Talbot Frameworks Tandem - Sik Fadez Family Chariot

So more updates from Talbot towers. Matt's emails never fail to take away some of the drudgery from the daily slog
This will be getting 2 sets of Rotor Flow cranks with a Paragon Machine Works yoke. 5 bolt pattern and 130bcd works with the gates whereas the 110bcd 4 arm dura ace would not.
Can't seem to find any Tandems using rotor cranks. Anyone seen one using them?

With any luck, this is kind of what the drive train will look like.

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Tubes have been ordered and this is getting started THIS MONTH after 5 months of chat. Below is the pretty much finalised geo however I'm not sure the cad programme could handle the rocker dropouts so the seat stays will join higher up the dropout giving one continuous top tube line. Matt's also managed to find some black 40H Mavic ceramic rims (for a rim brake when the eddy brake inevitably fails :)) so I'm pretty stoked about that.

75deg stoker seat tube angle. Proper track geo, she will be rapid.

she will be rapid.

Let's hope so! I'm getting pretty old these days and that refreshing 'helping hand' feeling of the stoker being of use is welcome.

when the eddy brake inevitably fails

How's this going? I had a quick look at eddy current braking as a way of adding drag to rollers, but it seemed like I'd need a huge magnet to do anything useful if the the brake rotor was only travelling as fast as the road speed (as would be the case for the surface of a roller). Magnetically braked "turbo" trainers have the periphery of the brake going at about 2-3 times the road speed, and nobody cares how heavy the rotor is so you can have 2kg of magnets spinning next to a stationary rotor/heat sink. With a hub mounted rotor of normal size, the peripheral speed is only about ¼-⅓ of the road speed. IIRC drag on an eddy current brake is proportional to velocity, so the power dissipation would be proportional to the square of velocity. With only 1/6 to 1/12 of the velocity on your tandem compared with a mag turbo, I'm sure you can see where this is going.

Not too sure how it's progressing to be honest. When I spoke with Matt early last week, he was going to send a pic but haven't received anything yet but haven't chased as he's busy with 2 other bikes at the moment. Maybe @dammit knows something?

Not a great deal, I have discussed the velocity issue with Tom- entirely inline with what MDCC_Tester is saying, the faster the braked material the more effective. On a turbo you have the OD of the wheel turning a much smaller "cog", which means that the braked mass is going like the clappers relative to the wheel.

Tom has also been experimenting with different alloys, this apparently has quite an impact also.

However that's where my knowledge runs out- I'd speak to Tom for the latest on this.

I can't recall if anyone posted the link to that training wheel which applies a braking force which the user specifies in watts? My understanding was that that used eddy-current braking in a hub-unit, which would suggest that the velocity question has an answer.

applies a braking force which the user specifies in watts?

How many watts? 100W of extra training resistance is quite different from the 1000W or so you'd want to make a tandem drag brake worth the hassle

Thar she blows!
IT'S STARTED!

Some paint has been ordered.

Who's the paint by?

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Lozzles, this project has got out of control. Reckon it might be too much? Reminds me of the 90's modified car scene.

No the paint looks lush, I was just tickled once I'd worked out what was written.

Probably still got some Max Power stickers somewhere if you want them for TT decals? :)

Max BASS

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RX7's were my thing hence the name!

In fact, here it is. Ah, the good times. Had it in storage in NZ up till a few years ago when I realised after so many years that I was never going back.

Offt, lovely. Mental Rotary goodness. I assume you dropped turbo's like barn doors in?

My Dad had an orginal '82 Rx7, I remember being in total awe of it when I was a lad, even if it did look like a black wedge of cheese.

The worst I ever got was a mk1 fiesta, in canary yellow, with an XR2 conversion. I ran out of cash so it still had the brown tweed interior and massive brown steering wheel in it :)

I assume you dropped turbo's like barn doors in?

Ha, unfortunately not. I was all about keeping it original as possible. Was a member of the Wellington chapter of MREC and went to a few track days with it! So regret selling it! Wouldn't mind a S6 however need a place with a garage first!

did everyone in the land of the long white cloud call you Svin?

You'd def need a dove in the garage for an S6, as weren't they the problematic imports?

Anyway, lovely cars & mental engines.

Now, about those 90's tribal tandem decals.....

Paint test by Matt. The paint (and prepaint prep) needs to be absolutely flawless on this. Luscious, with a huge shine, absolutely no inclusions or orange peel and dripping clear coat as per the tank pic above. The quality of the paint is the one area I'm really worried about with this so Matt is sending me out a piece of tube painted.

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