design frame for motorcycle and related loads that must endure

[A.V.9]

hello to all I am new to the forum
then I am trying to dimensional a frame of a bike or better than a pit bike (i.e. a motard a smaller fur) .
I started with goaries to look for measurements from regulation ocom interasse height and diameter tires.
secondly or given a first sizing but that concerned only design and trying to apply the technical solutions I had in mind.
At this point I have a 3d project made on autocad which is the only cad that I find to use discreetly I just started a v5 cat course that is the program I would like to use from here onwards.
after the frame design I wanted to know if the geometries I used can go well depending on the loads de must endure the frame to the ra I documented and I found something but I would be grateful If there was someone who has the clearest ideas of me and could give me a hand telling me what are the loads that press a trell of a bike and explaining how to calculate them, I can see if what I found and right.other thing I would like by catia v5 to see if my frame resists you have loads to which it is sunken , there is the possibility (after making the 3d model on catia) to apply the loads and see if the structure occurs? You can tell me where I find a manual download that explains to me ? I'd love to calculate it by hand, but how do I do it? I can solve flat rectangular structures what very close a frame but the frame and 3d how do I?? If you can help me, I'd be grateful

 

[gerod]

Hello and welcome.
1. If you're new, you'll show up!
2. read the rules
3. Wait for someone to answer without resuming the discussion (go to read the rules well and you will see that bringing the discussion to the foreground is not consistent!)
4. is not the suitable section and therefore the move in the design section
5. downloading a manual makes me think you're not using a license... let's say regular. Maybe I'm wrong?
6. what you're asking is quite complex to do and if you don't have a minimum of fem calculation experience I think you could bleach the sizing.
I do not know the motorcycle scope but the loads apply by studying the situations that give the maximum stress. here however there are the vibrations to consider and therefore not only a mere static calculation.
I think it's not a thing that works out in a forum.
a greeting

 

[sail]

a way to inspire to have an order of magnitude could be assessing the removals. knowing at least the size of the shock absorbers and springs could already begin to understand the order of magnitude mentioned. Of course everything will have to be coefficent to the need to sleep quietly. Otherwise you could start by evaluating the pins of the wheels of competition.

I assume you're talking about a school project or something that will remain on paper, right?

I agree with gerod when he says it's not a trivial argument. especially for the part of fem. is not something you learn in a few days.

Good study.

 

[A.V.9]

Hello and welcome.
1. If you're new, you'll show up!
2. read the rules
3. Wait for someone to answer without resuming the discussion (go to read the rules well and you will see that bringing the discussion to the foreground is not consistent!)
4. is not the suitable section and therefore the move in the design section
5. downloading a manual makes me think you're not using a license... let's say regular. Maybe I'm wrong?6. what you're asking is quite complex to do and if you don't have a minimum of fem calculation experience I think you could bleach the sizing.
I do not know the motorcycle scope but the loads apply by studying the situations that give the maximum stress. here however there are the vibrations to consider and therefore not only a mere static calculation.
I think it's not a thing that works out in a forum.
a greeting

You're wrong because I didn't say I downloaded a manual but to make me a little culture about the stresses I bought a book called dynamics and technique of motorcycle so I don't know what you mean.


However, what I would like to do is not to stop at the card but to put this pit on track and see if everything works:

 

[peloritano]

now I am in a hurry but since the bikes are my passion and I take care of changes I am very interested to carry out this discussion

 

[A.V.9]

if to someone can interest I can tell the loads that otrovated and how to calculate them

 

[peloritano]

Of course I do.

 

[A.V.9]

then I found the following braking force loads that is doing the pilot and motorcycle mass * the decelletion this force goes to act on the front wheel in the opposite direction of march

 

[SER.CAD]

in the design of maximum of a motorcycling frame, many years ago, the 70's early 80's considered (besides the mass of the chassis, the motor, the accessories the pilot (100kg), the fuel etc...) also the maximum torque of the bike applied to the baricentre on the frame frame frame frame frame frame frame set on the steering rod, to have a good predimension of fatigue in modern practice to do a pre-dimensioning "of the handmaid" you can still act so ... to push towards "racing" configurations ... the loads you have to acquire them ... using a "similar" motion (weight, calibration step supports) etc... building load cells with strain gauges carrying on the shoulder a very expensive acquirer... the thing not simple trivial ... I would like to tell you ... do first ... how do many motorcycle houses

 

[sampom]

now I am in a hurry but since the bikes are my passion and I take care of changes I am very interested to carry out this discussion

in the design of maximum of a motorcycling frame, many years ago, the 70's early 80's considered (besides the mass of the chassis, the motor, the accessories the pilot (100kg), the fuel etc...) also the maximum torque of the bike applied to the baricentre on the frame frame frame frame frame frame frame set on the steering rod, to have a good predimension of fatigue in modern practice to do a pre-dimensioning "of the handmaid" you can still act so ... to push towards "racing" configurations ... the loads you have to acquire them ... using a "similar" motion (weight, calibration step supports) etc... building load cells with strain gauges carrying on the shoulder a very expensive acquirer... the thing not simple trivial ... I would like to tell you ... do first ... how do many motorcycle houses

:finger:
quoting both

greetings
Marco:smile:

 

[peloritano]

So if we talk about the loads that act on the frame, I'd put some extra ones on it..... as far as copying is certainly a way.... But if you use your head and you study a little bit, I think you get to something good.............

