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I broke this bike. Now I have a Speedfox SF29

In Feb 2012, I acquired a full-suspension MTB, as a reward for a weight-loss milestone. According to the retailer, they were the only stockist of the 2011 Speedfox SF03 in Australia - so this is a fairly rare bike. Just the way I like it.

The Speedfox is pitched as a Marathon bike, so the geometry is a bit more slack than peak XC bikes, and the wheelbase a bit longer. It has 120mm of travel where XC bikes are clustered around a more pedal-efficient 100mm, and is meant to be versatile and efficient, while easing fatigue. It's also a slightly larger size than I'd have bought for a singletrack toy.



The Speedfox on its first shakedown ride

The Speedfox on its first shakedown ride



It's a BMC Speedfox SF03, and it's led to something of an epiphany. I have no idea why I didn't go full-suspension years ago.

There's 120mm of travel at either end, with optional dual lockout - quite important with that amount of travel. It's mixed Deore/XT with Avid discs and a lot of BMC/Scor equipment (and thus some scope for slimming down the weight). I did a 40km shakedown ride along the Cooks River bikepath on the day we bought it, and I have a couple of observations:

  • The front wheel looks a long way away compared to my Hardtail, which is a 90o long stem right above a very short-travel fork.
  • The seat needs to be counter-intuitively high, since the suspension lifts the bottom bracket significantly higher than a long-term hardtail rider might expect. So mounting up means tipping the bike hard to the side. The BB is maybe two inches higher than my hardtail, on a slightly bigger frame (L, 19.5in seat tube, which BMC's own estimator says is just right for my ~180cm height)
  • It also encourages a somewhat sit-up-and-beg position, meaning the fatigue profile of a long ride is quite different to the original late-90s XC race setup I used to run. In other words, it hurts a bit and I need to adjust to it. Ibuprofen might help.
  • The lockout is superb, but I did forget I had it on at one point, meaning I hit some bumps rather harder than I expected. Hopefully this will become second nature over time.

I've since taken it out offroad on the McMahons Lookout Firetrail. Some more observations:

  • Wow, does it ever reduce fatigue? My shoulders were undamaged after 40km of offroad which on the old bike would have punished me badly. Likewise my rear end.
  • Stability and confidence on fast downhills is supreme. At one point, MapMyRide told me I was doing over 60km/h. The little voice gets fairly hysterical with numbers larger than 60.
  • climbing ability is through the roof. Just plant your rear end, pick the right gear and grind. The rear end stays stable and you find yourself at the top of the hill. Eventually.
  • I'm going to be heartbroken when I first ding this bike. I suppose I was with the previous one, too, but I got over it.
  • Very important to stay the brake calipers during transport. I got brake drag after coming back which I think is due to knocking a lever in transit with the wheels off.

More observations after Narrowneck 19/2/12

  • Taking off over waterbars requires getting one's weight back. The rear shock does rebound a bit on takeoff, meaning it's easy to end up nose-down. Took a little while to get used to, but by the end the air was big and the landing smooth. Weight back to take-off, coming forward to a more neutral stance in the air.
  • Stick it in a low gear and grind like mad, it'll get up hills so steep it hurts. Some so steep that the handlebars get uncomfortably close to the torso. Only one of the hills properly beat the bike, the other was walked voluntarily. McMahon's has nothing on Narrowneck for hills.
  • Stability through corners is, as previously noted, superb, but as expected, the fork travel obviously makes it behave very differently to my old hardtail, and some degree of front-wheel slide is actually quite tolerable, rather than suicidal. The stability actually allows big mistakes with reduced consequences. In other words, this time I didn't crash through the foliage screaming for my life.
  • Tear and fold a spare tube box, wedge calipers with four-layer card, transport problems solved.
  • Rear-wheel steering is very possible, in fact pleasant. Hop and kick the tail round with your feet as you change direction. Superb.



