Moulton TSR-30 Update

I’ve been back on the bike again now for almost a month, following a couple week medical ‘leave of absence’ of sorts, and have been riding the Moulton almost exclusively.  New toys always seem to get all the love.

Any minor teething issues that one inevitably has with a new machine  have been worked out, and that has allowed me to just focus on how it rides / performs, so at this point, I now feel like I have a more balanced / nuanced opinion to share.  And I’ll take the opportunity to point out a few mods and accessories I’ve added, too.

I have to eliminate one thought from your mind, just in case it’s there, before you read onward.  A Moulton is NOT a folding bike.  Not so much because it simply doesn’t fold, but because it doesn’t have even remotely the same design goals as a folder, and doesn’t really meet the same needs as a folder, either.  This is a real bike, for real rides, and seeks to be an ideal machine for the task of riding as much as possible.  It may happen to have small wheels, but that’s not so it will pack up small and be as transportable as possible.  The small wheels of the Moulton do offer some of the same benefits as they do on true folding bikes, but I think of that as mostly coincidental, if you will.  None of this is to say that folding bikes aren’t ‘real’ and that you can’t do significant rides with them, it’s just that they present some compromises in that field which are acceptable because you subsequently need to pack one away into a duffel bag or hallway closet in about 20 seconds.

Ok…..with that said, let’s interrupt the flow of the text even more, and skip to the last chapter (….then I’ll elaborate a bit on some of these points further……).

Highs:

• Lively ride and acceleration
• Superb handling at all speeds
• Quality construction and finish
• Effective suspension on medium and large road imperfections
• Quite versatile
• No discernible BB flex under hard pedaling
• Easy to separate, store, and transport (certainly not like having a folder; but still better than a conventional bike)
• Small wheels allow for slightly closer drafting and following

Lows:

• A few odd parts specs (1″ fork steerer, 31.8 mm seatpost, minimum BCD of 110mm, and proprietary BB+crank system that apparently nobody imports into the USA)
• Highest gear is too low
• Hard to fit water bottle cages
• Suspenson has no adjustability in the rear and is only minimally effective on chipseal
• Kinda heavy-ish (26lbs stock and unadorned, but with A-520 pedals)
• Kinda expensive (about $3,200 USD)
• Gateway Moulton drugs such as the TSR series only lead to the harder stuff later on, like the roughly £16,250.00 or $25,000 USD it costs for the for the top of the line stainless steel Double Pylon New Series model

Notable Neutrals:

• AFAICT, not significantly faster (or slower, for that matter) than a conventional 700c road bike.  But I need to do some more back to back rides with the Moulton and the  Spectrum, as well as do some CdA and Crr testing, before we have a true verdict.  I should note that my position on each bike is very very close (within 5mm on all fit dimenions except bar width).
• Quirky, attention-grabbing aesthetics
• High bottom bracket (about 11.25″) for no apparent reason
• Built by Pashley (for Moulton) in Stratford Upon Avon

Ride Quality , Handling, and Suspension:  Okay, this is it.  This is the main reason to buy a Moulton, at least in my mind.  There is a lot going on here, and there are some interesting synergies at work.  I’ll do my best to explain….

The Moulton TSR combines several unique elements – small wheels, suspension, and space frame construction (along with smart steering geometry) – that each add their own part to the overall ride experience, but a few of them work in combination to deliver a unique riding experience.

Firstly, the rims are ISO 406 (not your typical road bike 622).  So, depending on the exact tire chosen, the wheel diameter is somewhere between 18.25 and 18.75 inches.  These small wheels improve acceleration and decrease gyroscopic forces making the bike very easy to steer and lay it over for fast corners.  In addition, the typical Moulton experience ‘recipe’ calls for pumping up those tires pretty damn hard.  All of this makes for a very light and lively ride, and one that is never ponderous, heavy, or sloppy feeling.

However, those small wheels are going to dive further into potholes and manhole lids and have a harder time ‘climbing’ up pavement seams and patches, and the ride will be even worse if you are running narrow-ish, high pressure tires.  So the logical response was to  add in some suspension.

The suspension system on the Moulton TSR is not very complicated.  (The suspensions are a little more involved on some of more expensive models, but that’s another review.)  Actually, in certain respects, its primitive.  For instance, the rear suspension is completely non-adjustable and consists of a single pivot swing arm.  Modern mountain bikes, by comparison have hydraulic damped shocks and complicated geometries, and all sorts of other things I don’t know much about.  But, I do know enough to point out that mountain bikes have very different design goals than a Moulton.  The latter were designed as road going machines and their suspensions are geared around those short-travel requirements, while keeping weight, maintenance requirements, and general kludgery / ugliness to a modest level.  And with that in mind, the suspension design doesn’t seem so much ‘primitive’ as it does ‘appropriate’.

