aprieto28

I recently picked-up a very clean Kuwahara Adventure tandem. Looks all original except seats, which are newer selle Italia Bianchi. it's pink with rainbow colors, 5 or 6 different different colors. Does anyone know anything about this bike. I have never seen one like this before on the road before. I wish I could upload a picture, but appears that they are too large for this forum and I haven't been able to figure out how to make them smaller yet.

aprieto28

Here she is.
Made in Osaka Japan.
4130 Chomoly tubing.
Arai drum brake.
Ukai 27 in. wheels w/ sansin seal bearing hubs.
Nitto Olypiade handle bars.
Technomic stems.
Selle italia saddles.
Diacomp drikked brake levers.
Suntor handle bar end shifters.
NG0982 brakes?
Sunigo GP cranks.
18 speed.
Sunotur SC sport derailuers.

zonatandem

Rode a Kuwa-tandem back in the 80s for a test ride.
Was white with a splash of rainbow colors. Have also seen a black one once upon a time.
Your paint job is a bit more unique.
They never were very popular, but Kuwa is/was a reliable company that just did not know how to market a tandem properly (like Fuji and the Schwinn Duosport tandems).
Pedal on!
Rudy and Kay/zonatandem

john wood

we have had or Kuwahara tandem for three years now.I'm not sure of the age ,mid-80's i guess.We love it,it had been upgraded to sora sti shifters and deore lx rear derailleur.We've put over six thousand miles on it so far,and still happy with it.

aprieto28

Woody. I would love to know what upgrades are available for this bike. I'm new to tandems don't want to spent 6K + for a new one. But, would like to upgrade wheels and shifting if possible. Any suggestions?

john wood

If your happy with what you have,I wouldn't spend a lot to upgrade.I bought mine from the owner of the bike shop I go to,it was his personal bike so the upgrades that were done were done by him,so cost wasn't much of a factor to him.As far as the drive train,we have not had any trouble to speak of I know you can get Sora parts cheaply and they seem to have been trouble free so far.Hope this has been helpful.

aprieto28

I got 18 apeeds, but the rear freewheel has only 6 cogs. My big chain ring seems to have 2 big rings and a smaller one. I havn;t tanken the time to actually count the teeth yet, but seems like 54, 50, 30 ish. Make any sense?

Paul J

Great bike, nothing wrong with bar-end shifters which are relatively inexpensive and could be upgraded to 8 or 9 speed. I'd think you could make the switch to high quality 9 speed by changing the crank, rear wheel, shifters, rear derailure and cog set which would probably be about $500 dollars. Going with Brifters would be a little more and lesser quality on the brifters.

WheelsNT

The 27" wheels are a complicating factor -- need to re-lace the existing rim or source a new 27" rim. Peter White's web page used to say he had some Velocity rims in 27" with 48-hole drilling, but it doesn't seem to say that any more -- https://www.peterwhitecycles.com/Tandemparts.asp

aprieto28

Thanks everyone. your posts are awsome. I'm learing alot. Pls keep posting. newbie to tandems.

Rambetter

Here is my opinion regarding the wheels.

I own an '87 tandem that also has Ukai 27 inch rims. Mine are hard anodized and 48 spoke, and the spokes on my wheels are quite thick.

My opinion on swapping your wheels: if they are not broken and don't need replacing, I'd keep them the way they are. While it is possible to find new 27 inch rims (Velocity Dyad 27 inch w/ 48 hole come to mind - and I've seen them being sold in several different locations just in this past year), I find that the square section Ukai rims ride very nicely.

Switching to 700c wheels might be a huge complicating factor, for example the change in leverage from the [readjusted] cantilever brakes might not be a good thing.

As far as finding tires for 27 inch rims, they can still be bought. Continental makes Gatorskin tires in that size. My favorite 27 tires that I've ridden are Panasonic Panaracer Tour Guard (or something like that). They have a lighter color sidewall (look rather "retro") and seem to provide a very smooth and comfortable ride. Plus they are folding tires (no wire bead) and are not very heavy, yet have a lot of rubber on the riding surface and seem to be invulnerable to getting flat tires.

I have actually learned to enjoy my '87 tandem with 27 inch rims a great deal. I _have_ put in lots of work and money (probably easily exceeding 1000 dollars in parts after the original purchase about a year ago) into areas that I saw fit, but the rims were not one of those areas. (Actually I did acquire a spare pair of used Ukai rims that are currently sitting in the closet.) I have a feeling that you will learn to like your new "treasure" just the way it is, or mostly just the way it is. I see my '87 "treasure" as something to show off whilst riding up and down the coast, and not so much as a serious time trial machine (even though the bike is very capable of being quite fast).

