News and Events

Keep up to date with the latest news and events of Modular Bikes.

Tuesday, July 27, 2021

Front Wheel Rework

 

Sram derailleur showing the issue I had with it. The "low" grub screw actually limits the motion of the derailleur in high speed as well.

Sram derailleur, now ...

replaced by a Shimano, and it works.

Hi

Recently the front wheel of my recumbent started groaning and whining, and rubbing on the v-brakes.  As is usual on something we use often, I ignored it until I noticed a broken spoke. And then I finally decided to fix it, and managed to fix a few other problems at the same time. Above is the derailleur issue, I could never adjust it properly, and only found out why after close examination, see above.

Below is how I fixed the spoke and below that (bit more of a general bike fix) how I refilled an oil bottle. Very happy with how the bike is going now, but I could strip and clean the wheel bearings and derailleur. After years of working as a self-taught bike builder, I attended a bike mechanic's course at back2bikes, partly as a student, and partly as a volunteer helping other students out. It was good, I enjoyed myself, learnt quite a bit and am a bit more confident with some bike fixing.

M2.5 die used to put a thread in a spoke shortened to match the other spokes in the wheel. It worked for me but may not always work. Spoke threads are usually rolled, and raise up the surface of the spoke but the tapping doesn't do this!

Bike trainer used to true wheel.


Wheel truing using an aluminium beam to..

check the side to side rim movement. Replacing the spoke, tightening some, and loosening others managed to get it quite close to true. 

Cog and a plastic spacer used to keep the cluster tight.


Refilling an oil bottle with a fixed cap. You need to squeeze the small oil bottle before dipping it in the oil, then let it inhale the oil. This can be repeated a few times. In between drinks, the oil bottle should be held right way up before inhaling again.

Finished bike.

Monday, July 19, 2021

Fixing fifty bikes, Bike 20, Shogun Metro SE

 





Hi

This bike was on a dumpster pile in Abbotsford, and I checked it out on the way to do my regular shopping on my recumbent leaning trike. I thought it would be ok for Wecycle so went back via the same street on the way home and the bike was still there. The chain was rusty, there were cobwebs, the right gearchanger and brake and the handlebars were manky, but otherwise good.

I managed to get it home ok, but needed to plan it as my usual route involves busy road with a steep uphill and downhill. Not the best route for riding home while steering and  braking a recumbent with the right hand, and steering and pushing a rescue bike with the left!

But the new route did involve a small stretch along busy Johnson St, which I managed to pull off fine despite some wind.

The bike is big, about 56cm, and I found a broken spoke when investigating an out of true back wheel. Fixed that by replacing one spoke and twiddling a few others. Replacement parts were a handlebar, a set of handgrips and the front gearchanger / brake lever.


Tuesday, July 13, 2021

New Bike Part 2

 

Previous site for suspension block was on

This modular bike frame, now in storage.

This was the part before modding, the source bike's purple colour can be seen in the metal parts.

Starting to cut it in half in my lathe.

Starting a drilling and cutting jig. By this time, the drill had been modded by adding a timber plate underneath. This plate makes an even surface for clamping.

Jig on cut suspension block halves.


One block sawn, one to go. Bike brake block included for shape and size comparison

Done!

This post shows the making of the suspension blocks for my new bike. See previous post for where it is to be used.

Monday, July 12, 2021

Bike 19, Malvern Star with Positron 2

 


As donated at Wecycle. In the background is Mike, helping a customer with a free bike, and in the back-background is Anna, interviewing a social worker about the value of bikes to her clients.
Positron 2 gear mech, woohoo!

Hi

This is the bike I rode home from Wecycle on July 10,  after dropping off the Giant Sedona. I changed the tube in the rear tyre, and it was ready to go really. Closer examination at home shows it has Positron 2 gear mech, indicating the bike is from the mid 1970's. It works ok but doesn't change into the lowest gear. I will do a bit of cleaning but am loathe to adjust settings on the derailleur, as I may not get it to work as well again. 

Despite its age the bike looks to have been well-serviced so there shouldn't be too much work to fix it.

Regards  Steve Nurse 

Update July 13

Managed to fix the gears so all are selectable now. Also found this website, with probably as much Shimano Positron 2 detail as you would ever need to know. This bike does not have the full catastrophe of Shimano Positron parts, for example there's no clutch on the chainrings. Its still interesting though! As well, the bike has pedals with toe straps, which I've tried and manage to get along ok with.

What does this thing do? Thankfully I turned this adjustment screw the right way and all the gears are working now. Adding a few chain links meant the chain isn't too tight on big / big or too loose on small / small cog combinations.

Handlebar controls.


Here is the serial number for those interested, M5C12936

Sunday, July 11, 2021

New bike part 1

 

Spare front part of bike was

reworked to have a new hole for a bottom bracket.

This was to simulate the layout of my new bike, and to test bottom bracket positions.  I want to have the bottom bracket as far forward as possible to keep weight on the front wheel.

