Friday News And Views

Sour Bikes Pasta Party 32"er (Image courtesy of Sour Bikes)

The 32" Watch: Sour Bikes, TPU Tube News:

The hype and number of bikes surrounding the 32" wheel continues to grow. This week Sour Bikes, a German based company, released news concerning their Pasta Party 32"er. This is a production frame which you can order now. 

Interesting bits on the bike shown on Sour's site include a Manitou fork modified for 32" wheels having a claimed 120mm of travel, Schwalbe Rick Race XC tires, and Reynolds aluminum rims in 32" size. 

Sour claims this bike has only marginally longer chain stays and stack height over the similar Pasta Party 29"er model. They used a very short tapered head tube and a curved seat tube to achieve this result. I think it is very reminiscent of Gary Fisher's early 29"er prototype which also sported a modified Manitou suspension fork, a very short head tube, and a curved seat tube.

Also, a press release was sent out by Tubolito saying they are going to offer TPU tubes for 32" wheels. Tubolito is a German based concern as well. It would seem the Germans are really pushing 32" wheels then as all the companies represented in today's 32" Watch are German based companies. 

Image courtesy of Teravail.

Teravail Launches Component Range:

Teravail is getting into the components game with a range of handle bars in carbon and aluminum, stems in aluminum, and seat posts, including a dropper post. 

News released on Tuesday of this week revealed a few flared drop bars of interest to gravel riders, some MTB flat bars, and  they also dropped news on some grips and handlebar tape as well. 

Comments: The QBP owned brand seems to have a bit of redundancy now considering QBP's Whisky Parts Co. also has similar products. The drop bars look fine, and carbon is good for gravel, so I suspect the products will be good performers. But why double up on product offerings with two different brand names? Curious move.... 

Image courtesy of Castelli

Castelli Announces Unlimited Pro 2 Jersey:

Gravel racing is pushing apparel design into new territory. This Castelli jersey is evidence of a new trend in gravel racing jersey design which combines the function of a jersey with that of a basic hydration pack. 

The jersey is designed for hot weather. Castelli recommends this piece for anything from 64°F - 95°F temperatures. The jersey has a close fitting, race cut. The design features shoulder fabric treatment which is intended to enhance aerodynamic efficiency. The pocket on the upper back of the jersey will hold a 1.5L bladder, (not included) and there is fabric loop to hold the drink hose down across the shoulder and upper chest area. 

The jersey is available in three colors. Paprika, (shown), Elmwood, (a tan hue), or black. Price ius set at $230.00 USD. You can view more details and images of the Unlimited Pro 2 Jersey HERE. 

There is also a matching bib short called the Pro Aero Race S Kit which you can check out HERE. 

Comments: I was offered a chance to test this jersey but since I am built like a linebacker and not a Pro level cyclist I declined the offer. Sizing runs small, by the way. What is shown as 3XL comes out to an American XL, and I'm being generous there, I think.  Suffice it to say that this is a serious bit of kit for anyone who wants to glean every marginal gain they can in competition at unpaved events. 

The price is a bit dear, but if you are attacking the pointy end of the gravel racing scene, you probably already are caught up in the "arms race" and a 230.00 dollar jersey for race day is maybe no big deal. I have it on good authority that Castelli gear is well made and does the job it is intended for well enough that the price seems justified. I'll leave it at that. 

Berd spoke (Image courtesy of Berd)

Berd Offers Light XC MTB Wheels:

Berd Spokes now offers complete wheels for XC racing which tip the scales at barely over 1000 grams. Featuring a carbon, hookless deign for a rim, and Berd branded hubs, these wheels should be some of the lightest wheels out there for XC MTB.

The inner rim width is listed at 30mm, so these are legit MTB racing width rims. The rims are backed by a Lifetime warranty as well. The Berd wheels are dubbed the Hawk30 Gold. A set of the Hawk30 Gold wheels runs $2,395.00 USD and can be purchased direct from Berd HERE. 

