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Super Record chain wrap

Old 07-09-20, 11:46 AM
  #26  
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Originally Posted by Piff
edit: Ah, I just read more closely and saw your big and small rings are 49/32. That's less range than what I was attempting. Still. I'd just use a mid or long cage.
Honestly, my bike collection looks like it was curated to show all the different ways to set up a triple. Most of them do have a longer cage. Now, I'm exploring the edges of what else is possible. This is one of my favorites -- SunTour Superbe with a Red Clover triplizer and a 3 pulley cage. This one, I'll admit, I did just because I could.

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Old 07-09-20, 11:55 AM
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I'd rank the offenses to tradition that I have inflicted on this bike like this:
Not that you asked, but here's my take on your list.


1. Clipless pedals. --- Temporary pass for adding miles.
2. Modern compact handlebars --- They ain't aerobars...
3. Non-coil cable housing at the rear derailleur Bitd common, what one had.
4. Absurdly long valve stems. --- Definitely detracts, visually, but if that's the tube you got, that's the tube you ride.
5. Tall stem. --- Level seat and bars was common, except for actual (or pretend) racers.
6. Triplized crankset --- Umm, Tulio may have created (sanctioned) the little ring and axle, but did Aldo? But as a mere mortal you get a pass, this time.
7. Modern clincher rims, polished silver not dark anodized. --- polished aluminum was always part of the mix, from before the dark anodizing. Clincher? I'm not so sure about. I have some myself...
8. Brake cables too long --- Yeah, THIS.
9. Not period correct bottle cage. --- Earlier isn't it? That's ok.
10. Quick link in the chain. --- Don't ask, don't tell. In this particular case, I think it's ok.

NR rings with inner ring still present? Seriously??? Definitely not raced that way.
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Last edited by Last ride 76; 07-09-20 at 12:00 PM.
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Old 07-09-20, 12:21 PM
  #28  
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Originally Posted by Last ride 76
9. Not period correct bottle cage. --- Earlier isn't it? That's ok.
I could be wrong about the bottle cage. It's branded by Specialized. It could be from the 80's I guess. I was picturing this as the correct cage.


(Photo from VeloBase.)

I don't know why I keep having this problem with my brake cables. I set them up in the garage and they look OK to me, then I take a picture and it looks like I'm trying to lasso somebody.
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Old 07-09-20, 12:46 PM
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Your low gear from the 32/24 combo is 35 gear inches. A 42/28 combo from a double would have given 39 inches, not too far off.
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Old 07-09-20, 12:49 PM
  #30  
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For extending a rear derailleur capacity a Wolf Tooth Roadlink is excellent. It lets you use the same derailleur most times.


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Old 07-09-20, 01:08 PM
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Originally Posted by SurferRosa
Your low gear from the 32/24 combo is 35 gear inches. A 42/28 combo from a double would have given 39 inches, not too far off.
Yeah, I spent a couple of hours playing with gear-calculator,com comparing different combinations. 42-28 is what I was using in my previous build. The new configuration extends that a bit (12% lower) and adds an extra option or two in the speed range where I do most of my riding. The whole project is an obvious rebellion against rule 5, but that's the way I roll.
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Old 07-09-20, 01:14 PM
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Originally Posted by Miele Man
For extending a rear derailleur capacity a Wolf Tooth Roadlink is excellent. It lets you use the same derailleur most times.
Does that increase the wrap capacity or just the largest cog that will work?

I've got one of those on my 2013 Kona Jake the Snake, where I'm using a 12-36 cassette with a 46-34 crankset and a Gevenalle BURD rear derailleur.
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Old 07-09-20, 01:21 PM
  #33  
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Originally Posted by SurferRosa
Your low gear from the 32/24 combo is 35 gear inches. A 42/28 combo from a double would have given 39 inches, not too far off.
My first post here so I hope I am not stepping on anyone's toes. I agree that OP is going to a lot of expense and trouble to get a gear that is only 10% lower than what is pretty commonly done (42/28) by others. But staying with what the OP is wanting to do, if it were me I would add another link of chain. With that much tension on the chain in the larger rear sprockets, I think you may find that the derailleur is hesitant to upshift out of those gears. At least that was my experience running a short chain like that on a NR derailleur. By the time you've moved the derailleur enough to get off of the larger cog you end up two cogs away, not at the adjacent sprocket.

