macstuff 

I'd be interested to know what people here think of the 90s fad of bonded frame bikes.
Experiences through ownership, grapevine stuff and especially any failures people have had and heard of.
Off the top of my head the most prolific were Raleigh and Trek. We see a lot of these two at the co-op.
So far I have only heard of one failure, and that may have been due to owner error with heat, but they are pushing 30+ years old now.
Are there any current models?
Has it run it's course?
Should they all be scrapped?

Let's see your bonded frame bikes!!
Here's my Raleigh Dyna Tech SP1000. Titanium tubes to Alum lugs. It's on the way back together and should be ready for spring. As it sits, it's together as a mock up for measurements. Frame still needs a couple more decals and clear coat.

Pantah

I technically own a bonded frame bike, a late 2000's BMC (about the only manufacturer still doing carbon tubes bonded to aluminum lugs at that point), but that's not terribly old and hasn't had any issues. My brother once owned a late 80's Vitus and the only issue with that was one of the dropouts on the fork came unglued. JB Weld fixed that and lasted up until it got stolen. I'd image it's still holding up today, if it hasn't been stripped of its parts yet.

If one of those older bonded frames comes into my ownership, I personally wouldn't be afraid to ride it. I rather like them and will probably eventually have a vintage one.

blamester

I got a pretty much nos tvt 92 6 months ago. I have no fear of it. No amount of normal riding riding will break it.



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Chuckk

I like bonded frames.
Seems to me that it was an answer to how to assemble frames without skilled (brazing / welding) labor.
Miyata, Bridgestone and Panasonic all sold them (I think the Panasonics were built by Araya. and were only one year in the U.S.


1991 Miyata Elevation 5000


1990 Bridgestone Radac 2100

Retoocs

Pretty much most carbon fiber frames are bonded frames. The main triangle is made in one piece and bonded to the seatstay/chainstay. Trek still makes their frames pretty much like the 90's OCLV frames of bonding tubes to lugs. Colnago bonds carbon tubes to carbon lugs. Now there's also 3D printed titanium lugs bonded to carbon tubes.

Jeff Wills

Oh, my... the '90's are "vintage" now. I don't disagree, but it makes me wince. (OK, that was my back.)
You would do well to look at the previous generation of bonded frames, the Vituses (Vitii?) and Alans. While the bonded aluminum frames held up well, the carbon-fiber tube/aluminum lug frames had a nasty habit of coming apart at the lugs. This was usually due to galvanic corrosion and/or poor preparation of the bonded surfaces. By the '90's the production processes had been worked out. They should be bulletproof.

tgot 

Original owner of a (97ish?) Trek 2120, carbon fiber tubes bonded to Alu lugs and rear triangle.

No problems! But I ride a lot less than many here.

I do try to give it an inspection and wiggle. I worry most about corrosion from sweat. I swear a lot, sometimes use the bike inside, and my sweat is apparently very corrosive. As in, multiple digital wristwatches of various brands had the back of the body corroding away inside the plating (anodizing?).

It's a nice ride. Not fabulous.

dddd

I had a Bridgestone RADAC, and it's only issue was a shift boss that I recall having to rivet back on.

And then on New Years Day, at Goodwill, for $14.95, I found this one below, a Bridgestone Submariner.

Looked like a brazed or possibly bonded steel frame having normal tubing dimensions, but turns out that all of the lugs, head tube, fork crown and BB shell are aluminum bits, cast directly onto the butted steel main tubes, fork legs, forward ends of the chainstays, and upper ends of the seatstays.
Offered in just two frame sizes, and a Mixte (die-casting molds apparently aren't cheap).

My understanding is that this was a low-cost method of mass-production for these 1970's, very heavy road bikes (mine is the lowest level that they offered) and was re-branded as SuperCycle, distributed by Canadian Tire.