Comments: The Berd spokes are picking up steam with racing teams and people looking for the best, lightest, and most comfortable riding spokes. I've been using a set of wheels since 2020 with Berd Spokes and they have been solid wheels with no issues for me. I would imagine these Hawk30 Golds would be fantastic riding wheels, if mine are anything to go by. 

Guitar Ted Podcast Episode #97:

Another podcast dropped this week since N.Y. Roll has made it back from Mexico where he had a little vacation time. 

On this episode we discuss a wide variety of topics beginning with series events and why we like them and don't like them. We also get into the news which came out yesterday concerning those new Conti racing tires and the new Singular Albatross 32"er.  

We also discuss how some event directors are bowing out now who had been producing events for several years. We discuss this within the context of the Raputitsa event, because it has been garnering a lot of attention on Facebook with their recent posts, but this is just a high profile example from what I have noted as being a small exodus of event directors from the gravel scene of late.  

If you'd like to listen to this latest episode, please click THIS LINK to go to the Spotify home page, or find the Guitar Ted Podcast on your favorite podcast platform. Pleas like, subscribe, and leave a review. It sure helps us out on our end if you do. Thanks!

That's a wrap on this week. Get out and ride those bicycles!
 

Gravel Grinder News: Singular Cycles Albatross 32"er

Image courtesy of Singular Cycles

Singular Cycles Albatross 32" Wheeled Bicycle Announced:

Well, as many of the regular readers of Guitar Ted Productions know, Singular Cycles has been teasing a 32"er for several months now. Today the company head, Sam Alison, makes it officilly "official" and you can pre-order this titanium bicycle as a "rolling chassis". 

Sam Alison has been designing bicycles, mostly around 29" wheels, since the mid-2000's and he understands the unique challenges of getting a bicycle to look great with big wheels and not like some adolescent teenager with disproportionate body parts, as some early 29"er designs looked. The classically inspired Singular range is enhanced then by the new Albatross, despite the distinct possibility for an ungainly looking end result due to the large hoops. 

Utilizing the light, strong tubes of 3Al - 2.5V titanium in butted profiles, the Albatross has been designed for riders from 5'10" and taller. Any shorter than this and the design would suffer and performance, along with looks, would be compromised. So, the Albatross is only offered in L, XL, and XXL sizes. 

Size Large geo chart (Click to enlarge)

In an effort to ease the burden of sourcing 32" specific parts, the Albatross is offered in a "rolling chassis" format, but Singular does also offer each Albatross customer the option of choosing complete build packages. 

The rolling chassis package consists of the following:

•  Albatross frame in 3Al 2.5V seamless Titanium - butted main tubes
• Full carbon Columbus fork
• Hope (White Industries in US) Headset
• A hand-built 32 inch wheel set with a carbon rim upgrade option
• Maxxis Aspen 32x2.4” tires fitted and ready to roll

Size chart for XXL (Click to enlarge)

The pre-orders are now open and there will be a limited run made, and this will be all for now. Price is set at £3450 or $3900. Complete build packages will cost an additional amount. 

See the Product page for the Albatross and find out more behind this model's development and purpose from Sam Alison himself by clicking THIS LINK.

Thanks to Sam Alison/Singular Cycles for the images and information used in this report.  

Gravel Grinder News: Continental Announces New Terra Competition Tires

Continental Terra Competition (Image courtesy of Continental Tires)

Continental Tires has just announced an addition to the Terra line of tires for pavement to off-road riding. The newest tire in this range is the Terra Competition tire. 

Designed for riders wanting to go from pavement to gravel and light off-road rides, the Terra Competition features a new tread design which enhances performance in terms of speed and aerodynamic efficiency. 

The Terra Competition will be offered in Race or Trail casings with the highly regarded Black Chili rubber compound. 

Engineers at Continental have worked to make the Terra Competition Continental's fastest tire in the gravel category. The tread design is optimized for rough tarmac, compressed road surfaces, smooth dirt, and works best in dry to moist conditions. 

