Sunday, June 24, 2012

How Low Can I Go, Part II

A couple weeks ago I wrote about putting a 22T granny gear on my bike.  It is still taking me a while to get used to it as I now have to shift both front and rear derailleurs at the same time so that I am not just spinning when I drop into the tiny gear.  I've found that because of this, I use the granny gear less, but that it really does nicely lower my range.

One problem with this gear, also because the large difference in size between the granny and middle gear (38T), is that the chain will fall off the granny gear when I'm shifting down to it.  To stop this problem I bought a (34.9mm) N-Gear Jump Stop Chain Guide.  Because of the pulley near the bottom bracket for the front derailleur, I couldn't get it quite as far down as I would have wanted, but it does seem to have stopped the problem.




Chain-stop from the front.

Chain stop from the side

When I originally put the triple crank on the bike, I found that the chain actually fell off the crankset less frequently than with the original double. With the small granny gear, the problem was worse than with the original double.

In the same vein as the last post, I moved the seat on my Sofrider as far forward as possible as well as lowered the angle of the seat. Lowering the angle means I've reduced my cross section to the wind.  Moving the seat forwards means that hopefully my center of mass is now closer to the front wheel to help with wheel slippage when climbing.

You'd think that when somebody is writing about this in a blog called The Recumbent Quant, there would be a quantitative measurement about how much forward the seat has moved, or by how much the angle has changed.  Well, don't worry.  I'm disappointed in myself too for not having these things.  My guess is that the seat angle changed from 50 degrees to about 45 degrees.  Part of me would like to be able to lower the seat even more, but given that I use it to pull a trail-a-bike, I think this is about as low as it can go.

New seat position.  It few centimeters further forward and probably about 5 degrees more horizontal.

 I've been riding this way for about a week.  I guess the biggest surprise is that there really isn't much of a difference while riding.  The handlebars are further away and feel a bit less "cramped" (although it was never really a problem before) and the viewing angle to my bike computer is a bit worse.  And I had to extend the boom so the bottom bracket/crankset moved a bit more forward. So I can tell that the seat is in a different position, but the bike basically feels the same when I'm riding it.

Another possible difference is that by tilting the seat back, I'm able to ride further without "recumbutt" (which is having your butt fall asleep (this is much better than having your "what-what" fall asleep)..  This is a problem that I used to have on longer rides.  I haven't had any symptoms yet, but I've only ridden for just over 16 miles since I made the change.  I'll probably eventually add padding to the seat bottom as well.

I do feel as if I am cruising at a little faster on flat terrain and on my maiden voyage, I hit 39 mph on a course that I've ridden on before without realizing I got anywhere near that fast.  And the next day was my fastest every time commuting to work.  All of that being said, I'm not really yet convinced how much of a difference it has made (although it's pretty clear that it hasn't gotten any worse).  Time will tell.

Saturday, June 9, 2012

How Low Can I Go?

When I bought my Cruzbike Sofrider, it came with double front crank (with 48 teeth on the big cog and 34 teeth (48T/34T)) and a rear cassette that goes from 11T to 32T.  With this setup, the bike has a range of 26 to 107 gear inches.  (For those unfamiliar, "gear inch" refers to equivalent size wheel without any additional gearing.  For example, 60 gear inches is equivalent to riding a large penny-farthing bicycle with a 60" front wheel).

Almost immediately I realized I wanted more range and although it took me twoattempts, I installed a triple crankset (48T/38T/28T).  This decreased the low end of my gearing to 21.5 gear inches.  This was a big improvement and made a big difference, both when pulling a trailer on "regular" hills and when riding solo up very large hills. It was a big improvement, but it wasn't enough.

After the Bloomin' Metric Century and the problem I had on that large hill, I started thinking about what I wanted to do.  After asking on the 'Bent Riders Online forum and deciding that it was at least worth trying, I ordered a 22T cog.  This is equivalent to just below 17 gear inches (or a reduction of a third over the original crankset in terms of number of teeth or gear inches).

Today, I pulled the crankset, removed the old cog and put on the new one.

Crankset with the original 28T granny gear.

Crankset with the new 22T granny gear with the original gear to the right.  The new gear really does look a loot smaller, doesn't it.












My bike being held on the bike stand after reattaching the crank.

After taking it for a short test drive, I realized I needed to shorten the chain.  The reason is that the diameter of the 22T cog is significantly smaller than the 28T cog and that the chain was too long to be in the small front cog and the higher (meaning smaller in number of teeth and therefore also diameter) gears.

I ended up removing a couple more links than I meant to because the first time I pushed the pin out of the chain, I pushed it completely out and wasn't able to get it back in.  After reading online, I realized my mistake and made sure to leave the pin in the second time.  I had to break the chain one more time (again, I was smart and careful enough to leave the pin in) because I hadn't routed the chain correctly through the rear derailleur.

Here I'm using the chain-breaking tool.  I recommend removing the wheel before trying this.