So, how did Dr. Alex Moulton do?  How’s the ride quality?  Excellent, actually.  I’d say that the front suspension makes up for the small wheel size in spades when it comes to bumps.  Comfort up front is actually a lot better than it would be with a large wheel and the same tire width and inflation pressure.  (Keep in mind that my main point of comparison is my Spectrum, with lightweight skinny steel tubes and shod with 28mm tires – equal width as on the Moulton.)  At the rear of the bike, the suspension makes up for the small wheel size there too, but with only a modest amount of extra softness to spare.  There is no doubt that the rear suspension is firmer than the front can be.  Can be?  I say that because you can adjust the pre-load of the front suspension, making it feel firmer or softer, and the damping is also adjustable, as your weight, road conditions, and preferences will dictate.  If the pre-load adjustment isn’t sufficient there is both a softer and firmer (aka ‘race’) spring available.  By contrast, the rear suspension lacks any adjustment whatsoever, and the Moulton literature says it’s “correct for all riders”.  (Huh.  Why did they do that / say that?  I have a half-baked theory that I will get to in a moment…..)

Critics of bike suspensions often like to point out that they are generally only effective on large imperfections,  and things like cracked pavement and chipseal get through.  Yes, to be sure, the suspension does not shine on those things, but it does seem to dampen it a bit.  It’s notable that the small wheel diameter is not really a liability in this case, but high pressure tires sure are.  While Moultoneers typically have used very high pressure tires, the TSR does have clearance for 33 mm tires without fenders (and V-brake models like the TSR-27 have room for even bigger, approaching 40mm I beleive), and that is wide enough to allow the use of an air pressure that helps soak up chipseal and the like.  You really can have your Perpetuem and slurp it too – suspension for larger bumps, and fatter tires / moderate air pressure for the small stuff.

Is life really that perfect?  No.  In case you were wondering, there are some down sides to the suspension, and that bad action is all up front.   The front suspension doesn’t only move in response to bumps, but to any forward weight shift.   Bobbing and brake dive are the often mentioned ones.  Brake dive happens, but I can honestly say that I have not found it problematic.  I haven’t done any true panic stops yet, so perhaps my opinion will change at some point, but in an effort to brake as hard as I dared in a controlled situation (the road in front of my house), I barely noticed the diving.  So far, I’d say it’s a non-issue.  Bobbing is a little different.  It’s not so great.  As I mentioned before in another post, you can minimize it through a combination of suspension tuning and technique, and you also simply get used to it.  But I won’t lie, I wish it didn’t do it.  I would welcome some sort of simple way to lock out the suspension from the saddle, and would happily engage it on long or very steep hills.  I should note that the bobbing is only a problem out of the saddle.  It is possible to illicit a small amount whilst seated, but only when using very hard and choppy pedaling efforts.  Furthermore, in this particular context, it’s not even that annoying like it is when standing.

So, does the front suspension bob actually slow you down?  Maybe a tiny bit.  I am not sure, but my hunch is yes.  Mostly, I think it does this by messing with the rider’s rhythm.  If you are one who rides out of the saddle a whole lot, then perhaps a Moulton is not the bike for you.

How about the rear?  Does it soak up any energy?  No.  Amazingly, it doesn’t seem to do that all, no matter how hard you mash the pedals.  The secret is in the fact that the entire rear triangle of the bike, including the bottom bracket, is a single, rigid piece, and there is actually no way for chain tension to actuate the suspension, short of the chainstays or seat stay flexing (which they don’t appreciably do).  Under hard pedaling, the bike feels like a panel.  Very solid.  This unified rear triangle is connected to the main frame at a pivot at the bottom of the seat tube.

Ok, but does it move in response to anything else (other than bumps)?  Well, yes, it moves in response to acceleration of the rider’s center of gravity produced by the rider’s legs going up and down as the pedals turn during seated riding.  Riding along, if I contort myself a bit to take a look at the rubber cone, you can see a rhythmic flexing of the suspension.  But unlike the front, this is not bothersome, and strangely enough, actually seems to impart a lively, energetic feel to the bike.   The sensation is what I imagine the mythical ‘planing’ effect to be like.  (For more on planing, read some of the links at the bottom of this post.)

I have noticed this effect comes and goes, and sorted out that it is highly cadence dependent.  Too fast or too slow and it doesn’t show up, and I miss it.  Cadences in the 75 to 100 rpm range seem to do the trick.   This sympathetic movement of the suspension *seems* to add something to my ability to put down power.  As if my legs feel fresher, with more snap.  Riding along recently I have devoted uncountable moments to unlocking the mechanism of it’s benefits, and I have come up with the following half-assed theory:   So, on a normal bike, the rider’s center of mass oscillates back and forth and from side to side as the legs do their thing.  The energy required to accelerate the COM does not efficiently come from the energy of deceleration, so this energy is lost to the rider’s body, to friction between the seat and the rider, into flexing the seat, manufacture of pixie dust, etc.  This may explain why overall cycling economy goes to hell as cadence goes way too high. Anyways, with a rear suspension available, some of that energy of deceleration is able to be rebounded by the suspension providing the acceleration of the next pedal stroke.  There is minimal damping in the suspension, so energy stored into the compression is, more or less, the same energy liberated on the extension.  Instead of the rider providing all the acceleration energy of each stroke, some of it is recycled from the previous one.

