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3Rensho Super Record Export Aero (SRA)

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3Rensho Super Record Export Aero (SRA)

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Old 07-10-18, 05:56 PM
  #26  
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You are going to like those Roval wheels. Perfect choice. They ride great.
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Old 07-12-18, 08:45 AM
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Nice to see you’re getting going on the 3Rensho! Been waiting for this one.

Im going a different route on mine. Was doing a Super Record build but have other plans now.

Keep up the great work!
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Old 07-12-18, 08:56 AM
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Very neat detail on the brake lever modifications, it’ll be interesting seeing those come together. Slick wheels as well. Looking forward to more as projects move through the pipeline. Enjoy!

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Old 07-12-18, 09:28 AM
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Great unique choice for the wheels and hubs. Look forward to seeing it come together.
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Old 08-14-18, 12:28 PM
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Aero conversion part 1 (of 5)

This is going to be quite long. If under 30 - please think of it as a lot of text messages in a row… or just look at the pictures. ;-)

I wrote earlier:
“Considering the frame being from 1983 and Campagnolo not yet fully into aero routing of the brake cables I am going to replicate aero routing a la pre C-record era. Which means modifying Record/Super Record brake handles for aero routing.”

So… as per my last post Campagnolo obviously facilitated aero routing by changing the cast/mold of the brake handle body in the end of the NR/SR era.



They made it possible for anyone to modify the brake handles for aero routing. In my opinion that also shows what path Campagnolo thought to be logic and mechanically sound for road bars and it became their solution for aero routing with the next generation - C-record.

There are other ways of getting aero routing using R/SR handles but in my opinion they are intended for time trial and bullhorn bars because of their cable routing. I will walk you thru these alternatives along the way.

Converting R/SR brake handles to aero routing has a bad reputation. Bad braking due to lack of leverage, a lot of friction caused by bends to the cable and cable housing, etc. I believe this reputation is mostly caused by a misunderstanding of what aero conversion method that suites your intended purpose. I hope to put some light on what I believe may have caused the bad reputation.

Here they are – what I call - the time trial and bullhorn solutions:

The quick and easy TT:
Cable with its cable anchor routed from the top (which has to be drilled a tiny bit to get the anchor to seat properly) and the cable housing directly attached to what used to be the original cable anchor seat (which has to be turned around to get the slot facing forwards). This method means cable housing must be free to move some - which makes a close to the brake handle body entrance for thru the bars routing difficult. Further away from the body would work or just tucked under the bar wrap as long as there is a portion of the cable housing being free to move and you can get a good hand position while riding.
Plus side + :
The same leverage as the original non aero routing. No sharp bends on cable housing.
Minus side - :
Cable housing still in the wind or at least a portion of it. Exposed cable housing might limit hand positioning.

I did not want to drill the body for the anchor – cable anchor not seated properly in pic.



Slot facing forward after flipping.



Working great.





On (fake) bullhorn bar.



The same solution on a road bar will result in a lot of exposed cable housing or if trying to get it inside the bar or under the bar tape it will result in extreme bends = bad reputation.



The developed TT:
Cable with its cable anchor routed from the top and the cable housing attached to the brakehandle body at a drilled hole thru the lower portion of the body. To get brake leverage there is a pulley/roller attached to a bushing of some sort - where the non aero original cable anchor seat used to be.
Plus side + :
No exposed cable housing at the brake handles.
Minus side - :
Leverage is weaker than original due to the geometry between cable anchor, pulley and cable housing stop. More bend on cable housing compared to “quick and easy TT” above.

This method do give some cable and housing bend when entering the handlebar and has less leverage but as bullhorns are mostly used on time trial bikes the braking is probably sufficient (obviously as it has been used by pro TT racers).

If used on road bars there will be a short and sharp bend. And very probably not sufficient braking in a road race situation = bad reputation again.

