Cruzbike Quest Hi Racer

 

New version of Quest with 500mm chainstay and aero, load carrying seat and tailbox.

Quest with 290mm chainstay and original seat

Quest with 360mm chainstay and 16" rear wheel and aero, load carrying seat and tailbox.

Scoping - rear suspension removal

Scoping - this folding bike frame has a very cheap version of the suspension pivot in Cruzbike Quests

Trying an MTB rear swingarm in the Cruzbike. It was slightly too wide. The visible parts of the suspension bushing were later removed.

Trying the folding bike swingarm

New 500mm fork weight is 850g in steel.

And the old 360mm fork is 330g

Similar difference in pivot hardware weight: 45g aluminium from Cruzbike

versus 110g steel from MTB

Final assembly with accidental fisheye effect

Preparing for final assembly

Widening the slots at the bottom of the chainstay from 6mm to about 10 mm was done by wearing away the steel using drills, and stepping up the drill size by 0.5mm each time. Before this slotting was done, a steel sleeve was brazed over the chainstay end to thicken it and ensure there was enough material.

Lower part of chainstay done

To reduce the width at the bearing, the lip on the outside of the bushing was removed allowing it to be pressed further into the housing. Loctite secures it in place

New top part of chainstay and old chainstay

Initial measure up. With a 500mm chainstay, the bottom bracket would be in about the right position.

Hi

 

The above photos show some of the work I've put in over the last few weeks, adapting a rear suspension system from an old, heavy mountain bike to become a long chainstay for a Cruzbike Quest. The result is shown in the top photo, it's sort-of a Cruzbike Quest Hi-Racer.

I have 2 Quests, both of which I tinker with extensively. I've already made 2 load carrying seat / tailbox sets for them, and have fitted hub dynamo lighting to one of them.  They are nice bikes, and the moving bottom bracket front wheel drive system is interesting. But for me, one of the chainstays (see pic 2) was way too short, so I've made steps to change that, looking out for, and eventually finding bike bits compatible with the Cruzbike chainstay. I bought the bits home from the Wecycle shed several months ago, and now we have some action on the building,  woohoo! During construction I used the bike as a jig. By removing the existing chainstay and moving the top tube up, I was able to place all the components together before "tack-brazing" them together. Then the chainstay came off the bike and brazing together was completed before painting.

Will report later on how it rides after a few tweeks.

For now I have been around the block and noted the following.

If, in your excitement, you forget to put your taillight on for your twilight blockie on your newly modified bike, you are a doofus. I am that doofus.

And possibly more relevant, the handlebar is too low and my legs bump into it. Moving brakes, reflector and bell would help but really the whole handlebar needs to be shuffled out of the way somewhere. 

From all my handlebar stems, I sorted out potential options for improving the handlebar position, and they are at left.

Settled on this one particular stem for now but might try others

With me on it. I'm reasonably horizontal but still comfortable. Compare with pic 2. Also note the rear suspension is compressed!  I think these sort of photos are the only simple way of assessing the suspension. The tail fairing is a bit low at the top and should be level with my shoulders.

 

Another Mixte

New front derailleur is at the back. The other one had been rubbing on the chain for a long time and is almost warn through. Both are ....

the Suntour Spirt "normally in high gear" type as described here in Frank Berto's book The Dancing Chain

Chain before replacement.

Completed bike

Milk crate = Preston Pannier mounted on custom adapter. There are 2 3d printed crate locaters, files for printing them are available on Thingiverse here.

Also 3d printed are plastic bushes for the Suntour thumbshifters.

Reflector came from the donor bike.

Chain after fixing

Original brochure from 83 / 84 Repco Catalog

This bolts to the underside of the rack to keep everything in place

Twin Thumbshifters

Donor bike

This bike (Repco 83/ 84 mixte) was listed for sale on Facebook marketplace for $20.00, and was about 1km away from where I live. So I was able to ride to pick it up, and wheel it home, riding one bike and wheeling the other. 

I was quite pleased to find it had interesting Suntour gears on it, and despite some plastic bits broken, I was able to fix them. It now rides quite well. I didn't touch the brakes: all the fixing was in the drivetrain, and I regreased the bottom bracket and used the donor bike chain. Very pleased with how it turned out and I like the sombre dark purple colour.

Fixing a Mixte

 

Mixte as traded

Huashen folding bike as traded

Mixte at home with home-painted handlebars and stem.

Initial weigh in with steel brakes, brake levers, front mudguard, cotter pin cranks and steel 27" wheels, 15.28kg

To accommodate more bikes I disposed of these ones - mixte bottom bracket is from the pink bike, and rack is from the teal bike.

Hi

Bicycles are poetry! Bikes are quite small thing compared to other transporters of goods and people (ships, cars, submarines, trams, trains), and don't even have their own motors, but they can accomplish much. If a car is a novel, then a bike is a poem, it often does the same thing, but just in an abbreviated form. Please excuse the philosophy, but my design blog post has similar themes and got me thinking about all this!

