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-   -   Best way to improve climbing -- change crankset? (https://www.bikeforums.net/showthread.php?t=1235022)

san_antone_rose 07-19-21 01:13 PM

Best way to improve climbing -- change crankset?
 
Hey y'all, I've been riding for about a month a mid-90s Kestrel 200 SCI which has the original 105 groupset in really nice shape. Thing is, I live in a pretty hilly city and the 42/53 chainrings make climbs a real PITA. The rear combo (7-speed) is 11/13/15/17/19/21/23.

I'm wondering what the best way to get some better climbing action is, and I've kicked around the idea of swapping the old crankset for a newer 105 one with 34/50 chainrings. Any thoughts on this idea? Looking for a solution that's neither outrageously expensive or complicated. Mostly ride around the city and on paved trails so no racing-level performance required.

dsbrantjr 07-19-21 01:27 PM

Replacing the cassette with a 11, 12, 13, or 14 to 28 (14 to 28 would be my choice, I can't push 53x11) one would give you a ~20% lower low gear. You will probably need a new chain but I believe most 105 derailleurs will accommodate the 28T large cog.

Unca_Sam 07-19-21 01:29 PM


Originally Posted by san_antone_rose (Post 22148596)
Hey y'all, I've been riding for about a month a mid-90s Kestrel 200 SCI which has the original 105 groupset in really nice shape. Thing is, I live in a pretty hilly city and the 42/53 chainrings make climbs a real PITA. The rear combo (7-speed) is 11/13/15/17/19/21/23.

I'm wondering what the best way to get some better climbing action is, and I've kicked around the idea of swapping the old crankset for a newer 105 one with 34/50 chainrings. Any thoughts on this idea? Looking for a solution that's neither outrageously expensive or complicated. Mostly ride around the city and on paved trails so no racing-level performance required.

Your best bet isn't to do the crankset, it's to do the rear cassette/freewheel. You can find new 7 speed cassettes that should fit a UG/HG freehub body on your wheel with a large cog of 28-30 teeth.
The downside to this change is that you might not have the right cruising gear anymore, but the cassettes are easy enough to customize. Your RD might have a max cog of 28T, or not. "mid 90's" 105 is unfortunately not descriptive enough, but Shimano keeps ALL of their technical documents available online. See if you can find an EV of your RD to visually match, and go to the installation manual to get Max Cog and Max difference for it.

Eric F 07-19-21 01:46 PM

Even when I was a very strong and fit racer-boy (a very long time ago), I wouldn't want a 42x23 as my lowest gear for general riding/training. That's not much of a low gear. A 50/34 up front with an 11-28 cassette would be a dramatic change of gearing that would probably make things much more enjoyable. However, this might open up a bigger can of worms if your rear derailleur can't handle that much range.

shelbyfv 07-19-21 01:48 PM

I'd go with a Sora 9 speed 50-34 over current 11 speed 105. It's more likely to be compatible with your 7 speed but still uses the nice HT2 bottom bracket. You get modern components and lose a useless 53t crank. You can do the cassette later if you need to.

https://cimg5.ibsrv.net/gimg/bikefor...58ddf71ed5.png

san_antone_rose 07-19-21 01:54 PM


Originally Posted by Unca_Sam (Post 22148626)
Your best bet isn't to do the crankset, it's to do the rear cassette/freewheel. You can find new 7 speed cassettes that should fit a UG/HG freehub body on your wheel with a large cog of 28-30 teeth.
The downside to this change is that you might not have the right cruising gear anymore, but the cassettes are easy enough to customize. Your RD might have a max cog of 28T, or not. "mid 90's" 105 is unfortunately not descriptive enough, but Shimano keeps ALL of their technical documents available online. See if you can find an EV of your RD to visually match, and go to the installation manual to get Max Cog and Max difference for it.

It is a RD-1055 — the old manual says max difference of 13, lower/upper limit of 12/28T.

zandoval 07-19-21 02:21 PM

I would go for a 7 speed cassette that has a 34T bail out gear. Of course that might need a long cage deraileur or a deraileur extension. Then if I still kept getting the Ummff I would change out the crank.

