devinfan

Thanks gugie! I'm a ways off actually riding the unicorn, wheels need to be trued and it needs all new cables. I also want to make sure the tires are properly glued on.

devinfan

Thanks Golden Boy, so am I! I'm going to need a bracket for the flashlight mount on the fork and a vintage Japanese flashlight, but hey - Christmas is coming!

Lascauxcaveman 

That thing's off the charts. So much strange going on there that unicorn is a much better descriptor than grail, in that you wouldn't actually expect such a thing to exist.

mikemowbz

I wouldn't even have known what I was looking at were something like this to pop up in my local listings...truly a rare, mythic beast!

You're not kidding about the quality of workmanship, as images attest.

Right time of year to have a bit of time ahead of you to get those cables, wheels, and tires maintained before that sunny-day inaugural unicorn ride.

What a find!

Drillium Dude 

What a trippy bike - so many neat/strange details. Like that brake lever with the teeth, the funky shift lever - and a serial number badge, even!

I'm hoping for more info/pics soon. Nice score!

DD

rhm

This is normal for many of the early non-parallelogram derailleurs. The spring pushes the cage to the left (big cogs), the cable pulls it back. On the disraeli gears site this is called "normal low logic" or something like that. Simplex Tour de France, and many other huret and Cyclo mechs worked this way.

This type of derailleur has two main problems. First, it is difficult to remove the rear wheel and difficult to put it back. Second, if the bike falls over on the right side, the derailleur cannot deflect the way a parallelogram can, so it ends up supporting the weight of the bike. It usually gets bent in the process, often without the rider realizing this has happened. If this is the case, the rider is at a great risk of shifting the derailleur into the spokes, much to its detriment.

Face it: bikes do fall over now and then. This is, I believe, the main reason this type of derailleur is rarely seen nowadays.

devinfan

It is off the charts. So much so that it doesn't have any of the factors I'm usually looking for, like Campagnolo gears, recognizable tubing etc. but it's my favourite bike yet. I'll probably only ride it a few times a year on special occasions like my birthday, b it doesn't matter. It looks pretty happy in my living room and I think it's earned a semi-retirement by surviving this long unscathed.

devinfan

Thanks DD, I'll try to get some better outdoor pics when I get a chance. Sorry it features neither orange, nor drillium!

devinfan

Thanks! The seller is awesome and actually passed on the contact information for the original owner. I'm trying to gather as much info on the bike as possible for posterity's sake, such as the exact year and original colour.

devinfan

Well it's new to me! I couldn't figure out what was going on. I can't really figure out the rear derailleur either, with its stacks of coins and tiny mini chain. When I'm looking at it it feels like I'm seeing an unfamiliar insect that's about to do something weird. Thanks for the tip about not dropping the bike! Would you know why there is a fixed cog on one side of the wheel?

rhm

Flip-flop hubs were pretty common. Some were threaded for fixed cogs on both sides, others fixed on one side and free on the other. (I don't know why any hubs were made for freewheel only; you can safely mount a freewheel on either type.)

My guess is they used this type of hub because it was popular. You may in fact find that the hub is threaded for fixed gear on both sides. At any rate, this gave the rider the option of setting the bike up as a fixie, for which purpose he'd have to remove the derailleur and shorten the chain considerably. Whether anyone ever did this with your bike, or even considered it, who knows.

John E

A sudden slip of the shift lever or snap of the shift cable can throw the cage into the spokes or the chain into the gap between the low gear cog and the spokes. This is why I call low-normal a "suicide" rear derailleur.

John E

That is totally cool!

The gearing looks like approximately 50-47 / 14-16-18-20-23 (which I used on my Nishiki on flat rides), so why would a long cage rear derailleur be needed?

kroozer 

I would be riding that bike regularly! I believe that is the first pre-1970 Japanese bike I have ever seen, and also the most interesting.

rhm

No, though this is a common misconception.

In fact, what you describe results only if the derailleur arm is bent (as is often the case, as I described), or if it's the wrong derailleur for the freewheel. For example, if you use a 5 speed derailleur on a 4 speed freewheel, this will happen unless you add spacers in the axle to make sure it doesn't.

