KCT1986

If you are planning to build the wheel on the FH-6600 @ 126mm and only plan on using it for a 7 speed cassette, you could do some of the OLD reduction on the DS. If you are willing to do the work and don't mind using parts from the FH-M650, you could swap in the thinner DS locknut from the M650 and also replace the DS spacer with a .5mm spacer. This will reduce the DS by aprox.1.7mm+/-.

Do the balance of the OLD reduction on the NDS. This will keep the tension balance almost the same as the 6600's original spec. A little lower, now @ aprox. 53% NDS/DS. 11 speeds hubs are usually in the 49% range. A little bit better than if you just do the adjustment on the NDS.

You may have to adjust the amount spacers you use behind the 7 speed cassette to get the right clearance and still be able to properly tension the cassette lockring.

Harold74

I meant for the "vetting" to be a conversion. A conversation in which I got to participate and voice my own opinions as well as receive the opinions of others.

I disagree. So far, they responded with opinions on relative wheel strength. Opinions that have not been established as fact. At the least, not within this thread. If you've got "proof" then, by all means, show your hand.

I disagree. I feel that I have gone to great lengths -- via rational argument and empirical measurement -- to establish what the facts may be. Just because I don't blindly accept your facts does not mean that I don't care about ascertaining the truth.

I disagree. I presented the lock nut to flange dimensions that Bill Kapaun specifically asked me for. And they demonstrated the same equivalency as the other measurement I presented. That, because they have all been mathematically related measurements targeted at establishing the same thing: the lateral, drive side spoke offset. Regardless, if you know of more relevant measurements, why not suggest them to me so that I can collect them for you? I can't read you mind from here.

1) The facts have not been established as facts thus far.

2) Multiple, sometimes contradictory opinions have been expressed in this thread. How am I to know which I should defer my own judgment to and accept as "facts"? Yours? Hondos? Who's?

3) How do I know that you, or anybody else here, knows what they are doing? How do you know that I don't know what I'm doing? It's the internet FFS. You're Elon Musk and I'm Beyonce... let's talk bikes.

4) Of course I'll build my wheel and see what happens. I don't need your permission for that.

Rather than denying my right to voice my opinions in my own thread, perhaps focus your efforts on proving these "facts" that you keep mentioning. That, or just move on.

I may well be wrong regarding wheel strength. If someone can prove that to be the case, I'll relish the opportunity to learn. Until then, I intend to remain a critical consumer of the information presented.

rccardr 

Have fun. I'm outie.

icemilkcoffee 

Since you have both hubs in front of you, can you get the center-line to left flange and center-line to right flange distance? Those are the important numbers because you want to know how far off center the hub is.
There is no question that an 11 sp hub has worse dishing than a 8-10 sp hub, and 8-10 sp hub worse dishing than a 7 sp on 126mm hub, which is in turn worse than the old 5 speed on 120mm hub. And the 5 speed hub is worse than the single speed hub, which has no dishing. The only question here is how much worse is it, compared to the 11 speed hub.

KCT1986

Here are the numbers that I posted a few months ago in Harold74's other post about hubs for building <11 speed. Excerpt has estimated NDS/DS tension for FHs 5700, 6600, 5800/R7000. Search that post for all details.

That discussion was on relative tension only, it did not touch on the lower bracing angle for 11 speed, which is inherent on 11 speed wheels on both sides.

My post from yesterday about the method to respace the FH-6600 shows comparison % based on Shimano's method measuring, (hub flange outside to outside).

Excerpt:

A comparison of Shimano 105 10sp FH-5700 and 11sp FH-5800/R7000
Based on Shimano's measurements, hub flange outside to outside, the NDS relative tensions are 10sp 55% 55.02%; 11sp 49% 48.95% (rounded). (not rounded)
Measured center of flange to center of flange, the NDS relative tensions are 10sp 53% 53.14%; 11sp 47% 46.87% (rounded). (not rounded)


Your FH-6600 should be about 54.17% outside to outside of flange, 52.3% center of flange to center of flange. The center of flange to center of flange number assumes a flange thickness of 3mm on each flange.
.
Regardless, the numbers to compare for structural comparison are 54.17% for FH-6600 vs. 48.95% for FH-R7000. So, there is about a 5% difference in tension balance between those hubs.

Harold74

Thanks for that. Even if I don't feel that I need to respace the DS for strength, it may be useful for chain line manipulation.