By the way I am quite fond of the color of your new bike.

WPH

The main advantage of more cogs on the back is the steps between gears are less, assuming you keep a similar range (eg 12-32T). Smaller steps make for better gear changes when cruising on flat and flatish roads. A lesser advantage is that more cogs generally means smoother gear changes because the cogs themselves are likely to be of a more modern design and have ramps and cutouts to improve chain travel.

Assuming your rear hub is a screw-on freewheel, you can get Sunrace and even genuine Suntour freewheels easily online and you could go to 7sp on the back with no other changes to your drivetrain, total cost might be <$40. Sheldon Brown has information on your upgrade options - it's probable you could go to 8sp on the back without changing the hub or having to spread the rear triangle. There are some advantages to going to a hyperglide style cassette hub (more common, slightly stronger because bearings wider apart, perhaps lighter), but the Sansin hubs are excellent and spares are available. Unlikely you would even need a new rear mech if you went to 7 or 8sp.

Wise to renew the drive chain as well: I buy 8sp chains for my sync chain for <$10 online!

No need to change cranks, chainrings etc unless you go to 9sp or more, even then you would only require narrower chainrings. Front shifting performance won't be as good as you can get with modern pinned and ramped 9 or 10sp chainrings, but it won't be terrible either. I would say those are quite big chainrings for a tandem - most here would want a smaller middle ring (39 or maybe 42T) and a smaller inner ring (26 or 28T), depending on your terrain and whether you plan on doing any touring or lugging a child on the back: Mrs WPH and I would really struggle with the chainrings you have on your Kuwahara.

If your bar-end shifters are friction only, no need to change. Sora and Tiagra brifters are good but it can be hard to find left hand shifters that will work with a triple crank.

Looking at your nice pictures, of what really is a lovely bike, I would go first to the ergonomics - seats and bars. The older style drop bars are very deep. Some stokers like suspension seatposts and the good ones (eg Thudbuster) are not cheap. Getting the fit right for captain and stoker is important - changing stems in and out is often necessary. We replaced the quill stem on our Trek for a threadless adaptor so we can access a wider range of captain's stems and also use front-loading stems which make tranpsort of the bike a lot easier.

Someone else here has already outlined your 27in tire options, they are all probably better than changing to 700c.

Overall, I suggest you exercise caution in terms of upgrading - you could spend a lot of money on this machine which could be put towards a more modern tandem if you and your stoker find you love it. Kuwahara was a very very good manufacturer - check the vintage and classic forum here on BF to see how valuable their equipment remains. But tandem (and bike) frame design and manufacturing has moved on a lot since the late 1980s and regardless of how much you spend on components you will still have to contend with the limitations of a 25 year old frame.

Always a thrill to learn about someone starting out in this great sport. Enjoy and keep us informed!

WheelsNT

Ok, I'll take a stab at this....

Let me preface by saying I have a bunch of older bikes and I appreciate them very much. However, there are a whole bunch of factors here that you may want to consider. You have a bike with a 6-speed freewheel and 27" rims, with Suntour derailers and Suntour shifters, and the chainrings are half-step + granny (see https://sheldonbrown.com/gear-theory.html#halfstep for details). This means that for a meaningful upgrade, you will have to replace the entire drivetrain and the wheels. By the time you do that, you should have just bought a different used tandem that had what you wanted in the first place. That used-but-newer tandem will already have all the stuff you would be upgrading to, but will cost far less than what you will spend on your current bike. Let me go though it piece by piece:

27" wheels -- it's possible to change to 700c, but you will spend a ton of time finagling with the brakes, either having the cantilever posts moved on the frame ($$$, plus repaint) or ending up with a sub-optimal braking geometry -- and something you never want to be weak on a tandem is the brakes. So, reasonably, that frame is always going to be 27". So right there, you've just limited your rim and tire slection to 2% of what is available in the 700c market, and maybe at a cost premium. And there won't be any high performance options available at all.

Freewheel -- there's a reason the world went to freehubs with cassettes instead of freewheels, and that reason is bending and breaking rear axles on freewheel hubs. Nowhere is this more important than on a tandem. Unless you guys are real light and ride on really smooth roads, the axle is a serious failure point.

