure. Every 10 degrees causes around one psi increase. I put forth that a lot more pressure can be created by a black tire baking in the sun than the maybe ONE or TWO psi the elevation change causes.

Maybe you've seen bike tires blow up but claiming it happened because you gained TWO psi? Really? Bike tires are not so sensitive that one or two psi will explode them. I'll bet large sums of money this summer in person that you can't add two psi to any bike tire on the playa and blow it up. (Starting at the tires max rated pressure and a tire in reasonable condition)
I'll add further, if the pressure change due to altitude were so great it could blow out tires, YOU wouldn't survive the trip! Your own body is far more sensitive to pressure change than bike tires are.
Wives tales... sheesh.

[Elliot]

Your numbers are unquestionably correct, mon Capitan. And your premise of walking around with a pump and adding two psi to a bunch of tires, is also no doubt solid. Out of 140,000 tires, over eight days, it is highly unlikely that a single one would pop from a 3 PSI pressure increase alone.

But one factor alone is rarely what pops a tire (or the tube inside it), I would venture to say. It's a combination of factors added up. Age; exposure to sunlight over time (if parked outdoors year 'round); a grain of sand or other debris between the tube and the tire from the day it was assembled, slowly digging a weak spot in the tube; a sharp spot on a spoke-nipple just barely poking thru the rim-tape, digging another weak spot; and so on. I find many rim-tapes out of position, exposing a spoke-nipple, and similar flaws, slowly but surely eating away at a tiny spot on the tube. And one day... one of those weak spots gives out, for no one reason at all.

And I have seen -- and heard -- a number of them rupture with a bang while sitting parked in BRC. In fact, it has happened to a couple of our customers while they were waiting to get one flat fixed -- bang -- suddenly they needed two flats fixed. Increasing heat is likely the triggering factor in many of these cases -- as the Goddamn Captain also correctly points out.

So my thinking is to minimize the risk of this happening at any stage of the adventure, by eliminating the one factor that can so easily be eliminated. And this is to have the pressure a bit below max while traveling, and air it up to full pressure after arriving in BRC.

It's a philosophy, rather than science. And I remember both my grandmothers as pretty sage philosophers.

While I'm at it.... Beware of white sidewall tires. They crack and rupture far sooner than black ones.

Tires are black for a reason. Rubber is white, and 120 years ago all tires where white. And wore out very fast. The solution was to add "Carbon Black" to the rubber. Carbon Black is essentially coal dust. Mixed into rubber, it makes the rubber much stronger.

Car tires with white sidewalls are black tires with a thin layer of white rubber added. Not so with bicycle tires. On bicycles, white sidewalls are white rubber all the way thru.

Hopefully, Ranger Magnum will drop in and share his professional expertise on tires. (Unless we are bored silly with Carbon Black and such stuff by now.

(Boring anecdote: I once picked up a truckload of Carbon Black at a mine, high in the mountains of Colorado. The miners completely covered themselves in a white powder -- I'm guessing chalk -- before entering the mine. This kept the carbon black from getting into their pores and sticking there. The chalk powder washed off easier and took the black dust with it. Scary. )

In other news.... I found a vintage Schwinn cruiser, and also a vintage Schwinn "drag slik" tire, among bikes donated to the camp last year. Captain Goddammit will be turning this into some pretty goddamn cool custom bike (with or without the drag slik tire). NIfty Stuff coming up!

(Lord, sometimes I go on and on, don't I. )

[BeeWeeDee]

... air pressure between seal level and the playa, ...

I kind of like this image in regard to this thread.

[Captain Goddammit]

ducking auto-correct. I mean ducking. I mean fuckinh auto correct.

[cranberries]

There is no sand on the playa.

The surface is like concrete, covered in baby powder. In the deep playa it can be soft and rutted and crazy, but closer to "town" or Center Camp the surface is often smooth-ish, but deep ruts and dust-filled potholes can form, especially after rain like 2014.

A week on the playa isn't going to hurt a bike. If you ever spent time in a cold climate and ride through rain, now and salt, that is MUCH worse for a bike. That takes years of neglect to start to harm ferrous parts of a bike, so a week on the playa isn't a big deal.
...