Iride01 07-19-21 02:24 PM

If you haven't already, you need to learn what the spec's of your DR's mean. Then you just need to learn what gear ratio might get you up that hill easily enough.

Then you'll have to play a game of what if I get this and what else will I be required to get because of my choice. When the what you need to get matches up with the dollar signs you are willing to spend, then you've found it.

You sure that isn't a freewheel on the back? A low gear of 28 on the back let me get up most hills around me okay on my Raleigh. But it also had a 53/39 on the front.

Being patient and just riding what you can ride for a year might give you the strength too and you won't have to spend your money. Or do you have plenty of riding experience behind you and it's the Kestrel you've only had for a month?

dsbrantjr 07-19-21 03:07 PM

https://www.kstoerz.com/gearcalc/compare/

san_antone_rose 07-19-21 03:26 PM


Originally Posted by Iride01 (Post 22148719)
If you haven't already, you need to learn what the spec's of your DR's mean. Then you just need to learn what gear ratio might get you up that hill easily enough.

Yes, beginning to grasp that I have more much understanding to develop! Y'all are very helpful though.

Then you'll have to play a game of what if I get this and what else will I be required to get because of my choice. When the what you need to get matches up with the dollar signs you are willing to spend, then you've found it.

This, it appears, is the name of the game.

You sure that isn't a freewheel on the back? A low gear of 28 on the back let me get up most hills around me okay on my Raleigh. But it also had a 53/39 on the front.

Definitely a cassette. I think that combo—upper end of 28, switching small chainring for a 39T—could work.

Being patient and just riding what you can ride for a year might give you the strength too and you won't have to spend your money. Or do you have plenty of riding experience behind you and it's the Kestrel you've only had for a month?

By no means am I in tip-top shape, but been riding for a while. It's the bike that's new, and I'm trying to do less dropping it at the shop and saying, "Alright, do what you need to."

Responses in bold above :)

ThermionicScott 07-19-21 03:39 PM

After only riding for a month, the absolute best way to improve your climbing is simply to keep riding and attacking those hills with gusto. But lower gearing will make that nicer to do in the meantime, so I'll play. ;)


Originally Posted by san_antone_rose (Post 22148683)
It is a RD-1055 — the old manual says max difference of 13, lower/upper limit of 12/28T.

The RD-1055 has a max chain wrap of 28 teeth, so of the suggestions tossed around, you can't do both a 50/34 crank and a 11-28 cassette (or a similar wide-range) without replacing the rear derailleur. Since the bike could probably do with a new cassette and chain anyway, that would be a logical and easy place to start. Shimano 12-28 cassettes are pretty cheap and plentiful.

A compact crank wouldn't hurt at some point, but you'll want to keep the whole system in mind for that. I used a 48/34 crank and 13-26 cassette together on my rando bike for a while, that worked really nicely within the RD's limits.

san_antone_rose 07-19-21 03:54 PM

Y'all rock -- I'm going to start with the cassette, see how that does me, and go from there. Is there any drastic difference in quality among the various 7 speed cassettes shimano (or SunRace) sells?

davidad 07-19-21 04:04 PM

This chart will give you some ideas about gearing. Bicycle Gear Inch & Shifting Pattern Calculator (jbarrm.com)
This crankset will give you low gearing for hills and still keep a fairly high gear if you can go that fast. NOS Vintage 1990s Suntour XC LTD Crankset | eBay

ThermionicScott 07-19-21 06:35 PM


Originally Posted by san_antone_rose (Post 22148849)
Y'all rock -- I'm going to start with the cassette, see how that does me, and go from there. Is there any drastic difference in quality among the various 7 speed cassettes shimano (or SunRace) sells?

AFAIK, the Japanese-made ones were all cold-forged steel, so should be equally durable. Only the surface treatment varied (chrome for the fanciest cassettes down to paint on the cheaper ones.)

Can't speak to what the cheaper ones use, but even if the durability is proportional to the price, I wouldn't be too disappointed. And they should all shift equally well -- I think Shimano tried to patent Hyperglide but couldn't, so everyone was able to copy it.

