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What fork? What tire size?

I think you should knock a degree or two off both angles, but it can really be better determined by your dimensions. CS length should be at least 2cm longer. You want stability and the weight to be more on the bike than hanging off the back.
 

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patpend2000 said:
this would be for 700c wheels. I'm looking for fork recommendations, i was thinking something with 45mm rake, maybe the surly pacer fork.
Your not giving us enough info....What size are you? how are you going to carry your loads? why not build a fork? How are you going to construct it....

Initially I am wondering why the steep seat angle and slack head angle but maybe I am missing something.

Dave B
Bohemian
 

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pvd said:
It is poor form to just copy a frame. Why not just use that one? You should be designing around fit and handling. This will drive the shape of the frame. It really makes a difference.
Agreed with PVD 100%. No disrespect intended, but I fail to see why people want to entertain the thought of just copying a very nice existing frame/bicycle.

If you are just going to copy it, you might as well support Co-motion and buy it. You will save money, time and effort in the long run. It will be better than what you can make.

This is a journey, not just a item. If you can't build a fork then tackle that problem and wait until you can. Study geometry and know why you are doing something, not just imitating with no concept as to why. You still did not include any information about your personal dimensions, what your other existing bicycles are like or what you don't like about the fit etc.

I am not trying to kill your buzz, Just need more info to help you.

Dave B
Bohemian Bicycles
 

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pvd said:
Wow! It's super poor form to go and delete your thread on people.
I see this a bigger endemic issue. One of my biggest pet peeves.

Asking a well thought out question with enough info to actually reply seems to be something that many people cannot accomplish today. The other big peeve is when people do not receive the answer they were hoping for they just close up, fight back or in this case, delete the original post.

It is easy for many of us to pounce on those that do not know as much and are learning. That does not excuse poor question writing or behaving like an infant. The original question was basically "what frame geometry would work for me best, I want to do long tours" Ummm... let me consult the magic 8 ball and get back to you.

 

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I see a similar problem, although your explaination applies more to this particular case. I call it "the stupid question". Many people have been wrongly told throughout their live that there is 'no such thing as a stupid question'. Of course there is! I work teaching people and I always have to inform the students that a stupid question is one that, if you had asked yourself the question first, you could have answered it easyly. While in this case the OP couldn't have answered his question, if he had asked himself the question first, he would have seen that more info was surely needed and the answer is, at the least, complex.

It really comes down to basic consideration. Don't waste someone elses time without first investing your own. Try to solve your own problem and without success, seek the help of others.

Discussions and debates, however, are just plain fun.
 

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Discussion Starter · #13 ·
I deleted my question since it seemed that I had placed it in the wrong forum. I had posted my question here since it was the frame building forum and was asking about geometry for my first build. I had posted the geometry that I was thinking about using and was asking for feedback on the design.

When I posted that the geometry I was considering was similar to a current manufacturer's frame, I was told to go buy that frame.

How many frames have been built by individuals that have "copied" geometry, shouldn't they have just bought a frame from a vendor that already had that geometry? At least that's what I was told to do.

I have been professionally fitted before and I am currently riding on two custom made frames. I wanted to build my own frame since I need a 54.5cm TT and a 56cm ST, therefore I do not fit well on off-the-shelf frames.

Here's the question that I had posted before

"I'm getting ready to build my first frame, I want to build a frame for riding long distances such as centuries. I have selected this geometry

72 HT
74ST
44cm seat stays
I was looking for help with the fork selection but I was thinking about 45mm of trail.

I had forgot to include in my original post that this would be a road bike frame, constructed of steel tubing, tig welded.

I will go do some more research before I post another question here so that next time I can compose a more intelligent question.

Thank you for the responses and your time
 

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Sounds good. When you have a more thorough question, come back and ask. You are just at the beginning. Drafting your frame will answer some of the questions you have already.

1. Yes, you should probably just buy a frame IMHO. If you had worded your question with an emphasis on that you love working with your hands, that you would love the experience and journey, then maybe you should make your own. Building bare bones TIG frame for odd geometry (and it is not that odd) when others are readily available just doesn't make sense to me.

2. Everything interacts with other measurements on a bicycle. You don't want to carry any loads, then you don't need some of the constraints you are building into it. 44cm stays are not necessary if you are not carrying panniers. You feet are probably average to small and heal clearance is not an issue. What is your saddle setback? You make no mention of it so we don't know if a 74 seat angle is correct for you. They probably did that at comotion to increase the front center but there are other work-arounds. A 72 degree head angle was probably done for the same reason and 45mm rake will give you a lot of trail. Best to go to 50 or low 50's for the rake and bring your trial measurements down into the high 50's but then again you can't build a fork and finding a production fork with that much rake is going to be hard. Many 700c smaller frames are built with this exact geometry and most of it is to try and prevent toe overlap. If that is a serious consideration, even after playing with the numbers, you might think 650c or 26''.

3. what is it you don't like in your current "custom frames" how do they not service you for this endevour. What are some of the dimensions from those frames like reach, setback, handlbar offset etc. Because usually you don't want to go changing things up all that much if those are pretty close to the mark already.

Dave Bohm
Bohemian Bicycles
 
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