Challenger Velomobile

Challenger Velomobile

Monday, 19 August 2013

Gearing with electric assist

Having tried out various electric hub motors and finally gone for the Sunstar kit meant that I was now restricted to a 48 tooth front chainring. The 9 speed 32-9 rear cassette went back on, replacing the 72 chainring and 32-14 rear cassette.
Having just about managed the steepest hills the Chilterns can through at me, top speed on the flat and downhill was still an issue. Gearing was always going to be an issue on a 20in wheel.

A great website is: as you can insert a multitude of combinations of chain rings and cassettes to compare them for you target gearing.

This allowed me to come up with a range of options to price. The Rohloff was just too expensive, eyewateringly expensive. I ended up selecting the Sturmey Archer dual drive which would allow me to install a 11-32 9 speed cassette.

Will update to record if my Strava readings improve as a result.....

Monday, 19 November 2012

The 2nd year with the Challenger

The first year with the Challenger was in fact a challenge! I started off being unfit, overweight and failed dismally in my aim of cycling 5,000 miles per year only completing about 2000 miles. The first 500 odd miles was done without electric assist and cycling anywhere in the Challenger nearly killed me especially as I live in the Chilterns Hills. 

The velomobile clocks in at around 33kg without electric assist and I did a few 40 milers but was finding that I was no more quicker than if I cycled on a conventional bicycle. Hill climbs always involved dropping down into "granny" gear and slogging away to the top of each hill and being shattered at the end of the ride. Downhills were fantastic as the Challenger just kept accelerating all the way to the bottom but I didn't manage to break the 50mph "barrier". 

I'd always intended to add electric assist to the Challenger to compensate for the disadvantage of the additional weight with the resultant poor acceleration and hill climbing ability. Selecting an electric assist motor was not a simple task. There is an ever increasing number of options being presented on ebay and the problem you find is that UK sellers want huge premiums on imported Chinese components. But wanting to buy local, I began with purchasing a "high end kit" from a UK seller offering what he described as unique having a bespoke controller. Being a fledgling industry, typically, the guy disappeared after only supplying me with half a kit and no instructions. Biting the bullet, I then went for purchasing direct from China over ebay  a new hub motor, controller and battery. On arrival, the kit was installed using the basic instructions but it meant replacing the gear shifters and chain to accommodate the cheap 5 speed rear cassette. The 1000w motor and 20ah battery added a whopping 20 kg to the velomobile so when the battery died for the first time, I soon developed a paranoia on battery status as it was nearly impossible to cycle up most surrounding hills. Also, the 14 tooth top gear only allowed pedalling up to about 20 mph with the 20in wheels. Back to ebay and a new 80 tooth chainring solved this problem. 

In the spring of 2012, Marcin from Ocean Cycle joined me for a 90 mile round trip to take the velomobiles to a schools career day at Bicester. With the electric assist giving me complete confidence, in spite of the numerous hill climbs on the way plus giving Marcin about 20 years, I would be able to keep up. 

Ready to start trip to Bicester

Not often do you see a velomobile on British roads but 2 together is always going to create a bit of a stir. This may have been the reason why the Oxfordshire rush-hour traffic gave us plenty of space and friendly gestures. By taking the country cross-country route, we certainly didn't cause any delays but even on a conventional bicycle, some drivers can get short tempered even if you only add a few seconds to their journey.

The first downhill to RAF Benson
The route to Bicester took us through RAF Benson, then through the villages of Ewelme, Stadhampton, Milton, Tiddington, Oakley and then finally to Bicester.

Velomobiles in the fog and rush-hour traffic

In the lower lying areas we hit dense fog which was a slight concern as commuters were "belting" along country lanes not expecting anything like two velomobiles in convoy. 

Typical UK disconnected cycle route; why end here?

Poorly designed cycleways in Oxford results in cyclists not using them. Definitely not good enough for velomobiles as much slower than using roads. 

Apparently, 22 cyclists were killed on Oxfordshire roads in 2011 out of a total of 122 in the entire country. This is crazy statistics considering most of the county is rural and Oxford is apparently a "cycle friendly" city. Some people blame the rising number of cyclists but cycling has also increased in cities such as Paris with its apparent crazy drivers with practically no cycle deaths. So it can only be down to poor driving, poorly designed junctions and inadequate cycle lanes? 

Cycle parking also pretty dismal in Oxford

Sunstar electric assist on ICE trike at the NEC Birmingham Bike Show

At the recent Birmingham Bike Show I came across this Sunstar Electric Assist motor which drives the crank as opposed to my existing hub motor. After calculating the potential  weight savings to be about 15kg, there was little choice but to spend out on a new motor. The 20ah battery weighing in at about 11kg was damaging the Challenger's bulkhead. I'd also noticed significant drag on the hub motor which had reduced my top speed down my favourite hills and my gearing (80 tooth front chain ring and 28-14 rear cassette)

Sunstar electric assist supplied and fitted by Electric Transport Shop in Cowley, Oxford

All the weight supported on the ICE frame instead of faring 

After replacing the original rear wheel with the 32-9 rear cassette and removing all the electrics associated with the Chinese hub motor

Challenger on exhibition at the Whitehill Bordon Ecotown open day in October 2012


Challenger outside a recently completed hemp ecohouse near Reading being the regular commute in 2012
Outside first "passivhaus" in Oxford designed by us and built by local contractor

Along the Berkshire Downs on way to Big Green Home Show

From the inside

On cycleway in Swindon returning from Big Green Home Show

Thursday, 9 February 2012


The Times Cities fit for cycling

FISSA|AZIONE: The Trike: Have a look at this velomobile...... just amazing but doubt whether it could actually be used on those cobbled Italian streets

Tuesday, 24 January 2012

Oliebollentocht 2009 - part 1 Largest meeting of velomobiles in the world

The Times Cities fit for cycling

This is why Holland is so far ahead at promoting cycling with fantastic cycleways and bikes having priority over cars. In order to get a dramatic shift in encouraging commuters away from their cars, we need cycleways like those in Groningen, Holland. AND Velomobiles to provide protection from our weather. The Challenger Velomobile would do well in Holland as offers full weather protection. Wouldn't be a bad idea for to start marketing over there? I wonder how many are sold in Holland?

Monday, 23 January 2012

Bricks and Bread by umkokolo at Garmin Connect - Details

The Times Cities fit for cycling
Bricks and Bread by umkokolo at Garmin Connect - Details

Used the Challenger for a 71 mile round trip to attend sustainability workshop at in rush hour traffic both ways. Managed to keep up with XJS Jaguar from Henley to Wokingham (9 miles) as caught up with him at every traffic lights.

Constant stop start in traffic took toll on battery as ran out of power 3 miles from venue. Return took different route and plenty of battery left. Swapped some homemade bullace jam in return for recharging battery.

Going by car might have saved 1/2 to 3/4 hr each way.......maybe???