# Alternative to Ritchey and S&S coupler systems



## bee (Apr 7, 2008)

Ran across this design a little while ago. This sort of newish design has been implemented by some builders already on the drive-side seatstay of some belt-drive frames. This is the first I have seen of a builder doing something similar on a main tube.










Click here for a bigger image. The picture shows the coupler on the top tube.
https://www.cycles-for-heroes.com/sites/default/files/neuigkeit/FI-coupler-prototype.jpg


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## 18bikes (Jan 15, 2007)

The pic isn't working for me, but the one in the link looks to be on a seatstay. I would have thought a coupler of that size, unless it's had a lot of maching work done would weigh a ton

Matt


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## TimT (Jan 1, 2004)

That's not a frame coupler but a pass through for a belt drive belt. Its something like 49 British pounds available through Ceeway only. only fits 16mm set stays. It would be nice if Paragon would make some thing similar for 19mm stays.

Tim


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## customfab (Jun 8, 2008)

TimT said:


> That's not a frame coupler but a pass through for a belt drive belt. Its something like 49 British pounds available through Ceeway only. only fits 16mm set stays. It would be nice if Paragon would make some thing similar for 19mm stays.
> 
> Tim


Paragon does the 'mod' dropout. It's just a slider with a bolt on plug for the drive side seat stay.


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## Plum (Sep 14, 2004)

I think there's couplings like that available for roll cages, might look for a source there. Weight is likely to be pretty high, as they're designed to hold up for impacts, rollovers, etc, not for light weight applications.

Offroad or road racing tubing sources would probably know who makes them..

Plum


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## surlytman (Nov 9, 2005)

DeNunzio Fabrications makes another kind of Keyed Coupler

http://www.denunzioracing.com/shop/denunzio/tubecouplings.html

Limited in sizes but you get the idea. I grabbed this info off of the Landracing.com message board


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## Jehoshaphat (Mar 18, 2011)

Those look very heavy. 

I don't think they are a very good idea for breaking a seat stay on a belt drive bike, especially on something that's going to be bouncing off of rocks (not that it won't work, it's just adding a weak spot to a heavily stressed tube and I would rather avoid that). 

I've got an idea for breaking the rear triangle that might be stronger but still not ideal and not light either. 

Breaking a full size tube in the main triangle is more critical than breaking a stay in the rear triangle. A coupling that is light, strong and stiff just isn't going to be cheap.


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## bee (Apr 7, 2008)

Oops. It actually does look like that coupler is on the right seatstay. You can't actually see the other seatstay from the picture, so the tube still may be a top tube. However, looking at it again it does appear that it is the right seatstay.

Ceeway sells this particular coupler for belt-drive systems, which they call also call a splitter as well as a coupler. Splitter or coupler or whatever you call it. That would be splitting hairs (no pun intended). It is joining two tubes together, and can be used theoretically in a coupling application to join two tubes together.

Here is a PDF of the coupler, and it is titled "coupler" at the top of the page by the manufacturer, on the Ceeway website.
Note: the part in the middle is held together by two bolts.
http://www.ceeway.com/acrobat%20files/Belt%20Drive%20Coupler.pdf


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## nightofthefleming (Jun 14, 2009)

that ceeway "coupler" is the same as the one as the first photo you posted in the link


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## bee (Apr 7, 2008)

nightofthefleming said:


> that ceeway "coupler" is the same as the one as the first photo you posted in the link


Yeah, it sure does look that way. Looking at the top pic from the link, you can just barely make out the bolts holding the middle part to the ends.


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## TimT (Jan 1, 2004)

I have one. Came in last week. Its pretty light as the center is made from aluminum and the steel pieces are hollowed out. Its keyed so I'd run it off road. Still on the fence about using it as my original design called for 19mm stays. I could change it to 16mm as the bike I'm on now has 16's. I'm not to comfortable about bending a stay (like with the PMW design) every time I need to change the belt. I might reverse engineer it for 19mm and make one. IDK like I said I'm pretty busy at work and kids so got a lot on the plate. Might be easier to switch to 16mm stays.

Tim


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## Jehoshaphat (Mar 18, 2011)

"Bending" a stay enough to get a belt through isn't what I would worry about, the deflection is not anywhere near the plastic deformation point of steel (aluminum would be a different story).