I do plan to run 7 speed but, as you can imagine, other options start to have appeal given that I'll be running an unmodified 10 speed hub. If I could reasonably get my hands on SL-7900...

Question: is the locknut to outer face of hub body dimension in any way standardized on stock bikes? Everything in my stable looks to be about the same but I would think that the desire to dial in the cassette chain line would necessitate monkeying with the DS spacing sometimes.

tFUnK

Given that I've never really had to fiddle with my high limit screw when I swap wheels, I wanna say you're right that they all look about the same (edit: within a speed eg, 10 speed to 10 speed wheelsets).

Hondo6

The definition of "vetting" is "make a careful and critical examination of (something)". It does not mean "have a conversation about".

You asked for "vetting". A critical examination of what you proposed to do is exactly what you got, along with some suggestions regarding how to proceed.

If you already have a fixed opinion and aren't willing to accept advice to the contrary, asking for advice and/or critical evaluation of what you plan to do is rather pointless.

Best of luck.

Harold74

And just how would one vet an idea in an internet forum without conversing about it? Telepathy?

You'll note that there's nothing in the definition of vetting that precludes the person doing the asking from participating in the vetting process.

I agree, the "vetting" has gone wonderfully for me in this thread and I'm grateful for the help. The only exception has been when I was, effectively, told to stop questioning the dogmatic wisdom of my "betters" which had not been proven in any physical sense. Wisdom which, it seems, was likely incorrect to begin with.

That's not what occurred here. My original plan, described in detail at the top, was to transplant a 7 speed freehub body onto a 10 speed hub. And I abandoned that plan as soon as KTC1986 demonstrated that it was unworkable. I have been -- and remain -- open to changing my opinions and plans in response to new evidence. However, for me to do that, there actually has to be new evidence.

Hondo6

Vetting of proposals/concepts/individuals routinely happens without significant 2-way communications. One example would be the rejection, without feedback, of a proposal submitted to a commercial firm or government agency because it was not selected for whatever reason (e.g., no need/not deemed feasible/funding lost/better proposal received). A second example would be a job application immediately "deep-sixed" without feedback because disqualifying derogatory information was found during the prospective employer's public records check concerning the applicant.

On an Internet forum, one can have something vetted without discussion by (a) submitting a proposal to a group of individuals more knowledgeable about the subject than oneself, then (b) considering criticism of the concept; discussion would only be necessary in order to to clarify information that wasn't clear in the initial proposal, or to ensure you understood the criticism and advice. And as you noted above you did both - the former by asking your concept to be vetted in your OP, and the latter by abandoning your original freehub transplant concept when told that was not workable.

However, IMO much of the rest of what you've said on this thread appears to me to little more than out-of-hand rejection of criticism/advice you don't like simply because you've made up your mind to "do things your way".

Your project, so your call; do whatever you want. Best of luck.

I'm done here.

Harold74

I disagree with that vehemently and, in fact, see it as almost the reverse. From my perspective, I am respectfully justifying my arguments with logic rooted in physics and it is others who are rejecting my arguments out of hand because I'm perceived as not being "expert" enough when it comes to wheel building.

When I've rejected the advice of others here it has not been because I don't like that advice but, rather, because I don't believe it. And that's not to say that the advice that I've rejected is necessarily incorrect. Much of the advice that I've rejected thus far has come from people unwilling to offer any convincing, physical proof to justify their recommendations. They've made little effort to be persuasive but instead, seem to be offended by any response from me other than unquestioning deference to their not so humble opinions.

I myself am a structural engineer by virtue of education and experience (~20 yr). If there's such a thing as a "Professional Strength Assessor", that's me. I get paid to figure out how strong or weak things are. That doesn't make me an expert on wheel building and it doesn't mean that I'm correct about any of the issues discussed here. What it does mean, in my opinion, is that it is entirely plausible that I might possess insights worthy of being shared here. But, then, I would argue that the same should be assumed of anyone participating in this thread regardless of their background.

Sure, it is possible to vet something without two way communication. But, then, what would be the benefit of doing that here? What is it that you would hope to gain by excluding me from this conversation that I initiated?

shelbyfv

I use the iggy list as a reminder so I'm not sucked in the next time.

Harold74

Definitely do that. While I appreciate help from anyone willing to offer it, I don't consider that help to be any kind of bargain when it comes with a requirement for unquestioning, irrational deference, which seems to be case with some folks. I'm interested in discussing interesting bike stuff with other, open minded bike nerds. The less that I have to contend with big, bruised egos in the future, the better. It's not as though there is a shortage of knowledgeable, congenial bike nerds here.