I apologize in beforehand for using the first picture that I have found on the net and I do not know any longer who’s it is. Let me know if you do. The two latter I found on steel-vintage.com






Last edited by styggno1; 08-14-18 at 01:09 PM.
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Old 08-14-18, 12:39 PM
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Part 2 (of 5)

So - for road bars the aero conversion has to be a bit different and this is what Campagnolo themselves went for:

A small pin attached to the brakehandle. Some kind of roller or pulley on the pin. A drilled hole in the brake handle body upper part and an exterior and larger drilled seating for the cable housing ferrule. If the pin and roller/pulley is placed as far up and to the front of the handle as possible there is ample leverage. Giving almost identical leverage and the same routing as the next generation of levers. No sharp bends to the cables or housing. Well - there is a tight radius bend to the cable above the cable anchor, at the roller, but it does not go inside the cable housing which means it does not add to friction.

As seen in the pictures below – provided by my Swedish vintage bike friend Michele Francesconi (OK - he is half Italian). He has them on a beautiful Colnago. This modification was done by Campagnolo and the brake handles were provided to some pro teams (there goes my earlier “not getting into the debate”). The drilling for the seating of the cable housing has the same finish as the rest of the body – hence - done by Campagnolo or a close affiliate. I would say it is certain. So does Michele who competed at the time and has been into bike racing and bikes during and since these were made. According to Michele the Renault Elf team and La Vie Claire used them. Pictures of Fignon at Renault Elf and Hinault at La Vie Claire using them is easy to find on the net. There is no doubt – Campagnolo.







Next I will show some further examples of what I mean by misunderstanding/wrong use of aero conversion.

I have already mentioned the TT/bullhorn routing being used on road bars giving bad results. The other way around can be as bad.

Pic stolen at speedbicycles.ch on the net – with my graphic comment.





And mixing them. These pics are Ray Dobbins without his permission and I have added graphic comments. Road bar with the correct lever but routing done TT/bullhorn direction downwards. I do not know if Ray just had the levers and not the correct body to go with them or if there was another reason. The sharp bend on the cable housing inside the bar goes without saying. The cable end anchor is on top of body, the cable goes in front of the roller – and then to a hole in the body’s lower section. The original cable anchor seat bushing is still there. I would have thought the bushing would obstruct the cable path but I am likely wrong. He writes that it works nicely so I must be wrong (about that part – not the housing bend part).




I believe the bad reputation of aero conversions to a large extent stems from choosing the wrong solution for the intended use rather than the conversions themselves. Add to that bad executions and set up errors.

Can a properly chosen, executed and set up aero conversion be as good as the non aero original? Probably not. The brake handles are after all not designed for this. It is an afterthought. Can they be good enough? Campagnolo certainly thought so. They would not have equipped professionals with their aero conversions otherwise. A year later or so C-Record was released.

Here is Hinault and Moser at Trofeo Baracchi 1984. A very pedagogical picture - showing aero TT and aero road conversions. Observe the extra bulge on top of Hinault´s brake handles and the lack of on top of Moser´s.



Fignon at a road race




This is what I want for my 3Rensho Super Record Aero. I want aero brake cable routing! I do not only want it – I need it for this project. It is the whole point. As these brakehandles are as rare as hen’s teeth - being pro equipment – I have unsuccessfully been on the prowl for a set for quite some time. Waiting for a pair to surface on the market are likely to put me and the 3Rensho SR Aero in limbo – possibly forever…!

In the end I realized I had to make them myself.

I have a set of NOS but shopworn Super Record brake handles and a lot of Campagnolo spare parts. I have tools and know how to use them. Sometimes I have a bit of imagination. How difficult can it be!? Can I even improve on the design?

Intermission (this post is long). I will be back with part 3.

Last edited by styggno1; 08-14-18 at 01:21 PM.
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Old 08-14-18, 12:49 PM
  #32  
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Part 3 (of 5)

I like to put up limitations for myself in my projects. Some kind of rules. I like to plan and to dwell on things. The journey is the goal. I believe it is more fun that way. It can be anything. “I have to use only X” or “It has to be made in X” or “I must have or make the parts – no buying this time”, “only tinker with bikes when sober” ;-) etc, etc. No matter what hobby I am into for the moment - I do it to challenge and hopefully also expand my comfort zone.

For this pre C-record era SR aero routing project I put up these rules:
I have to use only Campagnolo parts to modify the brake handles. Parts must be period correct. Forget the team brake handles. Forget what actually happened back when. Complete it with what was available. Do it in a way that could have been - and in line with the Campagnolo spirit. And no buying of parts or labor.

