Bicycle Mechanics - Jamis Coda Comp Gears vs Jamis Aurora Elite

Hey guys, in 2009 I got into biking and bought my first bike, a 2010 Jamis Coda Comp. After about 1,500 miles and really learning what it is I wanted to do I discovered that I really enjoyed long rides and sometimes packing the bike down. Essentially doing a little more "short touring" while doing some long commuting as well.

Because of this, I test rode a few different touring bikes, read lots of reviews and finally decided on the Jamis Aurora Elite. Partially because of a great price, 1,2500 for a 2010 model, a few good reviews and having a relationship with the shop.

I would not say by any means I am someone who truly understands bikes, but feel like slowly I am starting to have a better grasp of bike mechanics and specs. After logging about a hundred miles on the new bike I am starting to notice some differences. The question I have is I feel like my new bike coming down the hills is not geared the same and I am noticing or "think" I am noticing my high end gears are obviously not the same. I also am noticing it a little when I am coming from a stop or trying to get to top end on the flats.

The specs on the Auro Elite are - Cassette- SRAM PG-1050, 10-speed, 11-32T and a crankset - FSA Gossamer Compact, 50/34T, 170mm (47/50), 172.5mm (53/55), 175mm (57/59/62)

The Coda Comp has Cassette - SRAM PowerGlide 950, 9-speed, 11-32T and for the crankset FSA Alpha Drive with Power Drive, 48/36/26T, 170mm (15-17”), 175mm (19-23”).

SO my questions are, am I correct in my gut feeling and what could I do to improve this top end and what could I look to spend to do it?

Thanks so much for taking the time to read all of this, had no intentions of it getting so long.

How long are the crank arms on the new bike?

Old Bike 48-36-26
New Bike 50-34

New bike should be the fastest down hill and on a flat road.
Pedal faster.

I believe 170 mm, would that make sense? Also, I forgot to mention I am 6'5 and bought a 62cm. I ride a lot of hills and highway in southwest IA.

I believe 170 mm, would that make sense? Also, I forgot to mention I am 6'5 and bought a 62cm. I ride a lot of hills and highway in southwest IA.

Look on ther back side of the crank arms. 175mm my guess?

You're correct. 175mm

What were the cranks arms on the old bike?

It was also 175mm.

Are you saying your new bike is slower of the two?
Do you have a bike computer to show your speed?

I do have a bike computer, and my new bike seems to be a bit slower. I notice it mostly coming down hills and as I really crank on it when I am trying to get to top speed. Looking at my gears, does this not seem right? Have I just gotten that much slower over the winter?

Wider softer tires can make one slower.
Are your brakes rubbing the wheels?

The Aurora will feel slower than the Coda, more relaxed head tube angle (72.5 vs 72), and fatter tyres (32mm vs 28), but should be more comfortable over long (1-200km+) rides.

Both look like good bikes, would look at the Coda as a communter / short run(up to 50km) bikes the Aurora as the long haul bike.

If you are going touring, t's not all about speed, comfort is a big factor, and if you start to change things on the Aurora, you may loose come comfort

What happens to feel of speed when the bikes are fully loaded?

Jim, I haven't gotten the chance to get it fully loaded yet (hoping to in the next two weeks). You're right though, the reason I did buy it was to be a bit more relaxed and to be able to load it down. Being somewhat new to bikes I knew I'd see some difference, it just caught me off guard on my first few 30 mile commutes/rides.

I guess the question I was asking myself as I rode it was, could I get that top end gear for when I wanted to really get after it, without sacrificing any of my comfort/ability to load down.

The gearing says you should be able to go faster on the Aurora, but I doubt you will due to the tires. don't worry about that, as the difference will not be much; and fully loaded you would only see it on gravity assisted decents.

For your Aurora, make sure you get out and bed the brakes before doing lots of riding on it, as it will make the pads last, and feel better under breaking (modulation)

The high gear on the elite is 50x11 and is higher than the coda 48x11. The only way to get a higher gear is to go with a standard road crankset with 53/39.

The real question is are you spinning out the 50x11 gear? If that is the case then it is time to start coasting down some of these hills.

At 50x11 with a cadence of 90 rpm your speed is about 33 mph
a 53x11 with a cadence of 90 rpm is 35 mph
and you coda 48x11 with the same cadence is 31 mph.

The only way to increase the top speed per revolution is to get a larger chainring or increase your cadence.
the other option may be to use tires that have less rolling resistance (higher pressures and better rubber (maybe?)).

I know when I got my touring bike it felt slow and slugish. This difference is due to my previous bikes being mostly road bikes with narrower tires, higher tire pressures, higher or similar gearing (since some of my road bike have compact geometry), frame weight and tighter frame geometry. Mostly the tire pressure and diameter makes the bike feel slower.

I guess what I am saying is that you are precieving that the elite is slower but in based on mechanics it isn't. And there isn't a worthwhile way to get higher top end speed.