Author Topic: N-1 RIP*, welcome N+1  (Read 1072 times)

N-1 RIP*, welcome N+1
« on: March 26, 2020, 05:05:41 pm »
I posted with pleasure almost 4 years ago about our new shiny Orbit Lightning Titanium.

https://yacf.co.uk/forum/index.php?topic=98001.0

It was one of a small batch of frames that JD Tandems bought in but a number of these have suffered cracking around the bottom bracket.  To their credit they offered to replace all of the batch with replacement frames at their cost under guarantee.

So this is our replacement frame that we collected over the weekend in a hurried trip up to North Yorkshire, built up with all the original components .

DSC01986 by Russell Wiles, on Flickr

It's a Bob Jackson Orbit Summit Sapphire Pro in mainly Reynolds 853 (with 2 S&S couplings that we paid for) in Ruby Flam.  Bob Jackson's workmanship is superb and the service from John and Ruth excellent.  We've only had a short shakedown ride so far in high winds but it feels great.  A comfortable soft ride but very stable.  We look forward to many more miles on it.

* Rest in pieces as it has gone for scrap.

Russell

Re: N-1 RIP*, welcome N+1
« Reply #1 on: March 26, 2020, 07:43:21 pm »
What's that frame design called?  Normally there is diagonal bracing from the head tube to the rear BB, with the front seat tube piercing it.
And Darkness and Decay and the Coronavirus held illimitable dominion over all.

LittleWheelsandBig

  • Whimsy Rider
Re: N-1 RIP*, welcome N+1
« Reply #2 on: March 26, 2020, 08:18:49 pm »
Generally known as 'open'. The most common tandem frame design now is 'direct lateral' (head tube to stoker BB) but previously the most common was 'marathon' (headtube to middle of stoker seat tube, usually with additional stays). Before that, it was 'double diamond' (captain's seat clamp to stoker's BB).

There are all sorts of less common variations including 'double marathon' (direct lateral + marathon) and 'uptube' (captain's BB to stoker's seat clamp, with or without a marathon tube). The least structurally efficient tandem design was ‘twin laterals’ (paired small tubes from head tube to rear axle).

Fewer S&S couplings are needed for an open frame (so cheaper) and a bit lighter and plenty stiff enough with suitably oversized tubing. In the past, only plain gauge large tubes (generally heavy) were available and connecting large frame tubes to 1" head tubes, 1 1/8" seat tubes and standard BBs was problematic anyway.
Wheel meet again, don't know where, don't know when...

Re: N-1 RIP*, welcome N+1
« Reply #3 on: March 27, 2020, 11:40:08 am »
I cannot comment on the compared stiffness of direct lateral vs open, and I think no one has ever conducted any serious testing. However, the good point (for us) with lateral design is that you can fit many more bottle cages, six for us. Six bottles might sound enormous, but it's just three per crew member!

A

LittleWheelsandBig

  • Whimsy Rider
Re: N-1 RIP*, welcome N+1
« Reply #4 on: March 27, 2020, 11:56:10 am »
I cannot comment on the compared stiffness of direct lateral vs open, and I think no one has ever conducted any serious testing. However, the good point (for us) with lateral design is that you can fit many more bottle cages, six for us. Six bottles might sound enormous, but it's just three per crew member!

A

FEM is commonplace and I remember reading about strain-gauged frames in the lab and on the road to calibrate FEM at sporadic intervals over the past 35 years or so, mostly for solo frames but at least two times for tandem frames since the '90s.

That is a lovely looking machine, by the way.
Wheel meet again, don't know where, don't know when...

Re: N-1 RIP*, welcome N+1
« Reply #5 on: March 27, 2020, 05:04:24 pm »
There is provision for 4 bottle cages and John has developed a bracket for another under the stoker stem.  The stoker cage shown is not as convenient as it would be in a lateral design but still usable.

Only done 26ml so far, did a short ride this morning for our 'exercise', and it feels very nice.  Smooth, stable and stiff.  The titanium one just felt a little less somehow.  It is about 8lbs heavier but does have 2 S&S couplers which adds a couple of pounds if I remember correctly.

Thank you LWB!

Re: N-1 RIP*, welcome N+1
« Reply #6 on: March 28, 2020, 06:45:37 pm »

It's a Bob Jackson Orbit Summit Sapphire Pro in mainly Reynolds 853 (with 2 S&S couplings that we paid for) in Ruby Flam.  Bob Jackson's workmanship is superb and the service from John and Ruth excellent.  We've only had a short shakedown ride so far in high winds but it feels great.  A comfortable soft ride but very stable.  We look forward to many more miles on it.

Very nice.  We have one of these on order, ours is due end of April-ish and last I heard from Ruth its on schedule but things are changing fast.
Ours is in a light metallic purple colour, 2 couplers.  Looks like yours has the same rack as ours. Ours will have a telescopic suspension s/post  but I have a thudbuster seatpost at home (may need a shim).  We went for a 50/34 double chainset. Did you spec the braces on the brake bosses ?