With upgraded (wider/longer) bars and stem, and with a bigger (now 6s) freewheel and clipless pedals, it's currently serving as my daily winter beater, for on- and off-road riding. Yeah, the tires are overdue, I believe that the front "tyre" is original. Rear axle spacing is oddly a full 140mm, with heavily-offset chainline to match, and the seatpost is the internal expanding "quill" type (which is no bueno in terms of the prospects of upgrading to a micro-adjusting saddle clamp).
Frame geometry is roughly 72x72 for a decent off-road riding experience, chainstays seem short enough for decent climbing traction.

gaucho777 

I have an '86 LOOK KG86 - bonded carbon to alloy lugs. I was very excited to get the frame (here from another forum member) as it made a pair with my steel LOOK 753 from the same year in the La Vie Claire livery from Lemond's Tour victory. I rode it for a couple months with "ghost shifting" issues with the front derailleur when pedaling hard or out of the saddle before I realized the BB shell was not attached to the seat tube. (With about 80-100 lbs. of force, the BB shell moves about 2-3mm downward on the seat tube.) I do hope to get it repaired at some point, but I am now reluctant to purchase bonded frames from that era. I'm more open to an ALAN frame which is has a better construction, being both screwed & glued.

AngryFrankie

Nothing wrong with bonded. The adhesive were very high tech, really coming from the airplane industry I think. There was the sort of early wave of straight bonded tubes, Look, Alan, etc, and then during the heyday of high end aluminum frames, bikes with carbon fiber "rear forks" starting showing up, and LOTS of bike companies got in on that. Failures were not common as far as I know, and those were the years I was riding most.

chain_whipped

Rather pre 90's and going to 1987. Still in use, Trek 8000 bonded 7000 series aluminum hardtail mtb. Believe their first series of this type. Super robust, ones body will break before these frames will.

Contrary to Treks first gen of road bikes bonded ally lugs and carbon tubes. Trek admitted defeat and I personally knew a few whom were warranted replaced frames though in all aluminum. And those individuals acquired their carbon bikes, used. Factory rep signed off and all the dealer had to do was cut the old frame in half.

I forget all the details but apparently the tolerance of male lug to carbon tube was too tight and the bonding agent was squeezed out. Then came improved lugs with grooves for the glue. Shortly Bevil Hogg with Brent Trimble's early experience had moved towards monocoque.

With caution I still dig the early survivors carbon tubed bonded lugged bikes. Can't overlook enough and do consider its history, what climate its been in, potential hard life, etc.. Plenty of modern components and wheelsets, gearing and great cranks to have a mid 17 lbs. considered vintage carbon bike that fly.

1989Pre 

I, personally, have never even seen a photo of a compromised lug on a Raleigh Technium. I get 600-700 miles in on mine every summer. The technology had advanced a lot by the time the Techniums/Dynatechs came out: over-sized tubes, better aluminum, better quality control, etc. The technium lug relied on three different ways to keep the lug intact; 1.) the flux itself, 2.) the contraction of the steel lug onto the tubing after it had been heated and 3.) a "lock-ring" that snapped the tube into place when it was inserted to the lug.

Chuckk

Specialized sold their Epic line. I think they were built by Giant.
The second generation (painted lugs) is quite a bit lighter and a real sleeper.


1990 Specialized Allez Epic


1994 Specialized Epic

easyupbug 

I love my '91 (grub screw model) and now 73 with osteoarthritis it is one of my vintage bikes I still put a lot of miles on due to the ride. Being much lighter than my steel frames, 25-35%, it is under 19lbs, has aggressive geometry with 74º seat and head tube angles yet I regularly ride it with my newer titaniums. What many call a noodly frame back in the day my arthritis appreciates the vertical compliance.

macstuff 

I'm glad to hear that these bikes aren't beleaguered and are still being ridden.
There was a vid on YouTube about the resto of a Dyna Tech and during the first test ride, the head popped off. Can't get any replies but I'm thinking the glue failed from the respray and subsequent "stoving" of the paint.
(Heat is how you get glues to release. 300+ F)
The techniums are a bit different animal than the dynas. I've heard from a former spd Raleigh employee that mentioned the aerospace adhesives used on the dyna's but the techniques are put together differently and are Raleigh US bikes, not sold in the UK.
Mine was brought into the co-op and was claimed for a year before being disassembled and readied for scrap.
I took it home and stripped the paint to see the conditions underneath. It seemed ok, it had paint loss only on the lugs so the shop was wary of it. After paint removal and inspection of the joints, I think it will be ok but I'm still a bit nervous abt. it.
It won't be ridden hard by me, but how long it will last is a concern for the amount of effort and money I'll put into it.