The additional link will mean that the chain will hang slack in the small/small combos but, if I understood you in the first place, the purpose of the triple is to get some "bail-out gears" for steeper hills and you won't need to use the ratios that the small/small combinations provide.
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Old 07-09-20, 02:12 PM
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Originally Posted by daka
My first post here so I hope I am not stepping on anyone's toes. I agree that OP is going to a lot of expense and trouble to get a gear that is only 10% lower than what is pretty commonly done (42/28) by others. But staying with what the OP is wanting to do, if it were me I would add another link of chain. With that much tension on the chain in the larger rear sprockets, I think you may find that the derailleur is hesitant to upshift out of those gears. At least that was my experience running a short chain like that on a NR derailleur. By the time you've moved the derailleur enough to get off of the larger cog you end up two cogs away, not at the adjacent sprocket.

The additional link will mean that the chain will hang slack in the small/small combos but, if I understood you in the first place, the purpose of the triple is to get some "bail-out gears" for steeper hills and you won't need to use the ratios that the small/small combinations provide.
That's fair. I had all of these components on hand, so the only real expense is that they came out of my parts bin. I really wanted to make the 26T freewheel work, which would have given me an almost 22% lower gear, but I just wasn't happy with the number of slack gears I'd end up with using the 12-26 freewheel I had on the shelf. I might try it later with a 14-26. Frankly, I'm a little surprised that the C&V purists don't think a freewheel with a 28T cog looks worse than the way I have this set up with a triple. I know at least one member of this forum who wouldn't even like my 13-24 freewheel with a double because it doesn't have the classic corncob look. He's a much stronger rider than I am.

I'll see how well this works when I put it on the road, but in the stand it feels like all of the gears are basically acceptable.
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Old 07-09-20, 02:46 PM
  #35  
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Pretty much anything you do to obtain lower gears will violate the racebike aesthetic, but you won't get criticism from me. It would take eternal youth and a full-time program to maintain a level of fitness to push "good looking" gears over hilly terrain. Not to mention that if the aesthetics police get into my garage, I've got a much bigger problems than you do.
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Old 07-09-20, 05:28 PM
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@daka I agree. Even as a non-vintage aged C&V member, "good looking" gears in, say, Seattle proper are for preening and peacocking. I love the look, but 10-15% grades make a mockery of them, err...me. Best for flat courses and failing to impress the single, and fairer sex. Ask me how I know.

Andy, I think the chain length/wrap is fine so long as the big-big combo is avoided, like it is mostly for us cyclists. Having the extra grace built into the system for brain fart moments is nice, though, I will admit.

A critical questions, perhaps, is this: once mentally signed up for a triple, do you tend to get...opportunistic as to how low a gear you can fit? Sure, pushing a 12-23/12-25 FW or cassette with a 42/52 or 39/53 chainring combo can be tough at times, but do you find yourself content with leaving the 23T or 25T low cog in the rear with the additional 28-36T low ring in front? Or do you find yourself wanting to go for maximum potential and trying to fit a 28-32T max cog in the back? I know we're talking about a 28T presently, but this goes for other builds. I will admit to chasing the 1:1 or better low-combo, even if the reality of a 12-23 or 12-25 rear gearset is ideal for cadence-to-effort fine-tuning. Something that Campagnolo, with their 13-26T 9- and 10-speed cassettes, are really good at. I remember one Port Angeles ride (60 miles total, out to The Hook) with the Miyata 1000 where I really enjoyed being a human CVT with that rear gearset.
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Old 07-09-20, 05:52 PM
  #37  
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Originally Posted by daka
a lot of expense and trouble to get a gear that is only 10% lower than what is pretty commonly done (42/28) by others.
Well, I can tell ya, ten percent feels like a lot if you're really used to a 42t small ring and suddenly change to 39t. I mentioned this to @Wildwood a while back: it's like you're getting electric assist on the big climbs you frequent, those your memory has learned as a certain kind of pain. He said, "does anyone ever call you on your s***?"



So, Andy would have to use a more compact double to realize the same low gear he's getting ... or use a long cage rd, etc. etc.

I just wish this were that easy for me. But that damn 144bcd on every bike...

@Lascauxcaveman, can I get up Hurricane Ridge on a 42/28t low gear using Nuovo Record? What if I switch to a Suntour GT rd and 42/32t? Amphetamines help?

