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  • SuDiBe Tandemseiten - Literatur
    teams for an exciting race you ll need to advertise early and provide the opportunity for meaningful competition Prize list and entry fees should be comparable to your other small fields such as juniors women or masters Tell Them About the Race Start early Competitive tandem teams are not numerous but they are more willing to travel when they have time to prepare Advertising to the tandem community is critical to a good turnout but prices range from free to cheap Check out the links section on the TrueSport Tandem page Turn Up the Heat Tandems will travel if you have a multi day event with a mass start event and decent distances We had 14 18 teams attend our 3 day race each year They came from all over the Midwest and even New Hampshire You can expect fewer teams unless you have a solid multi day event Leverage your race as prep for National Championships or the Burley Cycling Classic Tandems handle well in criteriums and road races We had a seven corner criterium and plenty of hills They loved it Gender Categories We had a single tandem field with both Male and Mixed teams racing together We had 3 place bonus awards for the top mixed teams Mixed teams typically like to have their own competition and there are many many more mixed teams than male male teams Tandem categories work the same as single bike categories Like most women s or master s races all categories tend to be lumped together Tandem teams may include either blind or sighted stokers Blind and sighted teams compete head to head with no problem If you are not familiar with the U S A B A check out em out United States Association of Blind Athletes Safety If you

    Original URL path: http://www.sudibe.de/articles/tandemrace2.html (2016-02-09)
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  • SuDiBe Tandem Site - Literature
    since a lot o f you seem to be enjoying this thread here s a further portion of my instructions to new tandem riders My test ride sequence includes a short ride with the each customer I always ride with the prospective stoker first and 98 of the time this is the wife girlfriend During a pleasant ten minute ride I make it a point to warn women guys develop bad habits while riding single bikes After we ve finished her test ride it s his turn to be my stoker I ask her to stand by and watch while we get started After repeating the basic here s how the captain gets on the bike demonstration I gave ten minutes earlier I tell him he must get on the same way his wife did earlier by p utting a foot on one pedal and swinging the other foot directly onto the opposite pedal like getting on a horse When the husband is totally clipped in if he s wearing cleated shoes I ll insist he lock in I ask him to raise the left pedal halfway for me As soon as the pedal is cocked I turn to his wife standing next to us on the curb and say Remember how I warned you that guys develop bad habits from riding a single bike As she nods I raise my left foot to the pedal and slowly start to lean the bike to the right I don t know why I state as the bike leans further but for some strange reason guys always want to At this point I m usually interrupted by frantic movement from a panicked stoker who more often than not has managed to free his right foot and plant it on the ground I calmly turn to him and say Stokers are supposed to leave their feet in the pedals go ahead and clip back in I won t drop you After he hesitantly reholsters his foot I turn back to the wife and continue from the beginning Remember how I warned you that guys develop bad habits from riding a single bike She smiles as I again start to tilt the tandem towards my right foot By now she understands my joke and struggl ing to control her composure while her husband fights panic on a bike that s leaning ever further earthward I don t know why I continue but for some strange reason guys always want to lean a bike waaaayyyyyy over before they start to ride And if you re the stoker it feels like the captain is going to drop you But you shouldn t worry when he does this to you and he will do this to you it only FEELS like he s going to drop you Of course I didn t do this to you when you were on the tandem because there s a technique a captain can use to get started without leaning the

    Original URL path: http://www.sudibe.de/articles/propmethod.html (2016-02-09)
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  • SuDiBe Tandemseiten - Literatur
    where doubled power reduces the significance of these advantages by 50 So what did we learn during Santana s testing Our panel of testers uniformly found 700c tandems were more stable at higher speeds Most testers also believed the tandems with 700c wheels were faster The difference in feel was substantial enough so that an envisioned follow up blind test with carefully shielded from view wheels was deemed unnecessary Why were 700c tandems clearly more stable At the time of the testing none of us had a clue I later developed a theory first published three years ago that the answer was due to the shape of the tires contact patch footprint If the same mass is supported on tires inflated to the same pr essure the area of the contact patch must also be the same this is after all the meaning of p s i or pounds per square inch The difference in wheel diameter causes the footprint of the bigger wheel s tire to be more elongated than the footprint of the tire on the smaller wheel I reasoned a longer footprint would provide greater directional stability at high speeds as is the case with longer skis surfboards and skates Until someone comes up with an alternative explanation this theory not only explains the increase in high speed stability it also explains why off road riders might reasonably prefer 26 inch wheels the rounder footprint provides less steering resistance and easier maneuvering at low speeds While my original footprint theory explained stability it didn t explain the perceived difference in speed I originally thought it probable our testers were mistaken about a speed advantage for 700c wheels If they actually rode faster with 700c wheels I felt certain it was an ephemeral result of enhanced rider confidence Put simply if riders on 700c test tandems felt more confident at higher speeds because of stability resulting from the shape of the footprint this confidence might allow a temporary increase in performance If there was an enduring speed difference it seemed likely to me the lighter and smaller 26 wheels would have the advantage Some of you might think the difference in diameter between 26 and 700c is too small to matter Actually even though we all know 700c rim is slightly smaller than 27 rim a 700c rim is a full 2 1 2 inches larger than 26 rim Two and one half inches How can difference between 26 and 27 exceed 2 1 2 Answer a ridiculous tradition dictates that sizes of bicycle wheels unlike car and motorcycle wheels indicate the nominal outside diameter of the TIRE and not the actual diameter of the rim While the out side diameter of a traditional 26 inch balloon tire is about an inch smaller than the original 27 inch racing tire the rim is nearly 3 inches smaller The same tradition exists in Europe where there are no fewer than 4 diameters of rims that accept 650 tires labeled

