samg07094

[Complex story in this thread. Much worrying about my beloved Panasonic, together with buying a Cannondale Quick 6 and finding solutions to the Panasonic Problem. All in all I learn more about bikes than I knew before. The discussion has many URL pointers.]

Panasonic Sport Deluxe -- 64cm

The bike has been perfect for me. I owe it. I mean that seriously, at the edge of a Toaist relationship with a maroon bicycle. December 1980 manufacture by Panasonic Kyoto with Shimano parts that look to be good for 300 to 500 years use. 29 pounds of double-butted 1020 Japanese steel brazed together with massive lugs. 27x1.25 Kevlar-invested tires that handle pot holes with minimal complaint. Carries 30# of groceries in DIY low-COG buckets.

Perfect for what I need. Problem is, I got old.

At 64cm, the step-over clearance is a negative number. I'm tall... not tall enough. The bike works so well that I am willing to do the gymnastics to use it. But now I'm getting into old age and need to downsize 60cm or 58 cm.

Frame Replacement

Lord knows, what might be compatible? What can be preserved from the Panasonic ?

One fantasy is getting a Cannondale R1000 frame -- minus the carbon fork? -- and slapping everything Panasonic/Shimano on it. The steel Panasonic forks included.

I love the combo of rolling efficiency and traction of the 27" tires. The world went to 700c but these 27" wide ones seem more stable to me.

#1 priority from this project is not going down or getting hurt in an emergency dismount. We have one (1) small hill, a Rt. 95 overpass, and not much for grades here. Weight is not a consideration. (Hurricanes Irene and Sandy flooded us instead.)

Rebuilding the 64cm to a 60 cm

Turns out it's only mildly insane to consider rebuilding the frame. Time soak, yes. Right equipment, yes, but same as other pipe work. Panasonic published the geometry in detail. If this was a welded alloy modern frame, then no way. But the 1020 steel and brazed lug construction make it plausible -- a metal-bladed band saw is the only specialty tool I'll use.

There's a sequence for taking the lugged frame apart. Our local welding guys think it's a good size for a project. Pipe is 1020 so not a problem and the lugs shouldn't be hurt either.

The easy part is resetting the seat stays. They're brazed at the bottom. The welded top joints can be cut/rewelded to the lug at the top.

It's a labor of love. Plan goes to these steps:

-- Get the bike down to a bare frame. Use paint remover, then sand blast where heat will be applied
-- Remove the seat stays
-- Cut twice at the seat lug. Cut once at the bottom of the down tube.
-- Remove the short tubing segments from the three lug fittings on the seat tube. Use a small chisel.
-- Cut the top and down tubes to precise lengths and end angles
-- Recycle the lugs, first by using heat and air to remove brazing material. Refit the frame to its new size.
-- Check for fit and angular precision.
-- Rebraze.
[Discussion below tempts me to re-do the chain & seat stays for a longer tail. The globe trekker guys like the idea. Since this is a 1020 steel bike, it's a doable enhancement.]
-- Have a talk with the seat stays. Reattach. Weld top, braze bottom. That's where the tig earns its keep.
-- Decide on something for a paint job. Don't-Steal-Me Maroon has done a good job so far.
-- Reattach everything that hasn't disappeared to other projects.
-- Ride.

This seems a crazy amount of work. Crazy fer shur. Love that bike though so it's got to be worth it. Maybe somebody has a Panasonic Sport Deluxe 60cm frame in the attic ??? [Finding that 60cm frame gets to be a permanent To Do Item.]

HELP !

Ideas for my delusional frame downsize project or finding a suitable antique frame or finding a compatible modern frame will all be appreciated.

Buy a new bike. Needed to match to the No Frills integrity of the Panasonic design. (Hurray, Mr. Matsu****a!) -- which in the thread leads to much discussion of optimal alternatives. AND finally to exploiting Craig's List to steal a like-new Cannondale Quick 6 for half the cost of discount retail. Evidently the CL god wanted me to have this bike.

Thanks for the HELP !! And the frame downsize, frame mod project is up without the Harry Potter wand for sometime soon, after it gets CADed or just drawn out if and when my drafting table can be cleared off........

