Single Chain Ring Considerations

A Canadian Peugeot with single chain ring and spider mounted chain guard.

Most of my bikes have multiple chainrings – double or triple.  I’ve gotten so used to the shifting patterns on my bikes, that I don’t think much about the double rear shifts that might be required to maintain cadence when shifting the front ring, nor do I worry that I might have to trim out the front derailleur from time to time (I use friction shifting for the most part).  But, that is not normal.  I am a geek, and the vast majority of cyclists are not (no offense to the wonderfully geeky readers of this blog).  Non-geeky cyclists are probably drawn to the seeming simplicity of a single chain ring up front.  Less shifting equals better riding, right?

The only bike in my constellation of daily riders with a single chain ring up front is my 1987 Panasonic MC 7500 – a bike I acquired as a frame and fork and then built into a city commuter.  Even though it’s the heaviest bike I ride, it’s the one that gets the most daily use.  One of the reasons for its appeal as a commuter bike is the simplicity of its equipment.  It has a rear freewheel with 6 speeds and plenty of range, plus a single chainring up front.  I installed a $7 ratcheting no name friction shifter on the handlebar to move the rear derailleur, and the shifter works intuitively with the lower end but perfectly decent Shimano Acera long cage rear derailleur.  At first, I didn’t use a chainkeeper, but experienced the chain jumping off on a few occasions, so decided to install Paul’s chainkeeper.  Chainkeepers are designed to keep the chain from falling off either side of the front ring of a single chainring bicycle when shifting vigorously or oddly, as can happen when unexpected events occur while cycling, and especially while commuting.

After a few mishaps with Paul’s chainkeeper, the most recent of which caused me to re-locate this device, as shown above (it is now a “fender keeper”), I have been thinking about the way returning cyclists, as well as those not mechanically inclined might have dealt with my recent near disaster.

I was cycling home after a day at work, heading downhill when suddenly my cranks would not turn.  Since I was still freewheeling I knew that the problem was at the front of the drive train and I immediately suspected that the chainkeeper had become dislodged and contacted the chain.  I pulled over immediately, and after confirming this was true, disengaged the chainkeeper, as shown above.  I rode home with no further issues, but shifted very gently, hoping my chain would not jump off the front ring, and all went well.  It is unlikely that the average cyclist would have been able to diagnose this problem, much less solve it.  Nor should they really need to.  Instead, the marketplace needs some much better solutions to the single chain ring challenge.

1947 Camille Daudon with single chainring

Vintage bicycles with single chain rings don’t need chain keepers.  Why?  The rear freewheel will have only 3 to 5 speeds for the chain to navigate, causing the chain movement to be very manageable as compared to modern drive trains with 8 – 11 speeds at the rear.  For commuters, it’s not necessary to have tons of gears, but instead to have enough gear range to accommodate the hills you encounter on your commute.  So, 3 to 5 speeds might be all you need, if the gear range is appropriate.

Paul’s Chain Keeper

The problem with many chainkeepers, such as Paul’s, is that they work TOO well. Since they are designed to prevent chain movement, there isn’t enough clearance to provide for even the slightest change in chain angle, and they require extremely precise adjustment that can go out of whack with even a small mishap.

One solution is to put a spider mounted chain guard on the crank, and then use a seat tube mounted chain watcher on the other side.  Or, you can put two spider mounted chain guards on the crank – on either side of the chain ring.  Sheldon Brown published an article for Adventure Touring Magazine in 1999 which deals with chainring issues for touring bicycles, but he also includes some good advice on anti-derailment devices that can help prevent the chain from dropping off a single chain ring.

If you are going to convert your bike to a single ring up front, here are some points to consider:

Shorten the Chain – you will want to remove links from your chain in order to accommodate the switch to a single ring up front.  This will help to prevent chain slap and chain jump.

Decide about a chainkeeper vs. chainwatcher vs. chainguard(s):  Depending on the width of your rear cassette or freewheel, you’ll need to think about the demands you are placing on the front ring.  If you are trying to go with an 11 or 10 speed system at the rear, then you’ll need something to help deal with the extreme angles that the chain will experience at the front ring.

Make sure the rear derailleur can handle the range: when switching to a single ring up front, you often need to increase the range of your rear cassette or freewheel.  If you do so, make sure that your rear derailleur can handle the the bigger cogs.  You may need to adjust your b-screw, or invert it (a la Sheldon Brown) to get the clearance you’ll need for the larger cogs.

Or – shift carefully and don’t worry about any of this.  Occasionally your chain may fall off, and then, you’ll put it back on again.

Tires I have loved, and a few I have hated.

Cypres 650b

The amazing array of wheel diameters, tire widths, tread patterns, sidewall construction, and the debate over fat vs. skinny widths, and high vs. low tire pressure inspired me to share my own experience with bicycle tires.

