Factor O2 VAM Review.
After 8 months of riding an O2 VAM, it’s time to share my findings. The frame is a 2021 size 56 rim brake, built with Dura Ace Di2. Wheels are various carbon clinchers, and I have also run Shamal Ultra’s as a stiffness benchmark.
My goal when purchasing the VAM was to get a very light rim brake frame with room for 30mm tires. The VAM really succeeded here, the frame is about 720 grams and the cut fork is 259 grams, and there is room to spare with 30mm tires. The measured gap between the chainstays is around 40mm so even 32mm can work – this is huge for a rim brake frame. The idea was to have a set of fast wheels (50mm deep with Corsa Speed TLR) for when I have to keep up with the fast guys, and a set of comfort wheels (35mm deep with 30mm Corsa and latex inners) for slower more adventurous riding. The O2 VAM really is unsurpassed when it comes to weight and tire clearance, my main selection criteria. Also noteworthy is the quality of construction which is flawless and clearly on display due to the raw carbon finish.
But things have proved to be less satisfying in other areas, particularly the handling characteristics of the frame. While the geometry is very well suited to me, the bottom line is that the frame so flexible that the front and rear wheel do not stay on the same plane during hard cornering. This has significant effects on the stability of the bike when g-forces increase in high-speed curves. Pressure on the outside pedal causes the bottom bracket to move enough laterally so that the rear wheel pivots toward the inside of the turn. Meanwhile the fork is sort of left hanging out, pointing more to the outside of the turn. Literally the frame diamond is folding in the middle causing the wheels to be pointed in different directions. The net result was a bike that wanted to drift wide under high-speed pressure. To hold something resembling a decent line requires constant steering and/or lean angle corrections. The bike was inspected by a dealer and the frame was determined to be perfectly sound and the build without fault. There’s no loose headset, bad wheel, or alignment issue causing a problem – this is the inherent nature of frame. It’s so flexible that giving the bars a good wiggle when straight running gives the sensation that the whole bike is made of rubber. The feel is similar to the first generation of carbon Giant TCR. I think it is important to note that I am 76kg (170 lb) and do fall on the bigger, fitter side of hardcore road cyclists, and I would not be at all surprised that someone on a smaller size VAM, or with a 10kg lighter body would have a completely different experience. As well, I admit that the instability detailed above is most pronounced at fairly extreme lean angles and speeds - approaching the limits of tire adhesion.
There is an easy solution to the high-speed cornering problem, and that is to transfer some of the pressure from the outside pedal to the inside pedal and saddle. This reduces the forces that cause the frame to fold, and a stable radius can be more or less maintained. Still, when leaned over, rolls and ripples in the road produce a noticeable steering effect. As the frame bends from the fluctuating forces, the wheels steer this way or that on their own. Although it is a minor thing and easy enough to deal with, it is still a bit unnerving. And it is something no other bike I have ever ridden has exhibited, certainly not to a noticeable degree.
The lack of frame stiffness also was an issue in another area as well that I just could not resolve. Rear brake rub was constant with any decent effort out of the saddle. With the brake calipers set so wide that the levers came all the way to the bars, I would still get brake rub. With the brake pads set at a more reasonable distance from the rim, I would occasionally get brake rub just cornering. And it’s not the wheels. Three wheelsets have been tried (remember the Shamals above) and they all rubbed on the VAM, and none of them rub on any other of my bikes, even with the brake pads set much closer. On the stand I tested the amount of force needed to bring the rim in contact with the rear brake pad. I put my thumb on the seatstay at the brake bridge and looped my index finger over the tire and pinched the two together. I expected the wheel to flex-twist toward the pad. Instead, the wheel stayed near vertical, and with relatively little force, both rear dropouts moved horizontally until the rim touch the brake pad. The wheel is literally stiffer than the rear triangle (with the rear hub clamped in it!). I immediately conducted the same test on all my other bikes and they were all reassuringly rigid. The VAM was alone in this display of flexibility. So perhaps much of the handling issues are a function of an overly flexible rear triangle.
To a person, everyone at Factor was extremely responsive to my enquiries. In fact, all my dealings with the company have left me with the impression that these are really good people who care passionately about doing an excellent job. I had a fair amount of communication with one of the technical people at Factor and they did not dispute my findings. But what can they do? Acknowledge that they missed the mark on the O2 VAM? That’s not going to happen. The closest I got was something along the lines of “that’s why some of our stronger riders prefer the regular O2” which I was told was 5 to 10 percent stiffer.
