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So I was looking at this frame: https://www.cyclingdeal.com.au/buy/gt-fury-alloy-2.0-mountain-bike-bicycle-cycling-fr/FR-GT-005-PP And this fork: https://www.cyclingdeal.com.au/buy/manitou-markhor-mtb-mountain-bike-fork-26-travel-1/FK-MT-MR-PP Will they work with eachother? I don't really want a downhill bike, just a trail one. Besides, as a minor I feel like it would make the bike harder to get on. I am buying this myself, (50/50) with parents, so I don't want to waste money.

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That frame is designed for 26” wheels. That fork is designed for 27.5” wheels so would not be a good choice for the frame for that reason.

The manufacturer specified 200mm of travel for the production bike in 2013. Trail forks top out at about 160mm travel. So no, you can’t use a trail fork with that frame.

If you want a trail bike buy a trail bike frame suitable for modern wheel standards like 27.5” or 29”. A DH frame is heavy and built to go downhill fast and uphill not very well. The GT frame is cheap but not what you’re looking for.

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    Combining a 26" frame with 27.5" front wheel is actually not at all an unreasonable thing to do. The geometry will of course change, but a) there's no such thing as right or wrong geometry b) if the new fork is shorter then this will offset the bigger wheel. The problems with this idea lie elsewhere. Jan 1, 2022 at 21:42
  • @leftaroundabout Ride a bike with bad geometry. The bike won’t feel right and is unpleasant to ride. Is the geometry still right in that case? Besides, playing experimental bike building is probably out of scope for the OP. Jan 1, 2022 at 23:34
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    it will feel different. Of course. But that's the whole point of having different bikes for different applications. You could say a DH bike has “wrong” geometry to begin with – it's a geometry that will never feel right for climbing. Putting on a shorter fork will make it less slack, in a sense “less wrong” if the purpose is trail riding... except, it won't do that job well anyway, but as I said the reason can't really be reduced to geometry. Jan 2, 2022 at 0:03
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The short answer is you can. While the bike is designed for a 200mm travel, a trail fork with the same axle/crown as the bike is designed for will give the same geometry. Check the axle-crown of this fork against the frame specs (You may be better off with a 29er fork, or run a mullet (Bigger front wheel than rear). Even if the geometry is out, the bike is still rideable, it not going to handle as the frame designer planned.

However I would not recommend it. The frame is not build for the purpose you are after, by the time you have acquired a rear shock, forks, wheels, drive train and other components, you will probably be spending more than buying an assembled bike with similar trail performance.

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By "trail fork" I'm assuming you mean any single crown fork. Enduro and Downhill bikes have become interchangeable over the past few years so there are a number of single crown forks that can now be used on downhill bikes. Rockshock's Zeb tops out at 190mm, Lyric at 180mm and Fox's 38 tops out at 180mm.

However this frame was designed for use with a dual-crown 200mm downhill fork, the fork you have linked has 100mm-120mm travel and is designed for an XC or trail-lite bike. It wouldn't work on this bike even if you were willing to run it as a 27.5"/26" mullet, you'd still be missing at least 80mm of the front height.

There's a number of other reasons why this wouldn't be a wise purchase, mainly because of the huge changes in standards and geometry that have happened since the frame was available. You will struggle to get many decent parts to fit it (even decent 26" tires are a struggle) and it could easily become a money hole. Finding a shock alone could be a nightmare.

IMO, if money is an issue, you're better off looking for a newer second hand bike that has modern featurs such as boost, thru-axles, 27.5" or 29", dropper post, 1x drivetrain and a few more not on the tip of my tounge.

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If you “don't really want a downhill bike” then you shouldn't buy a downhill frame, simple as that. Although the double-crown fork may be the most visually striking difference compared to a trail or enduro bike, the more important issue is that the frame just isn't designed for efficient climbing at all.

  • Of course, the standard gear selection for downhill bikes is hopelessly inadequate for any climbing. You'd definitely need to use a bigger cassette, which would probably work ok but don't be surprised if you run into issues if there's not enough space somewhere.
  • There isn't really any thought given to bob prevention. Now, that can be ok as long as you only winch up in a low gear in the saddle, however...
  • The frame is meant to be used with a short fixed seatpost. That's fine for descending, but it means climbing is basically impossible without standing up. And out of the saddle, the bobbing does get very annoying.
    Because of the short seat tube that doesn't reach down to the BB, you also can't really install a long post. Well, you could, but then you can never slam it down without getting in the shock's way, and descending with an extended seat just sucks.
    Even if you can fit a proper dropper post to the bike, which I'd definitely recommend, then there'll be lots of compromises. You won't get as much travel as would be possible in a bike intended for a dropper, and the slack angle means the saddle will either be too far back in the extended position (which makes climbing even more sluggish) or to far to the front in dropped position (which is bad for leg control).

Global Mountain Bike Network did a video on how a downhill bike can be converted to be usable for enduro. It kind of worked, but they didn't even consider replacing the fork with a single-crown one.

I think the fork really is the least of problems. In fact, I'd say fitting a downhill fork to a trail bike can kind of make sense to make it more downhill-suitable, but the other way around you just get the worst of both worlds. A shorter fork on a downhill bike would also steepen the entire geometry, but I doubt that would make it much more climb-friendly. The low BB would mean you constantly get pedal strikes, and the heavy frame would really get the small fork in trouble on the descents.

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  • While the frame won't be designed to in any way minimize bob (unlike a trail bike), the correct rear shock selection and tuning will sort out most (but not all) of the bob problems.
    – mattnz
    Jan 2, 2022 at 0:43

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