GREENSPEEDER

Greenspeed's bi-monthly newsletter
No. 2 November - December 2003


View from "Five Ways" on the road up Mt Dandenong, near Ferntree Gully.

 

During the last two months we have been busy with shows in both Australia and the USA. These shows require quite a lot of preparation, as well as time away from the office and the factory. However they give us the opportunity of meeting face to face with dealers and customers, and enable us to gather valuable feedback on our trikes and our service. Also coming up this month is the annual Maryborough Pedal Prix where over 150 school teams compete in a 24 hr race, scoring points for construction, design, and presentation, as well as race results. So this is a busy time of the year for us, as we head towards Christmas and our summer holidays. We will be taking two weeks off over Christmas, knocking off on Friday the 19th December, and resuming on Monday 6th January 2004. 

                                                                               Ian Sims, November 2003

Contents:-

    1. New Headrests
    2. New Tandem Stoker Handle Bars
    3. GS Options  - The Rohloff 
    4. GS Options - The Schlumpf
    5. Christmas deliveries 
1. New Headrests

The main feature of any recumbent is the reclined seating position. This position both reduces the wind resistance, making the machine more efficient than an upright bike, and also makes it more comfortable, as there is less weight on your backside. In fact the more reclined the seat, the faster the machine. This why our Touring Trikes have a 40 degree seat, whereas our Race Trikes have a 20 degree seat.

However a few riders have found that even with a 40 degree seat they seem to be holding their heads forward, and they find this uncomfortable. Usually this disappears after a couple of hundred miles, as the neck muscles adjust. If after a couple of months it is still a problem, then we now have a new headrest. Unlike the old head rests, which were just an extension of the seat, with a small sub-frame and extra seat material, the new head rests are adjustable both up and down, and fore and aft. Furthermore they cause less air drag than the old headrests, and fit both the standard seats and the wide seats.

As the headrest interferes with flag posts in the existing holders, new flag holders are provided on the new headrests.

The adjustment is made possible by using a wedge in the seat tube similar to bike handle bar stem. So the side arms can be moved up or down, and swivelled fore or aft to adjust the position of the foam roll. "O" rings are used to seal against the entry of water into the seat tubes. Two "O" ring grooves are provided. The upper one is for the standard 0.035" wall seat tubes, and the lower, deeper, one for the heavy duty 0.049" seat tubes, which are a little smaller on the inside diameter. A small amount of grease will help the "O" rings to slide in the top of the seat tubes. The foam roll is designed to fit the nape of your neck, so that it does not interfere with the wearing of a helmet. Price of the headrest in Oz is $120 AUD. Please contact your local GS dealer or email Rachael to order.

 


Touring Trike



Race Trike

 


Headrest on Trike

 


Headrest on Seat

 

 


Headrest Side Arm

 

 

2. New Tandem Stoker Handle Bars

It is a fact, that in general, women have longer legs and shorter arms for their height than men. Thus a number of women have found that the stoker bars on our Tandem Trike too far away to reach comfortably, when the bars were on the end of the seat tubes. Thus we have now redesigned the stoker bars so that they are attached underneath the seat, to a new fitting on the main tube of the frame. The "bar ends" are the same ones as used on the new GTO handle bars, and are adjustable for both width and rake, which also provides a measure of fore and aft adjustment. They were introduced last month, after months of research, and are being fitted to all new tandems.

See pictures for details note width marking on the bar ends (cms).

 


GTT Tandem Trike


New Stoker Bars


Adjustment Marks

 3. GS Options The Rohloff.

I get a lot of questions from new customers about options, so I shall give you some of the history behind them, and attempt to explain the advantages of choosing various GS options.

Barbara and Burnie Rohloff liked to ride their bikes along the beach, but found that the sand clogged the derailleurs and stopped them from working. So they had a dream about making a transmission which could be ridden along the beach without any problems. By putting all the gears and the shifting mech. inside the rear hub, this dream was achieved in the shape of the 14 speed Rohloff Speedhub.

IMO this hub is a huge leap forward, over all the bike gear systems on the market. Why?