Re: N-1 RIP*, welcome N+1
« Reply #7 on: March 29, 2020, 05:55:58 pm »
Hi sg

The rack is a Topeak MTX Uni Explorer or something similar.  Yes it has a Thudbuster ST.  Not sure what you mean by braces on the brake bosses, but the V brakes are Avid Arch Rivals and anything odd you might see on or around the rear V brake is a Basta Click 3 lock.  Bob Jacksons added some braze-ons for it to sit on.

R

Re: N-1 RIP*, welcome N+1
« Reply #8 on: March 30, 2020, 07:40:39 am »
Hi R,

I was looking closely at your photo, since we are very interested in this sort of machines, and it seems that you have two brake/shift levers + 1 bar end shifter. So you have 3 gear controls? Maybe the bar end shifter is there for another purpose?

A

Re: N-1 RIP*, welcome N+1
« Reply #9 on: March 30, 2020, 11:23:47 am »
The bar end shifter is a parking brake, could be a drag brake, that operates the rear V brake.  This is standard JD, Orbit, practice.

So V front, disc rear for main braking and 3rd, parking brake, on bar end.

One day when the world starts up again we'll come and see you with it, you are near Limoges, no?  We have a house about 1h NE of Limoges.

We were going to the international in Salviac but maybe that'll be next year now.

Re: N-1 RIP*, welcome N+1
« Reply #10 on: March 30, 2020, 11:52:15 am »
One day when the world starts up again we'll come and see you with it, you are near Limoges, no?  We have a house about 1h NE of Limoges.

Depends on what you call "near"! We are close to Nevers, 3h NE of Limoges, so probably 2h from your house. Anyway, when we will see the end of the end of the world, we will be more than happy to meet you, wherever you are!

A

Re: N-1 RIP*, welcome N+1
« Reply #11 on: March 30, 2020, 12:12:17 pm »
Yeah, Mr Google says just over 2h to Nevers.  Who is it that is SSW of Limoges then??  ???

Edit:  mzjo of course!

Re: N-1 RIP*, welcome N+1
« Reply #12 on: March 30, 2020, 12:26:47 pm »
Probably Mr Asterix, but I think he doesn't live there anymore. If I remember correctly, Mr Mzjo also lives somewhere near Limoges.

A

guidon

  • formerly known as cyclone
Re: N-1 RIP*, welcome N+1
« Reply #13 on: March 30, 2020, 06:42:21 pm »
the international is still going ahead at the moment, although many other events have been postponed.... Salviac still sends a shudder (I used to go there several times a week, small narrow roads - not that easy in a hgv....

321up

  • 59° N
Re: N-1 RIP*, welcome N+1
« Reply #14 on: May 10, 2020, 07:37:46 pm »
I cannot comment on the compared stiffness of direct lateral vs open, and I think no one has ever conducted any serious testing. However, the good point (for us) with lateral design is that you can fit many more bottle cages, six for us. Six bottles might sound enormous, but it's just three per crew member!

A

One of the machines that we test rode at The Tandem Shop some years ago was an 'open' geometry with very oversized tubes.  Felt great to ride, no flex.  We went for a Landescape direct lateral on the assumption it might be more reliable.  My thinking was that a direct lateral has a bit more redundancy in the event of a failure.  We are very pleased with our Landescape, it's still going and we bought a second one before the move North curtailed our Audaxing (still riding and not had to build it up yet).  Russell's Bob Jackson looks great, given that the relatively short seat tubes and it being steel I am confident that they will have many years of fun on it.

A.

Re: N-1 RIP*, welcome N+1
« Reply #15 on: May 10, 2020, 08:17:52 pm »
...So this is our replacement frame that we collected over the weekend in a hurried trip up to North Yorkshire, built up with all the original components .

It's a Bob Jackson Orbit Summit Sapphire Pro in mainly Reynolds 853 (with 2 S&S couplings that we paid for) in Ruby Flam.  Bob Jackson's workmanship is superb and the service from John and Ruth excellent.  We've only had a short shakedown ride so far in high winds but it feels great.  A comfortable soft ride but very stable.  We look forward to many more miles on it.

Lush. Fabulous colour and so nimble-looking due to the lack of additional tubes. Much prettier (IMO) than the ti one.

I need a tandemming partner. And a tandem.
L'enfer, c'est les autos.

Morat

  • I tried to HTFU but something went ping :(
Re: N-1 RIP*, welcome N+1
« Reply #16 on: May 11, 2020, 02:10:04 pm »
Gorgeous!
My steel half-bike is 853 and I love it. So comfy yet never dull.
Congratulations :)
Tandem Stoker, CX bike abuser (slicks and tarmac) and owner of a sadly neglected MTB.

Re: N-1 RIP*, welcome N+1
« Reply #17 on: May 11, 2020, 06:26:00 pm »
Thanks for your kind words.  We have done a few more miles now and will be able to get out for longer rides soon as well (thanks Boris) and it still feels nice.  I've fitted a slightly shorter stem as I felt a little stretched (as I did on the other one) and we are both very happy.

Fitting in a shop with our daily exercise we came back with 2 panniers worth of shopping including 4 pints of milk and 6 cans of pulses amongst other not so heavy items.  No idea of the all up weight but each pannier was very heavy to lift.  The bike didn't notice it a bit.  Very pleased.