Before we get stuck into the review, let me get it out the way that I'm a Momsen fan, specifically a Vipa fan. Having collectively ridden and owned four Vipa iterations and builds (even the aluminium AC), I was very excited to test out the Ultra.
First encountering the prototype bike ahead of the 2018 Cape Epic I have to say I was unsure of the aesthetics but was encouraged by the bold design and engineering choices. Into production, thankfully the luminous yellow temporary decals were replaced with more subdued production designs.
Seeing the production bike in the flesh I was more at peace with the design. The stout, angular tubes are striking and unusual and remind me somewhat of a Stealth Bomber. While evoking a hint of boyish glee and having had some time to grow on me, I'm still not sure if I love it.
The Momsen Vipa Ultra is typically sold as a frame kit which includes the frame, rear shock, headset, rear axle, seat clamp, protective covers and storage accessories. MSRP for the kit is R 42,500.00 and it’s available direct from their website.
The frame has a number of features intended to service the stage race hungry South African market. These include support for two bottle cages inside the front triangle, both accommodating full-size bottles, and without the need for any adaptors as with previous Vipa models. There is also a mount for a third bottle cage beneath the down tube for those needing more hydration on long stages or ultra-endurance events. The frame does also cater for a front derailleur should you want one.
In terms of sizing and geometry, the Vipa Ultra is only available in two sizes (Size 01 and Size 02), which they say should cover range of a traditional Medium, Large and (smaller) Extra-large frames. Even on the smaller size, the Vipa Ultra has lengthy reach at 451mm (and 465mm on the larger size) which makes the super short 40mm or 50mm stem almost a necessity.
Two notable features on the frame are the built-in storage compartments: one on the top-tube which contains a soft zipper bag to stash your things, and another at the base of the down tube which seals with a sturdy rubber lid. Being a fan of light pockets during stage races (and most rides) these could be useful.
The frame’s headtube is particularly short at just 90mm and 110mm on the two sizes making for a low front end. The geometry is adjustable via a flip-chip which switches between slack and steep giving a head angle range from 67.5 degrees (slack mode, 120mm fork) to 69.1 degrees (steep mode, 100mm fork). Our test build arrived with a 120mm Rockshox Revelation preset in “steep” mode, giving it a 68-degree head angle.
- FrameVipa Ultra Carbon, Toray Carbon, Boost 148 Rear, Threaded 73Mm Bb Shell, Dual Bottle Mount With Optional 3Rd Bottle Placement, 100Mm Rear Wheel Travel, Flip-Chip Geometry Adjustment
- ForkRockshox Revelation Rc, Boost 110, 15Mm Thru-Axle, 120Mm Travel, Rebound Adjust
- ShockFox Float Dps, Performance Series, Trunnion, 3 Position, Evol, 185Mm
- WheelsNo Tubes Ztr Arch S1, Tubeless Ready, 32H, Shimano M7010 Boost centerlock hubs
- TyresVee Tire Co. Rail Tracker 29 X 2.20, Tubeless Ready
- ShiftersSram Gx 12-Speed Trigger
- Rear DerailleurSram Gx 12-Speed
- CrankTruvativ Stylo, 12-Speed, 32T, 175Mm
- Bottom BracketSram Gxp Threaded 73Mm Dub
- CassetteSram Nx 12-Speed 11-50T
- ChainSram 12-Speed
- SaddleMomsen Custom
- SeatpostX-Fusion Manic Dropper
- HandlebarAlloy Forged Oversize 31.8mm ,12mm Rise, 720Mm Wide
- StemCustom Vipa Ultra – 2 Stem Lengths Supplied / 40mm / 50mm / 31.8mm Bar Bore
- HeadsetCustom Vipa Ultra – Integrated Type
- BrakesetShimano M8000 Xt Hydraulic
- Measured weight (Size)13.58kg (Size 01 / Medium)
- Retail PriceR 78,500.00 (or R 42,500 for the frame-kit)
On the bike
Let's start with the obvious standout features: the two built-in storage compartments in the top tube and down tube.