we consider designing the naked frame of a motorcycle......... .
I would consider the points in which forces act knowing a priori that the whole structure has its own weight... .
So starting from the front, where the forces are applied is the steering wheel.
here in addition to the deceleration force to which the bike could be subject I would add the force due to a possible shock (I imagine taking a sidewalk), also I would add a torque moment (when you make a curve in red valentine style you practically send a torsion on the pipe...... going to the central part I would consider as someone has said the weight of the fuel, the driver and passenger forces (you could always approximate
then you pass to the weight of the motor divided on the attacks of the same to the frame.... in these points I would also add the strap shot that is created due to the presence of the chain, then there are the rider's pawns on which I would apply half of the weight of the rider and idem for the points of attack of the passenger's pedane, then I would consider the concentrated force that exercises the rear shock on the chassis and finally the maybe that act on the pin of the fork.... here always apply the pull of the chain of course also for the attack point of the rear shock absorber I would consider the force due to shock..... .
all other onboard components (battery, control unit etc. etc. etc. etc. I would consider them as concentrated forces applied where you think to put the fixing brackets)
last I would run a real hard on the part around the engine...... here to make simplified calculations I would consider an oscillating mass where the mass could be that of the motor shaft and the pistons (you find them in many magazines). .
if someone has something to add well come

 

[peloritano]

I forgot... a frame is in balance because all the forces acting above it are in balance..... to proceed to the design (e.g. through fem) you have to consider constraints to make the isostatic structure..........usually you consider an ink at the point of attack of the fork.......

 

[SER.CAD]

I have worked five years in the motorcycles, nothing of this is done.

 

[peloritano]

How did you work? ? ?

 

[sampom]

..e questi:http://www.pcm.unifi.it/aias/xxx_convegno/pdfs/al119.pdfhttp://torvergata-karting.it/article/articleview/15/1/6/http://www.aiasonline.org/aias2005/articoli/art200.pdfthe matter is vast and complex..:biggrin:

greetings
Marco:smile:

 

[A.V.9]

So if we talk about the loads that act on the frame, I'd put some extra ones on it..... as far as copying is certainly a way.... But if you use your head and you study a little bit, I think you get to something good.............

we consider designing the naked frame of a motorcycle......... .
I would consider the points in which forces act knowing a priori that the whole structure has its own weight... .
So starting from the front, where the forces are applied is the steering wheel.
here in addition to the deceleration force to which the bike could be subject I would add the force due to a possible shock (I imagine taking a sidewalk), also I would add a torque moment (when you make a curve in red valentine style you practically send a torsion on the pipe...... going to the central part I would consider as someone has said the weight of the fuel, the driver and passenger forces (you could always approximate
then you pass to the weight of the motor divided on the attacks of the same to the frame.... in these points I would also add the strap shot that is created due to the presence of the chain, then there are the rider's pawns on which I would apply half of the weight of the rider and idem for the points of attack of the passenger's pedane, then I would consider the concentrated force that exercises the rear shock on the chassis and finally the maybe that act on the pin of the fork.... here always apply the pull of the chain of course also for the attack point of the rear shock absorber I would consider the force due to shock..... .
all other onboard components (battery, control unit etc. etc. etc. etc. I would consider them as concentrated forces applied where you think to put the fixing brackets)
last I would run a real hard on the part around the engine...... here to make simplified calculations I would consider an oscillating mass where the mass could be that of the motor shaft and the pistons (you find them in many magazines). .
if someone has something to add well come

Of course what I wrote was just a load
then we proceed with order
I am now calculating the various loads I am aware of which I am:
braking force
vertical forces on the front and back
torque moment(which I am still trying to understand better and I have no formulas that allow me to calculate it and understand where it is applied (if anyone could give me a tip)chain shooting on the fork

what I did not understand how to do is how I can size the frame tubes based on these loads and the frame design I designed as I do??

 

[sampom]

......
torque moment(that I am still trying to understand better...... where it is applied (if anyone could give me a tip)

while flying..:biggrin:
between steering rod and fork pin

greetings
Marco:smile:

 

[A.V.9]

Thank you very much

 

[peloritano]

As for the value to be applied at this torque moment I would put myself in the worst conditions, i.e. I would consider to incite the weight of the full wheel + pilot and passenger and I would apply this value as a transversal force in the contact point of the front wheel to the ground.. This force multiplied by the distance between the steering column and the contact point of the wheel to the ground gives us the torque moment to be applied......... take into account that the torque stiffness is a very important factor for a motorcycle. track motorcycles must have a very high torsion stiffness while cross bikes can afford a lower torsion stiffness. . .
Now if you want to design healthy plant structure you should use fem software...... If you want to make the calculations by hand is long but you can do the same.... with the fem software you have to assign the sections (see some motorcycles around) and then check the results with subsequent optimization completely

 

[Exatem]

I am not an expert on matter but I am passionate about motion and try to say mine.
every time a new motorcycle comes out, you hear about “increased rigidity of the frame” but in reality the frame should not be “absolutely” rigid (there are motorcycles, like the duchies from gp that have slightly reduced the rigidity of the frame compared to previous frames). It is a value that must be interfaced with others such as suspensions, the motor (which often has functions itself of part of frame ...).
the overall rigidity will make the bike more or less accurate and is a value that the designer must establish knowing that he will not have a frame absolutely “rigid” and inguidable. Therefore it must analyze longitudinal and torsion rigidity considering that suspensions can and should be helped by a certain elasticity of the frame. for many years in motocross we avoided aluminum frames because too little elastic than those in steel, then the advances in the suspensions have made these obstacles overcome by realizing motion from very competitive crosses (honda). in the road the things change a little, if the frame is too yielding, it risks triggering oscillations that go to interfere or vanify the work of the suspensions. the torque flexibility instead triggers disassembly of the bike hardly manageable. the stresses of this genus are located in the steering rod and in the attack of the fork. in any case the frame, backbone of the bike, must respect two parameters: maximum resistance and minimum weight.