BTW, this is my favorite site for comparing gearing ideas: http://www.gear-calculator.com/

Unca_Sam 07-19-21 08:36 PM


Originally Posted by san_antone_rose (Post 22148683)
It is a RD-1055 — the old manual says max difference of 13, lower/upper limit of 12/28T.

Ok!
And a total capacity (difference between front chainrings plus difference between smallest and largest cog on cassette) of 28. You could choose any 12, 13, 14-28 7 speed cassette and put it on there without issue. Keep the "corncob" cassette for racing.

70sSanO 07-19-21 09:14 PM

Our son has an early 90’s Specialized Allez Epic with 7 speed 105. He doesn’t ride very much and we have hills.

What I would do is find a 39t inner chainring. It doesn’t have to be 7 speed, it just need to have a 130mm BCD.

It is almost impossible to find a a 13-32 cassette, I built one for our son, but you can get a 12-32 7 speed cassette. The gaps are pretty huge, but for now it will give you enough low end.

Get a long cage mtb rear derailleur compatible with a 7-9 Shimano SIS. This will let you run the 32t. I used an old Deore from the 80’s.

Once you ride enough with this setup, you’ll be able to make a decision on where you want to go. If your Kestrel has 126mm dropouts you are limited.

John

Russ Roth 07-19-21 10:36 PM

easiest and cheapest would be a 12-28 cassette, new chain to handle the different gearing in all likelihood and a 39t small ring. This would have been the max climbing gearing that system was designed to handle and isn't that horrible depending on your age and condition. As a 230-240lb 20 year old I would take 80 mile rides with that and climb 2 catskill mountains to visit the grandparents on longer college weekends and it wasn't that bad a climb. Currently my race bike still has that and I've slowed some, doubt I could do the same mountain climbs, but I still found it wasn't too high riding through the Finger Lakes last year. From there, just focus on riding more and climbing more, they'll do you fine in a lot of situations. I will grant that compact gearing can be nicer but a 39/28 isn't bad for a lot of hills.

hydrocarbon 07-20-21 12:46 AM


Originally Posted by Russ Roth (Post 22149335)
easiest and cheapest would be a 12-28 cassette, new chain to handle the different gearing in all likelihood and a 39t small ring. This would have been the max climbing gearing that system was designed to handle and isn't that horrible depending on your age and condition. As a 230-240lb 20 year old I would take 80 mile rides with that and climb 2 catskill mountains to visit the grandparents on longer college weekends and it wasn't that bad a climb. Currently my race bike still has that and I've slowed some, doubt I could do the same mountain climbs, but I still found it wasn't too high riding through the Finger Lakes last year. From there, just focus on riding more and climbing more, they'll do you fine in a lot of situations. I will grant that compact gearing can be nicer but a 39/28 isn't bad for a lot of hills.

For sure.

I like keeping things original when possible, plus the '90s Shimano 105 cranks are much better-looking on a bike from that period than the modern ones in my opinion. Changing the chain and cassette (and maybe getting a 39T small ring) is way more effective and cheaper than changing the entire crankset, which will still be undergeared for climbing on an 11-23T cassette.

At least start with the cassette since that needs regular replacement anyway; it's always possible switch to a compact crank later if the gearing isn't low enough.

canklecat 07-20-21 03:09 AM

A couple of my road bikes are still set up for 7-speed, one with a freewheel, the other with cassette.

The steel bike has a 50/38 chainring and 13-28 SunRace chromed MFM30 freewheel. It's darned near perfect, lacking only a big gear for downhills with a tailwind. In other words, it's not lacking anything important.

The carbon fiber bike came with an Ultegra 6700 crankset and 53/39 chainrings. Good enough, not cost effective to replace for minor differences. I'm currently borrowing a wheelset set up with a 7-speed cassette, the SunRace 11-28 cassette (CSM40, I think). I'd prefer the same cog setup as the 13-28 MFM30 freewheel. Stretching an 11 to 28 gap across only 7 cogs results in some awkward jumps that take me out of my rhythm. But the 39T chainring and 28T cog are fine for whatever climbs we have around here.

While I like the SunRace -- great values, no problems with quality in three years -- I don't care for the cog spacing in that particular 7-speed cassette with the 11-28 cogs.