    Original URL path: http://www.sudibe.de/articles/700-26.html (2016-02-09)
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  • SuDiBe Tandemseiten - Literatur
    in removing a chain to clean it the result is an increased incidence of chain pull apart I also don t believe in bathing the chain in solvent it flushes out the original factory installed lubrication Because high priced motorcycle chain lubes were developed to stay in place at high r p m they re too sticky for bicycles I also generally distrust clean lubes usually paraffin based environmentally friendly lubes repackaged salad oil and penetrating rust fighting lubes which contain non lubricating solvents and acids While there are probably dozens of suitable lubes Tri Flow works fine for me Did I get off track or what Timing chain tension At the Santana factory we start with too tight an initial chain tension so our customers won t have to adjust the chain when it takes its initial break in stretch within 20 miles After a timing chain has taken its initial stretch it should probably be oiled and adjust ed every 200 300 miles What is the proper adjustment As tight as possible without binding Because most chainrings aren t perfectly concentric as you rotate the cranks tight and loose spots are normal Thus the oft repeated measured slack method of adjustment is not only messy it s impre cise Instead without ever touching the chain I simply adjust the eccentric to where the chain vibrates like a lightly plucked guitar string while backpedaling through the very tightest segment of the chain s rotation If you want to verify the accuracy of my method derail the rear chain to check for binding On newer Santana tandems we ve gotten the eccentric and housing tolerances exact enough to allow the following near automatic adjusting sequence requires no trial and error takes less than 60 seconds First rotate the cranks to the loosest part of the rotation where the chain droops the most After loosening the two eccentric grub screws one full turn each use a pin wrench to rotate the eccentric and snug the chain Finally backpedal a half dozen complete revolutions and then retighten the two grub screws Because a too tight chain will rotate a loose but not wobbly eccentric backpedaling will automatically rotate the eccentric to its optimal position Warning to those who contend it s too much trouble to tighten a sagging timing chain A too loose chain can not only jump all the way off much worse is when it jams while coming only part way off This will generally happen during a stand up sprint when frame bowing creates just enough additional chain slack to allow the timing chain to mistrack by a single link This is an experience the two of you will never forget when the drivetrain locks up your spin rate instantaneously drops to zero If you re lucky you ll only fold the chainring dump the chain and stay upright If you re extremely unlucky you ll bust both knees before you hit the ground If you think this can