1. Lower maintenance.
Unlike the derailleur gears which work by derailing the chain from one cog to another, and are exposed to dirt, water, and accidental damage, the Rohloff internal gears run in a sealed oil bath, much like a car gearbox, plus the indexing system is inside the hub, rather than in the shifter. Thus there is no need for regular gear adjustment, and derailleur replacement. The oil needs changing only once a year, or every 5,000 kms.

2. Easier gear changing.
With a 27 speed mountain bike you have TWO levers or twist grips. One for the triple crankset, and one for the 9 speed rear cluster, and many ratios overlap others, plus some combinations are not advisable, due to chain misalignment. Furthermore there are uneven jumps between the gears, so it is not easy to always select the right gear. Whereas with the Rohloff, you have one shifter which goes all the way from 1 to 14, covering the same range, with even, slightly smaller jumps, making it much easier to select the right gear. PLUS you can change ALL the gears when stationary, as well as in motion. Thus if you've forgotten, or not had time to change down after a sudden stop, you can easily select the right gear before taking off.

3. Range.
In a single hub, you have the same range as achieved by a 27 speed mountain bike set up with a 9 speed cluster and a triple chain ring. Or a SRAM 3x 9 DualDrive hub. However with the Rohloff you can change your whole gear range up or down, by just changing one rear cog, rather than a whole cassette, which is more limited in the sizes available. The Rohloff cogs are available in 13, 15, 16 and 17 teeth. The internal ratios are :- 0.279, 0.316, 0.360, 0.409, 0.464, 0.528, 0.600, 0.682, 0.774, 0.881, 1.000, 1.135, 1.292, 1.467.

4. Efficiency.
The Rohloff hub breaks the mould for geared hubs. While other geared hubs use only plain bearings in the pinions, and are greased once at the factory for life, the pinions of the Rohloff run on roller bearings, and in an oil bath, giving efficiencies comparable with derailleur systems. Plus better chain
alignment further increases efficiency while reducing chain wear.

5. Strength.
With a seat back behind you, it is possible to put more force on the pedals of a recumbent than an ordinary bike, plus with a recumbent trike you can gear lower than a bike, as there is no falling off when the speed is too low. Thus some people have managed to break some of the other geared hubs, and we have broken the Shimano LX hub in testing. Whereas none of our customers have even managed to break the safety shear pins in the Rohloff. In fact I witnessed the hub being tested and approved for TANDEM use at the Rohloff factory. Plus the bearings in the hub are larger than used in other hubs. So whereas some customers have worn out the bearings on the SRAM hubs by overloading their tandem trikes on long tours, I would not expect this problem with the Rohloff.

Disadvantages.
Main disadvantage is the cost, with the Rohloff option being a $1,350 AUD ($945 US) upgrade. As the twist shifter is
designed for ordinary bikes, it does not work quite as well as the Shimano bar end shifter, but this can be alleviated by dropping the hand down on the handle so that the thumb and fore finger engage the twist grip. Experiments with full length prototype twist grip shifters have not shown a lot of improvement, as has inverting the twist grip. The Rohloff factory is currently working on an electric shift and an automatic version. The only other disadvantage we have found is that they are generally noisier than the derailleur gears, esp. in the lower 7 gears, when two gear trains are in operation in the hub.

 

GS/Rohloff changes
In fact we have been so impressed by the Rohloff that we have had special Rohloff dropouts made for our trikes, so that should people wish to retro fit these hubs to our trikes, this can be done without needing the large after market torque arm. The LH dropout has extended fingers to engage torque stop on the Rohloff OEM axle plate. Plus we are fitting both the cables stops needed for the SRAM DualDrive, and those needed for the Rohloff. In addition we have changed over to fitting the External Cable Box, originally made for the disc brake version. While this is more expensive than the basic hub with the bayonet cable fittings, it avoids the special fine, small cable inside the hub, makes it easier to the remove the rear wheel, and gives easier cable adjustment.