6-speed Suntour -- the speeds are set by the freewheel and the shifter, and the geometry of the rear derailer sets the cable pull. To change to more speeds, you need to replace the rear derailer as well as the shifter and freewheel, because the Suntour derailer you have needs a differernt cable pull than the Shimano shifter you will buy. Going to more than 7 speeds will require a new rear hub, or at least a re-space and re-dish of the rear wheel, and also a cold-set of the rear spacing on the frame. If you want to upgrade the front shifting as well, you probably have to change the crankset because the chainring spacing won't be right. Shimano will tell you you have to have 10-speed cranks to run 10-speed chain, front derailer, etc., but that's not really true, you can get away with 9 speed and maybe even 8. But 6-speed is just too far away from the modern spacing to run 9 or 10 on it. I could go on but I'll stop there...

Ok, so this may sound like I'm down on your bike. Not at all! Just let's not spend a huge pile of money trying to make it into something it's not. You guys are just getting into riding a tandem, you should use this bike to figure out if this is something you really enjoy and are going to do. If it were my bike and I felt like I really had to upgrade it, here's what I'd do --

Find some Shimano 3x7 brifters and a shimano rear derailer on ebay, and swap your freewheel to a new shimano 7-speed freewheel with hyperglide. Put on a new KMC 7-speed drive chain. If you can live with the front shifting, leave it alone. If not, before you think about the front derailer, replace the outer two chainrings with something in the 53/52, 42/38 range that are pinned and ramped -- whatever you can find cheap, and the less speeds the better. If the tires are old, replace them with some 27" Gatorskins -- tires are a bigger deal than on a single, you need to keep them in good shape. You don't want to have an old tire come apart on you as a new tandem team.

This all minimizes the stuff to be swapped and the cost of that stuff, and spends the money in the important places. Brifters are a great benefit to a new tandem captain so you can keep your hands on the bars even while the stoker is moving around. Hyperglide helps with shifts under load, which you are going to do on a tandem because the stoker won't back off during shifts like you do on your single. And, you're going to do more rear shifting than you ever did before to keep the cadence where the stoker can handle it.

Then, just ride it for a while. You will probably have to change saddles, bar angles, bar tape, etc for a while until you get everybody comfortable. But other than that, just ride it for a while. After a while, you might want something better. At that point, look around for something used with at least 8 speeds, 145 OLD spacing at the rear, and a threadless headset -- a bike with those things will be able to take modern components in any area you want to upgrade.

Hope this helps! I look forward to hearing how it works out for you.

EDIT: WPH posted while I was typing, and he has a slightly different take -- but the similarity is to not try to take that bike all the way to modern. Do some minimal upgrades for minimum money and stop there.

Rambetter

While there is perhaps some truth to the statement above, I would like to point out my experience with an old frame.

I don't think that an old frame necessarily has limitations or design flaws. For example, an '87 fillet brazed steel frame that I own is, in some seemingly magical way, more pleasurable to ride than my other bike, a modern 2008 aluminum Trek T2000.

WPH

Rambetter, I hear that! I have older machines too, which I really enjoy and cherish and refuse to part with (in the face of hints gentle and otherwise from Mrs WPH). I like to ride them, look at them, own them and work on them. On the other hand my Scott CR1 SL with all the top kit is boring to own because there's very little apart from routine maintenance to work on. It weighs 7.3kg ready to race, is stiff and quite comfortable for any ride <150km, and I respect it but don't love it like my Thorn Club Tour in 531.

I agree older frames (and components for that matter) don't necessarily have design flaws or limitations. But... a 1980s cro-mo tandem frame is gonna weigh 0.5kg + more than a modern steel frame and lots more than alu or carbon, have a threaded 1 inch fork, 140mm (perhaps 135mm) rear OLD, 27in wheels and probably a shorter stoker cockpit than contemporary gear. Our Trek T200 (steel) is noticeably flexier than our Fuji Absolute Le 2.0 (cheap alu) and this can be important to tandem teams too. The question is whether it's worth spending much money on upgrades - it may be (Kuwahara, after all), but it will pay the OP to be cautious.

WheelsNT's Sora 3x7 suggestion seems sensible to me. Might even be able to find pink Hudz to match the paintwork...


Cheers


WPH

ironhanglider

I'm also in the camp of not spending much on it, unless the point of doing so is because you simply like tinkering.

I also have an old steel tandem, which came with 126mm rear spacing and a freewheel (with a bent axle). I built some wheels for it with some hubs I already had (130mm, 32 spoke, cassette) I built these up with deep section (45mm) aluminium rims (heavy but strong) which allowed me to put on an old MTB derailler, a 9spd MTB cassette, and some 9spd brifters that I also already had. However I only use the right one for gears since they are only a double and the bike is a triple, so I use a friction down-tube shifter for the front. I bought a new front derailler though which works with the old chainrings pretty well despite the lack of ramps/pins etc. I've got some Microshift 3x9 brifters to put on it as the next upgrade though. I am seriously considering getting an old 7spd cassette hub or just the freehub body and bringing the spacing back to match the original. The frame design is similar to yours, and takes a bit of effort to spring apart to put the wider wheel in. This would mean sacrificing one of the cogs though and running only 8 cogs of a 9spd cassette.

