# Anyone knows what make is this frame?



## [email protected] (Dec 2, 2006)

Thanks.


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## Speedub.Nate (Dec 31, 2003)

Wow, so somebody did make a URT tandem! That's one step closer to a tensioner-less Speedhub installation.

So... what's the story behind that picture? Scary looking unsupported down tube & stoker seat mast. I wonder how they intended to tension the timing chain.


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## sparrow (Dec 30, 2003)

That's gotta be "home made", odd bike.


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## MartinS (Jan 31, 2004)

I'm guessing it's some oddball Euro bike - if not a homemade job. I was in Austria in the spring and couldn't believe the number of URT variations still available, although most are used purely for commuting, and really odd frame designs that looked pretty frightening.


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## Speedub.Nate (Dec 31, 2003)

The web address on the frame, www.kailai-frame.com (and its derivatives) are all invalid, but I did find a listing for Shanghai Kailai Bicycle Frame Co Ltd. in Shanghai. There is contact info if you follow the link.

http://www.ig-cn.com/ige/member/STAINDEXSEQ_COMPANY!30.HTML


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## [email protected] (Dec 2, 2006)

Thank you all! I decided not to buy this frame, it is weak as you said.


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## TandemNut (Mar 12, 2004)

So Nate, 
What with current shock technology being what it is, I've been thinking that a URT tandem frame might work now. Solves lots of problems for Rohloff and SS setups. My past experience with URT's is that the pivot point would have to be ar or as near the bb as possible. A swingarm pivoting around the bb would likely be best, such as the old Gazelle frames (local builder), and, I think, Rotec use to make a similar setup. What do you think?


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## Speedub.Nate (Dec 31, 2003)

BigNut said:


> So Nate,
> What with current shock technology being what it is, I've been thinking that a URT tandem frame might work now. Solves lots of problems for Rohloff and SS setups. My past experience with URT's is that the pivot point would have to be ar or as near the bb as possible. A swingarm pivoting around the bb would likely be best, such as the old Gazelle frames (local builder), and, I think, Rotec use to make a similar setup. What do you think?


The "problem" with solo URTs is one the new generation of shocks can't solve: when the rider stands -- all the weight is on the cranks -- the suspension effectively locks out. So the question is, what happens on a tandem? The captain's weight remains on the frame, whether standing or sitting. The stoker, when standing, will still have a great impact on the loading of the rear end, but not as great an impact as on a solo bike. So if the stoker removes weight from the saddle on a rough descent, the suspension effect disappears.

You've also got some pedal feedback to deal with as the suspension cycles, which will be transmitted through the drivetrain.

If you could get a swingarm pivoting around the bottom bracket (similar to a Kona or Lenz), the lockout problem would go away. I don't think the bike would truly be a URT at that point, even if the BB shell remained connected to the rear triangle.

I'd like to take it a step further, using Haro's hybrid URT-Linkage suspension design.


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