Is there any merit to this at all?  I have no idea.  Probably not, but it does remind me of the idea and practice behind the ERB, Energy Return Bicycle.  Check out the video in the link provided here and think on it.  Let me know what you think….

Ok, let’s get back on solid ground now, shall we?  The steering geometry includes a 70.5 degree head angle and, normally, this would makes for a pretty slow steering bike that isn’t much fun to ride and turns like a cargo ship, but that’s definitely not how the Moulton feels in practice.  I suspect the small wheels and a reasonable 55 mm of trail make the difference.  At low speed, there is no wheel flop or ‘hunting’ whatsoever, not even when climbing grades of the ‘friggin steep’ variety (18%+) .

However, that shallow steering angle along with a long-ish 42.5″ wheelbase (and amazing lateral and torsional rigidity of the space frame design, which keeps the wheels rigidly parallel) combine in a very good way to produce amazing stability at speed.  I haven’t experienced any shimmy yet either, something I cannot say about any bike I’ve ever spent significant time on.  I have even actively tried to induce it on a couple occasions and the bike seemed to say to me “what sort of stupid thing are you doing up there, fella!?” – it just wasn’t going to cooperate.

Similarly, when cornering at speed, the bike feels supremely solid.  I suspect the lateral rigidity of the frame and the suspension combine to produce this confident feeling by keep the wheels planted on the pavement and tracking in the exact same direction (hopefully one’s intended direction).

Versatility:   This is a bike that can be used for rando, general road riding, and loading touring.. so pretty much any paved road use except for racing.  It’s not really any good for non-pavement a beyond a smooth dirt road or rail trail, and the small wheels violate racing regulations, so that’s out anyways.

Moulton’s marketing puffery says the following about the TSR-30:

Perfect for day rides, audax and touring and excellent for fast road commuting. Available with carrier racks, bags and mudguards. Ride into the city, or load up and go wherever the road takes you.

This may be ad copy, but it’s pretty accurate (helps that’s it’s not overly flashy; it was probably written by the guy who brazes the bikes together or builds wheels all day long, not by a marketing department….).  Regarding loaded touring, you can get a rack from Moulton for both rear and front panniers, and the frame design pretty much invites things like strapping dry sacks directly to it.  And the massive clearance between saddle and rear wheel allows for even the most ginormous of seat bags.  Small wheels are very durable and reliable.  The bike comes with low gearing sufficient for riding fully laden in most terrain (about 25″; with it easily lowered to about 21″ with a cassette swap to a 29T large cog).

Aesthetics:  This is in the optical cortex of the beholder, but I think space frame Moultons are attractive.  They are unconventional, of course, but I think that’s what I like.  The bike does get noticed, particularly by kids, who seem to love the thing.  Adults probably notice it too, but they are too cool doing adult things and thinking adult thoughts to be mentally distracted by a primitive veloicpede-like object that happens to cross their field of vision.

Annoyances:  The TSR comes with two sets of water bottle cage bosses.  The one on the underside of the frame actually works, because you CAN get to it while riding (much to my surprise), but it’s too inconvenient to be the one you reach for repeatedly (I only use it when one bottle empties and I switch to the 2nd).  The set on the seat tube is very accessible, but I couldn’t get the inside of my knees to stop hitting it, and this was causing my knee pain as I would move my legs unnaturally to avoid it, so I had to punt, and figure something else out.  I ended up using a piece of rectangular aluminum bar to mount a cage off of the front rack frame mounts.  This works well, but sticks the bottle out in the wind.  I have a couple other ideas, but this will suffice for now.  I should note that if I ever want to use a front rack I won’t lose my bottle because there is a bottle cage mount integrated into the front pannier rack itself.  Pretty nifty.

The high gear is only about 98″.  I am happy with the 110-120″ high gear I have on most of my other bikes.  The consequence is that I don’t pedal above 30 mph or so.  Not a big deal, but I wouldn’t mind a higher gear.   The bike can’t accept much bigger chainrings than it has now  (58T), so if I want to change this, the only real solution would be something like a dual drive rear hub (which would be compatible with the Campag shifter or derailleur, and has high losses in the under- and over-drive modes)  OR a Capreo rear hub/cassette with a 9T small cog (but again, not compatible), OR a Schlumpf Speed Drive crank (which I don’t favor due to the losses in the over-drive mode, and wide Q factor).

