# School me on Paragon Adjustable dropout



## mimi1885 (Aug 12, 2006)

Or any adjustable drop out. How durable is it. Is it for the singlespeed only? It's available as an option for my potential next 650b bike. I did the search but nothing came up. Thanks:thumbsup:


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## jcaino (May 26, 2007)

They're durable - they're probably one of the most popular adjustable dropouts. You can get a slider with a derailleur hanger.


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## G-reg (Jan 12, 2004)

They are plenty durable. Spring for the upgraded bolt kit, the hex on the std 6mm stainless bolts are the weak link. 

I'm a fan of Paragon's rocker drops, if your specs allow the disc caliper chainstay-ish mounted. IMO they are much more asthetically pleasing, less likely to slip, and build a stronger rear triangle.


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## febikes (Jan 28, 2011)

Standard bolts seem fine. I have been riding my for a long time and never had a problem with the standard bolts. They hold good and unless you are a monkey with a wrench I don't think you will strip them.

I like the hooded style ones.


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## mimi1885 (Aug 12, 2006)

Thanks for sharing. I figure it'd be great addition even for geared bike as I can make more room in the back when needed


Sent from my iPhone 4s using Tapatalk


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## Buter (Sep 15, 2012)

Good timing - I was just about to ask a similar question. 

Do you guys think that these adjustable drops would survive on a DJ bike?

Cheers

Buter


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## restlessrider (Nov 29, 2007)

Buter said:


> Do you guys think that these adjustable drops would survive on a DJ bike?


They are easily stout enough for a DJ bike - tubes will fail long before those d/os will fail (I have built several with the tab type). Well designed as is all Paragon stuff


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## J. Random Psycho (Apr 20, 2008)

Sadly, no Wright style rocker dropouts seem to be available.

But here's something new they are rumored to roll out soon:









I only have this picture link and no other info. Would be great to read up on it.


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## mimi1885 (Aug 12, 2006)

That looks awesome, thanks J.


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## J. Random Psycho (Apr 20, 2008)

But I'm not sure how it works. There seems to be a Titanium part outside, welded to frame, and a black Aluminum part, connected to the Ti with a pivot (?) at the top. But what is that pickaxe-looking adjustable part, how does it work? And what's behind that oval hole in Ti part between hub locknut/adapter and Ti.


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## unterhausen (Sep 28, 2008)

looks like the Black Cat dropouts, only backwards


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## mimi1885 (Aug 12, 2006)

J. Random Psycho said:


> But I'm not sure how it works. There seems to be a Titanium part outside, welded to frame, and a black Aluminum part, connected to the Ti with a pivot (?) at the top. But what is that pickaxe-looking adjustable part, how does it work? And what's behind that oval hole in Ti part between hub locknut/adapter and Ti.


The set up looks cool. One of those, I want it, I need it, an I gotta have it

Sent from my iPhone 4s using Tapatalk


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## Clockwork Bikes (Jun 17, 2006)

Here's another pic.


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## J. Random Psycho (Apr 20, 2008)

Oh, thanks! There's another slot!


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## dr.welby (Jan 6, 2004)

The part that looks like a trigger is a toggle to release chain tension. You flip it up and it lets the black dropout portion pivot forwards.


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## J. Random Psycho (Apr 20, 2008)

dr.welby,
thank you. It's now starting to make sense. Chain/belt tension creates force along the threaded parts, and its line follows slightly below the trigger's axle center, so that the trigger is stable when engaged but the lever arm is short enough to overcome manually.


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## TrailMaker (Sep 16, 2007)

Hmmm...

A quick release belt tensioner. The overall practicality of a belt drive system has not managed to dawn on me quite yet, but that is pretty dang slick setup regardless.


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## boostin (Apr 21, 2008)

I've had the sliders on a bike for a couple years now - they work great as long as i don't have to adjust chain tension. I like the rocker design for ease of tensioning the chain although I haven't owned one.


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## Stevob (Feb 27, 2009)

Clockwork Bikes said:


> Here's another pic.


But how do you remove the wheel?


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## unterhausen (Sep 28, 2008)

must be a through axle

On edit: I looked to see if there were any pictures of this dropout on the Paragon site. It's in the news section on the front page for now. Dropout is still under development and not for sale. I was a little amused that there is an award for "best mtb with a belt drive" category at NAHBS. I hope they got some coin from Gates for that


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## dRjOn (Feb 18, 2004)

ive been trying to work out what was going on with that drop out for days! thanks! it hadnt clicked that it was a lever for tensioning...


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## mpolka (Mar 8, 2013)

I noticed that they only offer the adjustable dropouts in Ti and stainless, I'm new to framebuilding and not very knowledgeable on welding and brazing. What is the difference between brazing stainless to CrMo and brazing CrMo to CrMo?