Fractures and bends always have a starting point and that's a stress riser. As strong as a coupler looks or feels, it probably concentrates stresses somewhere and will probably be weaker than a contiguous tube. 

Even a very carefully designed coupler will have that issue, but theses especially look risky because they are not ~symmetrical around the long axis of the tube.


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## TimT (Jan 1, 2004)

http://www.paragonmachineworks.com/...ineworks/dept/271366/ItemDetail-10525861.aspx

I have a similar tube splitter ,like the PMW in the above link, on my currant belt drive bike . You really have to pull the tubes apart to get the belt to pass. IDK I've straitened enough frames to think this is not a good idea. I like the window idea. just not the 16mm part of it. Like I've said I'm on the fence, The bolt on stay at the drop out might be better then the middle of the tube but there is the whole bending thing going on again.
For what its worth I have one of those drop outs and frame end sitting on the bench also.

To many projects right now to focus.

Tim


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## Jehoshaphat (Mar 18, 2011)

Near the seat tube or near the dropout seem like the best spots to me if you are going to break the seat stay, but the brake bridge may keep you away from the seat tube. 

My idea is to break the chain stay near the bottom bracket, that way the whole seat stay and most of the chain stay can flex to give that belt clearance and the size of the coupler can be bigger. Now I just have to wait until I can get to that project and mill the pieces. 

There is no perfect solution, just different compromises with their own set of tradeoffs.


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## TimT (Jan 1, 2004)

Bad idea to break the chain stay as any flex in the stay will cause the belt to pop. Basically through my own test and others who have confirmed it. The belt starts to ride up out of the grooves of the rear cog and then get snapped back in place. Best to go with the stiffest stays you can.

Tim


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## Jehoshaphat (Mar 18, 2011)

Maybe, I've been known to do some stupid things. 

I'm not afraid to take a risk. I have an idea that should be very stiff, if it doesn't work I'll have a shitty frame. That's not the worst thing that has ever happened to me.


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## illcomm33 (May 10, 2006)

*Not worth the trouble?*



TimT said:


> Bad idea to break the chain stay as any flex in the stay will cause the belt to pop. Basically through my own test and others who have confirmed it. The belt starts to ride up out of the grooves of the rear cog and then get snapped back in place. Best to go with the stiffest stays you can.
> 
> Tim


Tim,
I have cracked chainstay and was wondering if now is the time to give a splitter a chance.  Rody provided some good guidance on a/the best technique the fix the issue but someone was asking me why I don't use a splitter to fix it. I had a feeling it would be the durability of the splitter/stay but didn't know for sure. (which is how I found this blog).

What about the new center-track belt drive. Would that help with the riding up issue? 
Either way there is a link to how Rody fixed a similar seatstay issue that many might find valuable.

Thanks all!

http://forums.mtbr.com/frame-buildi...t-way-repair-775776-post9112836.html#poststop


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## tamen00 (Mar 10, 2004)

My question seems to apply to this thread... are there any alternatives to S&S or Ritchey systems? Or, is there anyway that a hobbyist can get a hold of the Ritchey or S&S system? I can not find them anyplace - and they will not sell directly to me. Thanks in advance for any sources or tips (lbs was not able to get them either)


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## Walt (Jan 23, 2004)

*S&S used to sell to hobby builders*

They used to do a thing where they would sell one set (just one, ever) of S&S couplers to hobby builders for their own personal use. You might call them and ask.

Also, I think you could make your own version of the Ritchey system pretty easily - look for my post from a few weeks ago about this, Welby had some good ideas.

-Walt



tamen00 said:


> My question seems to apply to this thread... are there any alternatives to S&S or Ritchey systems? Or, is there anyway that a hobbyist can get a hold of the Ritchey or S&S system? I can not find them anyplace - and they will not sell directly to me. Thanks in advance for any sources or tips (lbs was not able to get them either)


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## tamen00 (Mar 10, 2004)

Thanks for the info Walt!!! I was following the other thread from a couple of weeks ago... but missed a bunch of posts in the middle! It has all the info I was looking for - Thanks!!

(BTW - S&S would not sell the couplers to me... I will re-ask and be a little more clear that I need one set for personal use and see what happens)


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