jbeck

Question if you buy a new crankset do you also have to change out the cassette to match it? Also I currently have a crank with 3 high gears, I see some good deals on ones with 2. How will this effect the ride besides the number of gears. Last is how do I figure out the size I would need? Thanks for your help.

- Joe

CACycling

Not enough info to even begin. How many teeth on your current chainrings? How many teeth on the ones ou are looking at? How many cogs on your cassette? What is the range on your current cassette? What type of shifters? What are you trying to achieve by changing cranksets? What kind of riding do you do? What kind of bike?

Al1943

Once you've learned to count teeth, find the steepest and longest hill you want to be able to ride up and then find the gear combination that lets you ride up at a reasonable cadence (crankset rpm). And climb that hill when you are tired.
This will help you understand what your particular gearing needs are. It is not possible for someone on the net to tell you what you should buy without knowing what you need.
It is not necessary to change the cassette when changing the crankset.

mulveyr 

I'm assuming that when you sat you have "3 high gears", you mean than you have a triple; Three chainrings. Triples, as you note, give you more gear options ( but not a third as many more, because you don't want to ride in the large/large small/small combination ). Generally, triples will have a smaller granny-gear than a Road double, which is handy when you're climbing hills.

As for figuring out what you need... well, what do you use the bike for? For example, I just swapped out my 50/39/30 cranks on my touring bike for a 44/32/22 set, because I'm old, fat, slow, and like it that way. :-) For commuting, unless you're climbing the Rockies to and from work, that's most likely too low. A fit recreational/racer would fall over laughing, too.

So the first thing is to explain is what you want to use the bike for.

Next, there may ( or may not ) be additional parts you'll need. Bottom brackets, for example, come in a variety of types and sizes. You'll need one that goes along with your crankset. In the case of systems like Shimano's HollowTech, the BB is effectively part of the crankset and will come with it. In my case, I went from a Shimano Octalink BB/crank to a HollowTech one, which also required a bit of simple machining ( which any good bike shop can do ) called "facing and chasing". Thankfully, all of this is cheap - my LBS charged me $32 for the machining and swapping out the cranks.

jbeck

Wow, yes I still have a lot to learn . I am new to road biking and with my full-suspension mountain bike I always just took it to the shop and got upgrades. Have spent a fortune on my MTB at the shops so trying to learn to do things myself.

I purchased a fairly cheap bike online for commuting to and from work. I am fit run multiple marathons a year and started to get tired of running every day so I decided to get a road bike. Very impulsive purchase. Part of the goal is learning how to work on the bike myself. I will commute 32 miles round trip at least 3 days a week if not everyday and want to do some century rides as well as sprint triathlons. I just signed up for my 1st sprint so I also need to get some swimming training in. I still love running and will continue to run in the evenings.

Here is what I have noticed right away riding the bike. I think the crank feels like it sucks, as well as the tires, brakes and possibly rims. This compares to what I feel while riding a my mountain bike.

Here is what I have:
Front and Rear Derailleur: Shimano 105 5600 for 30 speed
Shifters: 105 Integrated STI 10 Speed
Cassette/Freewheel: Shimano 105 HG5600 10 Speed Cassette 12-25T (looks like I don't have to change the Cassete)
Chain: Shimano CN5600 HG 10 Speed
Crank: FSA Aluminum Alloy arms, Triple 50/39/30T Black Finish

What I want to do is change the crank out to match the rest of the Shimano components. I don't know it just does not feel right to me.

bikinfool

Like the others say, kinda hard to know specifically what you're talking about without more details about the current bike and cranks and what you're considering. Likely the cassette is fine (or is it worn?).

One slight correction to Mulveyr's comments on Hollowtech. Hollowtech referred originally to the crank arm construction. Hollowtech I cranks didn't come with the bottom bracket (but you did need to buy the type and spindle length of cartridge Octalink bottom bracket that matched). Hollowtech II is the current generation of external bottom bracket type cranks and the bottom bracket bearings do come with the crank (as the spindle is incorporated into the crank itself). Shimano probably should have come up with a different name when they went to the external type (but it really referred to the crank arm construction so it did make some sense). Probably more than you wanted to know....

jbeck

Oh and this is one of the cranks I was briefly looking at. Seems like a good deal, plus I have an additional discount I can use there that knocks of quite a bit more. Also looks like the bike shop I take my mountain bike to has some Shimano 105 cranks on sale. Anyone recommend a good book on working on bikes? Be fun to build one from frame up at some point in my life and also understand more what you guys are saying.
https://www.sierratradingpost.com/p/,...-Crankset.html

bikinfool

I like the Zinn books (Zinn and the Art of, has both mountain and road versions). Reading up here and sheldonbrown.com and parktool.com can be very helpful, too.

