The Venn VAR77 rim is truly unique in the world of carbon rims for a number of noteworthy reasons. I built up my first pair recently for a client who wanted some special track wheels for a road fixie project he was bringing to life. We decided on a perennial classic track hub by Phil Wood. A very good choice. The front and rear wheel would be suspended by 24 CX Ray bladed spokes in a cross 2 symmetrical lacing pattern.
The Venn VAR77 carbon rim was chosen for its extreme depth and its aero profile, though it had a few other attributes that put it in a class of its own that we’ll look at here.
It has the distinction of being the first carbon rim in the world to have utilised AI or artificial intelligence to help determine its aero profile design. Very cool!
77mm deep!
That rim was subjected to an independent test and found to be the fastest for that particular depth in existence. Proving beyond the shadow of a doubt that an AI influenced design could rise to the occasion and succeed.
Here’s a table showing how the VAR77 performs against some other rims from Venn.
But as amazing as that is, it’s not the whole story behind the VAR77. It also has a construction methodology that is completely unique for a carbon rim and that’s a filament wound method instead of a standard carbon hand layup that every other rim in the world utilises. Filament winding is not that new in of itself, but only recently has this technique been employed in manufacturing carbon bicycle rims.
The end result of this method of rim construction is a very refined and accurate computer controlled process that raises the bar for carbon rim quality.
I noticed this new level of quality when building these wheels. Both sides of the rim were absolutely flat which is often not the case on a carbon rim that is made with a traditional hand layup. I also saw that the rim was rounder than you would see with a regular carbon rim. This greater degree of accuracy in this area enabled me to get this wheel perfectly round. Impressive!
It also retained that perfect shape when approaching the final tension. This is sometimes a small issue when building with normal carbon fibre rims. They can start to deform at higher tensions. This deformation may only be a very tiny amount but its evidence that the material is not responding well to high tension. The VAR77 held its own nicely even at 120 kgf of tension for the rear wheel.
The Venn VAR77 and the Phil Wood Pro track hubs look absolutely stunning and quite imposing.
The final test will of course be the ride quality. I will be grilling my client for his thoughts on how the Venn’s feel on the road. I already have a good feeling about these wheels based on how these rims responded in the truing stand. Over the years my intuitions about ride quality have mostly proven correct just from my conclusions about how the rim felt while being built. That may sound odd to some but you can learn a tremendous amount about a rim just by its behaviour in the truing stand. I’ll be back later with the conclusions on the ride quality soon! Stay tuned.