    Original URL path: http://www.sudibe.de/articles/tchain.html (2016-02-09)
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  • SuDiBe Tandemseiten - Literatur
    enthusiastically recommend a 4 yr old Fisher or Burley with upgraded wheels and derailleurs These upgraded tandems sell for 600 800 and are often more reliable than a new tandem at twice the price Another good option is a used custom tandem Lots of guys will drop 2 000 to 5 000 on a high zoot tandem from a regional framebuilder and then discover their girlfriend won t ride with them If you spend a few months looking you might find a nearly unridden weirdly spec d tandem with flashy p aint for as little as 40 cents on the original dollar Things to watch out for are too light wheels and squirrelly single bike geometries Used Treks Trek didn t start delivering tandems until 1993 and because sales were only a small fraction of what was projected these tandems hit the factory close out list a few months later and have remained there ever since Hundreds of T 200 s originally priced at 2500 3000 were sold to d ealers for less than half price I ve seen brand new ones unloaded for as little as 1200 The T 100 originally pegged at 1800 is now commonly discounted to just under 1000 All Trek tandems even the now discontinued T 50 share an identical frame Except for chronic wheel problems Trek w ill replace the originals with upgraded wheels if they don t make it through the first year these have been reliable tandems Because sub 1000 pricing on new Trek tandems has killed the resale value of used ones a used Trek tandem can be purchased for as little as 600 700 It will be intere sting to see if prices for used Treks rebound when Trek finally exhausts the stockpile of tandem frames they produced a few years ago Used Cannondales Introduced in 1988 700c Cannondale tandems were sold as framesets only through 1992 Like custom tandems many of these early Dales will have a strange mix of components that could be very good or bad Since 1993 prices on new 700c Cannondales have remained stable while the value of the included components has dropped Prices for a 700c Cannondale with a 3 8 years of hard use will range from 1400 2000 Used Santana tandems After two years of testing the first production Santana tandems were delivered to customers in 1978 At 1200 the original Santana was not only four times more expensive than the 299 Gitane we lost money on every one By 1983 the final year we produced the marathon frame design the price of Santana s only model had doubled All of these pre model name Classic Santana tandems were built with seamless double butted tubing still exotic by today s standards These first generation Santanas sell used for 1000 1500 Mid 80s fillet brazed direct lateral Sovereigns and Arrivas sell used for 1500 2200 Late 80s Elans and Visas along with tig welded Arrivas now sell used for about what they cost

    Original URL path: http://www.sudibe.de/articles/cheap.html (2016-02-09)
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  • SuDiBe Tandemseiten - Literatur
    NivaCrom tubing is twice as expensive as butted Cromoly which makes a NivaCrom tandem 600 more expensive than a double butted cr omoly tandem and 1000 more expensive than plain gauge tandems While we think NivaCrom is worth the expense in seven years no magazine has yet agreed to even test one After NivaCrom spoiled us we shopped around for something nearly as good as NivaCrom but less expensive The winning proposal came from Tange a SuperSize version of their best seamless cromoly drawn to 8 5 8 Tange s SuperSize 8 5 8 tubing became available on the 1993 Arriva the same year the Sovereign switched to aluminum A SuperSize 8 5 8 tubeset produces a lighter stiffer stronger and more comfortable frame than oversize 9 6 9 experienced tandem riders will have no trouble feeling the difference Because thin tubing requires additional drawing operations an 8 5 8 tube is considerably more expensive than a 9 6 9 tube and possibly thrice as expensive as the typical 10 7 10 tube found in production single bikes Any butted tubeset is more expensive than the 11 11 11 plain gauge aircraft tubing used by a majority of custom tandem builders If Santana has used Tange Prestige tubesets since 1993 why doesn t Santana use the word Prestige in its catalogs or advertising The tubing Santana obtains from Tange is a special version that bypasses the final heat treatment process While heat treating improves the strength somewhat it als o decreases a frame s long term durability by making the tubing brittle which is why the tubing is heat treated after being drawn and butted Since we expect our tandem frames to be used for dozens of years Santana will not build frames from heat treated steel Even though our tubeset is the identical alloy drawn to the same 8 5 8 gauge a Prestige label would be confusing When the 1993 Arriva proved nearly as impressive as the Noventa we followed up by giving the Visa a SuperSize 8 5 8 tubeset in 1994 albeit with slightly smaller chainstays downtube and bottom tube The other development for 1994 was the world s first double butted and ovalized cromoly bottom tubes which saved another half pound Current versions of both of these steel frames are now lighter than a same sized aluminum Cannondale For 1997 the Arriva gets a larger still bottom tube and a very exotic double butted AND externally tapered downtube a giant version of Ben Serotta s Colorado Concept downtube All of Santana s tubesets are seamless Your 94 Trek tandem has oversize 10 7 10 True Temper tubing True Temper does not offer seamless steel Are all double butted tubes the same No The difficult part of manufacturing double butted tubing is producing the matching pair of steep internal tapers While a 10 9 10 tube for instance would meet the accepted definition of double butted i e it is thicker at both ends it would

