Cruzbike Sigma Repair

Ready to go

Update Aug 28, 2026: now listed on ebay for a 1 week auction, pickup from Melbourne, Australia, with start price under $50  here is the link, https://www.ebay.com.au/itm/147522029712  regards
 

My friend George passed away over a year ago, and he left a considerable number of bikes for his wife Christine to deal with. I've already passed on 3 of his Linear recumbent bikes with 2 of them raising money for OzHPV. I recently received another 4! At the moment I'm tackling the Cruzbike Sigma.  

This is not a typical Cruzbike. It is a brand that originated with John Tolhurst from Perth, Western Australia with the sale of a conversion kit to make a front wheel drive recumbent from a Y-Frame mountainbike. Now, under Jim and Maria Parker (USA), Cruzbike is a leading recumbent manufacturer, still making front wheel drive bikes. They only made one rear wheel drive bike and this is it.

Firstly to describe the bike I'm repairing and its problems: 

The back tyre was flat and that's fixed now.  A guide to the SRAM Imotion 9 gearbox in the rear hub showed me how to unhook and rehook the gear cable to remove the back wheel.

Seat base as drill template for Merbau timber.

 

The top part of the seat was cracked - the seat is one of the only parts the Sigma has in common with other Cruzbikes and this problem is relatively common - see here !  My fix was to make a replacement top seat part from Merbau  and strong plywood timber. I used the lower part of the seat as a drilling template and have done my best to alleviate stresses using rubber strips as suspension and metal plates to distribute load. I had some velcro strip, and the last step was to glue that to the timber to make the seat pad stick.

 

The rack and rear mudguard was supported by cable ties fastened to the seat struts. This made seat adjustment difficult. The mudguard mounting points were changed, it was cable tied to the rack, and the rack is now supported by a strut which bolts on to the frame. Quite proud of that and it looks good, and the seat can be adjusted easily now..

 I 3d printed 2 bar stoppers for the bike so the mirror that comes with the bike can be fitted either side. As well the drilled light bracket at the front has an adapter converting it to 22mm handlebar size, and a Cygolite rechargeable light is included. Rear  / functioning battery taillight / reflector and bell also installed, and the bike's original wireless speedo is supplied loose with batteries already fitted.

 

So here is the rebirthed bike out on its maiden voyage. Everything worked well but the steering takes a bit of getting used to (after about 3k on it I found it easy to ride). I haven't done all the work I can on it (for example 2 cables should run through the large lower frame tube but they don't) but I'm satisfied with what I've done.

There are some remarks about the handling in the  Cruzbike Sigma Forum Page here, and an earlier post here describes John Tolhurst's design intentions for the bike.

 

I was intrigued by the lettering and designs on the Sigma, and one sticker says designed by John Tolhurst and Ron Witt.  I googled Ron and soon found this page, which describes Ron's strong desire for a recumbent bike that started after a bike accident when he was 16. The page also describes the Flash Recumbents which came from the Perth suburb of Midland and were made from about 1982 to 1992. (I had heard of Logo Trikes from Western Australia, but not Flash!) One of the Flash bikes shown in the picture has large wheels and remote steering in the centre of the frame, a bit like the Wilson Bikes made in Melbourne.

Finally, a recent Facebook post from Glen in WA indicates there are about 3 Sigma Cruzbikes regularly on the road in Perth,  and a few extra ones lurking in garages.

I plan to sell this bike on ebay and will get the  auction going in a week or so with proceeds going to OzHPV.

Regards Steve Nurse 

 

 

British Human Power Club Racing

Picture by SN

 Hi

This post follows directly on from my last one - even though it all took place a year ago, this story hasn't been published on my blog, instead it went to the OzHPV magazine Huff. But there are some good pictures here so I think that they should see more daylight. Or whatever the right word for computer exposure is. I'll stop rabbiting on now!

From Huff: "For a while I had been planning a trip overseas and wanted to attend the World Human Powered Vehicle Championships. This year they were in northern Italy and I was considering at least visiting if not competing. However health issues got in the way and the time was too tight to visit the championships by the time I could book to go. However I see all the British Human Power Club news on Facebook, and looked up their events. There was one in Hull which fitted in well with my schedule. I was already visiting the Netherlands and I found it was possible to travel from Rotterdam to Hull by overnight ferry, and I took that option.

