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Bicycle framebuilding. Details of suspension.

Bicycle framebuilding. Details of suspension.


Hi everyone!
The spring has come bringing the sunny
weather and joy. You’ve just seen it, right? Today I’d like to tell you
how to connect a rear triangle
with the front one, show you suspension layout,
pivot axles and joints. Show you how
it works all together. I can’t say we’ve come up
with something special or unusual. We’ve just chosen
the most reliable option in our opinion and used it in our frame. The main idea was low maintenance along with reliability
and longevity. Only a few people like to tinker with
their bikes and it’s not me. I prefer riding a bicycle rather than
tinker around with it. The majority of suspension parts were made here by us. I machined pivot axles, all spacers and so on. In future we plan to make
everything on a CNC machine, if there are 10-15 frames. For now we made everything
for 3 frames ourselves. Because prototyping is
the best way to understand a product.
Whether it has any production disadvantages, how to make it better and improve production process. That’s why we had to spend hours to make these parts and before I start I’d like to show you the process of making a detail. Specifically, these hexes for small pivot axle and
main pivot axle nut. To save some time I’ll show you only
a part of this process. Hope you liked it. Well, let’s start with
a front triangle. Bearings are fixed
in the main pivot tube of the front triangle. As you can see it’s quite big and it has 30 mm ID. And we have a pivot axle that also has 30 mm OD . Put it in here like this. Quite tight and
through both bearings. And as I’ve already said this is 30 mm ID where a rear triangle pivots. The next part I’d like
to talk about is this aluminum spacer that transmits thrust force
to the bearing. This spacer has
a silicon seal along the edges, so when you fix the pivot axle
and press it to the bearing the silicon seal covers all bearing flange area. It’s additional protection
from damp and dirt. At least it’ll be less dirty and its inner part will be
additionally protected. The bearing has an outer flange that bumps against the edge
of the main pivot tube. It means that you can’t press-fit
it crookedly or wrongly. It always centers according to the edge of the tube and only like this. Just press it until tight. We use “Enduro
Bearings”, all types. For example,
for a yoke link like this and for the main pivot tube. Let’s unpack it. I guess you can see it. The bearing has a flange that
helps to bump into something. Such size of the bearing provides required rigidity and longevity of
the whole unit. The bigger the bearing is,
the longer its life. Under the equal load. So, if you use
a smaller bearing, remember its
lifetime is shorter than the bigger one. As for rear triangle, the same pivot axle
should be put into the right and
left joint-hinge. It pivots here. We made it the same way
as Shimano hollowtech. That means there is
the right side where the pivot
axle is fixed tightly. I’ll show you how it’s fixed. And there is the left side
where you clamp it like a secure lock. Thru axle with 30 mm ID gets through
the frame and swingarm. Swingarm has a joint-hinge
like that for the main pivot axle. We made it on
a CNC machine. It has a fitment bore
with right tolerance and a retainer plate. Which means that
the pivot axle has a ramp that bumps into the plate
while putting the axle into the joint-hinge. It prevents axle from rotation and fix it tightly. Then you set the spacer that bumps into the bearing. And all this stuff gets through
the bearings of the front triangle. Clamp the axle with the left hinge. But before that clamp the main pivot
axle with a nut. This is a 12 mm hex. It’s a very simple system. As for rear axle, it’s a 12 mm thru axle . Syntace system. There is a specified
derailleur hanger, bolt-on and a threaded insert. Which means
it’s possible to buy spare parts
almost everywhere. There is no need to look for
them in specific shops because it’s
a well-known standard. Here we have
a 12 mm Syntace axle. It goes like this. I suppose everyone
knows how to do it. All details are replaceable: a threaded insert,
a derailleur hanger and a bolt that presses it
and tightens the insert. The next detail of
the rear triangle is a yoke link pivot axle. For convenience I’ll use another detail to show it. It is a yoke link with press-fitted bearings that have a 15 mm ID. We insert a small
15 mm axle. It has a hex but we won’t use it any further
cause it’s unnecessary. The axle gets through
the bearing, then we put a spacer that bumps into the bearing. Then goes… this detail is used in
the rear triangle. Just as an example. Insert an upper hinge and tighten by the bolt. Having such a yoke link allows you to choose
another system rather than single pivot
frames like “orange” type. Such type has
a sliding friction or bushing system. We use bearings, so it’s a rolling
friction system. It makes suspension more sensitive to
surface roughness and increase its longevity. Look how it works. That’s all for today!

8 thoughts on “Bicycle framebuilding. Details of suspension.

  1. что мешало зделать бурт внутри рами, на шарнире више каретки,также можна тупо пресовать до упора и прома можна без гемора заказать…

  2. все круто, но что со звуком, или это только у меня так, смотрел с субтитрами

  3. Есть примерная калькуляция, во сколько обойдётся рама для 27.5"?
    А так успехов! Самому стало интересно чем данный проект закончится и собрать себе вел на такой раме.

  4. Excellent series. Does the addition of the yoke provide other benefits like the ability to tweak the leverage rate? I like the simplicity of single pivot but not the falling rate leverage curves typically unavoidable in those designs.

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