Not a lot of magic in a crank. Don't know if what you're feeling between a fs mountain bike and a road bike is too comparable, either. That's a lot sucking going on with the new bike which I'd say is more just the different type of bike and riding for now; when I ride my road bike a lot during winter due to trail conditions and then jump on my mountain bike it takes a while to make the transition to the different bike and riding.

You don't need a triple chainring on your road bike necessarily, but that would depend on the terrain you ride to an extent. The middle and large chainrings on your current crank aren't that much different from the double you're considering. I'd go 105 cranks over Dura Ace unless you just like spending money. FSA uses the same design as Shimano for the external type bearing cranks in any case.

How in heck you can tell a rim sucks I don't know (or do you mean wheel?). Going from disc brakes on your mountain bike (assuming) to rim brakes might feel weird. Tires on stock bikes often suck.

jbeck

BikinFool, Thanks for the responses. Helping me think this out. I just looked up the tires Michelin Dynamic 700x23. Your right I should ride it more and get use to the bike. The issues I was was feeling with the tires/rim was they didn't seem to handle hitting cracks and rough patches on the road very well. Having full suspension for the last 5 years definitely probably makes it feel a bit more off. I felt like they were going to bend on me or maybe I was just worried they were. I was trying to avoid these obstacles but is seems the bike lanes in SD are not all in the best of shape. With the crank I just read a bit more into it, it is possible my mountain bike crank is a different size than my road bike, giving it a different feel. I'll check out that book. I need to learn the overall mechanics of a bike and it's components and that will give me a better overall understanding. No I am not looking to just spend money, I just want a smooth fast ride.

CACycling

Other than aesthetics, there is no reason to change anything that isn't broken at this point. My guess is you need to tune up, and possibly lube up, your bike to get everything running right. Make sure your tires are up near max PSI and start riding. After you get some miles under your belt and do some reading up on all things cycling, you'll have a better idea of what set up makes sense for you and the way you ride.

Once you get it all figured out, then you can look for specific upgrades that make sense. Even upgrades for aesthetics make more sense if you are installing stuff that works at least as well for you as what you are replacing.

cny-bikeman

If you purchased a bike online it needs to have a competent tuneup, meaning not just twiddling a few screws and squirting a bit of lube here and there. HIGHLY likely that the bearings, esp hubs, are adjusted too tight and that cables need lubrication, etc. Any bike shop doing a proper full tuneup with truing should be charging in the $40 and up neighborhood, mostly up.

Al1943

If you are more use to a mountain bike and are now trying to adjust to a road bike the first thing you need to be aware of is the loss of tire pressure overnight. With high pressure road tires you will need to pump them up before each ride or once a day. This will make a huge difference in performance.

Drew Eckhardt 

It does give you more options even if you don't need the range.

For instance, I used to ride 50-40-30 x 13-14-15-16-17-18-19-21 in the Colorado Rocky Mountains. A comfortable cog to cruise in on flattish terrain is somewhere between a 16 and 19, and the biggest change in effort to maintain the same cadence in that range is about 13%.

To get a similar low gear with a 53-39, I'd have needed a 13-14-16-18-20-22-25-28 cassette. A comfortable cruising range would be between a 20 and 17 cog; although two tooth jumps it's a 27% effort increase at the same cadence dropping from an 18 to 16.

I like the one tooth jumps a lot. While it doesn't make a big difference in power output, it feels easier so going faster is more comfortable.

It's not as bad with 9 or 10 cogs in back and the bigger 50-34 jump vs. 52-42, although with a tight cassette there's a lot less overlap so you shift the front more than on a triple, it doesn't shift as fast as the triple due to the bigger difference, and chain rub is more likely (I had no usable overlap without rub until I shimmed the chain rings on my 50-34 x 13-23 9 speed setuop).

RT

If your only goal is to achieve a double, you remove your inner chanring and you have your compact double. If you want to switch in order to get a larger big ring, either buy chanrings and swap them out, or get a new crank. I don't see the need for more than a 50-39 for your application. Am I missing something?

EDIT: Is this a Windsor Fens?

jbeck

I had no idea. I had the bike sitting for a couple days. Checked this morning before my 2nd commute and the tires were at 80psi, pumped them up to 105 (has a 116 max) this made a huge difference. Much smoother and faster. I also raised the seat post up a bit and that helped the pedaling feel more smooth.

Toddorado: Yes it is a Windsor fens