Harold74

I'm probably just talking to myself at this point but, regardless, I'm going to critically evaluate those statements which, unless I'm mistaken, validate my my supposition that FH-6600 + 126 OLN will be stronger than FH-R7000 + 130 OLN. If you disagree with anything that follows, I'd love to hear about it.

1) the principal reason that we concern ourselves with relative spoke tension is to prevent the NDS spokes from relaxing to the point of losing their prestress under service riding conditions (vertical, lateral, torsional wheel loads). When spokes de-tension, that's when the scary stuff happens.

2) Per your numbers, the 6600 option has a 10.7% greater margin against spoke de-tensioning (100 x (54 - 49 ) / 49). In this sense, The 6660 option is 10.7% stronger than is the R7000 option.

3) Bracing angle is about the lateral stiffness of the wheel and is affected by both the NDS and DS spokes, so long as those spokes remain in tension as they should. As such, relative wheel stiffness is pretty much just a function of flange spacing. Since the flange spacing on the 6600 is a bit wider than it is on the R7000, the 6600 comes out the winner again, albeit by a margin that I do not consider significant in light of wheel building tolerances.

4) Thus far, I've been contemplating wheels that have the same number of spokes. Matters improve when one considers that I'll be 170 lbs on 32H 10sp when there are plenty of people cruising around 220 lbs on 24H 11sp. In rough terms, this can be expected to yield another 33% margin (32/24) on ensuring spoke pretension.

All tolled -- and including the 32H / 24H business -- the 10sp FH-6600 + 126 OLN will come out almost 50% stronger than the 11sp FH-R7000 + 130 OLN being ridden successfully by people 30% heavier than me.

KCT1986

Been having internet problems this week, so a delayed response.

1. The relative spoke tension is a factor in determining what L/R tension you want to shoot for. If the rim is rated for 110 Kgf then a hub with a L/R under 50% would put the left at about 55 Kgf or lower. Depending on the rider/use of the wheel this may cause an issue with loosening of nipples or repetitive stress failure of the spoke. Less rigid rims will benefit from higher L/R balance & other build factors that reduce stress (# of spokes, butt spokes, crossing pattern,,,).

2. Yes, these are the estimated L/R tension #s based on Shimano's specs.

3. Yes, the bracing angle affects lateral stability and durability from any side impact.

4. Another factor is that these low spoke count wheels often have more rigid rims (carbon, deep profiles, wider ID...) that are capable of much higher tensions. Hubs on these wheels often use straight pull spokes that eliminate.the 'J' bend that weaken spokes.

Regarding you other inquiry of standardized spacing of hub positioning, this seems to be most common.


Shimano & SRAM seems to commonly use this spec for 8/9/10 speed. Add 1.85mm +/- for 11 speed.
Depending on frame dropout configuration and cassette, you can go a little lower. For the best achievable L/R tension balance, especially for 126mm spaced frames, you want to configure the cones/spacers on the right side to have the smallest clearance, (right side hub flange as far outside as possible). If you cross chain Small/Small, adjust accordingly.

Harold74

Thanks for that. Given that nipple loosening and fatigue are both downstream consequences of a loss of spoke prestress, it sounds as though we're in substantial agreement.

Just what I was looking for. I'd love the same for speeds 5 - 7 but I imagine that things were probably less standardized "back in the day".

Do you know if 126 OLN bikes typically had the same 43.5 mm chain line that is common on 130 ON bikes in recent times? I get the impression that it might have been a bit less but I don't have enough data points to know if any confidence.

Harold74

I've discovered that what I am contemplating has been done before by community member miamijim. I'm going to attempt to summon him to this thread to comment on the degree of long term success that he has had on his project as well other input that he may have on my project.

10-speeds on a 126mm hub SUCCESS

I've become quite excited about building up a set of 10 speed / 126 OLN wheels. I maintain a couple of vintage road bikes in the stable at any given time with frames rotating in and out frequently as interesting opportunities arise. While I like working on wheels, I often find that sorting them out for each new project really slows down how quickly I can get from frame acquisition to finished project on any particular bike. In the future, I plan to limit myself to frames with 700c wheels and 126 OLN such that I can just keep reusing this one, awesome set of wheels that will satisfy the following "wants":

1) 7 speed freehub rather than freewheel.
2) Mechanically sound wheel build that can be easily trued.
3) Quality hub that has been rebuilt and can continue to be.
4) Quality rim that can run tires from 23 mm to 28 mm.
5) Desired aesthetic. I might build one set in silver and one in black.
6) Future proofed cassette options in case quality, 7 speed cassettes in gear ranges that I like become difficult to source.