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## unterhausen (Sep 28, 2008)

chromo can be brazed with bronze. Stainless requires either silver or nickel silver filler


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## mpolka (Mar 8, 2013)

Thanks for straightening that out for me


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## e.gellie (May 3, 2008)

*Paragon Slider dropouts .... just be aware.....*

this is a forum for framebuilders ......? Good advice is priceless. Remember Cannondale's effort anyone? These issues aren't best answered with snappy one line responses.

If it's for yourself, try using them. Be aware the rear axle is not in line with the seatstay, not even close, so it will put a torque (lever-arm) force on both the seatstay and chainstays. Tapered stays were not designed for that torque force. So if its for a customer.... 
An improved design with these dropouts will use larger diameter stays at the rear, so we're talking constant diameter stays. They will be heavier than tapered stays. So not even close to a fishing rod, which with its taper distributes the flex and the load the material takes along its length. So this is dumb design, a backward step in my book.

So hitting a big bump while seated on the saddle when braking hard (added brakeing torque) on the rear brake and with lots of traction thrown in (most of the force goes into the frame) will put a HUGE bending load on the seatstay and be far more likely to bend them.

Like this...








Archibald Sharp wrote the book on this stuff (in 1896). Buy a Copy!! It's not usually possible to argue against his engineering calculations even though they're old. "l" in Figure 306 is NOT GOOD. He says on the next page that 1/2 inch "l" of axle rearward of the seatstay centreline increases the stress on the chainstay material in this case by 7 times!! 






.

As a fulltime framebuilder, I have only used them once, for a customer who is (thankfully still) really skinny.

The reasoning behind my reply is also why curved downtubes near the headtube are a dumb idea too..... but that's a whole other discusssion.

I just had an hour long conversation with an experienced framebuilder, and this is my effort to even things up with some advice that I hope someone finds useful.

Cheers,
Ewen


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## MiWi (Jan 1, 2013)

I never liked the offsets with those dropouts, too. A lot of unnecessary momentum for the whole rear-triangle.

That´s why I use the 2souls-cycle dropouts. 
Very little / no offset for the chainstay- and seatstay-axis and a lot of lateral stiffness.


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## TrailMaker (Sep 16, 2007)

e.gellie said:


> So hitting a big bump while seated on the saddle when braking hard (added brakeing torque) on the rear brake and with lots of traction thrown in (most of the force goes into the frame) will put a HUGE bending load on the seatstay and be far more likely to bend them. Like this...


There's not much Arguing with Physics;

Or cracks either!


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## Eric Malcolm (Dec 18, 2011)

MiWi

I like how you did your Direct Mount front derailleur....got another picture angle of it?

Eric


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## D.F.L. (Jan 3, 2004)

The 2Souls D/O looks better, generally, but check out that caliper location.


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## Walt (Jan 23, 2004)

I'd say tens of thousands of Paragon or Paragon knockoff frames says this is a non-issue if you do a decent job with your joinery.

-Walt


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## MiWi (Jan 1, 2013)

> MiWi
> I like how you did your Direct Mount front derailleur....got another picture angle of it?


Oh sorry, this is not my bike, just the next best picture I could find for those 2souls-cycles dropouts.


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## mpolka (Mar 8, 2013)

e.gellie said:


> View attachment 781848


The missing element in the frame in the bridge between the seatstay and chainstay that you find on most disc equipped hardtails. That bridge changes the profile of the bending moment across the stays. I would say that this failure was not due to the geometry of the dropouts but the lack of a support bridge. The moment caused by an offset axle is not completely negligible but the braking moment is much larger.


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## e.gellie (May 3, 2008)

mpolka said:


> The missing element in the frame in the bridge between the seatstay and chainstay that you find on most disc equipped hardtails. That bridge changes the profile of the bending moment across the stays.


I disagree; the BRACE tube is used to support a disc mount paired with a conventional dropout. Conventional dropouts do not typically have the wheel-axle cantilevered waaaay out behind the centreline of the seatstay.



mpolka said:


> I would say that this failure was not due to the geometry of the dropouts but the lack of a support bridge. The moment caused by an offset axle is not completely negligible but the braking moment is much larger.


 I disagree. "1/2 inch "l" of axle rearward of the seatstay centreline increases the stress on the chainstay material in this case by 7 times!!" That's not negligible. 
That is the key issue. A brace tube might help a little.

Are you suggesting this frame failed due to braking-forces only?

So to use these dropouts you might consider fat 7/8" chainstays and fat 5/8" seatstays then you will better resist the extra loads, but then you'd be adding extra weight and ride harshness (the feel of steel?....) to allow for a poor design.

So don't use conventional stays with these dropouts and expect them to not be way closer to failure under the customer, as they are JustRidingAlong.

View attachment 781848

My 2cents. .....university trained professional mechanical engineer and fulltime framebuilder.


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