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  1. #1
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    Anyone put a longer fork on an Epic 29er?

    I have a 2011 Epic Carbon 29er w/ a Reba RLT fork and I'm considering modifying the fork from 100 to 120mm of travel (By changing internal spacers it can be set at 80/100/120.) Has anyone else tried this with a modified Reba or a different longer travel fork?

    I've had this bike for around 6mths and I still don't ride it as well as I should in technical XC sections and think the steep head angle, low h-bar position (currently running a -6 degree stem and flat bar,) and possibly "only" having 4" of travel could be a factor. This is my XC race bike, so I'm not looking to tun it into an AM bike or anything. I just want a little help going faster in rougher/steeper XC terrain and thought a longer fork might be just what I need.

    My trail bike is a Yeti 575 with a taller than stock 160mm F36 fork running a taller 27.5 front wheel, so I'm definitely used to a REALLY slack head angle. I'm not worried about experimenting and voiding the warranty, but it would be great to get some feedback from others before going to the effort of modding the fork. Does anyone have some first-hand experience riding an Epic w/ a taller than stock fork?

  2. #2
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    I have an '11 Comp with the spacer out. It's been out since before I got it, but I've ridden other similar 100 mm XC bikes and know what the change from 100 to 120 is like from Revelation turnkeys. Always ended up leaving those at 120 anyway!

    It's not like magically you can do stuff better with another 20mm. What I do like is that you can set maybe a bit more sag and have a longer and softer stroke. It took me a while to realize that the suggested retail pressures for my weight on the fork leg no longer apply. That's because the + and - chamber volumes end up different. So the suggested 110 psi - by the time the fork is compressed to 100mm - becomes probably about 130 psi and the fork needs a far heavier rider to ever use the last travel. So at 90 psi the travel is right but the thing is slack at the top out. Reducing the minus pressure to 75 - 80 psi fixed that. IOW you'll end up dropping the plus by about 20 lbs and the minus to 10 -15 psi below the plus to get similar setup to stock. That's what I found anyway.

    I can see how this sort of stuff would confuse those who have difficulties enough just getting their suspension in the ballpark as it is. So now they just have Solo Air and non adjustable travel spacers, which is simple and straightforward.

    All I can say about it is that there's nothing preventing you from taking the spacer out and seeing how you like it. You can always put it back in. And there was an Epic 29 Evo model in '11 that had the 120 fork so I don't think they'll void your warranty considering they did it first. Besides, it's not like Epics break anyway, from what I see, and you're only adding 4% more potential head tube loading - which drops to no difference once the fork is compressed.

    I was considering going back to 100mm until I found the sweet spot for pressures; now I'm happy to leave it at 120.

  3. #3
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    Hey ct, I was considering the same change for my epic because of the efficient but less than plush fork, which I am not a fan of, coming from trail riding background and longer travel bikes in past. But let me just say that I wanted a dropper seatpost more and put a ks lev on recently.
    I can't begin to tell you how this changed the ride and handling of the bike. I don't feel the harshness in the fork anymore since the saddle/center of gravity is lower most of the time on our rugged trails. I only leave it topped out on sustained steep climbs, which is not much here. Eventually, I will put a 120mm fork on but no rush now. Loving the ride more than ever. I will never ride any bike w/o a dropper post again. Just something to consider.
    I really agree with bulerias. I kept lowering my fork pressure till I got full travel with light top out several times every ride. Recommended pressure for my 155lb wt was 90-105 and I run 58, with 2.35 Nobby Nics at 19lbs pressure tubeless w Stan's. Gives a great ride w/o burping on our severely rocky/rooty trails. Rarely do I see another rider w susp. set up to give full travel. It's the most poorly understood concept for improving the ride.

  4. #4
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    Thanks for the feedback. Aside from the travel, I think I've got the fork fairly dialed in by this point. I started w/ 25% sag, equal +/- and no compression, but after a few rides moved to negative 10 psi less than positive and compression/lockout lever to around a 1/4 turn from full open. Those changes all helped, but it's a good reminder that I'll need to re-adjust the air pressures if I pull the spacer out for longer travel. It seems like I may as well give it a shot since it's free other than my time and a some fork oil and I can always change it back if I don't like it. I expect the slacker head angle, taller h-bar position, and addl travel will all help w/ minimal if any downside.

    After that the next potential step would likely be to look at burlier tires. I'm running RoRo frt and RaRa rear both setup tubeless. But a change there would likely add rolling resistance and rotating weight.

    And then finally a short travel dropper post might be the next step if needed. I'm running a 5" LEV on my trail bike and even though I won't be riding really steep/extreme terrain on the Epic, I definitely agree that being able to drop the seat a couple inches does help my cornering and descending. The only downsides there would be cost and weight.

    I'll try pulling the fork spacer this weekend as step 1, reassess, and then go from there. Thanks.

  5. #5
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    Just add from my experience, and my activity to create an Epic EVO--more on the 'trail' side of XC bikes:

    The Reverb I added has been a great add to my Comp Carbon. Gives me the confidence and ability to ride most anything I come across on a ride. Dropping the post increases the playfulness of the bike. I don't completely understand it, but I know the bike feels like a different ride with the push of a button. Its not like it becomes a full blown trail-destroyer, but I know it increases my confidence.

    I'm also mildly curious about upping fork travel. I've seen it posted online that you ca go up 10% in fork travel with no issues on warranty stuff, so 20mm should be ok. Personally, I'm think I'd like to try 110 and adjust the cockpit one of these days.

    Finally, I've got a wide, carbon wheelset on the way. Will be doing some experiments with tires. Up front I'm not concerned on width, but curious as to how big I can get in the back.

  6. #6
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    120mm fork

    I replaced the Rockshox SID Brain fork (set to 100mm travel) on my 2012 Epic Expert 29er with a Manitou Tower Pro 120mm fork. Unlike the Rockshox the Manitou offers easy custom tuning plus on-the-fly lock-out and low-speed compression adjustment with the upper switch. The Manitou also has 15mm thru axle and is significantly stiffer than the Rockshox.

    Happy with the result. The extra travel is nice and the overall ride is plusher. Had to add 10psi to the rear shock because is now seems more active. Despite the front coming up a bit and a slight slackening of the head tube angle the steering seems as sharp or sharper, likely due to the increased offset of the Manitou.


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