Put yourself in the position of working at Campagnolo in 1983. You are one of the guys (or girls) at the Campagnolo race support team. You have recently understood that aero routing is the new “it and in thing”. You know that after Tullios death the research and development guys and girls are working on a new group – the Record 180/C-Record and that aero brakehandles are soon to be standard.

Your boss (who has a striking resemblance to Vito Corleone) tells you to hustle up something to address this new “aero craze” thing and getting it out to the pro teams – pronto! “No money and absolutely no new tooling! Basta! Make it for both bullhorns and road bars – and have a solution ready at the end of the week! BASTA!”

You realize that to keep your job you have to make something out of nothing. No money and no time. You get out the spare parts catalogue. Hmmm… let us see what is in here. What parts are contenders? Get the brain going! Two double espressos going down quickly.

You soon realize the time trial aero routing is easily sorted. You solve it in a couple of minutes. You go down to factory floor and get a cyclocross chain ring bolt and a rear hub spacer from the line. Add nylon washers from the down tube shifters and - presto! If really anal about how it looks drill the handles to get the chain ring bolt and nut to seat a 1 millimeter on each side. Drill the body. This was easy. You suddenly anticipate a raise in salary from your boss – and maybe a date with his beautiful daughter.









All measurements are correct and matching (the nylon washers actually needs to be drilled from 9 to 9,9 mm and to be thinned out a bit also).

As I am not building a TT bike I am not going to drill a brakehandle body just to show you (have a look at part 1 to see where it should be placed. It is quite simple and straight forward.

Realizing the boss´s orders were a solution for road bikes also you start going thru the spare parts catalogue once again. Let us see… what contenders are there?! A couple of minutes later you have decided to investigate the following parts further. They have potential.
  1. An SR jockey wheel bolt/sunk screw and its nut together with a brake adjustment nut - minus its rubber ring.
  2. A bolt that normally holds the rear derailleur parallelogram return spring in place and a brake adjustment nut.
  3. A brass/bronze bushing for the rear derailleur and a steel jockey wheel sliding bearing.



Measuring begins. You are happy as a child on Christmas! They all seem to fit the bill.









Now you can not only look forward to dating your boss’s daughter - you might even get to marry her! And the salary will skyrocket!

Your happiness gets a knock when you realize there has to be a change in the production. The tooling for the brake handle body has to be changed a tiny bit. To add the possibility to drill the body and to get a cable housing ferrule to fit. Maybe not marry her then. Back to holding hands…

Last edited by styggno1; 08-14-18 at 01:27 PM.
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Old 08-14-18, 12:56 PM
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Part 4 (of 5)

After some careful measuring and thinking you decide on the rear derailleur bushing with a jockey wheel sliding bearing. One big advantage with this combo is that it makes it possible to place the cable as far up and to the front as possible within the given dimensions of the brake handle and body. This gives leverage. There are other strong reasons for this combo. The bushing is cheap (remember we are making belief here – this guy had the whole factory to his disposition – today these bushings are unobtainium), it is both light and strong (it is a tube) - and when mounted with a tight press fit and then gently riveted/enlarged in both ends – nothing protrudes on the sides while still being securely mounted. The jockey wheel bearing is chosen – because it is a bearing (even if it is actually the outer side that is the bearing surface), it is steel and it has a groove for the cable (oil/grease groove when at the jockey wheel). It is also exactly wide enough to support the bearer, the bushing, from side to side, while still free to rotate on the bushing. The fit between them makes your eyes water out of joy. It is like someone had this in their mind making them. We are talking 1/100 of a millimeter and yet it spins freely.