Image courtesy of Continental Tires

From the press release:

Alexander Haenke, MTB and Gravel Product Manager, Continental Tires, said: “We set out to create the Terra Competition for riders who don’t want to choose between road speed and off-road capability. As more riders mix surfaces and push performance, the demand for a fast, yet versatile tire continues to grow. Terra Competition delivers that balance, combining efficiency on tarmac with the confidence needed when the route turns to gravel.” 

The Terra Competition specs:

Race Casing: Rapid Compound, textile breaker layer for puncture protection, Black Chili compound, tubeless ready, safe for hookless rims.  

Trail Casing: Grip Compound, Robust, one-ply construction, textile breaker layer for puncture protection, Black Chili Compound, tubeless ready, safe for hookless rims. 

The first gravel tire optimized for aerodynamic efficiency. The Terra Competition in its 700c X 35mm size in the Race casing can save up to 68gms with the 35mm tire weighing a claimed 345 grams each. The 700 X 35mm Race version also shows a 17% reduction in rolling resistance over the same size Terra Speed tire, according to Continental. 

• Optimized tread design for reduced drag and increased efficiency across all-road applications
• Weight: 345g (35mm width, 28"), 420g (40mm width, 28"), 470g (45mm width, 28")
• Available in 700 x 35mm, 40mm, and 45mm and in Race and Trail casings
• Pricing:  68.95€ / £59.30 / $76.26

Available now through authorized Continental Tire dealers.  

 Thanks to Continental Tire for the information and images provided for this report.

Review: Ergon Sr Allroad Pro Saddle & BT Orthocell Road Tape

 Note: Ergon sent the SR Allroad saddle and the BT OrthoCell Road handle bar tape to Guitar Ted Productions at no cost for test and review. Ergon has not paid for, nor bribed Guitar Ted for these reviews. All opinions and images, unless noted, belong to Guitar Ted/Guitar Ted Productions.

Welcome to a new season of reviews on Guitar Ted Productions. I'm kicking things off this season with two items from Ergon. They are sponsors of a new cycling team called Canyon/DT Swiss Alt-Terrain. (Reported on HERE in a recent Friday News & Views post)

I am going to be taking a look at a couple of items the team is going to be using throughout 2026. I have an SR Allroad Pro saddle and the BT OrthoCell Road handlebar tape.  (NOTE: The link for the handlebar tape takes you to the Gravel version which is 3mm thick. The tape on review here is not on the site currently)

The reviews will eventually split off but for this introduction I'll be speaking on both products. First up we will take a quick look at the handlebar tape specs and then the saddle. I'll follow up with some comments. 

BT OrthoCell Road Handlebar Tape: The OrthoCell component of this product is really what sets this handlebar tape apart from the rest of the competition. OrthoCell is a product Ergon uses which is made by BASF in Germany. The foam padding is applied to the tape in varying thicknesses. In the case of the Road variant, it is thinner than the BT OrthoCell Gravel tape. Overall, BT OrthoCell Road is 2mm in thickness. Ergon suggests  the wrapping technique used can vary the thickness and feel of the tape according to preferences. 

This tape is 250mm long for each roll so it should cover most modern allroad/gravel handlebars and any road racing type bar.  

The OrthoCell material also figures into another handlebar accessory product Ergon makes in a pad set.  I tested those for another site and I can vouch for the OrthoCell claims. So, I have pretty high expectations for the handlebar tape. Besides, Ergon BT Allroad Gravel tape is a favorite handlebar tape of mine anyway. I just wish they offered it in more colors than they do currently. 

 Price for the BT OrthoCell Road tape is not known since I cannot find it on Ergon's site or anywhere online. This 2mm thick version of OrthoCell tape should cost approximately the same as the 3mm thick Gravel version which costs $44.95 USD. The tape should be available through Ergon eventually. 

SR Allroad Pro Saddle: This saddle has also been infused with the same OrthoCell technology using BASF's Infinergy material. A great explainer of what OrthoCell padding does can be found on Ergon's site HERE. 

