Bahumbug7

I am a total noob! Not new to bikes but new to forums. My wife and I have been riding bikes for a number of years on rail trails and hard-pack with some hills. We have been doing alot of riding now in urban areas. My wife and I both are in our 50's so our riding is not extremely aggressive. The bikes we have been riding are mountain bike build ups that I have done myself. They have performed well, but I am geting the itch to build some new bikes that will be better suited to our riding. My research has taken me to a point that I need some help with. I plan on building up an aluminum cyclo-cross frame with a solid carbon fiber fork that will receive a mountain style stem. But I am not certain about the gearing. I have looked at the good old derailleur system but am also reading alot about the inner hub gearing systems including the newer CVP types. Any opinions on these systems? does anyone out there have a preference to a road set-up vs a mtb set-up for riding both rail trails and pavement with some hills, but not often?

Bahumbug7

ok...not much response to that!! Maybe I'm posting in the wrong place, but, I'll continue...I've scrapped the inner hub gearing for the standard derailleur system anyway. Another question arises though on the build. I am looking at a Shimano FC-5600 crankset and wanted to know if there are any opinions on this crankset for the intended use of rail trails, dirt roads, and pavement riding and/or if there is a better suggestion for a two ring crankset for this purpose.

clarkbre

I assume you are looking at this crankset:

Shimano 105 Double Crankset

If so, I don't think I would use it on a rail trail/dirt road/pavement bike.

While it is a good quality crankset, I think it is geared too high for your intended purposes. The final gearing would end up being more like a '70's 10 speed than a modern road, hybrid, or mountain bike. 39T for your smallest chainring would certainly be doable but it seems the normal standard these days is to run a 50 & 34T chainring. Unless, you're running an 11x34 cassette, your lowest gear will be too high for what is needed.

A couple questions I have for you are:
1. What cassette are you planning to use?
2. Have you looked at Sheldon Brown's Gear Calculator to determine what gear inches your newly built bike will have?
Gear Calculator

Bahumbug7

clarkbre...thanks for the feedback. In answer to your questions
1) I haven't fully determined the cassette to use yet. I do know that when my wife and I ride we don't do alot of shifting between gears. Only when we come across a hill (which is occasional at best) is there a need to shift alot. I have a fuji hybrid now that includes a 7 speed cassette that is an 11x36. This gives me a really low gear for hills and seems to be the only time I am using that sprocket. But it has 3 chain rings up front so it has more gearing than I really need. Just getting into the meat of this subject myself so can't answer the question fully.
2) It's funny you mentioned Sheldon Browns site. I was just on it this morning looking at his tables and calculator for gearing and such. I'll know more as I better understand the "science" of gearing and

Bahumbug7

...and gearing components.

Also, I am doing the build up because it is fun for me to do. Don't really need to know all this technical stuff other than if i'm building a bike, why not build the optimum bike for me?!

Any thoughts and or opinions are greatly appreciated as I think this thing thru.

Bahumbug7

not getting much feedback here but I'll keep looking for info. I've got the cyclocross frame and am now looking for tires and wheels. Problem I'm having is the info on tires and wheels is confusing. If I'm going to ride streets and rail trails, it seems that full cyclocross tires are too wide where as road tires are too narrow. So, trying to decide between recommendations for 29'ers, 700's, blah, blah, blah is becoming challenging. I am looking for some feedback, opinions on wheel and tire sizes for a cyclocross frame that is suitable for the rail trail type riding but is also useful on the streets. Mind y'all I am not a racer, but ride in the various trail/surface conditions often.

clarkbre

700x32c

corwin1968

If I was building up another bike and was set on a double, I would look at Rivendell Bicycle Works' Sugino double crankset. It's something like 40/24 which gives a decent large ring for going fast and a good granny ring for hills/dirt/headwinds.

Bahumbug7

700 x 32c compares to a 1-1/4" width. Yes? I see that size often. Is it the norm?

Bahumbug7

I have not got the crankset yet, but Clarkbre's suggestion of the 50x34 seems to be a good range. I'll look into the Sugino you have suggested. If I go with the double (which I probably will) does a 8 or 9 cassette still work? I'm seeing I need to pay attention to the space between hi & lo sprockets more.

clarkbre

In all honesty, it sounds like you need to blueprint your future bike. Answer some critical questions and then start planning around the answers. You've told us you want to do some rail/trail and street riding and that you have an older cyclocross frame to build around. Perfect.

What wheel/tires size to run?
Run a set of 700c (622mm) wheels in the 15mm to 20mm width. For general use, 32 or 36 spoke wheels will be fine.
A good all-round tire size for rails/trails & road will be 700cx32mm. It's wide enough for comfort and light rough terrain yet narrow enough to run at a high pressure with low resistance on the street.

What cassette, crank, derailleurs & how many speeds?
Pick this question apart.

1. Analyze what terrain you will be riding on. Is it all relatively flat, steep hills, or rolling hills? Generally the flatter an area the less gear range you will need. I find a range of 30-90 gear inches on my hybrid is more than adequate and I ride a lot of hills.

2. How many gears do you need? Is more better or is simplicity bliss? You could go as simple as a 1x7 set up or as complicated as a 3x10.

3. How close do you want the gear steps to be? Slightly different or huge jumps? Close gear ratios are nice to maintain a specific cadence but the large steps are ok if you are keeping it simple and just out to enjoy the ride.

Once these are answered, you can start researching what parts will work with what. To start, focus on the number of speeds and what cassette/crank combination it will take to stay within the gear inch range. After that, figure out the proper front and rear derailleurs and shifters.

