News and Events

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Friday, April 21, 2023

A Cruzbike


ex-seat support (not that great)

New custom seat nuts

Drilling seat nuts before final tapping

This Quest has Y-frame mountain bike DNA, this is the right back dropout which still has a part derailleur hanger thingy.

Seat is on the floor

Seat nuts before final drilling.

Fossicking in the shed found a 27mm seatpost and a bent bit of steel which will serve as back seat supports later.


Brought the Cruzbike home using one of my load bikes and with the help of our train network. It had an electric motor and controls so was too heavy to break up and carry on the load bike.


Las week, I posted about bringing a free Cruzbike home, and have since started work on restoring it to action.  It was in fairly ordinary condition and had an electric motor fitted, and I have set about restoring the bike. I texted my friend ebike Ben, and he came and picked up all the electric bike stuff (front wheel with motor, controller, throttle, display).

The top photo shows some of what was in place as a seat support, obviously complete crap!

Anyway, mounting the seat is about 80% of the work of getting the bike on the road and I'm about halfway through fixing that.  Will report more later.

PS Years ago I made several moving bottom bracket bikes a bit like this one, mostly from a Cruzbike kit I had. When I get around to it, I will add some more links, but here is one for starters.

Regards Steve Nurse

Update May 27, 2023

Sorted through my chainrings on the way to finding a 40 tooth biopace model.

Seat support: brazed but not painted

Some good progress over the last few days. I brazed the seat support together, and cleaned up the bike removing existing front derailleur, shifters, and 9 speed cassette. I have now replaced the cassette with an 7 speed, and have a 8 speed Sunrace CSM 680 11 - 42t cassette on order. 

 Soon I plan to install a single chainring, and my quick calc for the tooth count is

N = 52* (243 / 320) which is the number of teeth on my 20" single chainring recumbent times the ratio of wheel radii between my 20" and new 26" cruzbike. So about 40. And my shed fossicking revealed a 40t Biopace chainring, so I will use that for starters. 

Getting down all the chainrings has been good, I have been able to sort them and recycle old ones I don't need including steel cotter pin models.

Regards Steve

Later on: Later I was able to fit a chain and non-indexing shifter to the bike along with the biopace (its only slightly oval and not very exciting really) chainring. I went for a ride and "conquered" an entire block without putting my foot down.

This was quite an achievement as I came off my bike less than 2 weeks ago, still have all the scars to prove it and have just got down to 1 bandage after having about 5 at the start.  So no great ambitions for riding just yet, but I will slowly tweak things so it rides better. I have ordered a disc brake back wheel for example so it has 2 functioning brakes!

Will report more later.

Update May 10

2 new parts have come in for the bike, that is a back wheel from Whites Bikes, and a 11 - 42t Sunrace 8 speed CSM680 cluster. As well I picked up a brake disk and an asymmetric chainring from a bike shed where I volunteer. For the moment the chainring and cluster are parked on the kitchen table as I deal with the (slightly!) more important issue of having adequate brakes on the bike. At the moment the disk rubs on the brake calliper so some sort of back wheel rejig is needed.   

Bike shed mission for extra parts. See also this post .

Need to sort this out, meanwhile

Some other parts are.....

parked and being

incorporated into temporary sculpture on the kitchen table. (Mary did this one and started the whole silly sculpture thing)

Update May 13

Yesterday I managed to sort out the back wheel using a nut of the right thread found in the shed, and a washer. I thinned out the right hand side lock nut and added a washer to the left hand side and then hey presto, no more disc rubbing and I was able to keep the axle protrusion the same on each side.  Then a bit of tuning, repositioning brakes etc, and the bike looked good to go.

So today I actually tested it, riding mostly on paths but occasionally on road. I almost made it up one challenging uphill gravelly section (I can't manage the "Deep Rock Hill" on my Fred Bikes because there's not much weight on the front wheel) but couldn't get into the lowest gear so failed. A mission for another day. Overall the bike is very comfortable and nice to ride, but my only luggage storage is in zipped up pockets, and that limits ride potential.

Meanwhile, the sculpture embellishments are continuing on the kitchen table. Eventually I will use the new sunrace cluster (on a bike, who'da thunk it!) and have to bong it all down but will probably replace it with something equally ridiculous.

Bits from the shed yielded a narrow wheel nut, seen on its axle in the foreground. The container at the back is a sample electric motor cowl from my time at CMG / Regal .

New parts ready to add to wheel axle.

New parts on wheel axle.

In the wild, part of a

3 or 4k off road circuit used to

test the bike. Autotimer not smart enough to focus properly.

Meanwhile the sculpture embellishment continues.

Update May 14

Today I tuned the gearing so I was able to get into the lowest gear and went for a test ride on the same circuit as yesterday. It was hard work, but I was able to conquer the Deep Rock hill this time. The cruzbike has a bit more weight on the front wheel than my Fred bikes.  Still a nice bike to ride and it was nice to get out in some late Autumn, late afternoon sunshine.

Update May 19

As I posted on facebook today, "Went out for a ride yesterday, it was about a 10k flat ride on bike paths, and a fun ride. I could overtake most regular bike riders but some of them then felt the need to overtake me back again, which they did. But on my homemade bike with aero tailbox on the same stretch its mostly no contest, I overtake and never see them again. Weight distribution is different too, I can "endo" the Cruzbike but not my homemade bikes. regards steve"

So really the restoration process of the bike is over and now I want to do some modifications and improvements but will save that for a new post.

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