cstar 

Hi all,

I love vintage road and touring bikes, so I am absolutely thrilled to be sharing my very special recent find with others who can appreciate it: a late 70s or early 80s(?) Tsunoda Saturn. I'm hoping to glean as much information as possible about this beaut. My initial attempts to find information have been fruitless. I did find one page from a vintage Tsunoda catalog but its all in Japanese. I am lightly familiar with Tsunoda, previous to this bike I knew that Tsunoda made bicycle frames for other brands. This is however, the first Tsunoda branded bike I've seen in the wild. Seems to be a mix of early Dura Ace stuff. The only bummer is that the front wheel is a replacement. The rear is tubular, with a Dura Ace hub and Mavic rim. The color is awesome, and is actually lightly metallic.

Despite the whole frame being chromed and it being a rather old steel bike, my scale clocked her in at 21lbs even!! I was blown away by the weight. I took it on a very short spin up and down my street, and it was a real pleasure. Seems like a decently nimble bike, but then again I am used to riding heavy stuff (my ProTour is like 26lbs and my Surly is like 28lbs)

Some of my specific questions are...

Is this exceedingly rare?
Any idea what the frame tubing is? I saw a few other Tsunoda Saturns on Google with Ishiwata 019 stickers. Is that a fair guess?
Any idea what the TU or other stickers mean? Old Tsunoda catalogs also have this TU logo
The rear and front brake calipers are both Dura Ace but look like different generations/groups maybe? Is it likely the mismatched calipers are original spec for some reason? If I wanted to match them, is one style better than the other?
Did Tsunoda make the Centurion ProTour15? I also have a Protour and some details of lugs etc seem very similar between the bikes and other Centurions I've seen

My plans...

I will be completely disassembling it and cleaning and re lubing everything.
I want to do a cream and white harlequin bar wrap with cotton bar tape.
Are there replacement hoods of any brand that fit reasonably well on these Dura Ace levers?
New brake pads (is kool stop continental my best bet for replacing the current pad/holders?)
New brake cable housings, probably clear ones, although part of me feels like celeste colored ones could be fun... I do have a single celeste Blackburn bottle cage too
I am hoping to find a 36 hole Dura Ace front hub to match the rear, and lace both hubs to an appropriate looking clincher rim set (I would love rim suggestions!)
Folding gumwall tires

Hope some of you will enjoy this -Chris

Highmass

Cool find Chris. It looks like it has potential to become a really nice bike.
To me the group, looks a little like a mix of first and second generation Dura Ace. The rear brake is a first generation, and the front brake is a second generation. I can´t tell you, if one is clearly better than the other. What I can say, is that I have a set of first generation, and I was plesantly surprised when I tried them. To me the rd looks like a first gen, as the upper pulley wheel should be metal on the second gen (But a good cleaning might reveal it to be metal when all the goo is removed). The brake levers looks like second gen to me, as the earlier ones had more holes (Smaller and round). I´m pretty sure some Dia Compe hoods will fit.
As far as I know, the second genration of Dura Ace became available in 1978. If the parts on the bike are original, I would assume it to be made during the transition from first to second gen. So probaply around 1978. But it should be quite easy to confirm or refute my theory. Look up Shimano date codes on the net (Here https://www.pedalpedlar.co.uk/blogs/...ano-date-codes for instance), and you can see when many or possibly all the components was manufactured.
Anyway, nice find. I´m looking forward to see your progress.

juvela

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a beautiful bicycle and a most excellent find!

regarding information search -

you might consider taking look at the parallel year Lotus materials

likely you shall find a match as the company was the producer of that marque also


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Feldman

Components put that @1976-1980 as per the Dura Ace EX components. Great stuff hung on s handsome frame.

genejockey 

I love it! I have a somewhat newer Lotus Supreme, with a frame brazed by Tsunoda, and the full 7200 Dura Ace group. I don't know why, but I really like these quality Japanese bikes from the era when Shimano was just moving upmarket. Are you sure the whole frame is chromed? My Supreme had a lot of chipped paint, and while large areas had paint over chrome, others nearby were clearly just paint over steel, as if they'd only dipped part of the frame when they plated it. The head tube lugs were chromed, and the drive side chainstay, and both dropouts. The fork was all chromed, then painted over leaving the crown and dropouts.

You're right. This looks like first generation mixed with 7200. The front calipers are 7200, but the rear looks like first generation. The levers look like 7200 blades on first generation bodies - which may explain the jury-rigged reach adjustment.

The derailleurs look like 7100 r 7200. Not sure what the difference is. Crankset looks like 7110, but I think 7110 is pretty much the same as first generation except for the chainrings.

As far as hoods go, I'm currently using Dia Compes. on the 7200 levers on my Lotus, and they fit well. The one issue I have is the brown ones are just that - brown. Opaque brown, as opposed to the translucent amber of real gum hoods. Still the levers are like 40 years old, so I'm not complaining!

