Both the San Quentin’s shape and Marin’s marketing claims are radical. The US brand says the San Quentin 1 is suited to both enduro and downhill trails, and should even perform on dirt jumps, and its raked-out head angle and stubby stem hint at these descent-focused intentions.
Marin San Quentin 1 frame
As with most bikes at this price, the frame is made from aluminium – in this case, 6061 alloy. A small brace between the hydroformed top and seat tubes boosts strength and allows a lower standover height, while the top tube and seatstays are formed to give a single line from head tube to dropouts.
These use the new Boost QR spacing (141mm), designed around a wider hub, which potentially contributes to a stiffer wheel build.
The rear brake hose and gear cable run along the down tube for ease of maintenance, and the seat tube is ported in case you want to upgrade to an internally-routed dropper post.
The geometry is right where it should be on a bike aimed at thrill-seekers. A decent reach (464mm on the large) is paired with short 423mm chainstays. The head angle is slack, at 64 degrees, while the seat tube is steep-ish, at 74 degrees. Sitting 311mm off the ground, the bottom bracket is quite low compared to similar bikes.
With no clutch mechanism on the rear mech to help keep the chain on the single chainring, it’s a good thing Marin have fitted a chain guide. Steve Behr
Marin San Quentin 1 kit
The San Quentin 1 is available from independent shops, and having more stages to the supply chain inevitably chips away at its value for money. That said, the kit is all reasonable stuff. You get a 1×9 Shimano Altus-based drivetrain with a chain guide to help keep the chain on, in place of the normal (pricier) clutch-controlled rear mech.
The crankset is Marin-branded and uses a square-taper bottom bracket, while the cassette is from SunRace and has a 11-36t range. Tektro supplies the brakes, which have a decent lever feel and reasonable power.
Up front, there’s a coil-sprung, 120mm-travel SR Suntour XCM32 fork. A preload dial allows rudimentary tweaking to suit different rider weights, but there’s no rebound-damping adjustment. It does have a bolt-thru axle for extra stiffness, though.
Wide (29mm) Marin-branded wheels provide good support for the 2.3in tyres – although my bike came with Schwalbe Hans Dampfs, not the Vee Crown Gems on the spec list.
More own-brand kit finishes the bike, including a 45mm stem and wide 780mm bar.
Marin San Quentin 1 ride impressions
It’s the head angle that’s the most noticeable aspect of this bike. While not so slack as to feel lazy, it gives a heavier feel to the handling on flatter tracks and when spinning uphill, with a touch of side-to-side flop when the front wheel turns.
It’s not too much of an issue on climbs, but on mellow terrain it adds to a feeling of slight laziness and lack of drive. This is exacerbated by the bike’s 15kg weight, some of which is in the wheels.
Muscling the bike through tight turns is nice and easy with the wide bar, which also opens the chest on prolonged climbs. Steve Behr
The fairly limited range of the cassette makes steeper drags a touch tougher, but at least the steep seat angle helps put your weight in the right place between the wheels and over the bottom bracket.
All of this somewhat misses the point of the San Quentin though. As soon as there’s any negative gradient, it starts to come alive.
With the stretched front-end putting the wheel well out ahead and the short stem/wide bar combo giving you commanding control, the Marin oozes confidence.
Weight the front wheel and the bike is steadfast over roots and rocks or down chutes. The fork is basic, but if you can put up with a bit of trail chatter, it deals with the big stuff fairly competently.
On smoother trails with berms and drops, the low-slung bottom bracket lets you really load the pedals into corners, generating speed, and the Marin is stable in the air too.
I’d like a touch more smoothness from the fork and a quieter drivetrain, but if you just want a bike for pounding steep descents, the San Quentin 1 should cope with most of what you throw at it.
Marin San Quentin 1 geometry
Seat angle: 74 degrees
Head angle: 64 degrees
Chainstay: 16.65in / 42.3cm
Seat tube: 19.09in / 48.5cm
Top tube: 24.61in / 62.5cm
Bottom bracket height: 12.24in / 31.1cm
Wheelbase: 47.72in / 1,212mm
Reach: 18.35in / 46.6cm