[Tetreault]

it's looking good, i would be very interested to try it. almost a street trials frame that would be a blast to ride.

have you figured out your means of production yet? what tubing are you going to use?

 

[Dirtjumper999]

I'd only be making one or two for me, not looking at starting a company or anything off of it. I'd like to use Sanko Chromoly, but it's a bit expensive. I will probably make a proto out of random 4130 tubing that I can scrap together, just to see how everything would go together.

 

[versusblitz03]

Could you explain to me what the top view is of? Im a mechanical engineer and im curious as to this design.

 

[Stoked]

Could you explain to me what the top view is of? Im a mechanical engineer and im curious as to this design.

i'm no mech engineer bit its a cross section of the tire in the rear end. give me your degree now

 

[Dirtjumper999]

Could you explain to me what the top view is of? Im a mechanical engineer and im curious as to this design.

Yep lol it's the view of the chainstays, basically giving you an idea of what the tire clearance would be. It also shows you weather the chainstays have an s-bend, straight, etc.

 

[Dirtjumper999]

I have been playing around with SketchUp a lot lately, so I decided to make some renders of the frame as well as some sprocket designs and a weird stem design. Names on top of each.
Air Frame

Bloq Stem

Sprockets

Feedback is welcome. Criticism encouraged.

 

[ServeEm]

Curious if you'd be clipping your toes on bar spins. The stem looks like a cool idea but wonder if it could take the load.

 

[Dirtjumper999]

Curious if you'd be clipping your toes on bar spins. The stem looks like a cool idea but wonder if it could take the load.

Nope, did the measurements and with a 465mm fork and a 26" wheel with a 2.4 tire turned 180degrees, the wheel would have 2.5" of clearance from the pedal (w/175mm crank).

As for the stem, its the idea at its most basic form, there will definitely be some modifications because as it is I don't think it would take the load.

 

[nwd_26]

1) If you ever made a frame you'd know that 14.25 is waaaay not possible... for a 26. Even if you used a yoke (non tubes) at the BB you'd still only get to about 15.25..

Well you're only off by about an inch....

14", 26" wheel.

 

[Dirtjumper999]

Well you're only off by about an inch....

14", 26" wheel.

Agreed, as most people riding steel dj frames from boutique companies have about ~14.5" chainstays with room to spare.

 

[Tetreault]

Bloq Stem

Feedback is welcome. Criticism encouraged.

the frame looks great but for holy ****ing **** ass tits is that a tongue and grove on the bottom of the stem faceplate?

 

[Dirtjumper999]

the frame looks great but for holy ****ing **** ass tits is that a tongue and grove on the bottom of the stem faceplate?

Yes lol, the stem idea is still at it's most basic form, I still have a lot of changes to make on it. The tongue and grove idea is something I just had to see out of my mind.

 

[Stoked]

bottom row in the middle looks similar to the old kevin porter profile sprocket.

here's an idea from Ken at Zodiac eng. ha. would sell like hotcakes.

 

[Dirtjumper999]

bottom row in the middle looks similar to the old kevin porter profile sprocket.

here's an idea from Ken at Zodiac eng. ha. would sell like hotcakes.

Yea, I see the similarities there. Might make some tweaks to make it less so. As to the second one

 

[Randomshot]

hahaha +1^

 

[mattt]

Agreed, as most people riding steel dj frames from boutique companies have about ~14.5" chainstays with room to spare.[/I

yes i guess it is possible but... at the cost of compromising with smaller tires, weaker stays... less clearance for tire/cranks/chainring.

Referring to a frame with a 14 inch stay as a "dirt" frame is... wrong. What would be the advantage of having that short of stays on a dj frame? The consensus among BMX companies is that longer stays are more stable, hence 20" dirt frames are ~14.25". My thought is that the same is true for 26"... a 15.75" is more stable than a 15" at higher speed... which puts to shame a twitchy, loopy 14" frame anyday.

