Rich: Holy moly, have I got a video for you today. We are going to be answering a question
that gets asked an awful lot here at GMBN Tech, and that is, how much fork is too much
fork. Can you over-fork a bike? [music]
For this experiment then, we're going to need, it's going to have to be a hardtail, it's
got to be affordable, and it's going to have to have a monster fork on the front. What
if we got knocking around? No, no, no. Yes. Male Speaker 2: [whistles] It's over there.
Rich: What the-- Look at the state of that thing. Whoa.
Wow, this is one wild-looking machine. I'm pretty sure it's not sold with 190 mil lyric
on the front as standard. Let's take a closer look at this trusty steed.
I've got here a 2019 Grand Canyon AL 4.0. This bike is normally spec'd with 100 mil
travel cross-country fork. It's exactly the kind of bike that we get asked if it's okay
to put a longer travel fork on. That's what we've gone and done. We've put 180 mil lyric
upfront on this size, large beauty. Let's see how the bike can handle it. Now, time
for a quick serious bit, I should say that Canyon do not recommend putting a fork of
this travel on this bike. It will ruin the ride quality and avoid any kind of warranty
that you have with them. Anyway, enough of the series, but this is a tech video after
all. Let's have a look at some of the numbers. The bike in its original, guys, has a head
angle of 70 degrees, a bottom bracket height of 305 millimeters, wheelbase of 1,119 mil,
bar height of 1042 mil, and a seat tube angle of 73 degrees. Now, let's take a look at it
with these monsters on the front. The head angle has become 64 degrees, bottom bracket
height, that's now at 327 millimeters, whilst the wheelbase has grown to 1,200 mil, bar
height has gone up to 1,100 millimeters, and the seat tube angle is positively slack 68
degrees. Crikey, those are some pretty big number differences,
most noticeably the 64-degree head angle the bike now has, which is actually comparable
to a lot of modern-day enduro bikes. Obviously, the other number differences have grown. Now,
while 64-degree head angle may seem appealing, given modern-day geometry, it's actually had
a far more detrimental effect on the rest of the bike, but having said that, there's
only one way to find out, and I think it's about time we took it for a spin.
I'll be honest, I'm a little bit apprehensive riding this thing as no doubt there's going
to be a few pluses and minuses to riding a bike with such a fork on, but there is only
one way to find out, and let's start with some uphill. Front end comes up nice at least.
We are coming up to some steepness and-- Oh my God. I am now at the point where I need
to keep so much weight forwards that I've got no grip on the back. Definitely a big
negative, Holy Lord. Oh, we're getting there. Wowzers trousers. We've made it. Let's conclude
on ascending then, because there are some big statements to be made it. A fork of this
size on this bike has absolutely written off what it's like to climb.
The front end is so high that you're using so much more upper body to keep your body
weight over the front, but because you're doing this, the back wheel is just spinning,
it's got no traction, it's got a grip on it. You also find that if you were to need to
stand up well, goodbye any grip on the rear at all really. The seat tube angle obviously,
again, thrown off if you are sitting down. It's sliding so far back your bums all over
the show. Yes, definitely a thumbs down on the ascending. We've done the ascending, the
climbing is finished Thank God, because I'll be honest, it was an horrible experience for
obvious reasons, like I've said. I'm glad we don't have to do that anymore. It's time
to descend. Hopefully, this thing can turn it around.
We've got slack head angle. We've got a longer wheelbase. I love to go downhill. Let's hope
this loves to go downhill. Then we need to make one alteration. That is the seat post
is way too high. Let's just slam that thing out of the way.
There we go. Male Speaker 2: Slam it, Rich.
Rich: It's slammed. I'll do that. [laughs] That's what we're working with. There we go.
That'll do me nicely. Let's go. Oh my Lord. Oh my Lord. [unintelligible 00:05:44] Oh my
God. An immediate problem is that with it being
slacker and a bit more sturdy, pick up more speed, which is good. The budget breaks,and
you can't slow down. Oh my God. Oh my God. Oh, wow. Descending,
completed it, mate. Interestingly then, there were more pros, I'll give it to you, on the
over-forking when going downhill, but downhill only at the moment. The longer wheelbase,
the slacker head angle did improve handling and obviously the higher front end meant on
the steeper stuff, it actually worked quite in my favor too.
The negative, however, just to play devil's advocate, is that with the extra speed you
gain and the confidence you have, the stock brakes on this bike weren't actually up to
the task of slowing me down enough. Again, a knock-on effect of the over-forking there.
If you're going to beef up the front and make things faster, if you ain't got the right
anchors on to slow you down, then you're potentially putting yourself at a bit of risk there as
well. That wasn't as bad as I was expecting. It's
time to put this bike through something a little more indicative of what it's made for
than a trail ride. I'm going to head out for about an hour and see what this thing is like
in its natural habitat. Pop up. [exhales] That's a wrap then. Just finished
on my hour trail ride. Like I said, something that this bike would normally do. You know
what? An actual pleasant surprise on my face. It wasn't quite as horrendous or pig-like
as I was expecting. The raked out head angle did make it slightly more fun. I was standing
up a lot of the time. The seat angle didn't come into play quite as much as well. Actually,
on a piece of single track, it was fairly fun still.
The added travel did absorb those bumps and just meant that you could have a little bit
more fun, a bit more care free on it. Actually, on the halfway ground between ascending and
descending, not too bad at all. I'm still thinking 180 might be a bit too much though.
Let's find somewhere to have a little perch down and go through what we thought of today
then. That's it then. I have ridden this bike today on a variety of different terrains,
up and down hill, and I can safely say it is well and truly over-forked.
The difference between this and with a stock fork is clear as night and day. Does this
mean you should over-fork your bike or not? Yes and no. A lot of manufacturers do actually
put a longer travel fork on the front of their bike. Generally speaking, the frames are designed
to take this, so the geometry and the characteristics of the bike have been adjusted accordingly.
On a hardtail like this, you certainly could up the travel ever so slightly on the front.
Maybe a 120 or max of 130 mil fork. Like I said, you've got to check with the frame manufacturer
first. Anything over that and I think you really do negate any positives from a bigger
travel fork, throwing out things like bottom bracket height, clipping pedals as I did.
[laughs] Wow. Seat tube angle and ride characteristics. It's just, they get altered too much. I should
just reiterate, I'm afraid, a serious bit. If you are going to over-fork or change the
fork on your bike, do check with the manufacturer first that, one, it's safe to do so and, secondly,
that it isn't going to affect the warranty on that bike.
That's enough. No more seriousness, I promise. We're done. Speaking of done, that's it, that's
the end of the video. Thank you very much for watching. I hope you found this really
interesting as I found it really interesting to ride today.
If you want to see more tech, then please subscribe. Thumbs up for this video if you've
liked it. Catch you next time on Tech. Cheers, guys.