I have a 2009 Felt B16 Tri bike and had a few questions:
I just bought a new rear race wheel and don’t feel like swapping my rear cassette back and forth. I want a new rear cassette, but am thinking about changing to a different gearing ratio. Currently I have a Shimano 10-speed 12-25 tooth cassette. I am hoping to get more in my low gears to increase my climbing ability. what do you suggest? Also, I have a 105 geartrain… does it pay to upgrade to ultegra or dura-ace?
Lastly, I was looking at getting a new crank as well to help with my climbing ability. I currently have a FSA Gossamer TT Mega Exo aluminum 53/39 crank/chainset and again am looking for gearing to help with climbing…Any ideas? In addition, what are some good quality cranks at a good value that could replace mine? I love the Dura-Ace crank, but its quite expensive and i’m not sure its worth it.
One more thing… should I be replacing my chain with something better? I just have a stock Shimano chain that came with my bike and am thinking it’s due for replacement. If anything better than stock is needed, what should I be getting?
I have the same bike as you and am in The same dilemma too.
I am leaning towards 50 tooth and 38 tooth gears on the crank and a 12-27 or an 11-28 Ultegra cassette. This can be done for less than $200 in parts and doesn’t have to be done all at once either.
I thought of doing a compact crankset too, but having a choice of chainrings and cassettes could come in handy for different courses.
You can get 105 cassettes in the same gearing for $20 to $30 less but I bet the Ultegra cassette with an Ultegra chain later on might be worth it.
You can find online gearing calculators to crunch through all the numbers fairly easily. They don’t account for everything but it is helpful.
I found that the 11-28 cassette with the 50/38 chainrings allows for way easier climbs but keeps the potential speed of the 53/12 too. Of course I can’t pedal that hard yet.
what does that combo do? does it give you more high and low end? I was hoping to expand my gears since there is a few gears in my current set-up where I change gears and can’t even tell.
Does expanding gears cause issues with the derailleur skipping/missing?
50/38 chainrings seem rather strange for a road/TT bike.
It depends how much lower gearing you need. If you need to go real low, you can go with a compact crank (50/34) with a 12-25 to 12-27 or 11-28 (depends if you need that 16 tooth cog, which many like) As a point of reference, I use a compact 50/34 with a 12-27 on my road bike, but I use it exclusively in the mountains and do serious climbing. My tri bike is a standard 53/39 with 11-23 for flatter courses and an 11-28 for hilly courses like Wildflower.
Bonktown is throwing the SRAM Rival and Shimano Ultegra and 105 cranks up right now, keep your eyes peeled. The Rival and 105’s are going for around $110, the Ultegra was a little more.
A standard 53/39t has several duplicate gears. See below the GD (Gear distance: how far a pedal stroke moves the bike) for each GC (Gear combination). The compact gearing has a higher GD than a normal 53/12 and a lower (better climbing gear) than 39/23t. You could, of course, use a 12-27 or other higher spread, but you would then see massive differences in gearing from one gear to another.
A standard 53/39t has several duplicate gears. See below the GD (Gear distance: how far a pedal stroke moves the bike) for each GC (Gear combination). The compact gearing has a higher GD than a normal 53/12 and a lower (better climbing gear) than 39/23t. You could, of course, use a 12-27 or other higher spread, but you would then see massive differences in gearing from one gear to another.
So what type of set-up would you suggest to get more spread in the gearing, but not get stuck in a situation where one is to hard and the other is to easy?
I just picked up a brand new compact Rival crankset with bb for $89 shipped on fleabay and they had about 20 sets of them. Could probably dump your Gossamer for that and net a zero in the $ department.
I think there’s one other issue to consider in addition, is what gears you spend most of your time in and how changing ratios could affect that. With a 53T front, if you try to avoid using the 3 larger sprockets in the rear to maintain a good chainline, your minimum speed will be around 20mph depending on your typical cadence. Not a problem if you average 23+mph in a 40k or ride mostly flat courses. But if you have rolling hills or ride IM, or 70.3, then you may prefer a 50T to stay in the big ring most of the time… a 50/23 will allow you to ride down to around I think 17mph.
OTOH, with a strong tailwind, I think you could spin out a 50/12 at around 33mph. But again, unless your elite, that’s probably not an issue.
I had standard Ultegra 6700, stock on my '09 B12. I believe the cassette was 12-25. I swapped in a shimano RS compact crank (50/34) that I payed <$100 for, and an 11-26 ultegra cassette for another $60-70. I can hit 38-39mph before running out of gearing, and I can climb anything you’re likely to encounter at a cadence of >75.
Set up a spreadsheet and compare gear ratios of different setups. Some have large gaps, and the last thing you want is for one of those gaps to correlate to one of your cruising ratios. I had a 12-27 cassette with a gear jump that was centered right at the heart of my Z3 power. It’s more of a nuisance than a hindrance, but frustrating nonetheless.
Tables like that are pretty handy. It can also help convince some that unless you’re a pro or elite, in many cases, compact cranks make the most sense even on a TT bike. But it depends on personal preference, what range or RPM’s you find acceptable, cadence, terrain and power output. There’s a lot of factors involved.
The funny thing is, a lot of people won’t ride a compact (even though they should) because they claim they will spin out when descending. But, looking at the chart, you will spin out sooner on a 53/12 than a 50/11!
And to the OP: if no one has mentioned it, you should replace your chain if you haven’t done so in a while, especially if you get a new cassette &/or crank.
+1. While I have a standard crank on the TT bike, I eventually will replace it. My other bikes all have compacts (most often a 50x36, but I switch to a 34 for hilly rides) and 11x23 cassettes. I have an 11x29 for hilly rides. I prefer 11x21 cassettes, but since they’re not available in Ultegra or SRAM, I just use the 11x23 for daily riding.
n=1, but I’ve been happy with compact cranks + 11-28 cassette, gives a low gear of 34/28 which I like (and I do end up using sometimes). This is on my road bike. My TT bike has the same cassette, but with standard cranks. Not sure if I’d want compacts on there, as I’m not climbing as much on it.