Playa dust doesn't trash a bike. It doesn't ruin anything. The dust is about 3 microns and is electromagnetically conductive (it gets into everything) and finds itself in odd places, it's not going to be a problem for a properly maintained/built bike

As a geologist, I'm gonna challenge this conventional wisdom a bit... the loose sediments that make up the surface of the playa are *mostly* smaller than sand-size particles, but not completely. Sand-sized particles range in size from 1 mm to about 125 microns. (For reference, 0.25 mm/250 microns is about the smallest particle that a person can "feel" or sense as sandy grit). Given the nature of the sediment source for the playa (mountains) and the processes that transport and deposit the playa sediments (wind and water) it's geologically and physically impossible for only the smaller-than-sand-sized particles to end up there. The depositional environment is dominated by wind, but any deposit and transport done by water is going to include sand-sized stuff. It's how geology, which is essentially physics with a large timescale, actually works.

As it happens the first thing I did when I got to the playa last year was taste it (ask any geologist, most of us have or would do this). It tasted like approximately 30 percent sand. To confirm this, I had some friends in a lab do a hydrometer analysis and sieve test when I got home last year: 40 percent of particles were greater than 150 microns in size.

TL:DR - don't assume that the playa dust has no corrosive grit in, because it does. Is there enough in there to cause problems with a bike over the course of a week? Could be? Probably depends on what other steps you're already taking to clean, maintain, and protect your bike.

[FIGJAM]

I won't argue with the Capts, science, but in 2013 I bought 2 new tires and tubes for the back of my trike.

Aired them to max and loaded the trike in the ENCLOSED playapod.

It doesn't get that hot in there, but when I reached camp and unloaded the trike, one tire and tube had blown out to unrepairable, and the other tube had blown out but just blew the tire off the bead.

I was lucky that Elliot could even find 24" tubes in his stash, and one 24" tire.

I haven't traveled with them fully inflated since.

[Elliot]

Cranberries, this is good information about the particle sizes. What is the smallest particle size?

[Canoe]

I have brought bikes from sea level (Seattle) and I always have them inflated to the max for lower rolling resistance, before leaving home. It's a fact, look it up wherever you trust, 4000 feet of elevation isn't enough to blow a tire. ...

Except, not everyone is taking the same route you are. 4,000 is a descent from the peak of any of my routes. You don't know their starting elevation and temperature, nor the condition of their tubes. Some travel up over 10,000, then combine that with temperature increases from where it was originally inflated. Easy insurance to avoid such issues is to reduce tire inflation.

Particle size?
There was this:

Typical particle size distribution of BRP soils.
Particle Size Weight Percent
Sand (>62.5um) 3.1%
Silt (15 - 62.5um) 10.4%
Silt (3 - 15um) 21.2%
Clay (<3um) 65.3%

Black Rock Playa particles:
Desert Research Institute, Black Rock Playa, Northwestern Nevada: Physical Processes and Aquatic LIfe, Kenneth D. Adams and Donald W. Sada, May 24, 1010, Page 4.

[Elliot]

...Where um = Micrometer = o.oo1 Millimeter = commonly called Micron. Now I just have to remember which is which of > and <.

Thanks, Canoe!

[cranberries]

Particle size?
There was this:

Typical particle size distribution of BRP soils.
Particle Size Weight Percent
Sand (>62.5um) 3.1%
Silt (15 - 62.5um) 10.4%
Silt (3 - 15um) 21.2%
Clay (<3um) 65.3%

Black Rock Playa particles:
Desert Research Institute, Black Rock Playa, Northwestern Nevada: Physical Processes and Aquatic LIfe, Kenneth D. Adams and Donald W. Sada, May 24, 1010, Page 4.

Good to know! Perhaps my sample was sandier than average.

[Canoe]

Good to know! Perhaps my sample was sandier than average.

There's the crust, variable each year depending on that year's precipitation, and the underlying 'soil'. I expect their samples weren't taken during a burn after getting broken, crushed, churned up and redistributed/shifted/arranged by the wind, feet and 'vehicles'. And it varies across the playa. BRC is placed in the least bio-significant part of the playa (I'm thinking that's not by co-incidence). Other locations on the playa are much more biologically active with the micro-fauna and the migratory birds. Which leads me to, what makes up those particles is also interesting: fine clay or other soil components (SiO2, Al2O3, quartz, micas, calcite, feldspar, vermiculite, illite, and kaolinite), aquatic micro-fauna eggs or dead body parts, bacteria normally on the playa, bacteria deposited by migratory birds, bacteria blown in off of surrounding land or the bacteria in the water that the water trucks spray on the dusty BRC roads, plus that tracked out of the porta-potties.

[cranberries]

Good to know! Perhaps my sample was sandier than average.