But you know, if you are surrounded by bikes all the time, the fact that they might be poetry wears off, and you just deal with them as highly repairable, highly malleable, enjoyable objects. But every now and then, a nice bike comes along and reminds you of the poetry, which is why I still muck around with them I guess.  I consider Mixtes a great design and have enjoyed resuscitating this one. I like the position of the rear brake in some mixtes. They are just in a direct pull line along the top tubes so there's a bit less fuss there compared to other bikes. Here is a link to another Mixte from a Hobart public bike shed.

A few weeks ago, a friend texted me with a "dead bike alert" including the top 2 pics as follows:  

"Bikes in hard rubbish halfway up my streer" . I'm pretty sure she meant street! Anyway, despite the fact that my house often looks like a hell for bicycles that have misbehaved - with bikes left languishing and half disassembled - I took up her tip and put the bikes in the back of my small Kia on the way to visit my Dad.

The bikes were an old mixte which I thought I could fix up, and a white folding bike. I have been eying off this style of folding bike (on Facebook Marketplace) for a while because it has rear suspension a lot like my Cruzbike Quest, and I thought they could be mined for parts. More on that later...

When I got the bikes home, I weighed and photographed the mixte. It had been partly spray painted grey and looked a bit manky.

Scavenged parts fitted were alu centre - pull brakes, cassette bottom bracket with square taper shaft, alu crankset, steel handlebars, shifters, Alu brake levers, alu 700C wheels, rack and rack adapter for milk crate,

The "after" photos follow, I'm happy with the result but I haven't ridden it yet. Still on the to do list are 

Attach rear reflector

Fit bell

Reattach rear derailleur  by drilling and tapping into frame. This is to move the back wheel further back to fit in with the size of rear brake I've fitted.

 

 

 

New brake position is under top tubes to avoid damage to brake cables when mounting the bike. (Practical but sightly less pretty and poetic) Also, wooden rack adapter is shown

Crate mounting detail.

Bike with crate attached

Woohoo, I have bling! A full set of brake and gear cable outers was gleaned from the white folder.

Just about finished

With rack and crate adapter, the bike weighs just a bit more than the original

 

Racing bike refit

 

Almost there, with new seat.

Some more detail of the

new gearing setup with orange 3d printed cable guide.

The first seat I put on was pretty manky.

Last Saturday during my volunteer work at Wecycle, a gentleman came and donated a small framed racing bike in good condition. The shed was quite full and an executive decision was made to recycle this bike for parts. After the brakes, handlebars, quill stem, seat post, seat and wheels had been removed, I jumped in and asked if I could take the rest home as the frame looked quite good.

As the bike came to me without handlebars, I felt free to change it however I liked, and chose bars from a town bike. These are completely different to race bars with the hand grips at least 20cm above the racing bike drop position. But unlike the racing bike bars which prioritize speed, with these bars the bike could actually be quite comfortable to ride. Along with the wider handlebars came a better brake position, and also the need for a better gear position. There are some bolt on kits available for adapting downtube shifters to shifters on handlebars, and a local shop is selling them for a good price.  

But I realised that adapters weren't necessary, as a gear cable outer can easily start at the top of the existing shift lever. I only modified the right hand shifting mech, as this control is for the rear derailleur, which is activated far more often than the front derailleur. So suffer slightly if you have to change gears at the front with the left hand control!

There's not much of the new gear change cable sticking into the downtube shifter, so to secure it I designed and 3d printed a cable guide which fits neatly into the lugged frame. The cable guide and cable outer are lashed to the frame with cable ties. Although a few cable ties on their own would have done the job, I think this looks a bit more elegant and says "don't touch!".

The bike's finished now, it rides quite nicely, and on Saturday I'll see if it gets the thumbs up from my fellow volunteers. 

Regards Steve Nurse

Rad bike centre and cycling in Christchurch

 

Flyer and Sticker

Nearby bike sculpture

Koha can be roughly translated as "consideration". Its not a payment or a price, more a tribute for services rendered.

Lots of donated bikes, there's an old Raleigh 20" in there somewhere.

It was lively...

all afternoon, with a wating room complete with bike books and toys for people waiting for bike service, repairs or access to parts.

From the front: roadwork is in anticipation of the Te Kaha stadium due to be opened in April 2026

I mostly fixed this one! Removed and replaced a broken ferrule in the shifter and shortened the chain by 2 links. Not sure the 9 speed shifter was compatible with the 8 speed cluster though!

How it works!

All the bits.

Stadium within a stone's throw.

Temporary cathedral and stadium

Latimer Square

Home of Buycycles is nearby

Hi

 My girlfriend and I have just come back from New Zealand, and while there, I was in touch with some recumbent enthusiasts, and also volunteered at RAD (Recycle a Dunger), a community bike workshop in Central Christchurch.

RAD  were very accepting of me as a volunteer (I'm experienced and have had paid work in not-for-profit bike servicing and restoration), and in about 2 1/2 hours I had progressed from stripping bikes for parts to fixing a mostly-finished town bike with a single front chainring. Most of Christchurch is very flat and a single speed bike would do the job in most cases - I think load carrying would be more of a priority than heaps of gears.

Old parts were kept from bikes that were stripped, and this was important. Many of the bikes that came in had mismatched brake and gear levers but this wasn't seen as a problem.

Thanks to RAD! Was very glad to pootle into town and meet like minded folk.

Regards

 

Steve Nurse