HillRider

Well, there really is a more modern alternative that is as stable and utilitarian as your Panasonic and doesn't require major and impractical surgery. A Touring bike. The Surly LHT and Trek 520 are the most well distributed models but there are others. Yes, they have 700c wheels but will accept tires as wide as your current 27's and there is nothing more stable about 27" rims than 700c. The radial difference is only 4 mm or about 5/32".

Basically what you propose to do to your Panasonic is wholly impractical and potentially dangerous. Either find a contemporary Panasonic frame in the correct size or bite the bullet (and not the toptube) and get something modern that fill the same need.

dsbrantjr

"This seems a crazy amount of work. Doable, maybe. Crazy fer shur."

In my business we say that you hire a consultant to look at your watch and tell you what time it is. I think that you have answered your own question already.

bikemig 

Find a vintage bike with a similar geometry to your existing bike in your size. You are trying to recreate a "feel" and this should do it. There are a lot of great older bikes out there looking for a good home and some of them can be found here if you ask around. But start with the right frame size and the kind of riding you want to do. There is nothing you can do with a bike that does not fit you no matter how many wonderful memories you have riding it.

anixi

^+1! Post the frame on the frame trading thread. Here's the link:

https://www.bikeforums.net/showthread...ss-around-game

AnkleWork

Why not sell it and buy one that's less "perfect" and more suitable?

bobotech

Time for a new bike. You can find a very nice classic bike with a full chromoly frame (no more heavy 1020 hi-ten gas pipe) for far less than you propose to spend fixing your bike up. A classic Trek 520 would fit the bill perfectly and be more flexible and lighter.

fietsbob

Asked like you are not capable of essentially building a frame from scrap, or scratch..

"1020 [thats mild steel] steel". tolerant of overheating but not worth the effort since its
just nothing special steel.. thicker wall than the stuff with higher tensile strength..

there is a frame builders section

N-1 then N+1.. now the size you need has a tangible Number.. 60 ..

learn if the next one uses a ctr to ctr or ctr to top as the size measurement ..
Ctr to top of seat tube will have the top of the top tube Less ..

samg07094

Thank you. Yes, indeed.

One problem: I don't know what's compatible. Another: despite the "rules" there you'd have to think that swap+cash is a practical approach for most riders. A 33-year old 29# Panasonic 64cm is not going to swap even for something with a more popular name or newer materials.

fietsbob

Consider a Local sale Trade in , a Bike Shop may take the Whole Bike In some trade for a new bike ,
or another Used one they may have . taken in trade..

see if Craig's list has any like yours as a Price Guide, used..
you may find something usable, to Buy, there too.

bikemig 

You can easily get $150 for your bike from CL; more if you live in a hot area. Put that money to work and buy a great vintage bike. Here's a totally cool vintage bike that may be your size (it is a 59cm) from a C and V on this site: https://www.bikeforums.net/showthread...igh-Gran-Sport
If you let people know your size, the kind of riding you do, and the amount you are willing to pay, something good will pop up via this website.

samg07094

Thanks guys. The bike's 33 years old and for what I do and with the mods and add ons and for this environment it's p-e-r-f-e-c-t. And it's a bit rough and No Name so it doesn't get stolen. (The lock is 20 years old.)

Then there's a couple of interesting/useful/wowee! ideas: "A classic Trek 520 would fit the bill perfectly and be more flexible and lighter." Or get a frame from an early Trek 520 that uses the same 27" tires. "Find a vintage bike...with a similar geometry" translates to a frame with similar geometry. (More weight, for me, means a tiny extra bonus with more exercise.)

Then there's a note to caution: "Basically what you propose to do to your Panasonic is wholly impractical and potentially dangerous."

Of course it is impractical. Everything you do for love is impractical. But dangerous, no. This is 1020 tubing and we're not doing a high pressure steam line. I bin doin weldin for 50 years, so if it takes fabricating new lugs that's fine. If I get ambitious, gusseting the angles with 12-guage won't take more than a half-hour.

Prime objective is a safe ride. Saving Mr. Matsu****a's Sport Deluxe comes second.