The second time I was smart enough to leave the pin in and not push it completely out. The white bag is being held by my daughter so the camera phone would focus on the pin and not the floor.



















With the new setup, I can still (barely) make it into the large cog on the crankset and the largest (lowest) cog on the rear cassette.  You're not supposed to use this gear and I tried to avoid it before, but I'll try harder now.  I can be in the granny gear on the crankset and easily make it to the 5th gear on the cassette.  I can make it into the 6th gear, but it isn't entirely happy.

Since I had installed a new granny gear, I needed hills on which to try it out. After putting the kids to bed, I took the bike out for an 11 mile ride that went up Flax Hill road (one of the worst hills around here) twice.  I averaged 14 mph, which is my fastest ride (over 10 miles) ever.  Not bad considering I did Flax Hill twice.

I like the lower granny gear, but the difference between the medium cog on the crankset (38T) and this gear (22T) is quite noticeable.  When changing from the second cog to the granny, I also need to move the rear derailleur from the 1st (biggest) gear to 4th or 5th gear if I don't want to spin out (meaning spinning but not turning the wheel because it's moving too quickly).  I had similar problems when shifting out of the granny gear and if I didn't change from a high rear gear (say, 5th) in the granny gear to a much lower rear gear for the middle cog on the crankset, I found that it was too hard to peddle.

The first time I went of Flax Hill road, I did use the smallest gear on the bike, but found that I didn't really need to (the GPS claims my speed was as low as 3.6 mph here).  The second time I went up the hill, I found the lowest gear quite comfortable although for that particular hill, I would have been quite o.k. in the next highest gear.   Here the GPS doesn't report as low a speed, it does show me averaging 4.5 MPH for most of the last part of the hill,

For now, I think I'll go up a size to the 24T ring as the granny gear on the crankset.  In the future, I'll consider replacing the middle 38T chanring with something smaller (say, a 34T).  Definitely learned a lot playing with this.  More tweaking coming soon.

Sunday, June 3, 2012

Housatonic Rail-Trail

A friend of mine, Oguz, recommended the Housatonic Rail Trail (part of the Pequonnock Valley Greenway) as a nice place to take the family to ride.  So I folded up the trail-a-bike and the trailer and put them in the back of the wagon, put the bike rack and the two adult bikes on the car, and away we went.  (O.k.  It took a bit longer than I made it sound, but let's not dwell on how slowly I pack cars...)

The link above shows parking around here, so that's where we went.  When we got there, we found something like a parking lot that was full.  We found a spot and only realized later when we came back and was the only car parked where we were that we saw the sign saying we had parked in a tow away zone (our car was still there with no problems).

The area was beautiful with great tree coverage for almost the the entire ride.  The downside of great tree coverage is that it messes with the GPS ability to get a signal, so the route it traced out is somewhat deficient.  But that's a trade-off I'll gladly make.

Where we parked was basically in the middle of the trail, so we randomly decided to start by going south.  The trail is mostly paved although it's almost gravel in some places (but I had no problems with traction or pulling the big monkey on the trail-a-bike) and it was pretty much a soft decent until the end of the trail.  If we do it again, we'll give serious thoughts to driving to the end of the trail and parking on the street (I saw cars parked here).  I personally like to start at the bottom so I can end at the bottom of a big hill.

We turns around heading north, rode back to our car, got some food and kept going north.  About a mile north of our car, we saw picnic tables (and restrooms), so we stopped and had lunch.  (Or, well, we didn't really pack lunch, so we had chips and pears).  They also have parking here (more so than where we had parked), so this is another viable choice for starting the ride as well.

The view of the river from our picnic table.


Kate and the monkeys looking at (but mostly not falling into) the river.

The river and the trail on which we had ridden.\

The monkeys posing in front of the bikes.

The monkeys and me.

After lunch, we kept going north for a bit longer.   Somewhere around 6.5 total miles into the ride, we had a choice on the trail to take what I thought was a fork right or keep on the main trail left.  We stayed left, but then we soon ended up right next to an apartment complex.  I'm not sure if the path kept on going at that point or not because we turned around and went back to the car.

The trail was pretty busy today.  Lots of people walking pushing strollers and walking their dogs.  Many others out on bikes.  But there were no problems either safely passing people or safely being past by other bicyclists.  It was narrow in places and there were certain segments that I wouldn't have been as happy riding if it had been raining, but today there were no issues.

When we got to the car, the big monkey was quite tired as she really had pedaled most (or at least a lot) of the way.  The little monkey was a lot more energetic as he just sits and watches his mom pedal him up the hills.  When we were almost ready to leave, we heard that somebody on the trail was having trouble and that an ambulance was on the way.  We watched as they very slowly removed the car blocks on the path.  I certainly hope whomever was waiting for them was stable, because that was not the demonstration of speed or hurriedness that I would have hoped for in a true emergency.

It took us a little bit longer to pack the car than we would have liked, didn't quite have the right food for lunch, etc.  But none of that mattered today.  Oguz was right.  This is a lovely place to take the family for a ride and we all had a wonderful time.