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Discussion Starter #41
I want to thank you guys again for all your help, Im currently buried in absorbing all the material you guys have me. Im reading the textbook,(discovered I really like Tony Foale, kind of a smart guy) learning the vocabulary to better articulate my future questions. Like everyone has stressed, I gotta learn the basics. While I get a grip on the suspension and learn my way around the mechanics of it, Im going to go back and look at what I really want out of this bike. Also there is plenty of electrical work to do so ill probably work on mapping it out.

@Witworth Oh wise Witworth I believe a man makes his own fate, and if mine is to die by my own invention then so be it. Also...
1: I only have money for one shock so I cant buy two :p
2:What the hell would a yogurt maker do for a motorcycle?
Why do you hate my idea so much man? Why won't you just help me do it right, i'm not in a rush too do it wrong, in fact I'm not in a rush to do it at all. This is a project of mine, an experiment if you will.
Even if it fails, so what? I want to learn real engineering not just classroom bullshit, if at the end of it all I have a working bike great, if not well by then im sure i'll have learned a thing or two.

@TCed your right I will get there maybe with a few busted tools lol but ill get there. That was the very first time I touched any of those tools, no instructor or direction. I thought it went great lol I was ecstatic I hadn't burned my self haha! But in all seriousness I fully understand that I don't have the skills, knowledge or experience for what I want to do. But if I try I know I'l learn little by little and eventually I get it. After all thats the reason I came here I saw the expertise some of the guys around here have, and I need their help, so I can learn.

@Mark Burton no way dude I haven't welded anything except scrap piping to practice on. Haha learning to weld properly is definitely on my to do list.

I understand some of you guys take all of this super seriously because some of you might have worked professionally in motor sports or, have been doing this stuff for years, or are even work currently as mechanics, I also know all of you started from somewhere.
This is where I'm starting from.

PS: I didn't know who RSD was, now I do thanks again!
 

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Very good reply Delson. Keep trying, and you will succeed. Non of us were born able to weld, grind, drill holes, and paint, it takes lots of time and practice. So what if you stuff up, it's your money and time you've wasted. It's the only way to learn sometimes. Fortunately you have the vast knowledge of this forums members to help you. Listen to them it's to your advantage.
 

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" I believe a man makes his own fate, and if mine is to die by my own invention then so be it. " I agree entirely. Just don't post your attempts at "engineering" and therefore encourage other guys to die who might read your blog and copy your efforts. It's called being responsible.

You pretend that you want to learn, but in fact you just want people to assist you in tinkering with something that you have zero understanding of. And crucially, you are not listening.

You really have to ask yourself: " Why do I want to fit a single shock in the first place? " . If the answer is "because I want to" , go get a tattoo or a yogurt maker. If any regular poster on this site thinks this project is even worth undertaking, I would be very surprized.

I can't speak for other guys, but I learnt my engineering skills from professionals, in my own employment history and receiving recognised qualifications from professional instructors. I didn't start out on complicated engineering projects that could kill me.

Go do a certified welder course.

Danger, is my business.
 

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Discussion Starter #44
Witworth it is the expertise that you possess that I look to learn from, I look up to professionals like you, your instructors, because I aspires to be one, one day. Sounds all corny but its true. I am listening, Im just choosing to listen those who are looking to help me. I could be brash and just say "because I want to" and tell you up yours! But I would never because I respect you, your craft and your experience.

Why do I want to fit a single shock in the first place?
I want to do a monoshock suspension on this bike, because....
the bike needs a suspension.
I have always admired the look of a monoshock.
I know its possible.
I know it will be challenging.
It will force me to learn new concepts.
I have not seen it done on this bike.

I could google reasons for mono versus dual and put here because I don't have the technical knowledge to tell you from a technical aspect why I want to do it.
After all the question stands "why do i want" not "why does the bike need" there is no need for any of this. This is all of my own will, simply because I want this project, I want to see it through, I want to accomplish this.