There's the crust, variable each year depending on that year's precipitation, and the underlying 'soil'. I expect their samples weren't taken during a burn after getting broken, crushed, churned up and redistributed/shifted/arranged by the wind, feet and 'vehicles'. And it varies across the playa. BRC is placed in the least bio-significant part of the playa (I'm thinking that's not by co-incidence). Other locations on the playa are much more biologically active with the micro-fauna and the migratory birds. Which leads me to, what makes up those particles is also interesting: fine clay or other soil components (SiO2, Al2O3, quartz, micas, calcite, feldspar, vermiculite, illite, and kaolinite), aquatic micro-fauna eggs or dead body parts, bacteria normally on the playa, bacteria deposited by migratory birds, bacteria blown in off of surrounding land or the bacteria in the water that the water trucks spray on the dusty BRC roads, plus that tracked out of the porta-potties.

Yep, 100 percent agree. The playa where we have the Burn also accumulates sediments/material brought in by all of the tens of thousands of vehicles, and dirt from shipping containers, and all of the other sand-sized pieces of stuff that are non-native but don't necessarily count as MOOP. Thanks for helping me derail a perfectly good thread with geology! nicely done .

[DerbyDave 18]

Got a question. I know next to nothing about bikes. This will be my third burn this year. My first year I had a generic bicycle and it was fine for the most part. My second year I was told to get a cruiser with the wider tires and no gears. I had a really hard time riding that thing for some reason. I have been given a racing bike and I'm wondering if I change the narrow seat for a wide one and change the handlebars so they're regular ones and not the ones that curl down would that possibly be a good bike to use or should I try another one with the fatter tire again? Maybe the one I got just wasn't a good model. I actually missed a good amount of art because I couldn't bike that far out without dropping over from exhaustion because it was such a strain.

[BBadger]

My bikes were okay the first few burns, but this past burn I wanted a much nicer ride after loaning someone's cruiser for the burn. I had no experience modifying bikes, but after reading some advice on the board, reading online, and asking some advice from Elliot, I did the following, which made for a nice ride last year:

1) Bought a regular ol' Huffy Cranbrook for $80 at Walmart. I had usually used old mountain bikes, but I wanted a simple cruiser. The tires are not fat, but I didn't find it mattered much; the gear ratio is what mattered to me.

2) Swapped out the gears for a much lower gear ratio. I got a cheapo 36T chainring and a 20T sprocket, though only used the chainring; I'll use the sprocket this year though. The default gear ratio is too hard to pedal, and this is what scared me away from cruisers until I tried a nice down-geared version in 2015.

3) Swap out the handlebars for some ape hangers. The handlebars on the cruiser weren't horrible, but I wanted to be able to sit straight up and steer instead of face forward. Note that you may need to adjust your brake cable to do this.

4) Got a layback seat extension such as this (I got some other one, but it looks like that) for my seat. I'm relatively tall, so this allowed me to set my seat back quite a bit further so that my legs were in a more comfortable position.

5) Got a rack for above the rear tire, and fixed a basket to it. This allowed me to put bags of ice on the back so I could ride it back home instead of packing them on my lap or handlebars and tipping over all the time.

6) One advice of this board, put an assload of marine grease on the bearings.

7) Bought some metal pedals for the bike. I didn't want the plastic ones that came with the huffy to break.

8) I already had a nice cruiser seat so I used that, but the Cranbrook comes with a decent seat as well, so you may not need one.

All this took a week or two of intermittent work to fix and get ready. I learned how to fix up the bike, grease it up, make it work nicely, and how to pack it up for transportation. Good learning experience and the bike worked nicely.

[maladroit]

Same process here. While I'm starting with a Beast fat bike rather than a Cranbrook, I also swapped a gear for easier pedaling last year and added a rear rack for hauling ice. The high handlebars were added a couple years ago as well as the wide comfy seat.

A cruiser with 2"+ wide tires will do fine, but I will never stop recommending the 4" wide tires on the playa. They're just perfect.

[Ratty]

Derby Dave a racing bike is a very bad idea. You won't get around at all with those skinny tires. Sometimes the open playa is just to full of loose drifts to peddle through. One important thing is that the bike fits you. Seat to pedal length and shoulder to handle bars. A basket on the front with weight in it will make it harder to maneuver. There is also a big difference in the way a cheap bike rides compared to an expensive one. You can improve the cheap ones with proper assembly and a few accessories. If your seat is uncomfortable add foam and a cover. Simple but magical.