The only thing against this combination of parts is that there is no “Brev”, “Patent” or “Campagnolo” on them. One could contemplate the rear derailleur bushing together with a brake adjustment nut but it falls on the nut being a bit too large for it to fit. Believe me - I have measured over and over again and it does not work. It is 2 mm too big. It hits the bushing for the cable end anchor or the front of the handle – or the body at the back. There is not enough room for it. It is also a nut. It has threads – it would feel mish-mash and maybe in the long run not OK together with the brass/bronze bushing - and it would not support the bushing much. But it would be chrome and it would say “Campagnolo” right there on its side. I like that. Close but no cigar. The other pin/bearer alternatives, the SR screw and nut and the spring holder bolt, fell on appearance. Too much is going on. Not discrete enough. The spring holder bolt fell late as it would replicate the Campagnolo made handles on one side. Drilling and tapping the lever inside hole for the bolt threads and having just a tight support hole on the outside. But in the end the tubular bushing won.

Back to our Italian friend at the Campagnolo race support team. He ponders what the boss is going to say about that change in the casting mold for the body. “He is never going for it.” “I am not even going to get to hold hands with his daughter.”

About a year later little Fausto is born though. Everyone is happy and the grandfather (who still looks and sounds like Vito Corleone) turns to you and says – “I gave you an offer you could not refuse. You delivered. It was a good solution. It worked. Tullio would have approved. I know the new group set is out now and your parts are obsolete. But you did deliver. You are in the family now. Welcome. We will discuss more after dinner – I have some ideas about an adjustable slant parallelogram rear derailleur...”

-----------------------------------------------------------------------

Making these brake handles has been fun. I had to use my imagination, my tools and my spare parts. I believe my solution is good looking, I know it works great (tested) and one can at least imagine that Campagnolo could have done this. And/but I did it - my way... and there is satisfaction in that.

The most difficult part of building an “aero conversion Campagnolo Super Record equipped 3Rensho Super Record Aero” (that is sort of fun...) is now solved. My comfort zone has been challenged. The rest is easy. What other rules do I have to put up for myself!? Getting a silver anodized Cinelli 1R stem, 110-120 mm, with “3Rensho” pantographing before I can start the build up? Hmmm. That would take a while to get hold of. I will bet making one would be faster. Just kidding! Seriously!

Lever work pictures:

Starting off with my favourite tool during this project – it was used a lot!



And another nice tool – the spring loaded punch. More control than with a normal punch and a hammer.





Do not forget to put the roller in before using the press to fit the bushing... ;-)







Body work pictures.





It is very important to get a good seat for the cable housing ferrule. It is crucial. Old Campagnolo ferrules are a little rounded at the end and 6 mm. The seat has to be a tight press fit for the ferrule. No wiggle room. Remember that your hands are going to be on these when on the hoods. The ferrule has to be supported along all its length i.e. – flush with the body.


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Old 08-14-18, 12:59 PM
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Part 5 (of 5)

The end result.




I hope you have enjoyed the ride.


.
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Old 08-14-18, 01:28 PM
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Great details and info. The commentary on limitations sounds familiar. Whether it be a budget, fabricating something, or doing as much as you can with as little possible, the challenge is a fun part of the journey. Looking forward to seeing this completed.
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Old 08-14-18, 02:07 PM
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Mavic made cable guides that were J shaped tubes that go form the top cable stop on the non-aero brake lever bodies and on to the ends of the bullhorn handlebars and routes the cables into the handlebar. The brake cables the emerges though holes near the stem.
seen them for sale at eBay but never saw them installed on a bike yet...
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Old 08-14-18, 02:19 PM
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Originally Posted by Chombi1 View Post
Mavic made cable guides that were J shaped tubes that go form the top cable stop on the non-aero brake lever bodies and on to the ends of the bullhorn handlebars and routes the cables into the handlebar. The brake cables the emerges though holes near the stem.
seen them for sale at eBay but never saw them installed on a bike yet...
Yes, they did. And the tube - what did it do... It created a 180 bend...
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Old 08-14-18, 02:24 PM
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Originally Posted by styggno1 View Post
Yes, they did. And the tube - what did it do... It created a 180 bend...
A smooth, consistent bend though, that won't move and kink on you. Similar, I think to a cable bend at the BB for a front derailleur cable...
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Old 08-14-18, 02:30 PM
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Smooth bend but short radius and the force (and moderation need/feel) differs a lot between a brake and a shift lever. There might have been a reason for them (Mavic tubes) not very often being used. My point is - if wanting to go aero with old brake levers choose the sollution that fits your purpose.