If this is your forum and you ask me to leave I will, but Im just going to go find a way to make my idea work. Maybe along the way I will learn the proper technical reason for actually fitting a monoshock to this bike.

*DISCLAIMER*
Under no circumstances do I condone, or promote this project, its designs, or ideas as safe.
The designs and ideas posted by me on this thread and my blog are experimental and have not been tested or approved by any professionals.
If you decide to recreate or pursue any of the ideas posted by me in this thread or my blog, do so at your own risk!
 

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"At approximately 8pm Sunday evening, I primed the spark plugs, and carburetors with starter fluid. I then turned the key in the ignition, and put the bike on full choke. With the starter button pressed the bike caught on the first try, my bike is now fully operational."

Starlord,
Drop the blog and spend that time in a manual for your bike.
ed
 

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Discussion Starter #48
"At approximately 8pm Sunday evening, I primed the spark plugs, and carburetors with starter fluid. I then turned the key in the ignition, and put the bike on full choke. With the starter button pressed the bike caught on the first try, my bike is now fully operational."

Starlord,
Drop the blog and spend that time in a manual for your bike.
ed
haha, I have to say between that day and today I know a lot more. Not even a day after that did I find out that the bike was not fully operational. lol What I did mean was that the engine was fully operational, as in running.

I did buy the manual and I have read very thoroughly about every section that I have worked on, on the actual bike.
I will probably make a post about everything I have actually done on the bike so far. Just to bring anyone looking at my blog up to speed, also that way people can suggest what to do next or help me catch things I have missed.

But yeah reading that It does sound retarted. Lol but you know what can I say I was excited and I had just seen/heard my first motorcycle start because of the work I learned to do and did myself.
 

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It's all good.

Keep the bike operational and in one piece. Striping it done to nothing without a precise plan, is a prelude to writing a CL advert to get rid of a box of bits.

Danger, is my business.
 

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Take a look at the monoshock setup for the 81-82 Yamaha Virago 750/920. It is a very straightforward arrangement. It is not the best, but will work fine for any kind of use a VT750 would get.
 

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Take a look at the monoshock setup for the 81-82 Yamaha Virago 750/920. It is a very straightforward arrangement. It is not the best, but will work fine for any kind of use a VT750 would get.
The Virago swingarm geometry and shock is not really compatible with the VT750C frame. For a start the shock is very long by modern standards and the front shock mount on the Virago is virtually ten inches inside the hollow Virago main frame tube. It's a total re-engineering of a VT frame to enable the use of a pretty crappy quality Kayaba shocker to begin with.

Virago swingarm and shock images CFG79ZDI.jpg

Danger, is my business.
 

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Discussion Starter #52
Take a look at the monoshock setup for the 81-82 Yamaha Virago 750/920. It is a very straightforward arrangement. It is not the best, but will work fine for any kind of use a VT750 would get.
Thanks Kenessex:
I'll take a look into it, if I want this suspension to work I am going to have to make some sort of cross sectional mount on the top section of the frame to mount the top end of the shock. I'll have to check how high up the that triangle (from the yamaha swingarm) reaches. Also I'll have to see if the driveshaft will co-operate with my bike.

This my plan so far, Witworth I'm counting on your support for this one....
frame explination.jpg
So by cutting off that section of the triangle and making that new section in green, the mounting point for the top of the shock can be higher (maybe ideal for the longer shock) if i were to go with this swing arm. Either way I want to raise the seat on the bike so I figured this would be helping all causes.
 

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The rear triangle of the frame does not just support the seat on a monoshock bike. It forms a vital triangulated "box" that braces and reinforces all on the main frame and the swingarm pivot area.

If you Chop Chop the frame where you have indicated, you will effectively have reduced the rigidity and structural integrity of the frame by at least a third.

A "toy" café rear subframe for the seat will provide virtually no bracing for the main frame.

Right now you don't know, what you don't know about suspension modifications, and are still dreaming and not asking any questions about how and why you approach this effort.