I'll look for a Trek 520 frame or another Sport Deluxe or Sport frame. Then there's all the time in the world to go playing pipe guy on the 64 cm. It's a grand total of seven joints to work -- a manageable task -- and if it takes fabricating a seat-angle lug then so be it.

Sound sensible ? Given the parameters.

HillRider

Give up on the idea that there is anything superior about 27" rims. There isn't. Tire and rim choices are far better in 700c wheels these days. 27" is an idea whose time is past.

Welded butt joints in tubing with thin walls are not strong enough for what you will put them through and making lugs is anything but easy or straight forward. Also, think about what you are proposing. By the time you get through cutting, splicing, welding and gusseting, the frame you will wind up with won't be even a shadow of the original Panasonic. Start with a suitable complete frame and let yours go in peace. It gave you 33 years of service. That's enough.

samg07094

Thanks, but this doesn't use welded butt joints. After I cut it down, it's still straight tubes brazed to lugs for the diamond.

Also, the term "butted 1020 steel" refers to having the middle of the tube thinner than the ends. It has to flex for vibration, so that happens at the legs instead of the angles.

You can calculate rigidity with a slide rule. Using a 6cm 12-guage gusset more than compensates for losing the 4 cm of thicker tubing at the end. If you adopt this approach and want extra rigidity, use a thicker gusset material. This 1980 Sport Deluxe is massively overbuild to begin with; it could ride a 400# cyclist.

fietsbob

Just go shopping for another bike frame. maybe a 58?

Medic Zero

What?! I have yet to meet the load an old mountain bike won't carry. Overloaded touring? Check! 280 pound rider? Check! Attach pegs to bottom of front rack and put 250 pound passenger on it regularly? CHECK! I used to regularly put three bankers boxes of documents on the rear rack of my messenger bike (another early 90's MTB). That's nearly 150 pounds. When I had that load on the rear, it usually meant I had another 48 pound bankers box on the front rack.

HillRider

Uh, nobody makes "butted 1020 steel" tubes. AISI 1020 is the mildest of plain carbon steels and in the bicycle lexicon is called "Hi-Ten" or, more likely, "gas pipe". It is used only for the cheapest of bicycle frames and no maker will ever bother butting it.

Do what you want. It's your time and money but there are certainly more efficient and better way to get a bike that will meet your needs.

TallRider

I have butted 1024 and butted 2001 steel frames in my garage. but don't think I've seen butted 1020. would it have been out of the question for a late-70s bike? but even if it exists, it's not very good.

Hear on.

samg07094

Not any more? Perhaps. More likely you are addressing the racing/enthusiast market and missing the commercial market. Butted 1020 carbon steel..... dirt cheap.... all through the 1960/1970/1980/etc these dreadnaught bikes have been turned out by the hundreds of millions for Middle Class commuters. These are not 10 kilo mid-price modern touring bikes (selling today $400 to $1,500.) They run more to 15 kilo with accessories.

As with this 1980 Osaka manufactured Panasonic, the workmanship can be quite good.

Curled bars, good brakes and a Euro setup make these much more functional than upright cruisers.

Wow !! Now that raises a temptation.

The big reason for loving this 1980 Panasonic is that the big 27" tires provide excellent traction when the bike is loaded with groceries. The load carrying rig couldn't be simpler: a Bell rack has two buckets attached on the sides. Plastic buckets, zip-ties, two feet of a broom handle, reflectors, stickers = a Bette Midler of tacky.

At least it's not an adult tricycle. We'll see about that 10 - 15 years from now.

At least I didn't come up with the idea of putting up that &^%#$%^%^ 1776-foot $2-billion target, across the river from us.

When I look at mountain bikes, I see hinged designs that have no obvious, in-store provision for carrying provisions. Please educate me.

Keep in mind that I'm older, so balancing 150# of banker's boxes on a flat platform up front is a seriously risky proposition. The low COG buckets is what I've settled on as a safe mechanism. My plastic buckets cost $12 for 4 of them at Wal-Mart. 14L x 10W x 15D. The right-side one sits just above the gear system..

The tires on the mountain bikes demand attention. Built for nothing but traction. The bikes are low COG. Gawd knows durable. I love what I've got, but old age forces adjustments to every single thing. If a mountain bike is where I need to go, that defines necessity.