Riding to Ennerdale (Pic SN)

 

 

Racing at Ennerdale (Pic JW)

 

 

The BHPC races were at the Ennerdale Sports Centre on the northern edge of Hull, and my now – handlebar mounted smartphone got me there without any problems. I’d worked out how to carry a backpack on the bike and had some food provisions so was well set up for the Saturday of the 2 day race meeting. On arrival a crew of recumbent riders had assembled, mainly with station wagons or vans with bikes, trikes, velomobiles and streamliner bikes squeezed inside. There's quite a family feel about the races and some teams were generational with one dad and his sons in shark-themed streamliner bikes and another father-daughter group racing a Russell Bridge streamliner. One rider had a fast low racer by the late Mike Burrows with a fastidiously restored and repaired tailbox. He said that this was the last relatively simple streamliner Mike had made - later ones had more complicated indirect steering. There was a vintage Greenspeed GLR there as well. At first I thought it was home made but it had just been widened by its owner to accommodate him. 

 

Greenspeed GLR a long way from home (Pic SN)

Judith Swallow – very gutsy (Pic JW)

 Actual racing was two 45 minute road races and a 1.1 kilometer time trial. It rained a lot during the day and the only shelter was under tailgates, umbrellas and in vans and trailers. I was the only one who had arrived by bike and at the end of the day needed to shower, dry off, and dry all my clothes. 

Dave and his..... (Pic JW)

 

 very fine upright trike (Pic SN)

Streamliner racing (Pic JW)

 

Streamliner racing (Pic SN)

 

Sunday saw a fresh batch of riders including Russell Bridge and Barney Hale who have both been on the American Laidback Bike Report series. Russell makes streamliners from scratch, and like Mike Burrows before him has moved his bikes on to other BHPC riders. He names his bikes after Charles Schulz peanuts series and has models including Snoopy and Woodstock. Sunday's races consisted of a 90-minute rice followed by a time trial. The weather was threatening again and I didn't push it hard in the road race, taking a break of 40 minutes in the middle. This was in contrast to Steve (Slash!) Sleigh, who at 60 won all the distance races of the weekend. His friendly rivals for speed include Russell Bridge who finished just behind him in the 90 minute race. Also racing were Judith Swallow and her partner Dave who is from Brisbane. Judith is an Audax legend and rides, races and Audaxs on upright and recumbent trikes – disability has forced her off bikes but she is extremely gutsy and continues to ride. For this meet, Judith rode a recumbent trike and Dave a very nice, suitcase packable upright trike. I also sheltered in their van for a while! 

Streamliner racing

 

Barney Hale with corflute mudguard next to a Windcheetah

 

One of the spectators took a few photos of me going around on my camera. I took photos too, and also chatted to the main camera person for the day, Jack Watson. Later Russell Bridge and Barney Hale set up and ran Russell’s camera speedbike over the longest straight of the course. Alas, I lingered and chatted for too long at Ennerdale, and copped rain on the way back to the hostel. Once again I was thoroughly soaked. I was quite relieved to pack the bike up at the end of the day and leave Hull the next morning for a home away from home, my brother’s place in Folkestone.

Steve Sleigh’s Beano is tiny and has a complex looking drive setup 

 

.......... but it can really go (Pics SN)

 

Burrows Ratracer Cadillac

 

Steve Sleigh and Russell Bridge feature in the Global Cycling network video about fast bikes at https://www.youtube.com/watch?v=tW1bjsOuk8s and at the time of writing are in Battle Mountain for the World Human Powered Speed Challenge. They are way faster than me and rock stars of the HPV world. Thanks to Jack Watson for permission to use his photos and to BHPC for organising the Ennerdale Weekend. The next WHPVA world championships will be held in Holland – very close for the English HPV mob, and many were planning to attend, see https://www.facebook.com/groups/433368653698615/ ."

Postscript: The Holland WHPVA championships have now been and gone and I still didn't make it to them. Maybe next year. There is a much richer all-comers recumbent cycling scene in the UK compared to Australia with multiple meets at various tracks throughout the warmer months. In Australia we struggle to organize one meet, but I am trying and have been organizing an open design cycling event for Coleraine in Western Victoria from October 31 to November 2. If you've followed my Instagram you'd know its open for business!

Here are the the important links: 

Facebook full Event Description

Enrol!

Prizes and Giveaways 

Regards Steve Nurse