Gamut Dual Ring Chain guide: Long Term test.
Madison are the U.K Disty for Gamut, click here to see more. Many thanks to them for flowing the Gamut P30 Dual to show you Pinkbike readers.
Imagine the scene: You’ve just grunted your big all mountain/trail rig to the top of your local trail. You’ve sweated and pedalled for over an hour, winching away in the granny ring to wind that big 160mm (6”) rig to the point where all that travel is going to pay for it self. It certainly wasn’t helping on the way up, but it sure as hell is going to help now. You slip on your goggles knowing that this is where the fun begins. Tech trails and big drops. Flow, this is what you came for.
Three turns later and you’re cursing, you look down and your chain is wrapped round the bottom bracket, gutted. Time to stop turn the bike over and get those nice new gloves oily as you try to re route the chain which somehow has managed to lodge itself deep in the recess of the frame and chainset. Flow now utterly destroyed. Mood worsened.
One thing that Downhill racers have always known is that chain security is a key consideration if you want to be sure about getting the bottom of the hill fast. No one would ever think about building a DH rig up without a chainguide. Longer travel means more chain movement and that in turn increases the chances of a chain snarl up. Whilst it is common to see more technical trail riders using a double and bash set up it has been less common to see these types of rider running a chainguide. However over recent years it seems that All mountain and trail riders are catching up and looking at ways of making sure their hard earned plummet time is not spoiled by an errant chain. Increasingly frame designers are including ISCG tabs on their trail designs rather than just the gravity bikes. (For example Orange have recently bit the bullet and included ISCG tabs on their 2011 Five model) It’s all about controlling the controllable.
In the last few seasons chain device makers have been tapping in to this by developing and marketing dual chainring devices that increase chain security for those wanting to run more than one chainring. With this in mind I have been testing Gamut’s offering for the last 6 months on both DH tracks, XC loops and even some Welsh mountain trail centres.
First Impressions-
Upon opening the box you get the feel of a quality product. The boomerang is a nicely anodized red colour on the test model and my fears about a polycarbonate bash ring feeling plastic like and cheap were unfounded. The bash ring has a high gloss finish that makes it look the business. The next thing you notice is weight, or rather lack of it. With the Bash guard weighing 83g and the boomerang and roller weighing 72g it’s right on the money weight wise. The device has a total system weight with all hardware of 163g. It’s definitely not going to hold you back and it was certainly noticeably lighter than the Race Face all mountain guide it replaced(245g). The metal bashring and added top guide pushing the Race Face device behind in the weight stakes. Good Start.
The test model was an ISCG model, so it was lashed to the faithful '08 SX trail for the period of the test. Fitting was easy. No filing, no fiddling and very little issue in lining everything up. No mean feat considering the asymmetric swing arm and large linkage around the bottom bracket on the SX Trail. Instructions were also clear. Top Marks Gamut.
One thing to note was that after fitting I ran the bike through the gears on the work stand and the roller managed to wind itself off. A 2 minute refit with some blue loctite on the grub screw and she was good. Two days later I received an unsolicited email from Gamut telling me to add loctite to the small grubscrew before fitting, so they clearly knew that they had the issue and hopefully have addressed it.
Riding impressions-
In the 6 months since this device has been fitted it has performed almost faultlessly. One generic problem with all dual devices is the lack of chain retention around the front mech. This can result in any slack in the chain being passed through the mech cage and allow the chain to fall off the large chain ring on the granny ring. This usually happens on big bottom outs when rear wheel travel is at its greatest creating chain slack. The Race Face device did this a lot. The Gamut device has done it twice in 6 months and both after big compressions. It definitely feels more secure. The chain has never once come off to the point where it was jammed or I was unable to pedal. On the two occasions where it did fall, a quick push of the shifter was all that was required to get her in place again.
The chain device is quiet in operation; the nylon roller makes no sound and does not feel like it is dragging the chain at all. The device has been subjected to the liberal use of the dirtworker and the roller is still running sweet. Top marks for that!
Finally, the polycarbonate bash ring still looks good after 6 months of abuse which cannot be bad at all. I also found the glossy finish helps the device to shed mud quickly.
Summary-
There are a few things to put you off fitting a chain device to a bike with more than one chainring. Weight, noise and mud clearance all cause problems as well as the challenges of running one with a front mech. The Gamut faces these problems and delivers. At £99.99 it is certainly not cheap, but it is of good quality and performs. The device comes highly recommended, no ifs, no buts. In fact it performs that well that I think I’m going to order a bottom bracket mounted version to slap on my more XC orientated Heckler!
-Chris
Stay Unclipped!
Si Paton..
Descent-Gear.com 2010 Fox/Monster Energy Beanies Instock 24.99 Posted
Never had this happen on my e.13 drs mounted on 3 different suspension designs...seems like this is a user setup error with the front der.
I've owned 3 different E13 DRS on 3 different bikes and they have all had this issue - the worst was a trip to Whistler in 2007 where it dumped the chain 3 times, 1 of these was jammed so bad I had to remove the cranks at the bottom of the bike park to get it cleared
I'm a pro bike mechanic who installs alot of chain devices both single and dual ring, before you blame bad setup...
solution.. become a real man and ride single ring