When setting up this type of derailleur, make sure the derailleur cage is perfectly aligned with the biggest cog when there is no cable attached. If it isn't, you have to bend the arm, or add spacers to the axle, or otherwise do something to move the whole derailleur to the right.

The best thing to do is to bend the arm, but to do that you have to completely disassemble the derailleur.

devinfan

So... it has a suicide front derailleur AND a suicide rear derailleur?!?! Maybe this bike had a darker purpose than I imagined! The gearing, as with many things on this bike, is a mystery to me. Can't find any markings on the freewheel. I'm going to be changing all of the cables, but am thinking I won't be shifting this bike when I take it for its inaugural ride (or thereafter for that matter), I normally ride SS or fixed anyway so it's no issue. Sadly one of the awesome Wober Renforce tubular tires is bulging at the sidewall. I'm thinking for safety's sake I had better replace both of them but am hesitant to do so because I'd rather change as little as possible on the bike. Is there any way to REPAIR a bulging sidewall on a tubular?! I'm guessing not but it's worth asking.

devinfan

rhm you seem to know deeply what you are talking about when it comes to this type of derailleur. I am way out in the ocean out of my depth, which is why at the moment there is a lot of staring and no wrenching going on. Maybe after I change the cable if you wouldn't mind I can post some pictures of the derailleur in different positions and you can let me know if all is well.

devinfan

Thanks so much kroozer. I would love to ride it but am worried about wearing out/messing up/otherwise spoiling the components. I guess I could box the original components and ride it with a different set-up but I'd be scared to even take them off.

rhm

I'll be happy to look, but trust me, these things are not rocket science. And they work well; read this article if you want someone else's opinion.

I don't know the specifics of the Sanko, but it appears well made and I doubt you'll have any trouble. If in doubt, put the bike in the stand, remove the cable, and turn the wheel backwards. If the chain stays on the big cog with the wheel turning backwards, try backpedaling. If it stays on backpedaling, try pedaling forward. If it still goes smoothly, put the cable back on and see how it shifts. Pretty well, I'd imagine!

devinfan

Awesome. This seems like a clear course of action and is exactly what I will do. First step will be removing the old cable. It looks too thick to be a shifter cable to me, more like a brake cable. The cable end seems to have snapped off, leaving the cable stuck in the lever. I'm hoping it will pull right out but secretly know that it won't which is why I haven't attempted it yet.


Also, both the brakes and levers are marked Dia. Not Dia-Compe, just Dia. Initially I assumed that Dia was the predecessor of Dia-Compe, but can't find any info at all on the matter:

rhm

On the brake, on the right arm, is that a JIS symbol? I wonder if you'll find the number 5583 on the brake (or the lever) anywhere. That's the Dia-Compe JIS number. Not sure what that means, exactly, but if it has 5583, it's the same company.

On the shifter, I've never seen this before, but it looks like the cable doesn't have a soldered end; it looks like you loosen that nut, and the cable will come right off. Or am I seeing that wrong?

devinfan

Just looked, no numbers anywhere but yes it's a JIS symbol. Man, I think you're exactly right about there being no soldered end. What else would that nut be for? This means, I hope, that it's supposed to be that way. Sweet news. Not touching it! Lao Tzu is right as usual and sometimes it's what you don't do that matters, I almost messed it up!

rhm

For what it's worth, I used to have a forged aluminum 'spearpoint' style stem that was marked only 'Compe' and 'Japan.' Looked to be from the 60's. It came to me on a 1963 bike though it was not original to that bike. Anyway, this leads me to speculate that Dia and Compe may have been different companies that merged.

devinfan

Well that makes sense. Still waiting to hear back from the original owner, but I believe this bike is a '62. Velo-base says that Dia-Compe combined its technology with Wienmann Swiss to manufacture brakes in 1963 so maybe that's when it amalgamated? Wild guesswork here.

rhm

In support of that idea, your brakes are pretty clearly MAFAC inspired, rather than Weinmann. So, plausibly before the association with Weinmann. Bear in mind that a bike made in 1962 would necessarily use parts made earlier. How much earlier, who knows.