The SR Allroad Pro has a microfiber cover over the OrthoCell padding which is textured in the sit bone region and smooth everywhere else. There is a large, vented pressure relief zone down the middle here which is promising relief from numbness. 

Claimed weight is 230 gm but the sample I received is 252 gm.The overall length of the saddle is 248mm and the width is 143mm for the Small/Medium seen here. There is also a Medium/Wide offered which is listed as being 151m in width.A women's variant is also offered in an Allroad Comp version which trades a carbon composite base for a Nylon base. 

The Ergon SR Allroad Pro Saddle retails for $154.95 USD. You can purchase the saddle directly from Ergon or through various online or brick and mortar retailers. 

Impressions: I have used Ergon handlebar tape and an Ergon saddle for a few years now. If you read my Top Ten Recommendos post last November you may have noticed two Ergon products made the list.

The saddle I used was the SR Allroad CORE Comp, and the shape is very similar to this new saddle I have now on test. The big difference is obviously the cut-out. But I also noted the padding is a bit more luxurious and thicker by a little on the newer saddle. 

My expectation is that I will get along with the shape of this new saddle just fine, but I do think the new one will be more comfortable. I should also note here that Ergon plainly sees the OrthoCell padding as being enough to mitigate vibrations and provide comfort because that rigid base is certainly not going to have any give! It is thick and feels like it won't have any problem keeping a firm foundation for your pedaling efforts. 

I know I've seen and heard concerns about saddle cut-outs which pierce through the saddle completely. Some feel debris coming off the rear tire could cause issues. I guess.....maybe, but this is why there are fenders. One could also simply paste a bit of duct tape underneath and cover the opening if it really became something of an issue. 

On the tape, I have used Ergon's 3mm thick Gravel tape and the OrthoCell pad kit, both things I'd be very glad to have on any drop bar bike. I saw this Road tape with a 2mm thickness and immediately wondered if it might not work well for me. However; the OrthoCell material may mitigate my concerns. We will see. I don't doubt it will be difficult to wrap though, as this has been my experience with any Ergon handlebar tape I've used to date. 

Okay, so there is an introduction to these products.; Next I have to choose a bike to put these on and get to riding. When I have installed the saddle and handlebar tape I will get a few rides in and then come back with two separate first impressions posts, one for the saddle and one for the bar tape.  

Stay tuned. This might take a few weeks due to weather concerns.  

Thanks to Ergon for providing these products to test and review.  

NOTE: Tomorrow will feature two press releases. Please make sure to scroll down the page to see both releases set to come out tomorrow morning. Thank you! 

Following Up

Image courtesy of BMC Bikes

Last week a couple of posts drew a lot of attention, commentary, and thought-provoking statements. I thought it would be good to follow up on a few things I noted in the comments and maybe put a bow on those two posts for the time being.

First, the posts. The first one I'll link to was the "Current Carbon Gravel Bike Design - What I Would Change" post. The second was the "Road Bike Trends Toward "All-Road" Territory".

Second - You folks who commented. You do know this is on the internet, right? I mean, polite, thoughtful discussions just do not happen on the internet, or so we are led to believe. Ha! So, thank you for being the good people you are. I truly appreciate the decorum and great discussion your comments brought to the posts linked here. 

Okay, so with this said, I wanted to react to a few points made in the comments which I may delve into further in a subsequent post. The first being crank length. I found it interesting that a few of you touched on the aerodynamic aspects of shorter vs longer cranks. This is something which doesn't get spoken about enough. Position on the bike being tangentially important here as well. I say this because longer cranks were used in the past with time trial bikes, so I think crank length is less important to body position on the bike for the finely tuned athlete. 

Image courtesy of SRAM

Obviously there is a dissenting opinion regarding shorter crank arms for riders which was brought up as well. Leonard Zinn, who has done a lot of research into crank length and bicycle riders has a formula which might point to longer crank arms as being bio-mechanically better for you. 