I don't see how you carry groceries? How can I attach buckets? Where do I find weight limit information on these bikes? (One good one has a 225# limit which doesn't strike me as much of a safety margin.) First internet look, it seems like mountain bikes are used to ride trails, not carry groceries. Guys moving banker's boxes on Wall Street are 1-in-a-1,000,000 for bikers.

Thanks again !!

HillRider

I hoped I had put that "big 27" tires" idea to rest. You can buy 700c tires bigger, wider and with better traction than any 27" tire. As also mentioned earlier, the diameter of a 700c rim is only a tiny amount smaller than a 27" wheel. The current crop of "29er" MTB wheels, which are 700c rims that take wide tires, will take tires wider than anything you can get in 27".

You are describing full suspension mountain bikes which are certainly not what you want. Find an older "hard tail" frame and, better yet a hard tail with a rigid fork. These are super durable and will have rack mounting eyelets to let you carry whatever you want.

hamiltonian

27" tires are not special except that they fit on old bike frames that were designed for them. Even in this case, you can get long-reach brakes and put 700c wheels on these bikes, and you'll be better off because you'll have a wider selection of wheels, rims, and tires to choose from. I may be wrong, but all 27" wheels take freehubs (maybe it's just most) which offer inferior strength at the axle compared to the cassettes that come standard on modern 700c bikes. 27" tires don't give you better traction or carry groceries better than similar, same-width 700c tires. You really need to dispel these strange notions you have about 27" tires.

However, if you love 27" that much, you can find many good-quality 80's steel bikes out there that would fit you better and still have 27" wheels.

If by "hinged design" you mean a suspension system, then that's not the kind of bike you want, anyway. The MTB you'd want would be a hardtail with a rigid fork. But you don't strictly need a MTB, either. There are tons of solid modern bikes that can carry you and your groceries. Most bikes that aren't intended for racing can be equipped with a rear rack and front basket.

You can hang all kinds of things on a rear rack. Why do you think that only your bike can carry things?

I don't even understand what you're saying here, but as I mentioned already, you don't need an MTB.

What do you hang your buckets on now? Why can't you hang things on a rear rack?

I don't know anything about weight limits for bikes. I'm 310 lbs and I go grocery shopping on any of my bikes that's not a racing bike, but I ride those, too. No bike yet has ever collapsed beneath me. I've never even had a pinch flat, but I'm an old truck driver who understands bumps in the road.

I think you're just making up excuses because you really want to do your frame-rebuild project, and I say go ahead and give it a shot, but at least be honest and admit that it's for fun and not practicality. A modern bike would serve you perfectly well. I'm old, too, and I don't see any virtue in a bike that's heavier than it needs to be.

ETA: For reference, here's one of my grocery bikes, and it even has 27" wheels. It was a dumpster bike, and I put about $100 worth of parts in it, including a $12 basket and a $15 rear rack. I have cheap panniers that I hang cloth grocery bags on. Eggs and bread and such go in the basket. My point is that almost any bike can haul groceries.


nishiki-03 by eeroket, on Flickr

wrk101

Just about everything is compatible. That's the beauty of that era Japan built bike. Now the only time swapping parts will make any sense is if you have the time/tools/aptitude/pile of parts. Otherwise, cost prohibitive. In addition, while I love Panasonic bikes (and I have a pile of them), the parts on this model are usually very basic. Much better off selling it and buying a replacement used bike in the size you desire.

sreten

Hi,

I'd buy a similar era similar type bike that fits and then put all the best parts
on the bike I was keeping and then sell the other bike based on your frame.

I can't think of a more sensible approach. You'd probably still get
pretty the same amount for your bike or the swapped parts version.

You might find a bike with some better bits. Still the difference should
be relatively small, what you pay for a smaller more common bike and
what you get for a rarer large framed bike.

rgds, sreten.

