Google this. I have seen a santa cruz v10 modified for trail bike use. Well, enduro use.

Measure the bb width. DH bike might have wider q factor. Crank might or might not fit. How about just change the chainring to a 32?

 

I mean you can ride anything anywhere if you have the gearing and legs for it.
I rode my Big Hit everywhere with a double ring.
But it will be the seat post angle that will be annoying, if you can fit a dropper post it will be pretty slack.
But if you have trail tyres and the will then sure.

 

I like the challenge of trying to convert it. It has a relatively high bottom bracket so replace the fork with a single crown should be fine (my rough calculation puts the bottom bracket height going from 342 -> 332 with a 160mm fork) so still in a reasonable height. Also, a 40mm lower fork should steepen the head angle around 2 degrees, putting it right in line with today's trail bikes.
The seat angle is pretty slack, so with a dropper that will likely be annoying.
Looks like that bike has a bb30, so you'll likely need a bottom bracket to use your XTR cranks (bb30 -> shimano). The stock crankset is heavy, but you could probably just use it if you want.

Just as an exercise, if someone gave me this bike, I would spend around $500 to make it as trail worthy as I could:
New Tires, Butcher DH are overkill for trail riding and lighter tires will dramatically change this bike: $80 for 27.5x2.6 specialized eliminators (-1.8lbs)
New Fork, The boxxer is a premium fork and incredibly good at what it was built for, but it is heavy and not needed for trail riding: DVO diamond 170mm (or something close) $350 (-1.5-1.9 lbs)
Drivetrain, you have the XTR, put it on. Get adapter bottom bracket for bb30 to shimano ($80) (-1.5lbs)
get rid of chain guide (no need with xtr drivetrain and trail riding)
Those changes in themselves should get the bike down to around 32-33 lbs, which will make it more rideable. But what about the 200mm of plush travel? That may make it difficult to pedal, but at least you'll be riding on a newer bike than your giant.

 

STA and low AS will be awful to pedal. Like so bad.

Honestly, I'd recommend selling it to fund another more suitable bike, or just saving it for the occasional bike park trip.

 

You have to make sure components are available with the right standards. DH bikes typically uses wider hubs and BB (maybe not the demo tho), that would be the main issue. Derailleur cage may need more range than usual (=smaller cassette) if you keep all the travel.
Then there is geometry. angles will be slacker than ideal, and you may or may not be able to correct it by putting a smaller fork and shock with extra yoke.

I've seen mondrakers DH bikes converted to enduro bikes, but their starting geometry was ok to begin with.

 

You have to make sure components are available with the right standards. DH bikes typically uses wider hubs and BB (maybe not the demo tho), that would be the main issue.

Good point. Probably has a 20mm front hub, so that means a new wheel as well as a new fork.
Honestly I'd leave as much as you can, lighter tyres and a bigger cassette and ride it for as long as you can. I wouldn't get worried about suspension kinematics, you're gonna be pedaling a DH bike.

 

another vote for selling to fund a Trailbike which you will appreciate far more, especially on the uphills

 

Can't imagine this would be a worthwhile endeavor, but who knows. I guess the question is what's the market for a DH bike, used, near you? Where I live, I couldn't give that thing away, but in other places of course, they'd be sellable.

 

I use to pedal a variety of DH bikes uphill, it's no big problem. Back then, the biggest cassettes were 32 and 34, so to pedal the DH bike, which often had a bigger front chainring, you stood and pedaled...like a SS. You get used to it.

Now, with dropper posts, 30t rings and 50t cassettes, not nearly the issue it was before. It'll still suck uphill, but it won't suck as bad and again, you get used to it. Personally, I wouldn't take it too far from DH land, like AM rims, EXO type casing tires for general trail riding, but I'd keep the widths of both and not concentrate on trying to dump a bunch of weight. I'd just concentrate on a good dropper post that will work, getting a decent drivetrain together with the necessary range.

 

I use to pedal a variety of DH bikes uphill, it's no big problem. Back then, the biggest cassettes were 32 and 34, so to pedal the DH bike, which often had a bigger front chainring, you stood and pedaled...like a SS. You get used to it.

Plus the factor of still pedaling when other dude is mountain bike walking, has to put some wind in the sails?

 

Thanks everyone for your input, it is appreciated.

 

Your biggest struggle will be with pedal efficiency. If you can't improve that it will always be an effort to climb or even coast on flat roads. Nice that the bike is quite light already. For that you have 2 key points:
Tires-> move to tires that better suite the places you will ride and with harder compound and trail casing. Schwalbe speedgrip/soft or Maxxis double compound for example. It will also lower the weight.
Suspension efficiency-> Increase the pro pedal/ compression to prevent high losses when pedaling. Contrary to much believe, lowering the sag will not give much improvement.

After that go for a ride and test if the bike is acceptable. If that doesn't dramatically improve the efficiency then I would say it is a lost cause.
If you are successful, feel free to spend time installing the XTR equipment on the bike. Biggest improvement will be by far having a big cassette on the rear.

In my opinion I would not focus too much on the wheels. From the overall bike weight, I expect the wheel to already be "light" for a downhill rig. Maybe move to a dropper post or get an used fork to make the bike more agile.

 

Your biggest struggle will be with pedal efficiency.

From doing this, I disagree. Maybe you mean travel, but 200mm is going to be soggy, no matter how "efficient" the suspension, but travel and weight are the big ones IME.

Also IMO, lockouts and the like make very little difference in time. Pedal w/o them and you won't miss them. I think these are used way too much as a crutch...that doesn't actually shave any significant time. For XC races at the highest levels, being 10s faster/lap or over 500' vertical climb is huge...but for someone out pedaling for 3hrs, it's not and I've never found a big benefit outside of that. It's a "feel" thing IMO like high engagement hubs, absolutely not needed, doesn't make you faster, but some people like the "feel", so they have a market, just not performance enhancing.

 

Could post it 'for trade for size X trail bike' on FB marketplace and see what happens?