Other Mods I’ve Made and Accessories:  I ditched the stock Schwalbe Durano tires after only a half dozen rides, since they ride like rocks.  The bike currently has some Panaracer Minit Lite PT’s.  These ride a lot nicer but they aren’t as puncture resistant, it seems  (got my first flat of the year a couple weeks ago with a bit of glass in the rear tire).  The manufacturer also did a terribly odd thing and put the logo and such on the tread of the tire.  Surprise!?!, it wears off quickly.  Why did they do that?

Since this bike will see nighttime riding duty in fall, winter, and spring, it’s been festooned it with Fiks reflective tape, and fitted with my B+M Ixon IQ headlight, and Dinotte 300R taillight.

Pics were taken with my Acorn medium saddlebag.  This bag is usually unnecessary during the summer, but for cold weather, and riding that transitions in or out of darkness requires a place to store reflective stuff, supplemental clothes, and spare batteries.

One modification I plan to make soon is to ditch the adjustable stem (actually good thing for Moulton to provide as original equipment) and get a fixed stem, along with a pair of Nitto Mod 177 Noodle bars in 44cm width. I don’t care for the modern compact drop Deda bars that came with the bike  (just a personal preference), and most adjustable stems are heavy and ugly (as this one kinda is).

Final Words:  Overall, this is a great bike.  It’s been worth every  penny.  The TSR series may not have the cache of one of the similar Bradford on Avon-built Moultons (like an AM), or the fancier front and/or rear suspension systems of a Jubilee or New Series, but I still think it’s pretty hot shit.  Hot shit that I can’t actually afford is cold shit to me.  Enough potty mouthing…. Look at some pictures, ok….

The TSR working on its tan.

Stronglight crank and BB.  Nice, but imagine my surprise when I found that it is proprietary in two (2!) senses ( first, the middle ring is a unique 130-110 BCD triplizer, and BB/crank interface, while ISIS type, has the left crankarm fixed to the spindle.  Where can I find a axle-less ISIS BB?  Nowhere.)  WTF.   Note: King Cage Iris on the underside of the frame and is super secure.  This is a top shelf product.

Italian Road Bike Mirror. This gets my seal of approval.

Fiks stickers on the head tube.  Homebrewed water bottle cage mount.  Moulton offers a beautifully fabricated version of this that costs over 100 USD.  My version cost 4 USD + 15 minutes of time.   Also note the carbon seatpost.  Imagine my surprise when I found it was a very obscure size – 31.6mm (not the semi-normal 31.8mm).  WTF.

Rear suspension elastomer  (sorry it’s out of focus).  Moulton refers to this as the ‘Monosphere’ rear suspension, which is a simple rubber spring, although quite cleverly, the cone shape provides for a rising rate.  On pricier Moultons, the rear suspension is their ‘Hydrolastic’ system, which is a combination of a rubber elastomer spring and hydraulic fluid damping.

Panaracer Minits Lite PT, with the tread-printed(!) logo half scrubbed.  More Fiks stickers on the fork.

Clearance for 33mm up front w/o fenders OR 28mm with fenders. (Rear is about the same).

View of handlebar with very clunky adjustable stem (I don’t like the use of the word ‘cockpit’ in this instance).  Imagine my surprise when I found the steerer is 1″ (not the modern standard of 1-1/8″). WTF.

One more glamour shot.

Links:

Moulton:  http://www.moultonbicycles.co.uk/

Moulton Bicycle Club’s summary of the TSR:  http://www.moultonbuzz.com/models/tsr/

Pashley:  http://www.pashley.co.uk/

Fiks Reflective:  http://www.ridewithfiks.com/

King Cage:  http://kingcage.com/

Italian RB Mirror:  http://www.avt.bike

Acorn Bags:  http://acorn-bag.myshopify.com/

B+M:  http://www.bumm.de/

Dinotte:  http://dinottelighting.com/

(…cork in handlebar…) Unibroue:  http://www.unibroue.com/en/home

Energy Return Bicycle (ERB):  http://www.erbbike.com/index-1.html

Double Pylon Review:  http://www.bikeradar.com/us/gear/category/bikes/road/product/review-moulton-twin-pylon-8878/

Jan Heine’s planing theories ‘explained’:   https://janheine.wordpress.com/2014/11/23/what-is-planing/

    and:  https://janheine.wordpress.com/2014/12/31/the-biomechanics-of-planing/

    and:  https://janheine.wordpress.com/2011/02/27/a-journey-of-discovery-part-5-frame-stiffness/

JH’s ‘work’ on suspension losses (replete with a some misguided Moulton bashing in the comments):  https://janheine.wordpress.com/2012/08/12/suspension-losses/