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Old 07-09-20, 06:19 PM
  #38  
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Originally Posted by RiddleOfSteel
@daka I agree. Even as a non-vintage aged C&V member, "good looking" gears in, say, Seattle proper are for preening and peacocking. I love the look, but 10-15% grades make a mockery of them, err...me. Best for flat courses and failing to impress the single, and fairer sex. Ask me how I know.
It's why you never want to ride your beater commuter with a wide-range freewheel to a singles bar. For the ladies it's all about what gear you're packing, and it better be small.
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Old 07-09-20, 06:54 PM
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Originally Posted by Piff
It's why you never want to ride your beater commuter with a wide-range freewheel to a singles bar. For the ladies it's all about what gear you're packing, and it better be small.
I figure a wide-range FW or cassette is the bike equivalent of compensating...so yeah, compact-range means one is a real Hardman...
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Old 07-09-20, 06:59 PM
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Originally Posted by SurferRosa
@Lascauxcaveman, can I get up Hurricane Ridge on a 42/28t low gear using Nuovo Record? What if I switch to a Suntour GT rd and 42/32t? Amphetamines help?
A few years ago, I did Hurricane Ridge with Mr. Caveman and some other BF members. 39-28T was my low combo and I was in it for almost all of it. If you're pretty good at being a steady gorilla with slightly higher gearing on 5-5.5% grades, then you can hang on for 17+ miles. Otherwise a 50/34 compact will make it a bit easier. Maybe I'd want to do it with that combo again, or maybe not. I will say that having a 53-11T high combo for the run down was/is a superb choice. I even spun it out past 120 RPM! Fair curves that are plenty easy to never have to brake, and I'm no daredevil. I've been meaning to do the ridge again, and that's a possibility now that my left knee isn't in mutiny mode. Saddle height isn't fully set, but we're getting there.
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Old 07-09-20, 07:44 PM
  #41  
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That setup worries me to look at. I was racing and working in bike shops when the Super Record parts first showed up, so I'm very familiar with the limitations of that derailleur.

It's not a Suntour or other slant-parallelogram design. Please forget about the modern mania for making sure that all possible gear combinations are available. With your setup, they can't be. No kidding. Here's why:

The Super Record is just a refined version of the earlier Campagnolo designs, e.g., the Sportsman. Look in the racer's bible from the 1950s and 1960s, the so-called "Cinelli book," to see how such derailleurs were originally intended to be used. My copy includes an illustration of the correct shifting method: there's a four-sprocket straight block with two chainrings, where dotted lines indicate that the inner two sprockets are to be used with the inner (47-tooth) chainring and the outer two with the outer (50-tooth) chainring. Two chainrings, four sprockets, close ratios, four allowable combinations.

If I were to try using a triple crankset with your derailleur and freewheel, I'd train myself to use the inner three sprockets with the small ring, the middle three (including the third largest sprocket, if that's one of the middle three) with the middle chainring, and the outer three (again including the next largest sprocket if appropriate) with the big ring.

I'd also cut the chain such that it sagged in some of the gear combinations that you want to try to salvage, because riding with a sagging chain might be unsightly, but it won't wreck your derailleur. Or the dropout. Or the spokes, should the derailleur do a kamikaze dive into the wheel. That painfully stretched derailleur may work fine on the work stand, but on the road, under load . . . . .

Last edited by Trakhak; 07-09-20 at 07:49 PM.
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Old 07-09-20, 07:49 PM
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Originally Posted by RiddleOfSteel
A critical questions, perhaps, is this: once mentally signed up for a triple, do you tend to get...opportunistic as to how low a gear you can fit? Sure, pushing a 12-23/12-25 FW or cassette with a 42/52 or 39/53 chainring combo can be tough at times, but do you find yourself content with leaving the 23T or 25T low cog in the rear with the additional 28-36T low ring in front? Or do you find yourself wanting to go for maximum potential and trying to fit a 28-32T max cog in the back? I know we're talking about a 28T presently, but this goes for other builds. I will admit to chasing the 1:1 or better low-combo, even if the reality of a 12-23 or 12-25 rear gearset is ideal for cadence-to-effort fine-tuning. Something that Campagnolo, with their 13-26T 9- and 10-speed cassettes, are really good at. I remember one Port Angeles ride (60 miles total, out to The Hook) with the Miyata 1000 where I really enjoyed being a human CVT with that rear gearset.
Generally, I like to have a 30 inch gear for hilly rides and I've been known to go as low as 24 inch (which led to aggiegrads making the classic remark that his 24 inch gear is two feet). The hill up to my house is 1/4 mile maxing out at 20% grade. Anything less than 30 inches and I am using the "two feet" gear. Fortunately, most of the hills around here are in the 3-7% range.
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Old 07-09-20, 07:54 PM
  #43  
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Originally Posted by SurferRosa
@Lascauxcaveman, can I get up Hurricane Ridge on a 42/28t low gear using Nuovo Record? What if I switch to a Suntour GT rd and 42/32t? Amphetamines help?
The one time I followed the Caveman up Hurricane Ridge (on the ride the RiddleOfSteel mentioned) I used a 50-39-30 and 13-29 and spent most of the time wishing I had a lower gear. But I've got a triple on almost every bike, so I'm soft.
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Old 07-09-20, 08:07 PM
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Originally Posted by Trakhak
If I were to try using a triple crankset with your derailleur and freewheel, I'd train myself to use the inner three sprockets with the small ring, the middle three (including the third largest sprocket, if that's one of the middle three) with the middle chainring, and the outer three (again including the next largest sprocket if appropriate) with the big ring.
I have triples on most of my bikes and I do the vast majority of my riding with the middle ring. I generally don't shift to the big ring unless I'm about to spin out the middle ring (which typically means I'm going down hill, because 42-13 will get me 25 mph), and I only shift to the small ring when I'm about to hit a steep climb. Besides, downtube shifters give me a tactile/visual reminder of when I'm hitting the extremes. I feel OK with this the way it is now.
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Old 07-09-20, 10:38 PM
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Originally Posted by RiddleOfSteel
I've been meaning to do the ridge again, and that's a possibility now that my left knee isn't in mutiny mode. Saddle height isn't fully set, but we're getting there.
Good to hear.
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Old 07-09-20, 10:44 PM
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Originally Posted by Trakhak
forget the modern mania for making sure that all possible gear combinations are available.
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Old 07-10-20, 12:45 AM
  #47  
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Originally Posted by SurferRosa
@Lascauxcaveman, can I get up Hurricane Ridge on a 42/28t low gear using Nuovo Record? What if I switch to a Suntour GT rd and 42/32t? Amphetamines help?
Ask @Drillium Dude about that. Definitely bring the amphetamines, if you're going for the 42/28 bailout combo. Or train hard with @northbend for a month or two. Or both.