I am also a motorcyclist, so my knowledge of tire performance and traction is informed by my understanding of how tires function on motorcycles. A lot of the same science carries over to bicycles.

In my own personal collection of bikes I can count 9 different rim diameters:  700B, 27″, 700c, 650c, 650b, 26″ metric, 26″ English, 26″ MTB, and 24″.  From there, rim widths vary, spoke counts and lacing vary, and tire widths vary.  Wheel construction also has a very important impact on ride quality. In my opinion, more spokes on the rim are better than fewer, and wider rims are better than narrower ones, at least for all non-racing applications (that is to say, most of the entire cycling population).

The research on tire width and construction relative to speed and comfort is very limited.  So I give kudos to Jan Heine and his team for sounding the alarm about narrow high pressure tires and their negative effect on performance.  Not to mention their negative effect on comfort, and the limiting effect they have on a cyclist’s ability to safely explore her or his surroundings.  Since most cyclists don’t have hundreds to spend on tires, not to mention thousands to spend on custom built bicycles, it is important to consider real world, long-lived, and reasonably priced tire and rim options.  Cyclists who use their bikes regularly for transportation figured this out long ago.

For anyone struggling to understand the bizarre nomenclature surrounding tire sizing:  you are not alone.  There is no consistency in size labeling (although that is improving), and even among tires that are purportedly the same size, there can be perplexing variation which can make it hard to mount the right sized tire to your rim.  Sheldon Brown’s site has a sizing chart and discussion which help to explain the strangeness surrounding tire sizing nomenclature.  If you are confused, join the crowds!  When in doubt, always measure your effective rim diameter in order to determine the correct tire size for your bike.  If you are removing a tire, it’s quite easy just to look at the size indicated on the sidewall to make sure you replace the old tire with the correctly sized new tire.  If your rim doesn’t have a tire, it probably has a rim diameter stated somewhere on it, if it is a newer rim.  Many vintage rims have no diameter indicated.

700A tires from the Land of Oz

Original 1929 Dunlop Le Pneu tires

700B tires

When I was restoring a 1929 Griffon, I needed to replace the corroded Dunlop Le Pneu tires.  No diameter was indicated on the old tires, so I measured the rim diameter and ordered 700A (642 mm) tires, which had to be shipped from Australia, as they were not available anywhere else in the world that I could determine.  When they arrived and I tried mounting them, I realized that I should have ordered 700B (635 mm) tires.  I incorrectly measured the ERD on the 1929 Westwood rims.  In retrospect, since I had the original tires, I should have measured their diameter instead.  700A and 700B sizes are not listed on Sheldon Brown’s chart because they are considered obsolete.  However, I found the 700B tires on Amazon, but you may be able to find these sizes in Canada and France, in addition to Australia.

So, what are my favorite tires?  And what tires will I never willingly ride again?  Here is my list:

My top three preferred tires for comfort, speed, and reliability are:

Compass Loup Loup Pass 650b tires

Panasonic Compass Loup Loup Pass 650b 38 mm – I use these on my 1980 Meral.  They are comfortable, oh so comfortable. I haven’t had a flat yet after a few thousand miles of mostly urban riding.  I keep the pressures low at 46 psi rear and 42 psi front, which seems to provide the optimal compromise between comfort and handling.

Panaracer Pasela Tourguard – 559mm/ 32 mm

Panasonic Panaracer Pasela – in all its models and sizes – used on my Terry and on many other bikes I have ridden.  I have found these tires to be very long lasting, although I have gotten a few flats on the folding version I use with my Terry.  Whether or not they are easy to mount really depends on your rim and whether you are using the folding vs. clincher model.  I prefer the folders because they are easy to carry with me when I am touring. The 27 inch size has a different tread pattern.  These tires are affordable, reasonably comfortable, and fast enough.  They are a good choice for all-round riding which is why I generally use them for my restoration projects.

2016-12-21-005

Compass McLure Pass 26″ tires – used on my Panasonic MC 7500 errand bike.  These tires replaced the frighteningly compromised Nimbus Armadillo 26 X 1.5 tires I had been riding.  The Armadillos, while never having a flat in over 6 years of use, were heavy and not very comfortable, not to mention the fact that they were splitting apart at the seams.  The McLure Pass tires have made the MC7500 faster, and much more comfortable to ride.  Tires really do make a difference!

