OK, here goes...

Having now had a fun few weeks with my 'tester' ti 29er made by ti-bike's inimitable PORTER (that's for anyone who's ever has or ever does contact him ) I'm now starting to draw up plans for an uber-bikepacking ti 29er tandem for the 'Franciscan Trail' and similar ecapades over the next few years. 'Home for two' for at least a month at a time..

The outline spec is: ti, 29", S&S couplings, rigid. Everything else - components, attachments, lighting, stowage etc. etc. etc. is still TBD. So, before I commit to some somewhat costly Chinese ti chopping & sticking, be they weird, wild, wacky (or even just why??!!), I'd be most grateful for any suggestions/comments this esteemed gathering may choose to offer/make

Thanks in advance...

That, Roy sounds highly mad, it's the maddest thing I've heard in a while ... I salute you, it might be mad but it's also a fantastic thing to build :D

Sounds bonkers, nice one 8-)

My only question would be why a tandem? Not looking to rain on anyone's parade and an answer of "because we can" would be reason enough but curious about your choice.

My ex and I rode a Dawes Double Edge 26er mtb for several years and it's the best fun I ever had on two wheels. Off road it kept getting pinch punctures on the front until I fitted suspension forks which transformed it into a very useable machine (you can't lift the front end at all). You have had one on test so you will know if you need them on a 29er. A stoker who sits stock still is a godsend especially off road. We used some basic commands to make things easier, "stop" stop pedalling, "go" start pedalling, "stand" stand up with pedals level as we are crossing rough stuff, "drop" we are going over a drop off, "change" slacken the pedalling whilst we change gear, "brake" we are about to brake hard. For the stoker i fitted high rise bars which gave them a much better view and also the plushest saddle I could find mounted on a suspension seatpost as stokers tend to get a bit of a battering. As I was a lot fitter than my stoker I also had my cranks set slightly ahead of theirs so that as they reached the top of the stroke (the hardest bit) I was already on the downstroke so helped pull them over. Most memorable moment was mixing it up with a bunch of bikers coming down Whinlatter Pass in The Lakes. They attempted to overtake but found their speed was no greater than ours on the twisty road. We where all grinning like Cheshire cats at the bottom and they all gave us a big thumbs up and a cheery wave as they sped away. I am very, very jealous, you will have great times on it.

'Why Tandem?'

Some background; Mr B & I have been riding tandems on & offroad for about 15 years (current is http://flic.kr/p/dPeXAy) mainly because 2 seperate bikes don't work for us touring - I'm 6' & she's 5'4 so the best way to keep together was ride one bike. It also means 1 of everything bike-wise shared between two so only 2 tyres to worry about flatting, 1 set of gears to keep shifting etc etc.. and it keeps the shared weight down (a tandem is 'only' a bike with a couple of extra tubes & a crank between the front & the back after all)

Cheers Ray.. tandems indeed massive fun & we've surprised quite a few people with how agile they can be offroad. Brilliant in mud and long, slow uphills where the power of 2 and big gearing winches you through or up when everyone else is having to get off or fall off. Also can be bloody fast; On l'etape some years ago was overtaken on a downhill by one doing - 60K maybe - I must have been doing at least 40. The bike had a trail of singles behind it all slipstreaming. Went by like a train - and sounded like one too. Just had a moment to notice that the stoker was a big lad with prosthetic limbs below the knee!

Cheers for explaining. Interesting stuff 8-)

Sounds like fun.. But I would be wary of chinese ti companies for a tandem - they make some good enough frames but unless either you or they have a lot of experience in that area, can find the right tubing and communications are very good, it could be an expensive experiement.. Even if it was a steel UK-made bike like a Longstaff the power-to-weight advantage of a tandem is still there and the chances of it being a brilliant ride are higher.
I'd also consider a Jones-style 135mm width front fork/hub, from experience the added stiffness it gives a 29" wheel would be useful on a loaded off-road tandem.

Cheers James, all valid caveats. As I and many others have done for for various custom ti frames, I'll be using http://www.ti-bike.com. Apart from the need to be absolutely specific about what you want them to make - literally to mm accuracy, which they deliver - and Porter's idiosyncratic email style (but then my Chinese isn't exactly fluent! ), I've found ti-bike are very responsive (sometimes a problem with Chinese firms) and make an excellent product. Given this, the onus is very much on the designer (me in this case) to get it right.. risky yes, but a good challenge too

The outline spec is: ti, 29", S&S couplings, rigid.

Will you be using one of their Ti Truss forks? ... they look very nice

I was looking at those forks too, I see they also do a jones style bar, very nice.

