Velocivixen

I bought a circa 1980 or 1981 Lotus Grand Prix mixte off CL yesterday. I may enter it into the clunker challenge, so won't post the whole thing here.

I noticed that the front center pull brakes are Shimano "Tourney" and there is a metal arm which acts as the drive side straddle arm. On the back side is a flat metal tab which activates a quick release. I've included photos. I don't see any date codes yet, but once I take it apart for maintenance I will look.

What can you tell me about these? I've never seen them before and I like how they work. Very elegant and clever. Anyone know what year they might be?

Shimano Tourney Center Pull Brake by velocivixen, on Flickr

Back Side Shimano Tourney Center Pull by velocivixen, on Flickr



EDIT: I did see some photos of these on this side and a few others. I understand they're likely early '80's "sport" model type. I just think they're interesting. Wondering how many of you see these often? How they perform, etc.


Shimano Tourney Center Pull by velocivixen, on Flickr


Shimano Tourney Center Pull by velocivixen, on Flickr

Andy_K 

I don't know anything about them, but I like that a lot!

I was nearly pulling my hair out last week trying to get a set of Weinmann center pulls properly adjusted. I couldn't see any way that a person with less than five arms could do it without a lot of frustration. That Shimano design looks much easier to use. I'll be very interested to hear how they perform.

VeloBase has an entry for your brakes, of course: VeloBase.com - Component: Shimano Tourney - center pull
The also have Shimano 500 and 600 variants. The dates don't seem to match your bike, so maybe someone liked them enough to install them as an aftermarket upgrade.

willydstyle

I was having that same problem, so I just took them into the shop where the mechanic used this:

https://www.amazon.com/Park-Tool-Han.../dp/B003J7O7MS

and I was amazed by how quick it made the process.

I do love the performance of these old Weinmann centerpulls though. So much better than the Dia Compe 500 sidepulls I used to use.

Andy_K 

I have one of those, but I couldn't figure out where to put it make this easier. I use that tool mainly for tightening zip ties.

willydstyle

I'm not sure how to use it either, my eye wandered to the case full of vintage derailleurs and he was done by the time I looked back at the stand.

Velocivixen

I have a park tool cable puller also. I think it's called a "third hand" or maybe a "fourth hand". Anyway on center pull brakes you'd have the typical straddle cable over the metal straddle cradle (?). Then the brake cable that comes down from the front brake lever goes through the back of the straddle cable hanger and uses a pinch bolt situation to fasten it. With the front wheel OUT of the bike, use the Park cable puller tool to pull the brake cable to raise the carrier then tighten down the bolt (while still holding the cable pull tool).

You know....a picture's worth a thousand words. So if that doesn't make sense, I understand.

Andy_K 

Thanks but, yeah, I'm still a bit confused. From what you wrote, doing this with the wheel out is probably an important part of what I was missing. I didn't think to try that. I was trying to (1) pull up on the straddle cable, (2) pull the brake cable down to get it tight, (3) hold the nut on the back of the yoke, (4) turn the bolt on the front of the yoke -- all while trying to eyeball the pad clearance at the rim and keep the cable from slipping out of the lever. I eventually got it dialed in enough to stop well even with steel rims but not without throwing a few temper tantrums first.

Anyway, I really didn't mean to hijack your thread. I was just observing that the design of your brakes looks like it would make the whole process easy while throwing in a quick release as part of the bargain. I hope someone responds on topic and can tell you something about these Shimano brakes because I'm very interested.

seedsbelize 

I like that, and will keep an eye out for it.

Velocivixen

@andy k - another way I do it is to have the wheel in and squeeze the brake pads against the rim with a locking clamp. Then I pull the brake cable through the pinch bolt on the back of the straddle carrier and tighten best I can. Still seems like you need more hands, but clamps help.

Grand Bois

It's a fourth hand and why take the wheel out of the bike?

dweenk

I just use a clamp to put the pads against the rim and then use the adjuster to allow for the rim side-to-side tolerance. In my opinion, center-pulls are quite easy to adjust and center without special tools.

Iowegian

As GrandBois said, it's a 4th hand tool and it can apply a lot of pull on the small amount of cable past the fixing bolt. A third hand tool is a sort of springy thing that functions as a clamp to hold the pads against the rim. You could probably get away with using one or the other but if you can round up 4 hands, might as well use them all

Andy_K 

I'm so sorry for derailing this thread.

Velocivixen

@andy k - you're not responsible for how people choose to respond. No worries.