Danger, is my business.
 

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Discussion Starter #54
The rear triangle of the frame does not just support the seat on a monoshock bike. It forms a vital triangulated "box" that braces and reinforces all on the main frame and the swingarm pivot area.

If you Chop Chop the frame where you have indicated, you will effectively have reduced the rigidity and structural integrity of the frame by at least a third.

A "toy" café rear subframe for the seat will provide virtually no bracing for the main frame.

Right now you don't know, what you don't know about suspension modifications, and are still dreaming and not asking any questions about how and why you approach this effort.

Danger, is my business.
I do see your point. About the losing structural integrity, and because of that I have also considered approach below.

frame splanation.jpg

However, If I went with this method I might not have the room needed for the brace along the swingarm.(blue circle)
If Im going to make this happen, something is going to be coming off (red) in order for anything proper to be put on. I can't just throw thing in there.

I need to design something stable that will give me the desired height and the room for the suspension.
 

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For a start you have to find out the exact length of the stock shocks and make some accurate struts to be able to measure your correct ride height.

I can't see any need to remove the RED tube for shock / brace clearance.

Forget jacking up the ride height for "stance looks", because it will wear out the shaft knuckle and do all sorts of bad things to the handling. I doubt a Virago swingarm would fit, in any case.

Your gas tank need to be much further back for handlebar clearance. Forget clip-ons with the raked-out, big-trail frontend.

You need to work out your suspension mods, well before making a seat subframe. One comes before the other.

BTW, many of the so-called "café racers" customs with high seat subframes are comfort and functional nightmares.

Danger, is my business.
 

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Discussion Starter #56
Ahhh Witworth, you're growin on me. I just realized my wording sorry, the red part doesn't need to come off for the swing arm, my post was not very clear there. With that design I didn't feel like it(the red part) would be necessary there. the part that would mess with the swing arm would be this "/" <--- part of the triangle, because of the clearance between the wheel and the frame. Thats what I meant by "I might not have the room needed for the brace along the swingarm.(blue circle)".

About ride height I have three options the way I see it.
1. Raise the seat at least a bit otherwise the tank is going to be at my chest.
2. Lower the tank, or get a new one. Cause right now its sitting at about my chest.
3.yogurt maker.

(I know for sure the swingarm comes before the sub frame that like thats bikes 101 pffft) :p
Yeah I know it has to move back. Was think about bending/denting the underside of the tank to make it fit around the frame, and the head of it a bit so I have some room to turn. But I'm afraid of it buckling and just crumbling. I might try it any way I got the tank dirt cheap. If it doesn't work then I'll just have to get a new one.

I bit side tracked there, back to the task at hand!
I like the idea of the struts to mock the original height it makes sense.
Im gonna do that, I just recently got a lift for the bike, I have been meaning to get it up so I could work around it. That will definitely help for working on the suspension.


*face palm*..... I just bought clips-ons like wednesday, they'll be here tomorrow!
 

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I think those rigid struts bolted onto the twin shock mounts were just used to lower the rear end of the bike. Might be worth finding out the length of a standard shock and mock it up by drilling flat plate and bolting them up.

Your seat height will be improved straight away by putting standard shocks back on.

Just a thought
 

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I think those rigid struts bolted onto the twin shock mounts were just used to lower the rear end of the bike. Might be worth finding out the length of a standard shock and mock it up by drilling flat plate and bolting them up.

Your seat height will be improved straight away by putting standard shocks back on.

Just a thought
I think you're spot-on with this. Have a look at the angle of the swingarm / drive shaft compared to the angle of the motor - it should be level at least, not drooping down like it is.
 

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For a start you have to find out the exact length of the stock shocks and make some accurate struts to be able to measure your correct ride height.
Just noticed Witworth also made the same suggestion!
 

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You need to get a far shorter and smaller tank to suit this build. The big tank does not suit the frame or the motor.

Danger, is my business.
 
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