Sorry this is vague but these are the steps I've taken in building a few bikes. The outcome has been good and only needed minor adjustments.

corwin1968

I went thru the process you are currently engaged in and I spent a lot of time running gearing calculations on Sheldon Brown's website. I would suggest figuring out the gearing on your current bikes (ie, number of teeth on each chainring and number of teeth on each cog) and plug the information into the calculator. Then pay attention to what combinations you normally ride in and take note of where you feel like shifting makes almost no difference, where it feels like there's a huge jump between two gears, where you feel you need more gearing range, ditto for less gearing range. Figure out exactly what high gear you want, what low gear you want and how big you want the jumps between each gear to be. You can can then customize your crankset/cassette combo to your chosen specifications. It sounds complicated but it's really very simple once you start playing around with the calculator. I think this is the THE most important thing you can do on your builds. I don't think anyone can ever be truly satisfied with a bike where the gearing range doesn't suit them. To me, a compact road double (the 50/34) you mentioned is too high for most recreational riders. The 50 is higher than most will ever need and the 39 is not low enough for most of us, if we ride any hills, are heavy (or carry a load) or live in a windy location.

I chose a Deore triple with 48/36/26 chainrings and an 11-28 9-speed cassette. This gives me a very broad range of gears with reasonable jumps between them.

Here is the link to the calculator: https://sheldonbrown.com/gears/

Bahumbug7

Guys...this info is awesome! And will definitely help with the build. Thank you very much. I will consider all the questions as I build this bike. And, I will continue to post when I have more questions. But, here's another one. I have a mechanical disk brake set that I would like to use, but they are for an MTB set-up. So, can you get 700 wheel sets with mountain hubs? Are 29'ers and 700's the same? According to Sheldon Brown, they are. Any insight on this?

fire

+1.
I run 25 rear and 32 front on my "rails to trails bike", now. It gives slightly more cushioning on the front and still allows me to ride on occasional hard packed limestone if necessary.

kingsqueak

Yup you can, most prebuilt disc wheel sets are heavier mountain rims. The difference is rim width and how heavy they are for mountain 29er vs 700 road. Also the hub width for frame and fork spacing varies.

clarkbre

Bahhumbug7- What Cyclocross frame are you using? Does it have the tabs for disc brakes?

Bahumbug7

Yes it has the tabs. The forks do also

Bahumbug7

Corwin1968 - did you put together the 48-36-26 chainring set-up yourself?

fietsbob

The Bike Biz having so many different sectors And Niches, now there is no Broadly drefined Normal .

only personal Preferences .. for a given bike type Hybrids as a category
fall in the middle between Road bike skinny and 29er fat
so 32 ~40 is the usual Range ..

Bahumbug7

fietsbob & clarkbre - so if I'm looking for a ride that does well on the flats including trail & road and will get me thru some mud and/or small bumps, in your opinions, I'm looking at something like 700c wheels that are from 15-20mm and tires that are 32c's. What is the reason for running a narrower tire in the back?

Bahumbug7

sorry...after more research, I've found this chain-ring set up readily available.

clarkbre

I have no idea. I personally run the same size/type tire front and rear each of my bikes.

And, yes, a 700c wheel 15-20mm wide with a 700x32c tire will work well for you.

Wanderer

Just more opinions........ I run a 40 on the rear for added comfort, and added capacity. It rides as nice as a 45-47.. I also run a 35 on the front, to quicken the steering, and make it more maneuverable. Running a 35 on the rear is noticeably more harsh. Running a 40 on the front doesn't do anything to improve quickness and steering like the 35. Running a 35 on the front, is as comfortable as it was with 45s there. I run my Schwalbe Marathon Supremes at 92 PSI, because that's where they roll the best. Below that is more work, and above that improves nothing.

The wider the tire, the better, for off pavement use. It's just a matter of finding what you are willing to settle for, and what works the best for you.

Thees Supremes are really bad in ice and snow, so I don't ride that stuff. I just move to the Beast in the basement during the winter. They are great, for anything else.

My mix improves my speed, handling, quickness, and ride - over the 45s which came OEM. Having all of the different sizes available at the same time, allowed me to settle on these by trial and error. I will always use this mix, whenever they will fit.

I ride a mix of streets, roads, paved and unpaved MUPs, and occasional gravel roads. Mosty semi flat, but I do live in a big river valley, so there are some nasty hills in there. I also ride a 48,36,26, with a 9 spd 11-34, which will handle just about anything. I think a 50,40,30, would be a perfect crank for me, as I ride mostly in the middle ring.. I try to do 30-40 miles every day.

Bahumbug7

I ride a mix of streets, roads, paved and unpaved MUPs, and occasional gravel roads. Mosty semi flat, but I do live in a big river valley, so there are some nasty hills in there. I also ride a 48,36,26, with a 9 spd 11-34, which will handle just about anything. I think a 50,40,30, would be a perfect crank for me, as I ride mostly in the middle ring.. I try to do 30-40 miles every day.[/QUOTE]

I'm starting to lean more towards the 48-36-26 set up also. As i run the calculator I'm finding that with my riding style and the type of riding I do, this configuration is better suited for me. I am also finding that and 8 or 9 spd 11-34/36 will also work as well, with not a whole lot of difference between the two other than the extra sprocket.

Bahumbug7

[QUOTE=Wanderer;16198384]Just more opinions........ I run a 40 on the rear for added comfort, and added capacity. It rides as nice as a 45-47.. I also run a 35 on the front, to quicken the steering, and make it more maneuverable. Running a 35 on the rear is noticeably more harsh. Running a 40 on the front doesn't do anything to improve quickness and steering like the 35. Running a 35 on the front, is as comfortable as it was with 45s there. I run my Schwalbe Marathon Supremes at 92 PSI, because that's where they roll the best. Below that is more work, and above that improves nothing. [Quote]

Also, with the tire set-up of 40 rear and 35 front are your wheels 700C and 15-20 mm wide?