Principia frames have been with us at PBK since they celebrated their 20th anniversary as bike frame manufacturers earlier this year. 20 years might not sound like a lot compared with the likes of Colnago and Cinelli, but considering Cervelo have only been going for 16 years it shows that an awful lot can be learned in a short time if you have the know how and drive to develop and hone your products.

“We have pioneered cycling – and we are still doing it”

Not a phrase to be used lightly! “When the first Principia frame was unveiled in 1990, it represented a revolution in terms of both weight and stiffness. It is with a great sense of pride that we now celebrate our 20th anniversary. Over these past 20 years, we have firmly established the Principia brand as one of the most innovative frame manufacturers in the industry”. With this anniversary celebration, we want to remind you of some of their most memorable creations – who knows, perhaps you used to ride one of them?

The 1990s:

A Principia RSL frame weighing only 1160g achieves the verdict ‘outstanding’ at the RWTH Aachen Test Institute ’92.

Principia kicked things off in the 1990s with their alloy RSL frame, weighing in at only 1160g. The frame even achieved the verdict ‘outstanding’ at the RWTH Aachen Test Institute in 1992. Even by today’s standards, an 1160g alloy frame is a serious piece of kit (a 2011 CAAD10 weighs a ‘claimed’ 1150g!).

A Cinelli Experience, while at the less expensive end, weighs in at a claimed 1370g. So the fact that Principia are at the forefront of technology can’t be argued with.

Their influence and impact in the world of Triathlon also can’t be ignored. The TT28 was the most used European frame at the 1996 and 1997 Hawaii Ironman contest.

This forum post about the TT28 sums it up well:
“Principia are utterly, stonkingly, pant-wettingly, achingly, magnificent. By all means look at all those lesser (but more expensive) frames, but Principia are the way forward. I’ve never seen a bad review of them and I remember one review by some scouser (Chris Board – something or other) saying he thought the Rex pro was his favourite.

I’ve had a TT28 for about 5 years now and it is the best frame I have ridden by some way (that includes many of the Italian exotica and the yank high tech stuff) I’m thinking of getting another, but the original is still going strong.

Very light, very strong, stunning welds, tough finish to the anodised frames. Just buy one, you will not regret it for a moment.”


Principia introduced the R.E.X in 1998 which ‘turned into a test winning classic’.

Team Acceptcard rode the frame for two consecutive years, Team Chicky World also used the frame at the same time with Team Linda McCartney giving them a go in 2000 while Team Fakta rode Principia frames from 1999-2002.

The New Millennium:

This heralded a new way of thinking for Principia, inspired by nature the tubing took on an ellpitaical profile and the Ellipse Project was born in 2002. Since this Principia have had some what of a resurgence with Team GLS using the frames and more recently Sean Kelly’s An Post team during their 2009 and 2010 season.

With special Paul Smith editions and continuous R&D lets take a look at what’s on offer from the Danish manufacturer now.

The 2011 Principia Range at PBK:

To give you an insight into this years Principia range here’s the lowdown on 3 of their finest frames for you to peruse.


First up is the previously talked about R.E.X. A 58cm version of this alloy frame has already been ‘set aside’ for one member of the office due to it’s understated looks, top quality tubing and it’s shiny paint work!

It features ultra neat welds, a BSA standard BB to suit most setups and a replaceable gear hanger just in case the worst happens!

R.E.X Technology:

The Ellipse Project is the latest generation of Principia’s trademark elliptical bottom bracket and head tube design. The increased diameter of the tubes adds rigidity and strength without increasing weight. The Ellipse Project gives you more efficient power transfer and more control when it counts.

PMA is the latest generation of Principia’s acclaimed aluminium technology with conified and triple butted aluminium tubing. These frames are made from a newly developed alloy with improved comfort properties that set a completely new standard for aluminium frame tubing.

The R.E.X comes supplied with Principia’s own Flow fork which is one of the most advanced on the market. Several hundred hours in the laboratory give the best balance between weight, horizontal stiffness and comfort in relation to vertical shocks from the road.

At just 320g it is Principia’s lightest ever fork, the tapered head tube and ovalised crown all remind you of the work done over the last 20 years to find the very best shape.

Add in a frame weight of just 1140g and you have the possibility of building up a very light, alloy bike.

Have a closer look at the R.E.X. on the PBK site.


The RSL C16T is the mid-range option from Principia featuring a full carbon frame and fork, providing a fantastic stiffness to weight ratio.

RSL C16T Technology:

Utilising TIW2 welding technology and the Ellipse Project elliptical bottom bracket and top tube design, Principia have spared no punches in creating frames at the forefront of bicycle frame manufacturing.

The RSL C16T’s Design 2 Size technology also ensures each frame is optimised for its individual rider. Traditional frame design uses tubing with identical diameters and wall thicknesses for all frame sizes,  thereby making the smaller frame sizes too heavy or the larger frame sizes insufficiently strong and stiff. To combat this, Principia’s Design 2 Size technology optimizes the tubing specifications for the individual frame sizes ensuring optimum riding characteristics for riders of all sizes.

Have a closer look at the RSL C16T on the PBK site.

Revolution Integral C40T:

Next in the line is the ultra stiff Revolution Integral C40T.

The sheer size of the BB area and the fact it has the new BB86 fitting gives a clue to this frame’s intentions. Stiff, stiff and stiffer was the key and is a theme which runs through the entire Principia range.

What hardcore racers desire more than anything else is lateral and vertical stiffness. The Revolution Integral C40T delivers this with stiffness that is unsurpassed in the industry. Numerous independent tests have all corroborated this claim. When maximum power transfer and responsiveness is what you need, you know that you can count on this frame to deliver.

Revolution Integral C40T Technology:

In addition to all the technologies we’ve already mentioned, the Revolution Integral C40T features the extended Integral Post System seat tube which makes the necessary overlap between seat tube and seat post on traditional frames redundant.

This allows Principia to remove excess material achieving an even better stiffness-to-weight ratio.

Have a closer look at the Revolution Integral C40T on the PBK site.

Evolution Track:

There’s also a special mention for the sleek Evolution Track frame, available in white and black, it’s purely built for track use.

Have a closer look at the Evolution Track on the PBK site.

If you’d like to find out more about our Principia range please click here.

Also don’t forget that we’re always to hand to offer advice and help on purchasing what is a very important item to get correct.

Let us know below what you think about this new range and if anyone has ridden a Principia in the past. We always welcome your opinions as they provide a great source of information for us and our product teams.



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