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LiViD GV-2B Chainguide
Reviewed by Mark Mayo |
Spring is here, and the opening of the Whistler bike park is just around the corner. Ah yes... fond memories of railing down A-line... tweaking it out on every air... looking for just a little more speed... While I spend most of my time nervously nudging my way down the steeps and skinnies of the Shore, there's no denying the ear-to-ear grin after a run in the bike park. For those who haven't tasted Whistler in the summer yet, I have only one (OK, four) word(s) for you: pee-your-pants-fun.
Whistler is a place where non-downhillers like myself ratchet the speed dial up a good many notches past our normal comfort setting. Ask anyone who's ridden Whistler - before you know it you're doing mach 2. It's also the only place I've ever biked where I loose my chain three times a day. There's nothing like popping the chain on the last corner of the bikercross course and finding out about it as you stand on the pedal to crank towards the last table. *splat*
The fact that my best days on Whistler have been without a chain says a lot about the troubles I've had keeping the chainline functional at speed. The two-bashguard setup on the trusty Bullit has rarely let me down riding the Shore, but my chainline was throwing temper tantrums at places like Whistler and Pemberton. After a particularly nasty bitching session with the nsmb crew, Allan from LiVid Components knocked at my door and, like a stork delivering its precious newborn, handed me one of the first LiVid guides to see production. First impressions are worth a lot in this business, and LiVid's baby certainly impresses: the carbon fibre swing arms and polished bashguard are downright sexy.
For the uninitiated, a chainguide is simply a device that attempts to "guide" your chain on the front ring to prevent it from popping off. The most common approach is to only run one chain ring up front (the granny ring is for wimps!) and wedge the chain between two rings or bashguards. The GV-2B uses this technique, and provides a way of attaching two rotating pulley wheels above and below the rings that really do wonders in preventing chain slap from bouncing the chain right off the front ring. MRP pioneered this type of setup, and you've probably seen a MRP chainguide on a buddy's downhill rig.
What separates the LiViD from everyone else's guide is that the swingarm that holds the little pulley wheels is made from two rotating carbon fibre plates instead of a single metal plate. The biggest complaint from many owners of traditional one-piece guides is that they can never get the pulleys positioned exactly where they should be. With the LiViD, each arm can be rotated and positioned independently - the result is a guide that can be set up nearly perfectly on a wide range of bikes. I'm not going to give you pages upon pages of explanations of how carbon fibre stuff works and why it's a great choice for a chainguide. Instead, I suggest you go to LiViD's Web site, and read all about carbon fibre yourself. The basic idea is pretty simple: carbon fibre composites can be made to be very rigid when force is applied in one direction, and flexible when force is applied in another. Which brings us to the second complaint of the folks who own metal-swingarm chainguides: one good smack to the side of the arm and it gets bent. A few smacks and unbendings later, it snaps completely. With the LiViD guide, the arm is insanely rigid vertically, but flexes side to side. Press it in from the side and it bends, release your thumb and it snaps rights back into place. Brilliant.
So how does it work in The Real World™? The test bike is a 2001 Santa Cruz Bullit, size large, with its notoriously difficult chainline that's beaten down many a guide in the past. Just to be particularly hellish on LiViD's miracle guide, I decided I would run the smallest chainring allowed (32T) and I added a couple links to the chain to make sure we really truly had the worst possible test case. Installing the bashguard and guide ring on the crank spider was easy as pie. Follow the diagram that comes with the GV-2B and you'll have that done in 15 minutes.
Installation of the plates is simple in theory: you basically take out the bottom bracket and wedge a mounting bracket between the drive-side BB cup and the BB shell. To this adapter you fasten the carbon plates. Installation in reality turned out to be non-trivial. The very aspect of the LiViD system that sets it apart was also a liability in my case: because you have to fit two plates to the adapter bracket, the mounting hardware is quite a bit thicker than a conventional guide. I simply didn't have enough clearance between the mounting tabs and the crank spider. After some phone calls with LiViD and some mucking about with different sized spindles and spacers, I determined the guide simply wouldn't fit. At this point, Allan was scratching his head as he had a dozen reports from various riders with the same setup as me (68mm BB shell, Race Face North Shore cranks). Why doesn't my Bullit "just work"? I dunno, but it didn't.
Allan's solution was pretty simple: reverse the bolts to effectively make the setup thinner. This trick applied to the 118mm spindle I had been using with another guide gave me enough clearance. The chainline certainly wasn't perfect, but it was acceptable. If your frame has ISCG tabs, you won't need to mess around with the mounting bracket and you'll have the guide installed in 10 minutes. The fact that almost none of the "freeride" frames have ISCG tabs welded on sucks ass. Get your acts together Santa Cruz, Norco, and everyone else. I shouldn't have to spend a frustrating night dicking around with spacers and bottom brackets to get my swank chainguide installed - frames should be designed with chainguides in mind from the start.
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| Doing my best to shake the chain loose. Photo: Cam McRae |
Once you get the guide on, which to be fair is very straightforward for 95 per cent of the frames out there, you're in for a treat. The guide is light, works like a charm, and is damned near indestructible. I've had the GV-2B on for six months of solid riding, and it's basicaly performed flawlessly. Not one chain pop. That's what a good chainguide is all about. I've cased some hops over logs and smacked the bottom guide plate hard and the worst that's happened is that the plates rotated the adapter bracket forward a bit. A bit of elbow grease on the trail and it was back in place. On one occasion I picked the bike up in the trees after a crash to find it resting on its side with the full weight of the bike on the pulley wheel! The weight had the plate bent in a good 2cm under the pressure, but as soon as I picked the bike up it snapped back in line - no damage to the plates. The carbon fibre, it seems, lives up to LiViD's claims.
Out of 6 months of riding, I've only had one problem, and that's with the Lexan tabs that fit into the swingarm plates to hold the pulley wheels. I've snapped a few of the bottom tabs slipping off skinnies and catching the pulley wheel as the rear wheel unexpectedly slides down. The Lexan tab just blows apart sending the pulley wheel flying. LiViD will replace any that break for free, and are working on some new sturdier tabs just for us sloppy riders who like to fall off the back of skinnies.
Overall, I think the LiViD is one of the best chainguides out there. It's certainly the best I've ever used, and if the nsmb Product Reviews and Bulletin Board testimonials are anything to go by, I'm not the only guy out there that thinks so. The GV-2B isn't perfect - it's possible that the guide may not fit your bike. Nevertheless, it fits on more bikes than any of its competitors. The Lexan pulley tabs can break - but you get spares in the kit, and if you run out LiViD will give you more for free, and will likely have carbon resin tabs out by the time you read this review. The guide makes no noise when pedalling, adds no resistance, keeps the chain in place, and can take a few knocks. In short, it works.
If you're in the market for a guide, my recommendation is to give LiViD a call and give them your frame specifics. They'll tell you up front if the guide has been tested on your bike already, and can give you some tips on the install. Personally, I'm not giving my GV-2B back... and given LiViD's track record for durability so far, I suspect the old Bullit frame will snap before the guide plates do.
To reach LiViD, just visit the LiViD Web site.
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