I'm with @Andy_K and insist on having a triple for that kind of sustained climbing. I mean, you're talking seventeen straight miles of unrelenting hill. 30 gear inches or less, and I'm going to survive ir, maybe.

BTW, if you're thinking of coming over, let me know. I'd like to do that ride again and it's been awhile. You too, @RiddleOfSteel.
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Old 07-17-20, 01:21 AM
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Following up on this for the morbidly curious....

As seen previously in this thread, I finished putting the bike together with the 49-42-32 crank and the 13-24 casseete last week. On Saturday, I took it out for a test ride. Ironically, the route I was riding was extremely flat. It did have a couple of rolling hills though. RideWithGPS claims one pitch got as steep as 5%. Very short, maybe 100 feet of elevation gain, but enough to feel what the gearing is like. Conclusion: I love it! Really comfortable gearing. Shifting was great. All good.

But I do have a minor glitch in my build to report. Before I took it out, I noticed there was a spot where I felt a bit of drag when rotating the pedals. Not much, just a a little more drag than the rest of the rotation. I had the chain on the middle ring, so it definitely wasn't a chain length issue, so I ignored it. During the ride, I didn't notice at all. Everything felt extremely smooth and efficient. But when I got home I put the bike in the stand to wipe it down, and I felt it again. This time I looked closer to see what was going on. It turned out the inner chainring was very slightly rubbing the chainstay in one spot. Through the rest of the rotation, the small ring was clearing the chainstay by just a hair's width. Oops.

First, let me say I'm very happy to report that even after a 33 mile ride on this, it didn't even scrape this paint down to the primer. That's nothing short of a Festivus miracle, IMO.

I didn't even think this through. I've got another bike with a triplized Campy Strada crankset, so I just used the same bottom bracket length on this one that I had on the first -- UN55 70x122.5. That's the longest Italian threaded square taper I could find, and I didn't even question it. Those of you with deep knowledge of Campy bottom bracket spindle lengths can probably guess what happened here. The crank I triplized before was pre-CPSC, but the one on the Gios was post-CPSC. The post-CPSC crank is designed for a longer spindle -- 115.5 mm asymmetric spindle, offset ~3 mm to the drive side, so I figure equivalent to a 118.5 symmetric spindle; Going to a triple, I want to push the chainline out about 4mm, doubled for the symmetric bottom bracket, so I need about a 126.5 bottom bracket??? I am using a Campy crank on an ISO spindle, so theoretically I should get an extra few mm from that, but I have no idea how many time this crank has been on an off a spindle. tl;dr -- I'm not surprised I had problems.

Solution? There's a guy on eBay (mtbtools) who sells spacers for Italian bottom brackets for a couple of bucks. I knew this because when I built my De Rosa, I discovered that someone had shaved the bottom bracket down to 68mm, so I had to buy a spacer then. I bought another 2mm spacer, put it behind the bottom bracket on the drive side, and Bob's my uncle. I now have daylight between the chainring and the chainstay all the way around.

As Sallah said to Indiana Jones, "I told you it would be alright!"
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