Edit - adding - Why point the housing and cable in the opposite direction from where you want it to go?
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Old 08-14-18, 06:03 PM
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Originally Posted by styggno1 View Post
Smooth bend but short radius and the force (and moderation need/feel) differs a lot between a brake and a shift lever. There might have been a reason for them (Mavic tubes) not very often being used. My point is - if wanting to go aero with old brake levers choose the sollution that fits your purpose.

Edit - adding - Why point the housing and cable in the opposite direction from where you want it to go?
Very nice work/workmanship.
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Old 08-14-18, 06:15 PM
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Maybe you could mount the brake levers upsidown so the cables will always follow the bars towards the stem....
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Old 08-14-18, 08:07 PM
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Beautiful work! I loved the writeup, too. Thanks for sharing.
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Old 08-14-18, 08:18 PM
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Great stuff. So do the hoods happily sit over the housing and ferrule or does it stuff up the fit?
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Old 08-14-18, 08:39 PM
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As a nuts and bolts problem solver I'm loving this thread!

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Old 08-15-18, 12:03 AM
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My version

Johan,

Smoothly done -- looks pro! I love all the research you did and shared with us. And the story, very entertaining.

Here's mine:
I don't have 10 posts so I'm not allowed to post photos or URLs, so lets try this: Put the following back into the format of a Flickr URL and paste it in your browser.
h t t p s (colon slash slash) flic.kr (slash) s (slash) aHsmohSKJc

I modded these levers in the mid to late '80s and I thought they worked great. I probably raced them in over 100 races (I didn't count), and it was frequently my training bike too. Regular drop bars, not bullhorns. I never really got tired of them, just eventually sold the bike they were on (after removing my modded levers) and never got around to putting them on another bike.

Mine are better (IMHO) than most pulley-type conversions because my pulleys were larger. So large that the front of the lever has to be milled out to make room. As you may know, the tendency of a "wire rope" (brake cable) to fatigue when actuated over a pulley depends on the ratio of the diameter of the pulley to the diameter of the cable. In aircraft that used cables to actuate the flaps and such, the minimum ratio was 50 to one. So for a 2 mm cable the pulley should be 100 mm (4"), for a setup that will never fail in fatigue.

I decided to settle for a setup that would fatigue the cable eventually, but would give acceptably long life before that happens. That cable is very easy to inspect there, especially on my modded lever with that slot milled in the front of the lever, so I knew I'd see it when it starts to fray. They don't break all at once.

The other improvement on mine was a sealed cartridge ball bearing, to minimize friction.

You will notice the cable runs on a flat cylindrical surface, no vee-groove. No problem, it worked fine for this application. The vee-groove is mostly there to keep the cable centered, but on my levers, the cable never drifted, it only wanted to go straight down the middle. One possible enhancement would be to make the cable-facing interface of the pulley a U-groove that closely matches the diameter of the cable, to support the round shape of the cable -- might reduce tendency to fatigue. But that wasn't necessary in my experience.

The bolt that holds the pulley/bearing was made from a seatpost binder bolt, similar to the Campy part no. 1072, only made of stainless steel so I didn't have to have it plated. I forget who made the SS pinchbolt. Italian I think, maybe Silva?

As far as leverage goes, I didn't measure it but my subjective feeling is it was a bit higher leverage than stock. That is, you have to pull the levers further, but you get more braking power. It means you need to keep the pads adjusted a bit closer to the rim, so you don't risk bottoming out the lever on the handlebar. It wasn't like night and day though, pretty near the leverage of the stock lever.
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Old 08-15-18, 07:57 AM
  #46  
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Bulgier!! (I know it is you)
There is a a line of former employers that want to talk to you. They want to discuss the countless hours you have stolen from them. All the hours I should have worked instead of studying your bicycle catalog pages. They are not happy.

Jokes aside - thank you for all those hours of fun - doing reseach thru the material that you have provided access to!

Your handles look very nice (I hope a moderator could/would make them visiable here) and your experience of them valuable. Interesting that the lack of groove means so little (or nothing) - I would not have believed it if it was not you who said it.