According to Zinn's formula I should be riding 181mm cranks. Ironically I have used 180mm cranks off and on for many years. Most recently on my "Ride For Jacob" last Summer. (Link to my gear review where I discuss what I thought about 180mm cranks)

Another interesting side-point was made in the road bikes becoming gravel bikes post. It had to do with perspectives of riders being different based upon their primary riding style and bike choice before transitioning over to gravel bikes. 

I find this is a valid way to think about gravel riders currently. However; this won't be so easily delineated when riders start on gravel bikes and go into adulthood/age with gravel bikes. I think this is starting now, to be honest. 

At some point, a drop bar bicycle with fatter tires won't be "gravel" or "road", it will just be an all-around bike with drop bars. This has already happened with 29"ers. Back 20 years ago you were riding a 29"er MTB or a "mountain bike" which was understood to be a 26"er, but no one said "twenty-sixer" then. Eventually 29"ers became "mountain bikes". Almost no one calls these bikes 29"ers anymore if they are under 30 years old. 

Once "gravel bikes" become just another bicycle, I think those who grew up on them will not perceive gravel bicycles as having to be "more road" or "more MTB" anymore. 

Okay, those are some initial thoughts I had after the comments on those two posts. Let me know iof you have any further thoughts as well. 
 

 

Gravel Grinder News: New Minnesota Based Event Series

Image courtesy of the grvlsota site

A new Minnesota based gravel event series has just been announced which will include 12 events over the course of 2026. These events are - for the most part - long-standing gravel events in the state. 

The series will not homogenize each event to fit a mold, and competition, while present, won't be the main focus. The series won't even charge a fee to participate. 

The focus will be to keep each event in the series independent and free to evolve its own identities. Riders can expect an experience at each event not unlike what there was previously. The series will try to enhance participation across Minnesota events, highlighting Minnesota's vast gravel and dirt road network while compiling points for a leader board. Participants who compile the most points will get some sort of season-end recognition. 

Many of the details are being ironed out yet, but you can check in at the "grvlsota" site to see what they end up doing there. 

Image courtesy of the grvlsota site

The current event calendar for the inaugural grvlsota series is as shown below:

May 16 – Spring Valley 100 – Spring Valley
May 23 – Le Grand du Nord Gravel Classic – Grand Marais  
June 6 – Kasners Kick Duchenne (KKD) – Farmington
June 27 – Woodtickr – Hawley
July 11 – Freedhem Gravel – Freedhem
July (TBD) – The Wolf Bikepacking Race – Finland  
Aug. 22 – Hero Gravel Classic – Stillwater
Aug. 30 – River Valley 100 – Mankato
Sept. 5–6 – Gray Duck Grit – Cannon Falls  
Sept. 19 – Rosewood Gramble – Thief River Falls
Sept. 26 – Heck of the North Gravel Classic – Two Harbors  
Sept. 27 – Kato Bike Fall Fest – Mankato

According to the website there will also be a podcast called the "Level Be" podcast which will highlight the events in the series, interview event directors, and cover other event news. 

The grvlsota series is an effort by the non-profit Level Be Adventures organization who aim to promote Minnesota gravel events and tell the stories behind them while tying together a community of riders. They also hope to feature what is good and enjoyable about the courses represented in the series and highlight the small towns and villages these events benefit.  

This will not be the first gravel event series in Minnesota. During the late 2000's Almanzo 100 organizer and Gravel Cycling Hall of Fame inductee, Chris Skogen, started the "Race For The Cup" series, which the Heck of the North was a part of as well. That series was short-lived, however, and happened before gravel events really took hold of the cycling consciousness.   

Breakdown: The Repair

Last week I had my crank arm come loose on me. This was on the fixed gear set up I am using on my Twin Six Standard Rando v2. You can go back and read my post about this occurrence HERE in case you missed this. 