Still, I figured a pro tour tested frame meant that I did not have to worry about handling characteristics. That has proved to be a very naïve assumption. When I enquired specifically if any of the Israel Startup Nation riders had issues in cornering stability on the O2 VAM, I was met with silence. I also asked if any other customers had complained about frame stiffness (knowing that some had) and again, I was met with silence. I do not fault Factor at all for any of these non-responses which in effect told me what I needed to know, and I imagine that was the intention. Furthermore, I am grateful for the level of engagement and significant level of detail regarding the design of the bike that was shared privately with me.
Now a person might accept the idea that such a low weight frame must have these limitations. But what of my Parlee Altum. It is about 100 grams heavier and suffers no such problems. It is remarkably stable in all situations. The Altum geometry and steering characteristics are not ideal from my perspective (it’s not as responsive to lean angle as I would like), but the damn thing never blinks no matter what I throw at it. Perhaps that 100 grams is a lot more important than I think. But by the same token, the Altum is at least an 8-year-old design. The main problem with the Altum for me is lack of rear tire clearance which is what prompted me to look at the Factor in the first place. Noteworthy also is that the Altum, despite its more solid build, is a more comfortable bike that the O2 VAM.
So fine, the Factor O2 VAM is crazy good going uphill, plenty fast on the flats, and really, what business do I have cornering at the limits of tire adhesion every time I go out. I am at the stage where I should dial the demon descending back a bit. I had in fact made peace with the handling characteristics, and I must admit I didn’t mind having an excuse to descend in a slightly more conservative fashion. Overall, I feel that the O2 VAM is a fast, efficient machine and really fun to ride as long as I respected its limits. And were it not for the brake rub, I would have been perfectly content to keep the VAM indefinitely. A 6kg bike built with basic Dura Ace Di2 is a blast. Slap on the Corsa Speeds and that’s a crazy fast setup on any terrain.
Ultimately, the brake rub was a deal breaker for me, and I could not live with the frame. Again, Factor was great. They wanted me happy and offered to exchange the bike without hesitation. They worked closely with the local dealer that is staffed by a terrific group of guys and came up with an O2 disc, a spare team bike from one of the teams Factor sponsors. The reason for switching to disc is that according to Factor, there is essentially no difference in the rear end of the VAM and the regular O2 in the rim brake versions. This meant the only solution for me was a regular O2 in disc brake form. And lest anyone be concerned that I am ending up with a less expensive frame, trust that in the end the arrangement has provided me with fair value. As to how I feel about going from a 6kg rim brake bike to a 7.xxkg disc bike, I am not yet sure. I still have the Parlee which is close to 6kg.
Epilogue
After waiting for various parts, and with some wheels borrowed from my rain bike (I have a set of LB WR50/Carbon Ti on order), I was able to complete the build on the O2 disc
At this time of year, the best places to test a bike’s descending manners are mostly off limits due to wet roads, but I do have a few very tough corners on my regular route, and I can happily report that the O2 is not just good, it is excellent. It does not just address the handling weaknesses of the VAM, it excels in those areas. I have only logged about 150km on the new bike, but my initial impression is overwhelmingly positive. I put the O2 through some rough corners at high speed and it held its line predictably while absorbing road cracks and surface changes with unexpected calm. While it is not a super stiff bike, it does have a good balance of rigidity and flex for my tastes - I hate bikes that feel like riding a brick. For certain the “made of rubber” feeling of the VAM is gone, and there is a sense of solidity about the whole package. The surprising level of smoothness is a bonus.
I am also particularly happy with the steering characteristics. The head tube angle and fork offset create what I feel is the perfect response to lean angle. I can easily exit high speed turns “tight” and “high” as opposed to fighting a bike that wants to drift wide.
Oddly, the O2 feels more comfortable than the VAM. I know this does not make sense, particularly because I am using 28 spoke wheels that are presumably stiffer than the 24 spoke wheels I used on the VAM. I must admit I am a bit baffled how two bikes that are so similar can behave so differently. I guess a little stiffness goes a long way.
In the end it has been a very roundabout experience with Factor, but they were pros throughout and I remain an enthusiastic fan of the brand.
I own one but I'm never gonna test it hard so I'm just happy that it's a light disc bike. 
