After 3 rides on the Jet 9 I put my Yeti ASR sl up on ebay. It is that good.

 The Jet 9 in Niner’s version of the full-suspension race bike. It has 3 inches of travel front and rear (short link 4 bar), aggressive geometry, a short wheelbase, and of course 29 inch wheels. They claim that it is also their most versatile bike. And I guess I believe them, if by versatile they mean riding everything should be ridden flat-out. You can go to the Niner website to get the rest of the details.

The build:
Large black ano frame,
Fox F29 fork
Sram X.9 shifter X.0 derailluer set up 1X9 with a Noir crank
Stan’s Arch rims laced to DT 240 hubs converted to RWS thru-bolt
Schwalbe Racing Ralph 2.25 tire front, Kenda Small Block 8 rear.
Avid Juicy 7 brakes
East EA 70 stem and seatpost, EC 70 flat bar
Fizik Gobi saddle
ESI grips
Egg Beater pedals
Weight: not heavy but not super-light.

Pedalling: The suspension is very efficient. With the propedal in the “off” setting I can’t detect any pedaling induced bob while seated. Standing to pedal does cause a fairly significant amount of up and down motion. The movement can minimized by using setting 1 on the propedal or hitting the lockout on the fork. Note that according to forum postings the factory settings on the rear shock are high low speed compression damping (i.e. propedal when the propedal lever is in the “off” position) and medium rebound damping. So it is possible that the efficiency is partially due to the platform effect of the low speed compression damping. That being said, Niner uses the combination of shock damping and anti-squat suspension design very well. For 90 percent of riding the additional propedal is unnecessary. This setup makes it possible to save the propedal for extended climbs to get that extra platform effect. Otherwise leave it off and enjoy the ride.

Suspension: Set up is easy following the Fox recommendations. Once dialed in, the bike uses its suspension incredibly well. The overall feeling is that bike uses only as much travel as it needs to, even with the propedal “off.” It gives you enough small bump sensitivity to be Epic ride worthy, takes medium sized hits in stride without getting sloppy, and saves a little something in reserve for those times when the rock/drop was just a bigger than expected. With the propedal on the effectiveness of the suspension is compromised. You loose sensitivity on the small bumps and the travel feels like it is cut in half. Its a fair compromise on climbs when efficiency is a priority. But if the trail has lots of up and downs keeping the lever in the “off” position is the way to go.

Cornering/Maneuverability: If you ever wondered what it is like to be a Ninja you need to throw a leg over the Jet 9. Niner has truly put flick-able into the 29er vocabulary. Need to slalom through tight single track or an over-sized rock garden? No problem. Tight switch-back? No problem. Need the bike to rotate a little mid corner? Done. Combining aggressive geometry and a short wheelbase eliminates any of the cumbersome feel that 29ers are susceptible to. The trade-off of course is that the Jet 9 is not quite idiot-proof. The big tires do allow impressive lean-angles allowing you to rail high speed sweepers, but you need to pay attention at the edge of traction. And grabbing a handful of brakes while turning is a no no, unless you are trying to turn 180 degrees this instant.

Braking: The suspension stays well controlled and reasonably active under braking. You will still feel braking bumps but without significant harshness. Again though, the short wheelbase and aggressive geometry means that the bike is not idiot-proof. If you do lock up the rear, the bike will demonstrate its ability to rotate quickly. Going down steep, loose over packed/gravelly/babyheads, requires a delicate touch on the right brake lever.

Climbing: Flip on the propedal and you’ll be headed up-hill faster than your fitness should let you. At speed the Jet 9 deserves every over-used description out there, only its better. On slower technical climbs, the bike is still plenty capable but has a bit of a short attention span. You do have give frequent little reminders as to where you are headed.

Descending: The combination of big tires and fantastic suspension makes the Jet 9 an over achiever when things point down-hill. It feels fully qualified to descend any trail that you can ride/carry it up. The short wheelbase also makes it easy to loft the front tire for obstacles and drops. Just be realistic, the bike has 3 inches of travel. Its not going to fit in on the knuckle-dragger circuit. (Although, remember that part about the suspension saving a little something, well you only find that kind of thing out when you find yourself committed to a decidedly un-cross-country sort of line).

Noodle Factor: Niner has gone through some growing pains with the Jet 9. It had to recall rocker links that where breaking, and they also redesigned the rear triangle. This particular bike has the new rockers but the old triangle. Overall, it felt adequately solid but not head of the pack solid. Mostly what I noticed was some rear wheel deflection on baby head size rocks. Converting to the DT thru-bolt made a noticeable improvement. With the thru-bolt set up I would not actually ding the bike for stiffness. Niner also has had some issues with less than durable paint. The anodized finish however has proven quite tough in more than one encounter with a coarse rock surface.

The competition: In my limited scope of the world, I see the Pivot 429 and Gary Fisher HiFi 29er as two of the major competitors for the Jet 9. Clearly the former are less race oriented but they do help tease out the strengths and weaknesses.

Hands down the Jet 9 suspension is the most effective of the 3. The 429 gives a bit too much to early, while the HiFi is a bit of a mess without propedal.

Riding the Jet 9 back to back with the 429 you will notice that the Jet isn’t quite as stout. It’s not far off but the 429 is probably more appropriate for riders with a habit of breaking things. The Jet 9 does feel more solid than last years HiFi. But take note that the HiFi has been over-hauled for ‘09 with the promise of better stiffness.

The Jet 9 easily the quickest handling. It makes the 429 feel almost oafish on the twisty stuff. The trade off however is losing some of the point at a line and it will get you there reassurance that the HiFi provides in corners, and the 429 has on technical climbs.

And under hard braking, again the Jet 9 could use a little bit of the stability of the 429.

Advice: Thru-bolt type skewers provide a tangible increase in stiffness, improving tracking when thru rough sections. Also, I know its a racy bike but resist the impulse to skimp on rear tire traction. The small block 8 which worked ok on a 429 was not effective on the Jet 9. A second Racing Ralph on the rear would have been a better choice. And going with a 100mm fork is worth a consideration if you are looking for ways to slow down the handling a bit (something I will experiment with in the near future).

Overall, the Jet 9 is an incredibly fast bike that likes to um…. be ridden fast. It needs to be on the short list for anyone interested in a full-suspension race bike (even if you think you want a 26 inch bike). It also doubles well as a trail bike for anyone who enjoys doing most of their riding flat-out. Those who prefer to explore at a mellower pace, or that tend to break things just by looking at them, might not get along quite as well with the Jet 9.