Designing stays is a balance of clearances. Intending to put the tire that close to the BB, you have to use a yoke or crimp chain stays. These are compromises. (I would always favor a yoke over crimping, as crimping significantly weakens a highly stressed area) But even a yoke is a compromise. Tonic fab actually made a much wider BB and still only stuck to 14.56".

The shorter ones:
Tonic fab's Howie stays: 14.56"

Atom Lab" 14.5"
(These frames have chain stay yokes)

Blk Mrkt is 15.5"

NS Majesty is 15"

Superco 15"

Most common dj frames are actually around 15.6"... i dont know what other "boutique" frames your referring to.

Why make a frame designed exclusively for street around a wheel size that has the most benefit on dirt?... Are not 24" wheels a much better choice for street/dj frames? ppppppppppth!

_matt

 

[sealclubber]

actually 24" wheels are best designed for all that falls in this subforum

 

[mattt]

actually 24" wheels are best designed for all that falls in this subforum

what

 

[Dirtjumper999]

Shorter chainstays will mean stronger chainstays actually. In addition to that, the tire clearance will be about the same as most other dj frames. The bottom bracket will be 73mm wide instead of the common 68mm, I am doing this because that will allow me the extra clearance for the tight stays, and I am not worried about being able to fit a +30t chainring on it. As for their length, shorter chainstays are simply flickier, plain and simple. If you're frame has the option of sub 15" chainstays, ride the bike with the wheel at the extents of the dropouts, and then slam the wheel, and tell me how it feels.

24" wheels are not out of the question actually, and will be an option regardless in this frame, (the chainstays will have no s-curve to hinder tire clearance with a smaller wheel). As for me though, I ride street best on a 26, I ride park best on a 26, and I ride dirt best on a 26. Not to mention that if I want to hit something a bit bigger e.g. drops, I don't have to be worried about the bumpy ride.

As far as shorter stays feeling loopy, quite the contrary, hoping on a bike with longer stays feels super sluggish and non responsive. I personally feel much more stable with a shorter chainstay among other things. That being said think a big part of a bikes stability comes from the headangle.

 

[TheTruth]

If you build this. I want you to send me a test frame.

 

[ServeEm]

I think the debate on the stay lengths feeling one way or another useless. OP prefers shorter for all around play makes sense, plus it's personal preference since it's being built for him solely.

 

[ServeEm]

Bloq Stem

Hey I was thinking while sitting on the toilet this morning, why don't you flip the design with the tongue/groove on top. Cuz the load would occur more on the bottom right? Might still need to beef up the material or tweak it a bit but the concept should work. Like what I did with it below.

 

[w00dy]

I did that once at my old job. 1/2 million dollar waterjet machine makin little dongs...

 

[ServeEm]

I did that once at my old job. 1/2 million dollar waterjet machine makin little dongs...

LOL Are you serious. That's hella funny

 

[Stoked]

I did that once at my old job. 1/2 million dollar waterjet machine makin little dongs...

Dick sprockets for everyone!

 

[Dirtjumper999]

So the past couple weeks have been a design frenzy, and after a lot of push from my family and friends, I am entertaining the idea of creating a company. With that, I would like to ask everyone who creeps this dead dj forum, a few questions.

1. Yay or Nay on the possible logo :

2. Tell me what you dislike about the frame you are riding (DJ, slopestyle, street, etc)

3. Would a tapered headtube on a dj hardtail be an attraction or a deterrent for you?


Thats all for start, and I'll leave you with a bit of eye candy. While the dirt/park/street parts and frames would be my starting products, I have been toying with suspension designs:

 

[Dirtjumper999]

Is this forum that dead? Or does everyone thing this sucks... I want terrible critique if thats what it takes...

 

[pnj]

I have no opinion on the hardtail. Deity makes the only frame I'd run if/when I buy another 26.

What's the deal with the green circles on that logo?

 

[Dirtjumper999]

What's the deal with the green circles on that logo?

Loose/artistic representations of leaves on a tree, but I have since decided against "Dig Life Cycles"

 

[demo 9]

Logo is good, fully looks bad, hardtail looks good as far as riding it would go, but i think the bent down TT is ugly (face it, alot of people buy on looks)