Lot more choice of modern nice tyres at decent prices for
622mm rims over 630mm rims, and I mean lots, loads more.
Most brakes will handle the 4mm rim radius difference.

bobotech

The reason why we keep mentioning the Trek 520 is that the mid eighties models and up have nice long chainstays and all the rack mounting bosses you could ever desire and they will take 700c wheels with ease, even the old '84 and '85 models. The long chainstays provide nice stability when riding and prevent heelstrike on the panniers. The 520 was one of the earliest bikes that embraced touring or grocery getting easily. Its easy to put racks on them and attach whatever you want onto them. A guy at my co-op built brackets for those 5 gallon square buckets and attaches them to his early 520 racks.

So much easier than cutting up an old 1020 gas-pipe bike. Yes, Panasonics were good/great bikes but your model is rather low end and isn't really worth putting much time or money into.

And please put the 27" wheels to sleep. They are older and outdated. They will still be making tires for it but there isn't nearly the selection that there are for 700c wheels. You will be amazed at the offerings available for the 700c wheel.

A couple more notes. A rigid older mountain bike frame would be perfect for what you want. Do not bother even looking at any full suspension or even front suspension mountain bikes if you choose to go that route. Look for a classic eighties or nineties mountain bike from a reputable manufacturer such as Specialized, Trek, Giant, etc. NO huffys or roadmasters or mongoose (note, older pre 99 models aren't all that bad, its the newer ones that suck) or free spirit or other junk bike company. The other note is the mountain bike tire. It sounds like you do pavement riding only. If that is the case, then you want slick tires. Slicks either with 700c, 27", or 26". You don't need ANY tread at all. They will roll smoother and ride much nicer than any knobby or treaded tires. You cannot hydroplane in a bike ever unless you manage to get over ninety miles per hour so tread is unnecessary.

samg07094

Wow !! What a great thread. This is advice in the A+ range. Same time I've been doing CraigsList crawling, Amazon/eBay crawling, Sports Authority shopping, whatever-it-is-we-do-at-Wal-Mart, and a couple of garage sales.

Your advice translates to practical options with costs in the $100 to $500 range by the dozens. Typically:

-- K2 ZED 4.6 Mountain Bike. Hard-tail 26"x2.0 that weighs close to 20#. Aluminum Frame, Rock Shox XC28 Fork, 24 Speed, and OMG/hotbarbie DISC BRAKES. 20" seat tube geometry. Brand spanking new! At Sports Authority with a bike shop on site and extended warranty available. A 15% OFF coupon in place today for temptation.

-- Trek 820. Entry level hard-tail with similar geometry. Many show up used. Apparently not uncommon as an unmatched-for-size Christmas gift bike. $100 on Craigslist. 3 of them.

-- Trek 1000, an older model 6061t6 alloy road bike, similar to the Panasonic Sport Deluxe. Gets good reviews online. 58cm used model. 700c wheels. 1990s. Asking price of $200 on Craig's List. CL, so negotiable.

-- A used bike shop in Harlem has a number of bikes, a Trek 7.3 that looks new, asking $400. List was $689.

-- NEW BIKE recommendation: seems Raleigh owns Diamondback. They make a solid Insight STI-8 model that is available in 15/17/19/21/23 models. The 23 size has 34" standover and 25" top tube; not quite the problem of the Panasonic's 36" standover. 700cm tires. Gear shift is a Sealed Cartridge -- no derailleur! Quiet! $550/free shipping amazon.

I'm getting up to go for a ride. Down and back the Hackensack. Camera and 9x63s in the pack. It's sweet, always changing. Enjoy!

NOTE: used Trek 520s are hard to find. There is one for sale in the area: Trek 520 2013 54cm$1250 which seems a high price for a straight-weld not-lugged tourer. (Lugged construction works like gussets, so you get practically unbreakable angles.) This looks to be a thoroughly competent bicycle.

Here's another p-e-r-f-e-c-t single-speed grocery carrier. A mere 200# out of the box. What our banker's box delivery guy could have had in his dreams.... for $1311 + $130.28 shipping.



-- www.globalindustrial.com/p/safety/parking-lot/ike-bicycles-tricycles/front-loader-quadricycle-500-capacity-w-front-and-rear-platform-orange

Go shopping, what, once a month? And a 100% Made in U.S. web site for trikes:

-- worksmancycles.com/shopsite_sc/store/html/page13.html