I just wanted to know about the brakes. I've never seen them before.

noglider 

I saw these brakes back in the day. I was a bike mechanic. I worked on a few. They didn't seem better in any way, and my vague recollection was that they were slightly disappointing.

old's'cool

If I understand the mechanism properly, the cable to the non drive side (in the photo) caliper has to slide through the yoke connected to the drive side caliper as the brakes are applied. That will add friction that is not present in more conventional designs, if I'm not mistaken.

T-Mar

The subject brakes on the OP's bicycle were called a "link-type centrepull calipers" by Shimano. They were introduced in 1977 on Tourney and 600, though only Tourney got the release mechanism, as 600 had the quick release built into the levers. In 1978 a 500 version was added. The 600 version was dropped in 1979 and the 500 and Tourney versions were gone by 1980.

The prime objective was to facilitate caliper set-up. While it allowed the caliper to be set up with only two hands, it also fixed the yoke length, so that inexperienced mechanics could not inadvertently alter the mechanical efficiency and adversely affect braking performance.

Shimano would reintroduce the concept on cantilever brakes in the late 1980s, when ATBs became popular and it would eventually lead to V-brakes in the early 1990s.

Jeff Wills

Yes to all the above. Also, remember in the late '70's-early '80's, Shimano was trying to improve its market share by making its parts "different". The patented "straddle arm" was part of that strategy. I saw a couple in my bike shop days, but they were a rarity.

In that time, Dia-Compe, Sugino, and SunTour were much more common than Shimano and all of them trailed corresponding European manufactures: Weinmann, Huret, etc. The "different" parts philosophy culminated with the "aero" AX parts groups... but those were quickly steamrolled by the mountain bike boom. Once Shimano introduced SIS index shifting, with their matched shifters, derailleurs, freewheels and so on, they were in able to leverage their market share into dominance thanks to their competitors' inability to come up with anything as good. By the early '90's it was almost all over. Other manufacturers have recovered some, but Shimano still dominates.

Regarding the tools: the "third hand" tool holds the brake shoes against the rim so the mechanic can tighten the cable clamp bolt. It works on both centerpull and sidepull brakes. The "fourth hand" (aka zip-tie tightener) puts tension on the cable and steadies the straddle yoke so the cable clamp can be tightened. We'd never remove the wheel in the shop- the object is to get the job done quickly, using as few steps as possible.

gugie 

I've had the similar Hozan 4th hand tool for as long as I remember. I even use it on derailleurs to snug the cable up before tightening.

Bicycle Addict

I adjust the same way VV, it is easier with wheel off as you have slightly more room, I also at times do this while adjust Canti's, both of which are good braking systems, V Brakes do have a better feel, but also flex under hard braking giving the illusion of greater brake pressure at the lever.

Very cool brake design on that bike VV, you should totally get it going for the Cliunker 100, lube it pump up the tyres and adjust cables and see how far you get.

Bicycle Addict

Try using a toe clip strap to pull the lever in so the pads are close enough to the wheel, then use a clamp to hold the pads nowhere they are close in near the rim, adjust the cable(with more ease now with not so many things to do all at once) undo the clamp on the pads and adjust pads to where you want them. It will become easier.

Now I am going to leave her thread before she slaps me for thread jacking.
Sorry VV! Lol

T-Mar

Yes, Shimano was trying to increase market share with new features but these features were not just for the sake of being different. Sometimes they missed the mark for market appeal, but the changes were always grounded in improvements to reliability, performance, safety and convenience.

Convenience is often overlooked, especially when it relates to LBS assembly but this was a major consideration for shops. Bicycles which were quicker to assemble were more popular with shop owners, as they retained a higher share of the profit margin and allowed mechanics to spend more time on repairs, where the margins were higher. Any bicycle incorporating a feature that facilitated assembly was more likely to be ordered by a shop, provided it offered similar equivalent performance to the competition and did not result in a significant price increase. This encouraged the bicycle manufacturer to spec these components, which increased the component manufacturer`s market share.

paulkal

I have the Shimano 500 version on my commuter bike, they work ok, not much different from side pull brakes.
They are a bit easier to setup.

Velocivixen

Good morning all, and that's for the insights. I know what @T-Mar means referring to the early '90's Trek MTB's I have ('91 Trek 950 & '95 Trek 820), with the Shimsno link system and the pre lengthened straddle arm.

Only the front brake has this. The rear is the same but without the QR.

willydstyle

That's disappointing to hear, as my experience with vintage centerpulls and sidepulls leads me to enjoy the performance of the centerpulls much more.

Looking at the design it makes sense, though. I don't think much of the force that is being applied to the brake cable will be applied to the rigid arm that straddles the brake cable.