Brake pads - I put Kool Stop's TripleLite Dura shoes on my Lotus, because they're a little more like the originals and work with the wheel guides which turn out to be important for getting the retaining bolts to tighten down all the way.

Brake cable housing - I've seen bikes from the early 80s with Dura Ace with gray cable housing, so you could probably get away with doing what I did on the Lotus Classique I just restored - use Jagwire housing, and cables, which may be a little less prone to compression.

T-Mar

I'm going to place the bicycle 1977-1978. It it has three components not released until until the 1977 model year; the Dura-Ace rear derailleur, the 2nd version of Dura-Ace front derailleur and the brake levers with the slotted holes and horizontal embossing. The derailleurs are not the EX versions introduced circa August 1978. There are two components that are later. First is the EX front caliper but given that that it is mismatched with both the rear caliper and the levers, it would appear to be a replacement. Second, the chainrings are the extra-lightweight version introduced circa May 1978 but chainrings are a consumable, so it could still be 1977.

As for the tubing, the best indicator of the tubeset, is the seat post diameter.

I've collected serial numbers from dozens Centurion Pro-Tour and have yet to see on with a serial number that suggests Tsunoda..Most lugs are not proprietary items, but standard off-the shelf product from companies that specialize in lug manufacture, such as Eisho, Kobayashi, Otsuya, Yamazaki, etc.

cstar 

Hi everyone-

A big thanks to all of you for the wealth of information!

I am very much a Suntour fanboy so my expectations for this very early Dura Ace were low but I was pleasantly surprised by all of it on my quick test spin. Great feel. Has me re thinking my feelings about the early Shimano upmarket stuff 🙂

Yes, remarkably the whole frame is chromed! Every single spot where there is a chip, bright shiny chrome shows through. I have also seen other bikes where just the fork and stays were plated, but that is not the case here. Of course, the chrome showing through on the main tubes is not finely polished, I'm sure only the fork crown and head lugs got the proper prep and finish work to get a very smooth finish with the chrome. But none the less, I am impressed with the full chroming and just thrilled to have some extra protection.

It's worth noting that on my ProTour, which also has an entirely chromed frame, the plating underneath the painted sections seems much smoother than it is on this Tsunoda. It's like they almost polished the whole frame of the ProTour to the same extent as the fork crown and other exposed bits. Always amazes me.

T-mar, thank you for sharing all your knowledge! Its not the firat time you have shone light upon a bike that was otherwise a mystery to me. I really appreciate it. I believe an old post of yours is what helped me decode my ProTour's serial number. Would you like my serial number to add to your records?

I'm getting a but off topic here and for that I apologize but do you know who actually made the ProTour frames?

cstar 

Also, I will measure the seatpost with my calipers tonight.

If we could take a guess at the tubeset based on that, I would be ecstatic! Fun to know these details if possible.

T-Mar

Thank-you for the offer. I'm always receptive to serial number submissions. I've only seen one pre-1980s Tsunoda frame and the serial number format did not match that used in the 1980s. However, it was an oddball quadricycle, so it may have been sub-contracted.

When you say Pro Tour, I assume you are talking about the Centurion model, as opposed to the chain store private brand? If so, there were multiple manufacturers. Without referring to the database, I recall at lest three. The 1970s version that have surfaced were manufactured by Miki of Japan. In the early 1980s Tano was the manufacturer, with frames sub-contracted to Nomura of Japan. Circa 1984, for some unknown reason, the model was manufactured by Matsu****a/National (of Panasonic brand fame) before reverting to Tano/Nomura. The serial number should tell us who built your particular frame.

T-Mar

There's a good probability that the diameter is marked on the seat post. Generally, it's below the minimum insertion mark.

T-Mar

I've been giving this some thought and believe it may simply be Tsunoda's trademark symbol. At one time, it was common practice for Japanese companies to use a two or three character, Anglicized, alpha or numeric symbol, rather than the full company or brand name. This practice stems from the early days of the Japanese bicycle industry, when companies mimicked the BSA symbol used by British Small Arms, a bicycle company revered by the Japanese.

Examples of some of the better known trademark symbols used by Japanese bicycle companies are;

Maeda - 8.8.8
Shimano - 3.3.3
Sekine - CS
Kuwahara - KCL
Hokoku - HKK
Eisho Seisakusho - ES
Mikashima - MKS

Consequently, I believe that TU may simply be the trademark symbol for Tsunoda.

MauriceMoss

The letters "TU" were used extensively in Tsunoda's marketing campaigns that were apparently very successful in Japan (if you search Japanese blogs you'll run across many people remembering the "Tsun, tsun, tsun, Tsunoda" commercial jingle).
Maybe some Japanese speaking members could chime in on this (as I don't speak or understand Japanese), but in the commercials I've seen, 'TU' usually seems to be pronounced a bit like 'teh-you-go'.