sbarner 

I remember a magazine ad for these in which they touted how the ends of the tubes were swaged to provide a mechanical lock inside the "lug." I recall that the bikes were so ugly we foolishly thought the Japanese were not going to be much competition, not realizing that they were just finding their range, walking the tracers to the target.

sbarner 

Here's mine. All tubes firmly attached. Not the original fork. I believe this is the very first version, based on the downtube decal, the rear brake bridge (later ones were a clamp style), and no grub screw on the seat lug (they started cracking when over-tightened). Built up mostly French, with Mavic, Huret Success, and MAFAC LCs. I have a different carbon fork on it now, as that Look/Litespeed one was just too ugly. I'm considering switching to Mavic derailleurs, but the Hurets do shift very well.

jamesdak 

I've got a Raleigh Technium SuperCourse that is quite lovely and surprisingly nice to ride. Upgraded the heavy RX parts to a Dura Ace/Ultegra 10 speed setup.





Hard to capture but the paint on these is really quite lovely with a deep shine to it.

madpogue 

Um, there've been references to '90s bikes as "vintage" here for at least 10 years now. Think of it this way -- 20-ish years ago, when this forum section started, was it surprising to see '70s (or even early '80s) bikes as "vintage"?

Whoa, is that a VHS slot in that borderline-C&V TV?

Back on topic - Yes, I'd say the bonded "thing" really took off in the late '80s. I've read somewhere here on BF that this 1988 Ironman "Carbon" is actually carbon-fiber-clad aluminum. It certainly appears so, peering down the seat tube:

Makes me wonder if some of its contemporaries (Allez Epic, etc), aren't actually constructed the same way.

I recall reading at least one thread referencing the bonds on one of these frames coming loose, rendering it a wall queen. I wondered about mine the first couple times I rode it, but I'm quite certain now that it's just the squirrely nature of the frame material that I'm feeling in the handling, not any reflection on the bonds. It was an impulse buy/build, completed with parts-bin parts, so I'm just going to ride it until... I can't.

velomateo

Glad to hear so many have had good luck with their bonded frames, but I would recommend caution when buying/riding these frames. I purchased an old Vitus Carbon fiber bonded frame some time ago. I purchased it for the groupset really, but while checking the frame once I removed all the components, I was amazed to find I was able to pull the frame apart with my bare hands with not much force at all. Not saying they will all fail, but that glue from the 90's isn't going to last forever, especially if your bike lives in a harsh climate.
Check out this video from youtuber Bike-it.

Trakhak

The Raleigh Technium factory was located in Kent, Washington, making it easy to hire away some of the aerospace engineers who were working in Boeing's headquarters.

I wouldn't be surprised if a joint or two on a handful of Technium frames failed, because it's always possible for, e.g., an aluminum tube to miss a QC step and develop an oxide layer before glue was applied.

But reports of such failures are rare compared to the apparent failure rates of the European bonded frames, to say nothing of the number of cracked brazed or welded steel, aluminum, and titanium frames that have been cited on Bike Forums and elsewhere over the years.

Chombi1 

Just don't put them away wet and they will last a long time.
Better yet, just designate a wet weather, all metal bike that have a welded or brazed construction.

zookster 

My Technium Tri-Lite is a smooth riding bike. One of my favorites!

Trakhak

Which aerospace adhesives are prone to failure caused by getting wet?

DorkDisk

FWIW, this is what it looks like when you saw through the top tube of a bonded Trek frame.

Pretty much what you'd expect to see: carbon over an Al lug with bonding agent squeezed through.