If you are going to brifters, 8spd (except for Dura-Ace) are the same as 7spd just with an extra click. This might extend the options a bit further, e.g. Microshift make 3x8 spd brifters. https://www.microshift.com.tw/road_r8.html

I'll also add that freewheels on a tandem are particularly difficult to remove because the action of two riders winding them on makes them really tight even if there is no corrosion or galling to make it worse. If it is the old winner pro cluster, the tools are not common any more. You may have to resort to disassembling the freewheel and clamping the body itself in a vice to get it off. Otherwise it is well worth taking to an LBS with a six-pack to ease the process along. Definitely use grease or anti-sieze on the threads when installing a new freewheel.

Have fun,

Cheers,

Cameron

aprieto28

Thanks to all for your knowedgable imput. I seem to go throught this modernizing phase with every older bike I buy. In the end I always leave as is unless it's broken or a safety issue. I left my Univega alone. It's comletely original with owners manuel and bought a new road bike, steel of course with all the modern gagets. My wife can only ride on weekends due to her work schedule. I hope she gets into it. may need to find another stoker, with her permission of course.

SJX426 

I agree with those above and your experinece. Minimize the change to lower cost or for comfort. I would examine the freewheel and consider going with a 7 speed, as WPH suggested. At least you get one more gear choice or improve shifting if not for the ramped teeth. I did this on my 83 Colnago without any other change and it was worth it.

Rambetter

Speaking of freewheels, in particular 6 speed versus 7 speed, I can perhaps offer some light on this subject as well.

If you are going to stay with the freewheel design (and not upgrade the hub itself to one with a freehub, or more modern, design), then from what I've heard, the Dura Ace 7400 freewheels are the most robust (as in, the strongest especially for tandem use). In fact the '87 tandem that I own originally came with a Suntour 6 speed freewheel of some sort, and the original owner replaced it with a Dura Ace 7400 7 speed.

One interesting thing about the Dura Ace 7 speed freewheel - it's compatible with Shimano 7 speed index shifters (e.g. Shimano Ultegra or bar end shifters, the clicky kind), assuming the derailleur is a standard Shimano derailleur. This is because the cog spacing on the Dura Ace 7 speed freewheel is 5 mm. For example, an Ultegra 6700 10 speed long cage rear derailleur + Shimano 7 speed bar end index shifters + the Dura Ace 7400 freewheel will work well together. The difficult part is finding the 7400 freewheel and the 7 speed index shifters (especially the bar end kind). I have seen 7 speed bar end index shifters (Shimano) sold on eBay for about 100 dollars. I also have a spare 7400 freeewheel, but it has a very wide gear range (not close ratio cluster) which is perhaps better suited to be paired with a mountain bike rear derailleur (e.g. Shimano Deore, one of which I also happen to have in the closet).

If you want more information about compatibility with gearing systems, you should perhaps read some of Sheldon Brown's web literature.

aprieto28

I confirmed that my largest chain ring was 54t. The 2nd chain ring isn't much smaller. There's a large gap between the 2nd chain ring and the small chain ring. I know I will have difficulty on hilly roads. Any Idea what the BCD might be on these chain rings and where to get smaller ones?

Rambetter

A close up photo of your stoker crank would be of help to answer your question.

JanMM

Chainring info from Sheldon Brown, including how to measure to determine Bolt Circle Diameter (BCD) so that you will know what size(s) you need.
https://sheldonbrown.com/gloss_bo-z.html

aprieto28

My cranks. I put on my glasses and was able to see that my small chain ring is 34t.

JanMM

That is indeed a large middle ring. Wonder if that is half-step gearing?
All three of your rings share the same bolts. Looks as if you have the option to use a significantly smaller inner ring, if those are threaded attachment points that I see in the picture. You would need shorter chainring bolts if the inner ring were by itself and the middle and outer rings shared bolts. And new bolts/screws for the inner ring.
Note that chainrings are available by BCD size and by number of teeth. An example of one online sites selection: https://www.bikeman.com/Chainring.html
Guessing that your Sugino crankset uses 110 BCD rings and 74 for the inner.

aprieto28

What's half-step gearing?. I also checked my freewheel. The largest cog is 32t.