The only explanation of "TU" in Tsunoda's badges and branding that I've ever come across (and that's both on the Japanese wikipedia page for Tsunoda and on a number of random Japanese blogs), is that it's the first two letters of the original spelling of the name - TUNODA. Here is a Google translation of the paragraph on the Japanese Wikipedia page:


Here's a commercial for a Sky Lancer, which must have been on every kid's wish list...



Aside from the "T.U" on the Saturn head tube decal here, there was also a logo where the T was behind the U and it looked like this:







A sign with the original spelling - TUNODA, along with the old TU logo.

cstar 

Thanks T-Mar and MauriceMoss for all that super cool info! I'm very grateful for all of it.

T-Mar I will send you the serial number of my Centurion ProTour and this Tsunoda when I get around to it. Hopefully this weekend.

cstar 

The seatpost size is 26.8mm, both by my calipers and marked as such.

if this indicates a tubeset to anyone I'll be so thrilled to know!!

T-Mar

Most tubing manufacturers used single butted seat tubes and that's a small post for a high grade frame of the era, if the seat tube was single butted. Consequently, I believe it's a Tange tubeset, as they did use double butted seat tubes that required smaller posts. Tange Champion #1, #2 and #3 all used the same seat tube, which had a nominal inner diameter 26.8mm. Standard clearance for a seat post is 0.1mm radially, so a 27.0mm inner diameter would be typical for a 26.8mm post. While the spec inner diameter is slightly small, a standard reaming operation could result in it being appropriate for a 26.8mm post. Of the three, Tange Champion #1 would be most likely. The other possibility is Tange Champion Pro, which had two seat tube options, one being 27.0mm nominal inner diameter.

cstar 

^^^ So awesome, thank you for that info!

I have had a few Tange 1 and 2 bikes and I am fond of it so that is very welcome news. Though I have to admit I was very excited by the proposition of it being something unfamiliar to me, like Ishiwata. I looked carefully at the paint and it doesn't look to me like there were ever tubeset stickers on the bike... Can anyone guess as to why Tsunoda would opt to not put tubeset stickers on what was presumably one of their highest spec'd bikes of the time?

How certain can we be that the tubeset is Tange 1; would it be inappropriate to buy Tange 1 decals and put them on? I don't intend to sell it so I don't think I'll be misleading anyone. I would just like to display the tubeset proudly 🙂

I need to befriend someone who can read Japanese, maybe they could decipher the catalog page for me!

cstar 

This is the catalog I've been looking at.

The catalogs of Japanese vintage bicycle

cstar 

The only other Tsunoda Saturns I can find by googling seem to be in Japan, as I found them on what seems to be a Japanese blogging website. I feel like this might be a pretty rare bike to see in the US.

For what its worth, the closest example to mine that I found was a few cm bigger than mine and the owner said their's was Tange 2. Just a little more possible support for the Tange 1/2 guess.

T-Mar

It's possible that one of the existing decals may be a tubing decal. It was fairly common practice for the bicycle manufacturers to apply their own tubing decals, as it gave the impression that the bicycle manufacturer was producing their own tubing. Sometimes, these tubesets were simply relabelled and other times they were custom drawn to the bicycle manufacturers specs. The only Japanese bicycle manufacturer that actually had their own tubing mill to produce high grade, butted CrMo tubing was Miyata.

Bridgestone and Fuji both used Ishiwata tubing but labelled it as their own brand. Other companies such as Maruishi used a generic label, not mentioning their name or the source. The practice extended beyond the manufacturers, to contract manufactured brands such as Nishiki and Specialized. There were many others in addition to the handful mentioned. The practice diminished in the 1980s, as consumers became more knowledgeable and started to question what tubesets these decals actually represented.

I have seen a Tsunoda Saturn with a tubing decal. It was for Ishiwata 022. Your current post is two sizes under what I would expect for 022 and the seat tube wall would be very thick for an Ishiwata set (assuming the post is not undersize for the frame). Tsunoda is also known to have used Columbus tubing on a few high grade Lotus models that they contract manufactured in the early 1980s. Like Ishiwata, Columbus employed a single butted seat tube and the current post size is small for a butted Columbus tubeset. The appropriate Columbus tubeset based on the post size would be plain gauge Aelle, which I would be atypical for a bicycle of this level. Tsunoda also used Tange on some higher enf Lotus models of the era.

One thing that you can do, to increase your confidence in the tubing manufacturer, is to remove the fork. Typically, the steering tube will be stamped with the manufacturers logo and, if it's a stock fork, it may even have a date code. It's rare to mix fork and frames from different tubing manufacturers at his level so if the fork is Tange, the frame almost certainly also be Tange.

The 1980 Lotus catalog at least corroborates that the subject bicycle is pre-1980. as the EXK version (with the chromed lugs) uses the Dyna-Drive crankset and pedals that were introduced that year.

cstar 

Wow, I really can't thank you enough for all the info.

At some point I will definitely be disassembling the whole bike to clean and service it, so I will be sure to check the steer tube 👍