The Speedfox at the top of Glenraphael Drive, fresh from conquering Narrowneck with flying colours

The Speedfox at the top of Glenraphael Drive, fresh from conquering Narrowneck with flying colours



More observations after nearly four months in (May 2012)

  • The drivetrain gets dry and sandy very easily in Australian conditions. considering the idea of Chain Waxing (thanks @WeezMgk)
  • I've dropped the stem down two spacers, to its lowest setting, and the bike feels a little more confident and seems a little easier on climbs. Locking the suspension also helps vastly.
  • On removing the stem, I found the steerer tube was full of sand. Needs regular stripdowns, I suspect.
  • Now has a few more dents and scratches, one from the Wollemi NP ride all the way up the fork leg, another from a crash at Kanagra Boyd
  • As a result of dropping the stem down, my iPhone mount has been moved from stem to frame
  • Excessive tail rebound has been tweaked by playing with the damping settings on the shock. Now much more stable
  • Rear tyre completely worn out after well over 1000km. Needs new, considering moving to an asymmetric (narrowish 1.9 rear, fatter 2.1 front) setup like I used to run in the old days, or ~2.0 at both ends
    (currently 2.25). Brake pads wore out during or just after the Oaks on 27-5-12
  • I'm tending to get the pedals onto the ground a little more than I like, due in part to the bob of the suspension. Considering smaller pedals, stiffer suspension or some work on pedalling technique.

Here's the 2010 equivalent bike. In 2012, the model line was consolidated, and the SF03 became part of the re-jigged SF02 line - There's no direct equivalent any more, but a pick-and-mix of the three SF02 variants' componentry would get you a near equivalent.

Service Log

  • Stem dropped down May 2012 to accomodate faster XC position, smartphone bracket moved to frame. QR skewers swapped out for hex head skewers
  • Serviced in June 2012 by Favourite Cycles, Manly. New bottom bracket (XT replacement), new chain and cassette (DuraAce chain and XT equiv cassette), new brake pads, new rear tyre (WTB Weirwolf 2.1) - narrower rear tyre seemed to make the bike a little better handling, but the extra weight of a steel bead was noticeable.
  • Crashed fairly heavily June 30th 2012 on the Oaks Singletrack. Rear brake lever badly scarred, but other than that the bike survived. Main takeaway: large SPD pedals will be swapped out for smaller XT SPDs, to give a lower chance of ground impact.
  • Self-service July 1 2012 - Rear shock has been creaking for the last couple of rides and rear suspension has developed play. Disassembly of the rocker system shows that the top shock mounting point has some wear issues - the main bushings have worn unevenly and the shock itself may need replacement. For now it's been greased and reassembled and will be monitored closely. Slated to replace: Fox Float Rp23 (191mm). Also noted: frame seems to drain poorly, which may impact BB and headset - this is the probable reason the BB was swapped out at last service.
  • July 4th 2012 large SPD pedals swapped out for compact models.
  • Checked in with Echelon Sports, distributor of the Speedfox in Australia to check some specs. Seatpin size is 31.6, so a new post is arriving sometime soon. 191mm Shock length, 50mm stroke required for shock, so a Fox CTD or Float RP23 are being hunted.
  • July 11th 2012 in response to the weekend's riding, I've decided to pop some bar-ends on to see if it'll improve climbing by giving a more forward weight balance. I added my old X-Lite 90s-vintage bar ends, at < 100g per pair, and may swap them out for more modern stubbies if the experiment is a success.
  • July 15th 2012 - Saddle moved forward on rails to get a better climbing position, with the secondary effect of more neutral cornering. Changed position means front shocks feel a little different and may need adjustment. New position seems to work, with the second big climb of the Oaks firetrail going much more easily than before.
  • July 16th/17th 2012 - Replacement rear shock arrived and fitted (Fox Float RP23). New shock pump acquired and tuning commenced. Hope to get the new suspension tune sorted by the weekend. Tune too stiff on the morning commute, so some air dropped from both ends for quite a plush feel. New shock seems to have more sag than the old one, but a smoother action with lower rebound.
  • July 30th 2012 - Snapped a spoke on the rear wheel during the weekend's long ride to Yellomundee and back, replaced by the friendly staff of Atelier de Velo in Sydney. I now have one silver spoke among 31 black spokes, which I consider a badge of honour. If you don't break a spoke occasionally, you're not riding hard enough.
  • August 26 2012 - During a relaxed trip down to the Royal National Park, the seat tube snapped just above the rear shock cantilever mount. Luckily I was going at low speed when it happened, but it looks like it's the end for the frame. (27 Aug 2012 - has gone in to Favourite Cycles in Manly for assessment)

The broken seat tube

The broken seat tube

  Name Size
- Framebreak.JPG 518.07 KB
- speedfox75.JPG 113.04 KB

 

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