As can be imagined, I never inherit a set of wheels that captures all of that goodness.

As an example, I currently want to do 9 of 10 on a Zullo frame that I picked up last month and still be able to use the original Campagnolo Nuovo Record RD which tops out at 25T +/-. In theory, I might just be able to:

A) install a 9 speed cassette without omitting any cogs (no weird gear steps).
B) lock the rear derailleur out at the 2nd to lowest cog, having picked a cassette where that's 25T or less.
C) friction shift up a storm on that sexy Nuovo Record RD.

To me, this feels like a whole lot of upside with no meaningful downside.

icemilkcoffee 

no you can’t. The 10 speed cassette is a special case. The back side is dished in 1mm - in fact it is shipped with a 1mm spacer to go behind the cassette. You cannot fit the whole 9 speed cassette in that 7 speed freehub.

KCT1986

Glad that you are seeing that the relationship between NDS/DS spoke tension % and its part in the wheel strengthen is real (and an 8-10% difference is substantial and not 'margin of error').

Don't know if there was a common measurement for 5 -7 speed, but for those wheels the dishing was not so extreme, and since freewheels were common, difference easily existed. Friction shifting was also standard for many of those years so it was not as much of a factor. It was only when index shifting came around that we became concerned about sprocket positioning in relation.to dropout.



The 40.75mm # is commonly used as standard spec, but when trying to go below 130mm OLD going a little lower is beneficial if possible. You should re-read my post #26 above and absorb it fully.

Harold74

I'm confused. In the permutation that I'm proposing, there is no 7 speed hub. Rather, it's an 8/9/10 hub laced into a 126 OLN wheel. In that sense, it's fitting a 9 speed cassette on a 9 speed freehub. What am I missing?

KCT1986

The old post of '10 speed on 126' is very good. Too bad that pics are no longer included for the original post. Hopefully he will see the interest in that thread and reload the pictures for anyone who happens upon that thread.

A long term review of how it all worked out would also be good since the resulting dish was somewhat extreme, probably in the 43-44% NDS/DS range.

Harold74

Agreed. Something that caught my eye in that thread was that someone suggested that, perhaps, it only worked out because miamijim's 10 speed hub -- which I believe was similar but not identical to mine -- had uncommonly good dish to begin with. I'm not sure if that hypothesis was confirmed but, were that to be the case, then it would be something that anyone attempting a similar wheel build would want to consider. It would also inspire me to go on Ebay and find a t least one more pair of these, potentially "special", hubs.

Harold74

I never doubted that the relationship between NDS/DS spoke tensions played a part in wheel strength. What I doubted was that my proposed [10 speed hub + 126 OLN] build would be appreciably weaker than a ubiquitous [11 speed hub + 130 OLN] build. And, thus far, that hypothesis seems to have withstood all challenges. By the numbers (yours and mine), my 126 OLN franken-wheel build would actually be the stronger of the two builds.

What makes you feel that I have not absorbed it fully? I understand that I could perform a little spacer voodoo to improve the dish on my [10 speed hub + 126 OLN] build. That said, I see no reason to do that unless I were dissatisfied with a level of wheel strength commensurate with a [11 speed hub + 130 OLN] build. And I'm fine with that level of wheel strength.

Harold74

From a basic engineering standpoint, much of this discussion amounts to assessing:

1) Provided wheel strength relative to;
2) Required wheel strength.

It's fairly straightforward to assess the provided wheel strength, at least in relative terms (what is better or worse).

For me at least, the difficulty comes in assessing the required wheel strength. How strong should a wheel be vertically, laterally, and torsionally? I truly don't know the answer which is why I've been basing what is acceptable upon the expected strength of other wheels that are ubiquitous and successful in the wild (11 speed 130 OLN for example).

Does anyone know of a wheel testing standard / protocol? I would think that, when someone (Bontrager for example) develops a new wheel, it would have to undergo some manner of testing prior to being introduced to market.

Harold74

I think that I understand the source of confusion here:

That should really be just have been "1) freehub rather than freewheel". In this instance it would be a 10 speed freehub that will probably start off with a 7 speed cassette and spacer and, possibly, migrate to a 9 or 10 speed cassette w/o spacer in the future.