    Original URL path: http://www.sudibe.de/articles/materials.html (2016-02-09)
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  • SuDiBe Tandemseiten - Literatur
    will confirm our testing revealed undeniable differences in comfort and performance We continue to test frames here at Santana Our own frames AND frames built by others When we state for instance that aluminum tandem frames built by others have a lower stiffness to weight ratio than a cromoly Santana it is because we ve purchased complete new tandems removed the components and scientifically tested the bare frames To this day I do not believe anyone else magazine or builder has performed these sorts of tests Part 2 A scientific way to compare tandems In Santana s most extensive scientific tandem testing published in 1993 we ranked the stiffness to weight ratio of every major brand of tandem then being sold in the U S The surprising answers some tandem frames were twice as efficient as others the range of efficiency among competing single bike frames is probably one fourth as dramatic high priced tandem frames sometimes scored worse than a budget frame from the same builder and double butted cromoly frames had significantly higher stiffness to weight scores than plain gauge aluminum frames Because we knew our published findings would be challenged we saved the frames and invited retesting More revealing than lab tests are comparative road tests While all of us have learned to prefer objective facts over subjective opinions it is not yet possible to objectively measure such essential frame qualities as stability handling ergonomics or comfort with an instrumented test jig And because only an idiot would prefer stiffness or lightness which can be measured over stability which can only be judged subjective road tests are still the best way to determine overall frame performance Santana has developed a methodology to verify the accuracy of subjective scoring with subsequent lab tests For instance after a panel of testers develops seat of the pants scores for stability handling comfort and stiffness we remove the components and objectively test the stiffness of those same frames And YES we have established a conscientious panel of test riders CAN accurately determine tandem frame stiffness When objective lab results verify the accuracy of certain subjective scores such as stiffness the panel s scores for unverifiable results such as stability merit a high degree of credibility Unfortunately the aforementioned seat of the pants scoring is too often unduly affected by the shape of the saddle To accurately compare various tandem frames through subjective testing it is absolutely essential to equip the frames the identical seats tires inflation pressures pedals bars and tape Because magazines usually skip this step their reports have a diminished degree of validity It is also necessary to use comparably sized frames In a recent issue of TANDEM various teams evaluated a Santana against another brand Only one captain preferred the other bike Because I was curious as to why this one captain panned the Santana I reached him by phone His answer I just couldn t get comfortable When I pressed further I learned the dissenting team s

    Original URL path: http://www.sudibe.de/articles/billonframetesting.html (2016-02-09)
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  • SuDiBe Tandemseiten - Literatur
    customers demanded 6 speed freewheels we had Phil assemble the same flanges onto his narrower 50mm barrel While the resulting wheel was still 140mm and dishless the narrower flange to flange spacing reduced the spoke bracing angle and wheel problems increased When 7 cogs became available a few years later we co designed a series of Japanese tandem hubs with only 2mm of dish While 1 10th of an inch of offset may not seem like much the resulting wheel was over 10 weaker By the early 90s customers wanted 8 cogs We did some testing and discovered a 140mm wheel with eight cogs would never meet our standards for reliability To provide 8 cogs instead of 7 without affecting reliability it would have been necessary to add 5mm to each side of the hub After considering 150mm we instead decided on 160mm to allow 8 cogs AND to recapture the strength we had lost through the two earlier revisions For the past four years all of Santana s premium tandems have featured 160mm spacing Santana did not expect everyone to immediately jump on our 160mm bandwagon After all for a decade after Santana introduced the 140mm standard most builders stubbornly continued to build tandems with 120mm and 126mm spacing I can safely predict another decade will pass before some of our competitors figure out 160mm spacing In the meantime after both Trek and Burley discovered the failure rate of 8 cogs in 140 spacing was way too high they convinced Shimano to stretch an existing and inexpensive 135mm ATB hub by 10mm to 145mm Since Shimano is the bike industry s standard maker other tandem builders quickly signed on What s wrong with 8sp 145mm Because the resulting wheel is considerably weaker than 7sp 140mm this new standard is a giant step backwards Is there a way to predict wheel strength Sure we developed a reliable wheel strength index here at Santana a few years ago First to determine the wheel s bracing angle measure the distance from the right flange to the centerline of the rim and frame The best hubs from Phil and Edco have 30mm for right side bracing An average 6 7 speed hub has about 25mm and the worst 8sp hubs have only 20mm Second determine the dish or offset between the centerline of the rim and the centerline between the hub flanges If the dish is zero all spokes share the same load The best hubs from Phil and Edco are totally dishless Suzue and Sansin 140mm 7sp tandem hubs have about 2mm dish Most hubs found on tandems have 4 5mm of dish and the very worst hubs for a tandem Dura Ace 8sp have over 7mm of dish Santana s index multiplies the right side bracing distance times degree of dish to determine an approximation of a wheel s relative reliability HUBS USED BY SANTANA Phil Wood 5sp fwl 140 Santana O E 1976 79 100 Phil Wood 6sp fwl 140

    Original URL path: http://www.sudibe.de/articles/wheandhub.html (2016-02-09)
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