Since those plastic pre-load bolts are scarce in my world, I had to order a new one and I got it in on Tuesday of this past week. I also somehow misplaced my Park tool "wing-nut looking" installation tool for this special bolt. So, I ordered a new tool, but this time I got a Unior tool for the install of the plastic pre-load bolt which cost a lot less than the Park Tool one. 

While I was at it I also bought two of those excellent Lezyne side-loader cages I've purchased and used before. I'll likely do a separate post on water bottle cages soon, and I'll hold off on my comments on the Lezyne cages until I post that article here. 

Ordering a plastic pre-load bolt for a Shimano crank was not as easy as I thought it could have been. I ordered from Jenson USA, and their descriptions were sorely lacking for such a part. Without my background in bicycle repair, I may have missed a choice which - as it turned out - worked for me. I can easily imagine an average rider being very disappointed in the information, or lack thereof, for such parts. 

But Jenson has a huge inventory and who cares about a part that costs a couple of bucks? Well....you cannot run a Shimano two-piece crank set without that stupid plastic bolt, so it is kind of imperative for there to be clear information for consumers. That's my take. 

Making sure the bolts are torqued properly.

Installation is pretty straightforward. I did put a thread locking compound on the plastic threads of the pre-load bolt this time, just for a little extra insurance. We will see how this goes. 

Then I torqued the pinch bolts, using an alternating tightening pattern, to 14nm. It is important to note here that HollowTech crank arms are very intolerant to loosening or tightening one bolt all at once. That is a recipe for crank failure as the uneven loading will crack the arm. It is best practice to alternate when tightening or loosening these bolts, or with other similar set ups such as stems and some other components which use pinch bolt clamping force to stay attached. 

So far, so good. I rode the bike for a good half an hour to test the parts and see if anything loosened up. Next I'll do several short rides, test everything again, and only then will I be satisfied this is good to go. 

Which brings me to another point. Testing. Shop mechanics generally do not get to test a repair, and long term, multi-situation testing? Forget about it! So, most retail bicycle mechanics have to do their repairs not only quickly, but without any real assurance the repair will hold up, in some cases. 

Obviously most mundane repairs are not part of this discussion, but there are some things which only will be proven out, or diagnosed, with time and trials. Consumers are not very tolerant of this, but the reality is that if you want a very secure and trustworthy repair, you have to pay in time and in money. 

Don't blame your mechanic if you are in a hurry, or won't pay him/her what they are worth. 

The Bottom Bracket That Was Too Good

When I built up this bike in '03 I used a UN series BB

A while back, a reader here asked a question in the comments which has inspired this post. It is about one of my favorite bicycle components of all time - the UN series of bottom brackets by Shimano. 

The Background:

First of all, it may be a good thing to consider the context of the times before Shimano created the cartridge bottom bracket. This was when all bicycles in bike shops generally had some sort of square taper spindle bottom bracket which was "fully serviceable". 

What I mean by the term "fully serviceable" is that the component could be torn apart, inspected, have parts replaced, re-lubricated, and reassembled making the potential for the component to last a long time fairly high.

Diagram showing a cup & cone serviceable bottom bracket

While there were variants on the theme, a serviceable bottom bracket was typically made up of a hardened steel spindle, loose ball bearings, also in steel, two "cups", and usually some sort of lock ring. 

In this sort of arrangement it was absolutely critical for the frame to have clean, straight threads inside the bottom bracket shell and that the faces where the bottom bracket tube faced outward on either side be 100% parallel to each other. If these things weren't true, the bottom bracket would wear prematurely, or be unusable due to poor adjustment capabilities. 

The cup and cone set up of this type of bottom bracket required skill to set correctly or the bearings would wear out, along with the cups and spindle, before they should. This adjustment required various different spanners, specific to certain types of bottom brackets. Additionally, this sort of bottom bracket was prone to contamination from wet weather riding, dust, and dirt. 

Take these things and add the dozens of variants (differing spindle lengths and thread types) and a repair shop could quite literally have a machinist's cabinet full of spares to service these bottom brackets. Not to mention the time required to install and adjust these bottom brackets.