The built-in top tube storage bag is great. The zipper keeps snacks or essential spares safely stowed away but allows easy access while on the bike - a great touch for stage racing and a good size to fit all you might need while on the go. One small irritation was the zipper tag tapping on the frame while riding causing a faux rattle and a bit of frame rub, but this was easily solved by tucking in back into the zip before closing completely. Momsen have since resolved this with a shorter tab and switched the zipper orientation to run bottom-to-top.
The lower storage area on the down tube was where I struggled. The shape and depth of this compartment make it tricky to store a typical spare tube in it (which, in a stage race is what I want on the bike and not in a pocket). It did, however, comfortably house a 20g CO2 canister plus a tyre lever and other small tools. Although the compartment is lined with neoprene, on most trail surfaces I experienced an irritating rattle. Again, quite easily solved with a small cloth to keep everything separated (a sunglasses case worked a treat) or by taping the contents to the inside. My primary struggle was that the rubber lid just refused to stay shut and on a ride featuring any kind of rocky bumps the compartment exploded open, usually at a speed which efficiently distributed the contents all over the trail. Even after shaving the neoprene liner to ensure a proper fit I still had trouble with this. It’s an easy enough issue to solve with some trusty tape to keep the contents in place or secure the lid, but it’s one of those things you do expect to work “out of the box”.
The bike itself is described as [an] "Unashamedly Focussed. Zero Compromise. Stage Race Weapon." As far as stage racing goes there are certainly some clever touches like the top storage compartment and, despite the slack(ish) head angle and a 120mm fork, the bike has an aggressive stance thanks to the low stack and short stem. The bulky tubing does give the bike an incredibly stiff, sturdy feel which might well deliver the efficient power transfer you want on long open roads, but for me, it also steals some of the character and playfulness that I enjoyed on the Vipa Race. Make no mistake, even on twisty downward trails the Vipa Ultra is fast - I set a good few PBs on my early outings on this bike. But the stiffness coupled with the hefty weight of the bike in this build spec (13.58 kg for the 120mm, Stans Arch build, with pedals) meant it resisted any sort of playful flick or hop on the trail.
The weight aside, the stern characteristic of the bike is perhaps just staying true to the promise of a "Zero Compromise. Stage Race Weapon.", but the inclusion of a dropper post and 120mm fork in this particular build did have me expecting some more playful trail habits.
Realising that the weight of this particular build could be playing against it, we switched out the fork for a much lighter 100mm Fox 32 Step Cast, and the Stans Arch wheels for some feathery XC focussed options to test the shorter travel set-up and shed a few kilos. Ironically, this build felt more fun and playful than the 120mm option thanks to weight loss and the more nimble, slightly steeper front end. While still stiff and uncompromising, the ride felt a bit more natural and, well, fun!
When it came to the adjustable "flip-chip", my experience was that the Vipa Ultra felt best in the 68-68.5 degree head angle range. This meant "steep" mode with the 120mm fork (68 degrees) and “slack” mode paired well with the 100mm fork (68.5 degrees). Of course each rider will have their own tastes here, but it is useful to have the options provided by the flip-chip and fork selection.
Although the lighter build did improve the feel of the bike, it still weighed in on the heavy side (11.92kg with pedals) for a stage race focussed bike with an upper-end spec, okay plus a dropper post. GX is not the lightest in the SRAM line-up, but I can only assume that the extra carbon required in the frame to accommodate the storage has also added a bit to the weight. Given the choice, I'd gladly forgo the bottom compartment in favour of a few (hundred) grams. Momsen did give us some insight on this and, according to them, foregoing the bottom storage area would only account for a 70g weight saving.
My overall take is that the Vipa Ultra does largely deliver on the promises of its tag line. It has a fast, race weapon-like feel to it and in many respects, aside from weight, is all about zero compromises. But I'm not sure I like that. Perhaps I'm not the target market, but as an avid stage racer, I do also enjoy a bit of fun on the trail, whether mid-race or a relaxed weekend outing. The Vipa Ultra just isn't a bike that delivers for both use cases, but given the hyper-focussed marketing message, that might well be intentional.