# Transform hardtail MTB into adventure bikepacking rig



## merzperson (Feb 2, 2012)

I've been dreaming of putting together an off road adventure bike for some time now. During a recent trip to a LBS the new (to me) Trek 920 caught my eye and I was really impressed by the design. I've always assumed I'd build my bike up with a rugged steel frame like the Salsa Fargo or even Co-Motion Divide, but the more I thought about it the more I liked the idea of having a much lighter setup that an aluminum frame would allow. I never throw around my gear and I'm confident that the strength and durability of steel is overkill for what I'd be using this bike for.

Then I realized I have an aluminum hardtail 29er that I could essentially transform into a Trek 920. The only thing I can't quite figure out is what fork I should get to replace the 100mm Reba. I've never set up a modern fully rigid mountain bike or even replaced a suspension fork on a mountain bike, so the concepts of suspension correction, axle to crown length, and offset are new to me. If I'm not planning on using the bike for any technical mountain biking, is it important to get the fork geometry corrected? So far I've looked at several steel and carbon options including various Surly forks, which tend to be very heavy but have plenty of braze-ons for carrying gear.

TL;DR - What fork should I buy to replace a 100mm suspension fork to turn my hardtail 29er into a lightweight adventure rig.

Any tips would be much appreciated!


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## vikb (Sep 7, 2008)

For GDR-esque riding nailing the stock geo on your bike is not critical. OTOH if you can find something close why not stick with that unless you are dissatisfied?

*Length/Offset*

- 100mm Reba has an a to c of something like 506mm which sagged is ~481mm.
- the Surly Krampus fork is ~483mm and the aftermarket version comes with all sorts of braze-ons if you need them.
- Whisky #9 carbon fork is 480mm
- Salsa Firestarter fork is 483mm and has braze-ons
- all these forks have offsets in the 45-47mm range
- Whisky and the carbon Firestarter require a tapered HT
- the Krampus and metal Firestarter work with any HT 1 1/8"+

*Weight*

- Krampus fork = 1100g [actual weight cut steerer]
- Whisky fork = 850g [actual weight cut steerer]
- Firestarter fork [steel]= 1219g [spec weight uncut]

All these forks would work. I'd decide if you need/want to carry stuff attached to the fork or not. The Whisky doesn't really allow that. The rest have braze-ons.

Personally I don't like stuff on my fork. It changes the steering feel, makes the bike wider and I tend to lean/lay my bike down in ways that damage stuff carried there.

Instead if I need more water I'll attach a 1.5L bottle/cage under the DT where it affects handling least and keeps the bike narrow and doesn't get bumped/bashed into things.


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## big_papa_nuts (Mar 29, 2010)

Keep in kind cockpit length if your considering converting to drop bars (like the 920 has). Bikes designed for drop bars have much shorter top tubes then those designed for MTB bars.


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## merzperson (Feb 2, 2012)

Thank you both for your very helpful replies. I should have specified that I'm limited to 1 1/8" straight steerer forks which limits my options for carbon. The Krampus fork with braze ons seems like a great option although still pretty heavy. Luckily I have a long torso so I'm not worried about the longer reach achieved by adding drop bars. I'll just get a steeper/shorter stem and stick with compact drops.


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## evdog (Mar 18, 2007)

If your Reba has a lockout I would give it a try before buying a new fork. Having front suspension available could be beneficial for some trails or roads even if they are not technical. I often lock out the Revelation on my hardtail when bikepacking. You might save a little weight with a rigid fork but air forks are still pretty light these days, and by the time you are loaded down with gear the difference won't be very noticeable.


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## She&I (Jan 4, 2010)

The crux of it, to my thinking, is what kind of riding you plan to do. "Adventure" is a broad umbrella; nearly meaningless, really. With the drop bar comment I assume a glorified gravel grinder is what you're building. 

In any case, my first thought is essentially what evdog wrote. As with a trail bike, one decides where she wants the performance advantages. Owning both a rigid and squish fork is the best option for a normal sized tire bike IMO. With an easy swap you have a very different tool. You may as well at least run your squish fork to get some reference before ponying up for a rigid. Even if not on "tech" terrain, a little squish up from can make a big dif at day's (or week's, or month's) end.

Have fun...


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## flying 1960 (Aug 12, 2008)

I like my Carver carbon fork on my Nimble 9 hard tail. I am light at 145 lbs and I never see it flex. Rode 250-300 miles in Idaho last month (trying to avoid smoke) lots of washboard on the fire roads. Running 2.2" Kenda Honey Badgers mounted tubeless with about 20 psi took out most of the sting.


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## stremf (Dec 7, 2012)

She&I said:


> ...You may as well at least run your squish fork to get some reference before ponying up for a rigid. Even if not on "tech" terrain, a little squish up from can make a big dif at day's (or week's, or month's) end.
> 
> Have fun...


Plenty of folks use suspension forks, and even full suspension rigs for bike packing. I, too, would suggest just heading out as-is. Stuff a sleeping bag, tent and food in a backpack and head out. No need to spend money now, if you end up hating it.


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## BLUFF (Dec 23, 2013)

You didn't specify what dropout the Reba has, I'm assuming 15mm in which case this will severely limit your rigid fork options. Any way as others here have said just lock it out and enjoy the ride.


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## GSPChilliwack (Jul 30, 2013)

BLUFF said:


> You didn't specify what dropout the Reba has, I'm assuming 15mm in which case this will severely limit your rigid fork options. Any way as others here have said just lock it out and enjoy the ride.


If the front hub is 15mm, it's easy to use an adapter to run the same wheelset with a 9mm qr fork.


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## merzperson (Feb 2, 2012)

I'm not interested in running my Reba, which is why I started this thread. I love climbing but HATE climbing with a squishy fork. The Reba doesn't fully lock out, and being 190lbs it's unbearably squishy no matter what I do. Also it's super heavy. I have a steel 700c adventure touring bike that's great, fits up to 29x2.2's, but I wanted to turn my hardtail into something lighter and more rugged.

That said I've put this project on hold as I'm getting ready to ride from my house in Portland to South America starting next month. Thanks for all the suggestions, everybody.


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## Lewy (Aug 23, 2009)

Just in case you're still checking this thread.

This is my 2012 Trek Superfly with Krampus fork. It works really good and I love it.


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## hoogie (Jun 26, 2009)

I picked up an old giant yukon 26" rigid mtb really cheap at a garage sale some years ago ... I pulled it to bits and rebuilt it as a touring bike ... being old school, it has a steel frame and reasonably long chainstays, so the ride is stable and comfy
the gear isn't too flashy but is still robust enough for touring, and if it gets stolen then I haven't lost too much money on it ...
I also have a 1998 trek 520 touring bike and built up an ogre frameset this year ...


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