The Cartridge Bottom Bracket: 

Along about 1992 Shimano introduced a new bottom bracket which was sealed up inside a metal tube so you could not see the bearings. They called it a "cartridge" type bottom bracket. While the first cartridge style bottom brackets looked very similar to what you can still buy today, there were a couple of weird quirks regarding the originals.  

Originally the plastic cup was on the drive side.

Oddly enough, the plastic non-driveside cup you might be familiar with on a cartridge style Shimano bottom bracket was actually on the driveside originally. Obviously these are left-hand thread and are exceedingly rare. Because the plastic wasn't quite up to the rigors of drive side pressure, Shimano quickly switched the arrangement to what is currently available today. 

Another oddity was the original cartridge style bottom brackets were serviceable. You could take the bearings out, re-grease the unit, and the cones were adjustable via a specialized tool sold by Shimano. I happen to have the tool, oddly enough! 

Additionally, the cartridges were not specific to bottom bracket shell length originally. This difference between 68mm and 73mm shells was accounted for by the shoulder in the inside diameter of the plastic cup. A wider shoulder was for 73mm shells and a narrow shoulder was for the 68mm shells. You could use a cartridge unit in either shell as long as you had the proper non-driveside cup. This reduced the number of variants Shimano had to make since every cartridge worked with both bottom bracket shell widths.

Finally, and most importantly for mechanics, the Shimano cartridge system reduced the number of bottom bracket variants by a very significant amount. There were less spindle length variants and you didn't have to worry about bearing race variations between similar width spindles either. This made stocking bottom brackets easier for shops and easier for manufacturers as well, since Shimano only offered certain spindle lengths. In fact, now you pretty much only have three spindle lengths which cover almost every application.

The original UN series was split up into three levels matching the old DX/LX/XT hierarchy for MTB and the 105/Ultegra/Dura Ace on the road side. XT, and eventually XTR, along with Dura Ace had metal non-driveside cups instead of plastic and were UN-90 series. The mid-level was UN-70 series, and the original entry level cartridges were UN-50 series. Later on lower series cartridge bottom bracket variants were offered to accommodate entry level MTB/Hybrid applications, and some road bike/touring bike applications as well. 

Image from a recent eBay listing for a UN-71 cartridge bottom bracket

Just Too Good!

As I said, these were made so well they were too good! Shimano sealed the units so well they resisted contamination to a great degree, making the units last far longer. While the UN-70 and 90 series were lighter and had better machining, the UN-50 series was so much better than previous serviceable bottom brackets, and went for such ridiculously low prices, everyone used these when they could. Of course, Shimano eventually made less expensive, lower-tier cartridge bottom brackets and those - while possessing the long-wearing traits of the upper end units - were far less quality in terms of bearings and free-movement. 

Eventually Shimano moved on to pipe spindle type bottom brackets around the year 2000. The square taper bottom brackets fell out of favor as crank sets became two-piece with spindles and bearings were housed in separate cups. This was when I started hoarding square taper UN-50 series bottom brackets. 

I've run the same UN-52 BB in this bike since it was built in '07

I ended up with several since I was a mechanic and when folks upgraded, or thought these were bad, I had first crack at owning them. I used a few on bikes I still ride today like my Karate Monkey, my OS Bikes Blackbuck, and my Pofahl Signature. 

I had to replace the one in the Karate Monkey after 4 Winters of abuse, That one was frozen in the frame! I had to remove it piecemeal. 

I maybe have had to replace one other of my used bottom brackets due to it being worn out. 

So, you perhaps can see why Shimano moved on to stiffer pipe spindle bottom brackets and different designs, but there is absolutely nothing wrong with a square taper crank and a Shimano cartridge style bottom bracket. You can purchase brand new UN-55's yet, and used UN-70 series bottom brackets are out there for right around $35.00 - $40.00 each. 

If you have any further questions about these or other components, let me know in the comments. Thanks for reading Guitar Ted Productions!