- How does geometry effect an E mountain bike?
Well maybe a better way of thinking about it
is how does geometry effect you,
when you're riding your E mountain bike?
Because geometry has an impact in may ways
on such things as agility, comfort, control, fatigue
which is a big one and then stability
and weight distribution.
Now clearly all or some of those factors
are going to to have a big impact
in how much fun you have on your E mountain bike.
(upbeat music)
But is it just about the geometry?
Well absolutely not,
an E mountain bike should be a system
not just a collection of parts and angles.
There's many things to consider
such as the suspension design because that effects
such things as the stability and the agility of the bike.
The battery placement will have an effect
on the weight distribution
and of course you need to get the sizing right,
it's pointless having amazing geometry and angles
if you get the sizing wrong
because that is going to have a huge, huge impact.
(dirt and grass crunching)
Is there such a thing then as E bikes specific geometry?
Well yes there is to a degree,
but we'll come to that a little bit later.
First of all, if we compare traditional mountain bikes
to E mountain bikes in terms of geometry
well, they do seem to have been on a similar trajectory,
over the last decade
and that's unsurprising because, lets face it
mountain bikers and product managers
do tend to copy each other,
harsh, I know, but true.
But are we looking at a best E bike geometry
or are we talking,
just simply a different E bike geometry
because there is a big difference,
however one thing is for sure
and I mentioned this earlier
what you do have to get right is, fit and sizing.
(upbeat relaxing music)
Now sizing is fixed once you have bought
your E mountain bike,
there is absolutely nothing you can do
to change the frame size, job done.
But the question is then,
do you trust a brand's recommendations,
or maybe if you're buying from a shop,
do you trust a shop owner's recommendations
when it comes to size?
Well personally I don't,
now I'm six foot and Canyon recommend on their website,
that I ride a size large.
However, I find for the best mix of stability
and agility is for me to run an extra large.
However, I can ride both sizes,
now to confuse things,
if you have a look at a comparison between say,
a Specialized Levo and a Kenevo in size large
and S4, you'll find the geometry
and sizing radically different.
The good news though folks,
is while sizing is fixed you can still
change the fit of your E mountain bike
by swapping such parts as the handle bar,
the widths and the height, the stem, long or short
and of course the position of the seat in the rails,
and by doing that you will actually
expand or contract the cockpit of your E mountain bike.
(upbeat music)
Time then, to look at some of the most important
geometry numbers on an E mountain bike.
(upbeat music)
Reach, is measured from the center of the bottom bracket
to the center of the top of the head tube,
it's a great indicator of size
relative to and between brands.
And because fit can be changed,
the fact that it isn't a perfect indicator,
in the seated position,
it's incredibly important for your comfort whilst standing.
Let's have a look at the differences in reach then,
between brands and for one size,
now the size XL in a Haibike Fullseven is 454 milometers,
a Specialized Levo in size XL is 480,
and a Spectral On from Canyon in same size is 485,
so as you can see, there's quite a difference
between brands,
so it's actually quite difficult to make a generalization
when it comes to reach.
(upbeat music)
Now the head angle has a huge effect
on the handling of you E mountain bike.
Steeper head angles mean a more lively ride,
whereas slacker, is in general more stable
but you really cannot view this figure in isolation.
Now the numbers on head angles
are usually around 66 degrees for a mid travel bike
and about 63 for a downhill bike,
whereas a short travel beast will be about 68.
(upbeat music)
Brands measure seat angle differently
but slacker means more weight rearward
and steeper means more weight forwards.
The numbers are usually around 75 degrees
for a mid travel bike,
probably more important is your cockpit setup,
suspension design and how long is your chainstay.
(upbeat music)
The chainstay is measured from
the center of the bottom bracket
to the center of the rear axle.
Now the chainstay length is arguably
one of the biggest differences between E bikes
and non E bikes.
Now in terms of handling, a short chainstay means
more weight over the rear wheel,
which leads to sharper handling and an agile ride.
However, sometimes shorter chainstays
can sometimes make a bike feel smaller
and also taken to the extreme makes them tricky to tackle
on super steep terrain,
simply because your weight is forced too far back.
(upbeat music)
Wheelbase is measured from the rear axle to the front axle
of your E mountain bike.
But we're talking here about the close relationship
between the rear center which is the chainstay
and the front center of the bike,
which is measured from the bottom bracket to the front axle.
Now balance is key here, long and slack
or short and squirmy is the question,
well too long and slack
effects the agility of a bike,
it becomes a little bit boring.
E bikes need to be agile with a strong suspension design
that gives feedback, they need to be good climbers
and stable descenders.
Now I can't emphasize just how important
the relationship is between
the front and rear center of your E mountain bike,
because it really does effect the control
and also the weight distribution.
Now lets have a look at a comparison
between 250 mil travel bikes, a Levo and a Spectral,
both in size large.
Now, a Levo has a 781 mil front center
and a 455 mil chainstay.
Excuse the big thick stick.
The Spectral on the other hand, is a 778 mil front center
and 430 mil chainstay.
Chuck that stick away for a minute.
Now, if you compare that to a longer travel bike, say,
the Specialized Kenevo at 180 mil travel.
Now that has a longer 839 mil front center
and a 454 mil chainstay.
And the reason for that is
because it's a longer travel bike
and it needs that stability
and because it's been ridden in a down situation,
it needs that short chainstay
to dive in and out of the corners.
Now one final measurement on an E mountain bike
is the bottom bracket type,
measured from the center of the bottom bracket
to the ground,
and in general they're about 340 to 350 milometers,
which is the sweet spot.
Now look, I could probably talk geometry all day long,
but just because I can, doesn't really mean that I should.
Time then I think to either hit that ice cold pool
or head up into those beautiful Spanish mountains,
I think I'll go for the latter.
Ah (bleep) it.
(splashing)
(cheering and laughing)
Don't forget to follow us on social media
and give us a thumbs up if you like the video.