My three second tier tires – good value and a decent ride:

Continental 700c Gatorskins

Kenda Raleigh 26″ tires

Panasonic Col de la Vie 650b tires

While I could mention many, many tires in this category, my top three mid-range choices reflect my own interests as well as the particular bikes I ride.  So, don’t take them to heart, too much.  The Continental Gatorskins are great tires for 700c road bikes.  I rode Gatorskins over many, many miles on my 1986 Centurion Ironman Expert.  They were comfortable for a narrow 700c tire, and I never had a flat in all those years.  The low-end Kenda tires on my 1950 Raleigh Sports Tourist were a surprise.  I had expected these tires to be really horrible, and had purchased them as a placeholder until I could find “better” tires for this vintage Raleigh.  In fact, the Kenda’s proved comfortable as well as bullet proof.  I’ve had no flats in the eight years I have been using these tires, which show no signs of wear, and no sidewall cracks.  I have mixed feelings about the Panasonic Col de la Vie tires pictured above.  I tried these tires out on my 1980 Meral, and they were quite noisy, slow and ponderous.  However, these tires have worked well on the older 650b bicycles I have restored, so I list them here as a decent option for a 650b rim.  In this category I should mention a few other tires I have ridden:  Ritchey Tom Slick 26″ tires, Panaracer Ribmo, and Vee Rubber Micro knobbies.  All equally reliable and of good quality relative to price.

Tires I Won’t Buy Again:

In this category I include the Specialized Armadillo tires, noted above, which literally split apart at the seams.  I also include WTB tires – namely any of their 700c touring tires, which are noisy, heavy and very uncomfortable. I also will not ride any Continental Touring tires.  Continental’s offering is not really a touring tire, but instead a heavy and inflexible tire which is not even okay as a commuter tire, as there are many other nicer options out there (see Panaracer, above).  However, Continental does offer other tires which I do like.  I won’t buy any Schwalbe tires, no matter what the model, as I have found them to be unbelievably uncomfortable and heavy.

I do like micro knobbies as an interesting option for multi-modal cycling.  I used these Thailand manufactured Vee Rubber tires on my ALAN with very positive results – they were fast on the road as well as sure-footed on gravel.  While tire choice is not only highly personal, it should also be based on the type of riding you do, as well as the type of bike you are riding. If you are not happy with your current tires, it doesn’t hurt to think about other options.  I have found that ride quality is significantly affected by tire choice.

Portland BikeShare: 2nd Thoughts

Image result for portland oregon 2017 traffic slow down downtown

With the bizarre traffic maelstrom in Portland, Oregon this spring of 2017, anyone trying to get downtown via car, bus, or MAX Train will be in need of some calming medications to manage their enormous frustration.  Meanwhile, bike riders are the sole bearer of efficient transportation via Portland’s streets which are clogged with construction, lane closures, light rail track repairs, bridge anomalies, and highway shutdowns.

Nike “swoosh” on Portland’s Bikeshare logo

You would think this would mean that enterprising commuters would seek out alternative methods of arriving at their respective destinations, and that they might consider using Portland’s Nike funded “BIKETOWN” bikesharing program.  Think again.

Never have more clunky bikes been pawned off on the public.  These machines feature massive wheel flop (disastrous for bikes designed for a front end load), a 45 lb weight, and, worst of all, a sit up and beg riding position that makes only very tall riders able to master these bikes with relative safety.  I have ridden these bikes exactly 3 times, and hope to never ride one again.  And, that’s me – I love to cycle!  What is wrong with these bikes?  Just about everything.

In fact, my Dad’s 1965 2 speed Schwinn American would be a far more comfortable and efficient choice for anyone seeking passage through Portland’s beleaguered streets.  The riding position on this bike is adaptable to many cyclist’s sizes, and its geometry and excellent bullet proof steel construction means that it has lasted through decades of abuse and neglect.  The handling on this Schwinn is intuitive.  You just get on and ride.

Not true with these BikeTown bikes which were built by SoBi.  One commentator has this to say about these bikes:  “These clunky SoBi Social Bicycles look like they weigh a ton, and have the maneuverability of a circus elephant. With the ongoing costs, invasion of privacy and potential liability on the user’s end – you might want to consider alternatives.” – Hobeken 411.

Indeed, one thing that Portlanders noted right away was SoBi’s demand that users of its system waive their legal rights.   This is yet another reason to re-think whether or not you want to attempt to ride one of these machines.

Image result for brompton bicycle

Brompton Folding Bike

I am a strong supporter of public transportation as a “public good”, and I also support bike share programs as part of the solution to many of the challenges facing urban environments.  I served on TriMet’s budget advisory committee for years, and count public transportation advocates as friends and colleagues.  In short, I am the last person you would expect to criticize Portland’s Bikeshare program.  The problem with the program lies not in its conception, but in its execution.  I would love to see a bike share program designed around user friendly bikes, such as this Brompton folder, pictured above.  Interestingly, Portland’s Brompton retailer – Clever Cycles – offers Brompton rentals. I might try this out!

Obviously, any bikes which are to be used for bikeshare need extra technology and engineering, but there is no reason that should come as a sacrifice to ride-ability.  Having observed numerous riders attempting to master BikeTown SoBi bikes, and seeing their consternation I think its time for Portland to throw in the towel on SoBi, and re-think the Bikeshare program.  We need to offer bikes to all kinds of riders, not just to tall and fit riders who can physically overcome the poorly designed weaknesses of SoBi’s offering.