I agree with you that size matters... That is one of the reasons I tried so long to get the brake adjuster nut to fit. The other reason being the chrome and "Campagnolo" on its side. Wanting the cable routing with cable and housing on top of body (what I believe to be the road bar solution) made it impossible though.

My version - when measuring the jockey wheel sliding bearing circumference, where the cable sits, it is only tenths of a millimeter smaller than the roller/pulley Campagnolo used for their team issued handles. And its groove is exactly the right size for the cable - and I hope that delays fraying enough for it to be usable. All this is academics though as the 3Rensho is not going to be a daily user. My build will be done as if someone built an aero bike back then and it would not have been a daily user then either. A "enlighted" builder/owner who knew what he wanted and in that also knew what to look out for when using it (brake cable security and the Roval wheel spokes).

I am really glad to have got the opportunity to thank you for your contribution regarding the catalogs and thank you for your kind words about my version conversion!

Last edited by styggno1; 08-15-18 at 08:10 AM.
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Old 08-16-18, 03:24 PM
  #47  
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Originally Posted by P!N20 View Post
Great stuff. So do the hoods happily sit over the housing and ferrule or does it stuff up the fit?
Thanks!

The hood are mounted on the brake handle body first (of course). Then the cable is run from the lever and in thru the body and out from under the hood. Then you use the cable to guide the housing and ferrule into the ferrule seat. Tweaking it in - and pushing the housing and ferrule to its stop. It has to seat properly.


The hoods stretch over the cable housing and ferrule with ease if the hoods are fresh and supple. I am running out of those and tested with an old one that was a bit torn. It worked but it was scary. The extra height of the handle body feels nice for me as it fits my hand size better than the original slim profile. I have not done enough real riding with them though as my tests were done on a mock up bike on a Tacx VR trainer - and braking was because of that done only in the rear. The rear brake was the most important to test as it has the longest cable/housing causing friction. To be able to tell if the cable feels uncomfortable sitting there on top of the handle - more real riding has do be done. Personally I do not believe there will be any problem as I do not support my upper body weight much by my hands. Elbows are never straight and stomach and lower back doing the job.
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Old 08-16-18, 05:41 PM
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To simply say "wow!" is an insult. You have raised the bar, with your story telling as well as your technical savvy. Absolutely perfect solution and amazing execution! Love that you used only Campagnolo pieces.

Can I ask, did you use a mill or a drill press to drill the hole for the cable housing side of the lever base?

Originally Posted by styggno1 View Post

I beg you not to hold off completing the 3Rensho to try and source a pantographed Cinelli stem. I've been watching 3Rensho listings for several years and have only seen 2 come up and both ridiculously expensive.

Keep up the great work! Can not wait for the next update!
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Old 08-19-18, 02:41 PM
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Originally Posted by shnibop View Post
To simply say "wow!" is an insult. You have raised the bar, with your story telling as well as your technical savvy. Absolutely perfect solution and amazing execution! Love that you used only Campagnolo pieces.

Can I ask, did you use a mill or a drill press to drill the hole for the cable housing side of the lever base?

I beg you not to hold off completing the 3Rensho to try and source a pantographed Cinelli stem. I've been watching 3Rensho listings for several years and have only seen 2 come up and both ridiculously expensive.

Keep up the great work! Can not wait for the next update!
Thank you very much!

This is difficult in English - I first used a milling bit (in a drill press) to get a somewhat flat surface (with the small drilled hole in the center), then a drill to make the ferrule seat - and last a bit of free held Dremel to blend things out. I have got an old 50ies Arboga precision drill press of (cast iron - weighing a lot) that used to be at a Swedish SKF factory. It is wonderful...

About the pantographed Cinelli - I know, I have been keeping an eye on auctions for a long time too. That is why I wrote "I will bet making one would be faster. Just kidding! Seriously!"

I really want one... What I meant was ...making one (myself) would be faster. The winter is long over here.
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Old 08-22-18, 02:07 PM
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Tonight I cleaned up some headsets. Some NOS and some not. All of them being hot looking though. I always start with the headset when building a bike (of course). When it is mounted the frame and fork are "married" and can be handled easier. Looking forward to installing a set. Maybe tomorrow or during the weekend...


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