Truss forks might be a possibility (odd forks for an odd bike) but question is how best to 'pack' the front end. I suspect the obvious way with Jones-style forks - stuffing bags into them - probably doesn't allow them to 'work' properly. (If anyone here has any experience on that score, would be good to have..) Also seems the jury is out on whether they work better than steel. (Again comments?) The Bars might be on the cards too (big points in any 'wierdbike' competition ) though I run Marys at the moment & really like them..

Having looked at that site you can get the whole Jones-style set up. I wonder if theirs has a normal front hub/headset arrangement. And if it costs less than £3800.....

Porter's outfit will basically build whatever you want. So, if you choose to (ahem) 'copy' someone else's design they'll make it. But, big caveat, they're not cycling engineers, so you have to get the design right - Porter will make suggestions (well, more like NO! CAN NOT DO!) but I suspect that's more to make things easier (read less costly) at his end rather than to sort out any 'error' you might have made in the design. That's your problem... & one of the things I find exciting about working with ti. It's a bit like Russian roulette,they give you the gun but you bring the bullet & pull the trigger :twisted:

First rough is now up;

http://flic.kr/p/dYicrU

Observations welcome

Looks well Roy, I'm liking the tapered downtube, it'll look lovely in Ti.

One thing I've thought about lately and something I'd include no matter what I were having built would be the required clearance to run the next generation 29" tyres, ie 3" wide. I know there's only Surly at present but I can see others following suit over the next couple of years.

Hats off to you for deciding to do this! Just wondering if you looked into any of the Russian custom builders as well?

EDIT: Oh, if you use meths you should have one of the tubes made as a fuel canister...a bit like Mike Curiak's Snoots!

Cheers all.

On 3" tyres; Definitely something I'm thinking about. The front is no problem as the fork design can be made to accommodate 'almost anything'. The rear is a bit more of a problem - quite a bend in the stays & right now I've not got enough references of how best to do it to go to (and nothing in the shed with 3" tyres to measure - knowing how notoriously bad tyre manf. are about their actual sizes, I like to have the real thing in my hands before I start putting down specs in metal!) but, I'm looking

Internal cannister is a monster idea, forgot that one. (Maybe a little 'hip' flask in the top tube too )

Looked briefly at the Russians, but as I've had good work out of China so far, that's my go-to for the moment. May change though when I start to get responses from there to the drawings - one drawback of the Chinese shop is that they don't (appear to) ride. That's definitely one advantage of going to to US Ti guys... but then you (rightly) pay for their years of experience which makes doing something like this (for me) prohibitively expensive

Latest revs now at: http://flic.kr/p/e8Quzn (Brakeside with full compliment of bottles) and http://flic.kr/p/e8W8S1. (Driveside showing potential framebags.)

Lots of things still in flux;

Brake mounts & dropouts – I’m looking to include BOB trailer bolt eyes behind the dropouts which, taking into account a Rohloff shifter box, brake mounts & brake too, make for a lot clearances to juggle with. (Not yet convinced about this as a solution on the basis that 'it's not right if it don't look right'...)

Cable/tube guide positions - facility for both Rohloff & standard gears for ‘just in case’ scenarios. These might go back onto the top.

Multiple bottle / internal bag mounts (ta BRP's super-sorted English for that)

An integrated rack on the forks..

Headtube dia.. still not sure if it's a better to go with 'massive' & fit oversize/undersize headsets depending on the steerer or stick to a more 'standard' that will take just 1.1/8 - the size that's worked fine on my Ventana so far..and may be better to have in 'parts where Chain Reaction doesn't deliver' (tho I doubt there's anywhere left on the face of the planet on that score!)

As always, comments welcome..

royAB wrote: Multiple bottle / internal bag mounts (ta BRP's super-sorted English for that)

Just be very careful with the position of the two mounts nearest the headtube! :D

I wish I'd set mine just a half inch further back...I can JUST get those bolts in if I use my topeak micro ratchet. :D

Thanks BRP, was thinking about that as I roughly scribbled in the points.
(Another thing to add to the 'real world mockup' phase of this project)

For reasons various, the ti- part of this project may have to become fe- (well maybe not iron, but steel). Having never had a custom bike made here, I'd welcome any suggestions as to a frame builder in the UK who'd be up for a bit of a challenge..

Matt at 18 bikes in hope is always up for a challenge. I've seen a few of his frames, all understated beauties!

For Titanium who works with a great frame builder who's over sea's contact Michael Travers at http://www.traversbikes.com/ he's a bit of a frame designer addict

Disappointed, thought the end result may be posted up : )
Do Travers use XACD, same as royAB's original plan? Maybe not, a fair number of the smaller ti brands do.

Steel custom tandem - Longstaffs possibly. Website seems to be down at the mo. I'd go with a builder who's made them before for experience with suitable tubes and Lance there is a really nice guy who knows his stuff.