 

 

 


Rohloff Poster
2353 x 3122

 

 


Inside the Rohloff Speedhub 

 

 


14 speed shifter

 

 

 


Derailleur Comparison

 

 

 

 
Alternative Cogs

 

 

 


Rohloff in Tandem

 

 


Rohloff Shifter on Trike Handle Bar

 

 

 


Rohloff Dropouts


Rohloff External Cable Box


Cable box removed

4. GS Options - The Schlumpf.
Florian Schlumpf designed his Mountain-Drive, so that people with an ordinary 3 speed bike would be able to climb the mountains in his native Switzerland. Thus with this 2 speed bottom bracket, the two gears are wide enough to give six speeds with a 3 speed hub, WITHOUT any overlap. Thus while top gear is direct, low gear is only 1 : 0.4. That is for every revolution of the chainring, the cranks revolve two and a half times! Thus if one has say a 60 tooth chain ring, going down to low is like using a 24 tooth ring. This is a much wider range than you would get with say a touring triple crankset, where the rings are normally 52/42/30. The gear change is
executed by kicking a button in the centre of the cranks, dispensing with cables and shifters. This can be done with the heel without taking the foot from the pedal, or without disengaging clipless pedals. Hit the right button for low gear, and left button for top gear. For people with short feet, we have Easy Shift levers attach to the crank arms, and extend over the buttons.

There are two other versions of the Schlumpf, known as the Speed-Drive, and the High Speed Drive. The Speed- Drive has a bottom gear of 1 : 1, and a top gear of 1 : 1.65. So this is useful for cycles with small wheels, giving an overdrive of 65%, and avoiding oversize chainrings. The High Speed Drive has a 1 : 1 bottom gear, and higher 1 : 2.5 top gear, and is useful for small wheeled cycles needing a wider gear range.

Which Schlumpf to use?
People usually choose the mountain-drive to extend their gear range beyond the standard range offered by the standard DualDrive and triple set up, which normally gives a gear range from 13 to 125 inches. The standard 60 t ring
will expand the range from 11 inches to 145 inches, giving gears high enough for a full fairing, plus even lower hill climbing gears. For those needing lower gears for mountain climbing with a camping load, or pulling a heavy trailer, a 52 t ring is used giving a range from only 9 inches to 125. The mountain-drive is available with both 130 and 110 mm pcd spiders to take a wide range of chainrings. I have found the mountain-drive particularly useful for fully faired trikes, where use of an 80 t chainring will extend the range with the DualDrive hub from 14 to 196 inches.

Some prefer to combine a Schulmpf with the Rohloff, to eliminate all the derailleurs, and to have a cleaner looking trike without the front derailleur post. The Speed-Drive is normally used for this, as it needs a smaller chainring, has enough range for most uses, and is more efficient than the m-d in low gear. The speed drive will only accept chainrings with a 110 mm pcd.

The mountain-drive can also be used with the Rohloff, as although this is not recommended for ordinary bikes, the lower wheel loading on the trikes, plus the smaller wheel size, reduce the maximum torque loading on the rear hub. This combination has also been used successfully on our tandem trikes, where cranks are connected 90 degrees out of phase, to provide a smooth power transmission.

The High Speed Drive is a new device, which has the advantage of having roller bearings in the pinions, and should be more efficient, but is only currently available with a 27 speed chainring. This may give chain/cross member interference on some GS trike models. The 27 t ring would be equivalent to a 67 t ring in top gear. Used with the new Shimano Capreo 9/26 9 sp. cassette, and rear hub, this would give a range from 17 to 124 inches with a 16" rear wheel.

The only disadvantage we have found with the Schlumpf is that there is a small power loss in low with the m-d, and in top with the s-d. However I don't notice it on the road, and it seems a small price to pay the great range. Thus I've fitted one to the new faired trike I'm building for myself, with a Rohloff rear hub. More details in the next newsletter.

 


Mountain Drive

 

 

 

 


Speed-Drive

 

 5. Christmas deliveries.
This year, thanks to our expansion, we have managed to get a little ahead with our orders for the 1st time, and can now
guarantee one month delivery on standard size GTOs in all frame colours. Seasons greetings to all our customers and readers!

Greenspeed Recumbents
69 Mountain Gate Drive
Ferntree Gully
VIC 3156
AUSTRALIA
Phone +61 (0) 3 9758 5541
Email ian@greenspeed.com.au
Web Site www.greenspeed.com.au