So if you can find a 7-speed cassette in 13-28, try that. I had an older Shimano cassette in that range that felt about right, although it's worn out now. Unless I'm going downhill with a tailwind, I'll never spin out with a 53T big ring and 13T cog. I ain't that strong or fast. But the better spacing of the 13-28 across 7-speeds would be useful every ride.

If your crankset/chainring is 130 BCD, pretty standard back then, try a 38 or 39 small chainring. Vuelta sells some for a very reasonable price. I've used Vuelta SE Plus big rings and standard SE small rings in 39 and 38. They're as good as any of my older Suntour or Shimano chainrings.

I do have and occasionally need a smaller chainring and larger rear cog for climbing on my heavier hybrid. My old Univega hybrid has a 50/40/30 triple and 12-34 cassette, and sometimes I need that 30/34 combo on some short, steep climbs with that 30 lb bike, especially if I'm hauling stuff from errands. But I've never felt the need for that kind of gearing on my lighter road bikes. Subjectively, on a bike weighing 18-24 lbs, a 38 or 39 chainring and 28 cog feels about the same as the 30/34 combo on the heavier hybrid.

tkamd73 07-20-21 06:56 AM

RD-1055 works great with a 12-28 cassette and 42-53 chainrings. I’ve got 2 bikes with that set up.
Tim

grizzly59 07-20-21 08:09 AM

Search google "shimano rd-1055 pdf" for the docs on your RD. Look for the model # on your RD, change accordingly. PDF it will tell you how many teeth you can work with. You can bypass some headaches by switching to a long cage mountain RD. Long cage + 30 tooth rear cassette + compact crank = climbing machine. Compact crank may require a different FD, yours now is prob 14 tooth difference max. Search for a FD-xxxx, whatever your FD part# is. New crank may need a different BB as well.

Iride01 07-20-21 08:49 AM

I missed out on all the stuff between 7 speed freewheels and 11 speed cassettes. But just be wary that what you get is compatible with the freehub you have on your bike. I suppose you are back in the days where you can build your own stack so maybe you just need to replace a cog or two if you can find them.

If your DR can't handle the physical clearing of the bigger cogs you choose, then you can put a hangar extender on it. But that doesn't change any of the front difference or total capacity specs. Though you can always try and see if you can go a tooth or so more. Maybe maybe not. Bikes are different.

If you decide to spend money on a crank, I'd very much recommend you also consider a 2 piece crankset and BB that will move the BB bearings further outboard. Not so much that you'll notice the difference while on the bike, but you'll open up availability to more crankset choices whether you actually get one or not.

And rear DR's in the Shimano 105 line and below tend to be very inexpensive when new. Though depending on what you get you might have to change shifters, and that can be pricey.

J.Higgins 07-20-21 10:20 AM

Late to enter this thread, but I'll toss in my zwei pfennig.

I think that your Kestrel is geared a little too high for most people, and a toothier cassette would be worth the effort. Perhaps you have a bike co-op near you that would have a box full of cassettes to browse. That would be a low-cost method of finding out if a larger rear cogset is what you need.

It also seems to me like your Kestrel might be a worthy candidate for a new set of wheels, cranks, derailleurs, and shifters. If your bike fits you well and you like riding it, maybe a winter project this coming year? Might be worth it. Lots of money though. You could probably find a more-suitable bike on CL for the price of new components.

GhostRider62 07-20-21 10:28 AM

I have that exact bike hanging up somewhere. I have a 53/39 and 12-28 with Dura Ace. It ***** and wraps the chain just fine.

It should be easy to get a 39 small chainring and 12-28 cassette.

Badger6 07-20-21 11:46 AM


Originally Posted by san_antone_rose (Post 22148596)
I'm wondering what the best way to get some better climbing action is

Climb more. Honestly, that's it. Do intervals and repeats on hills.

But, gearing does matter, if your gearing is too tall, it'll make every climb miserable. And your gearing is pretty intense. Check out this gear calculator. Select gear inches or ratios to comparing the gears. Put in your current crank and cassette, then play with comparisons of different crank, different cassette, different crank and cassette. As others have said you will definitely benefit from a cassette with a larger low cog (the bigger one), and a compact crank would not be a bad idea either.


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