This pic shows there's not enough clearance of the chain to the smallest sprocket with the bottom bracket forward of the steerer tube, so

its position will be  a bit like this, just behind the steerer tube. Brakes will be disc and calliper, so there is no need for clearing a v-brake boss on the back of the fork.


Hi

For a few weeks, I've been gathering parts for a new bike, with the most exotic a new front wheel drive recumbent fork from Performer. While I've gotten on ok with my leaning trikes for a while, a few issues have come up which maybe could be improved on a bike. This construction will use some parts (rear generator wheel, parts of rear wheel frame) from a bike I rode on the Murray Tour Audax 1200 in 2014. 

A few things got me motivated. 

* Want to get more weight on the front wheel. There's a bit of slip on the trikes' front wheel because there's not much weight on it.

* Want to standardise wheel size to 406 rims. This is the standard BMX size and super common, with many good tyres available from Schwalbe. The 451  / 20" rims I have on the front have been hard to get good tyres for, and the tyres on the back are a different size, the 349mm Brompton size. Good tyres are available for this size, but they're different from the front.

* Want to have a generator on the bike, and there is one on the back wheel I plan to use.

* Might be possible to save weight on the whole build especially the seat and rear wheel assembly. Will report more later.

Update July 12, 2021

Today I drew some schematics of what I have in mind for the rear suspension and some screen dumps are below. The rear frame will be supported on suspension blocks which are held inside the  frame. They have already been made and I will report more soon.





Monday, July 5, 2021

Bike 17 and 18, Giant Sedona and Upland SE

 

Giant Upland SE.....

was taken to bits in the back yard......

including the back wheel bearings and clutch. Both were full of muck old grease, and the clutch was slipping. Washing them out, and the clutch started working. Now its just putting it back together again.


Giant Sedona


Hi

Last Saturday I rode a recently repaired OzCycles bike to Wecycle, and rode home on a Giant Sedona, in need of fixing. This meant I could ride up to Wecycle on the roads, as I stick to bike paths when I'm riding a recumbent and wheeling a bike at the same time.

Then on Sunday there was a Giant Upland SE at the end of the street. Tyres were flat and it wasn't locked so I considered it abandoned and took it home.

Will report on how the bike repairs go. I like the Sedona better than the Upland. It's more of a commuter bike and doesn't have knobbly tyres. 

Following pictures are of Sedona: swapping the smallest 11t cog on the cluster

Soaking the crankset (not the pedal) to clean it up

Old bottom bracket bearing

was rusted due to water in the frame

Removing the seatpost. There is a block of wood under the frame, and the steel bar was struck with a hammer. Before this was done, the spots where the seatpost meets the frame was oiled, and boiling water was poured on. This helped the oil penetrate. All this moved the seatpost, then ...

It was waggled using a 12" shifter. A steel tube slipped over the shifter increased the torque.

One removed, the seatpost and inside the frame were cleaned.

Update 11 July

The Sedona has been delivered to Wecycle now. I rode it to Richmond to pick up our car after it had been serviced, and found out high gear was clunking. I only needed to change 1 cog to fix it. The bottom bracket bearing was rusty and I replaced that, and as well loosened the seatpost. The fixed stem was replaced for an adjustable one. I enjoyed riding it, and riding it to and from Wecycle was a good way of finding the problems and confirming they were fixed. The Sedona was allocated to a client too, so soon it will go to someone who needs it.

Still need to fix the Upland, and now 2 more bikes are arriving from our neighbour Stu. Will report later.

Regards

Steve Nurse

Thursday, July 1, 2021

Fixing 50 bikes, bike 16, Giant MTX

 

After

Before

The bike's sibling, another giant MTX with a much more common frame. Ganesh is fixing it while chatting to Mike. 

Fixing the back brake: it took a while!  The cable inner was stuck in the outers, and it was lucky I found this doodah  inside the shed that let me keep the cantilever brakes instead of swapping them for V-brakes.

 

 

 

Hi

The pics show the latest bike I've been fixing for Wecycle. Its a Giant MTX 24" bike with an interesting frame, certainly much more interesting than one of the more recent MTX's at the shed.

The fixing I did in the time I had was to swap out the wheels, (rear cluster was frozen) gear cable (ditto frozen) and chain (ditto frozen) and seat, and note that the seatpost was stuck.  After my work, it needed a cleanup, brake adjustment, seat de-sticking. Mike had already allocated it to a refugee family, so there is a "pull" to get this bike finished and out of the shed.

Update July 3, 2021. Today I worked on the bike again. The rear brake wasn't easy to fix and as well the seatpost was stuck. I'd lubed the seatpost and it still wasn't moving so took it inside the shed where Simon hit with a big hammer. It moved, but moved in, and we wanted it out!  Anyway it was at least "unstuck" and after that I was able to put a vicegrip on it, waggle it, and eventually get it off. With Jack's help. After that it was all done, and it was fun if a bit small to test out.

Regards

Steve Nurse