The Beast maintenance/upgrade

[lkingscott]

In case anyone hasn't noticed, I've been posting on the Folders topic about a Brompton which I've been repairing / restoring for a friend.

https://yacf.co.uk/forum/index.php?topic=124758.0

So having posted that project, I thought I'd post some maintenance / upgrade work I'm doing on my trike.

I built this trike 12 years ago and since then have put somewhere over 25,000km on it. Friends nicknamed it The Beast as at over 50kg,  it's the heaviest bike/trike they've seen.

It's built from 3 kids 24" bikes and originally most of the parts came from those bikes, even the gear shifters.

Over the years I've changed and upgraded only a few things, but most of it hasn't changed much. It originally had a leather office chair, but that disintegrated pretty quickly when it got wet, so I replaced it with a folding sun lounger. The brakes were the most significant change about 3 years ago, I welded on the brackets to convert it to disk brakes. It's amazing how much better it is now it stops when I want it to, particularly with over 50kg of momentum!!!

The gears and drivetrain need some significant maintenance and while I'm at it I'm finally upgrading the bottom bracket bearings. The old loose balls lasted only a few months between adjustments, so I decided external bearings and a Hollowtech crank should be the answer. I want lower bottom gear too, but didn't want to compromise the top gear, so with the new smaller main chainwheel I needed smaller freewheel top sprockets. That's plural, because it has 2 rear freewheels, one in the middle and one at the back. With 7 gears on each, that makes 49 gears!

Today, I got the old bottom bracket apart, which needed some heat due to the thread lock. I managed to get the new BB bearings and crank in place too and removed the mid shaft and gears.

As I'm finally getting around to improving the gearing, I decided it's also time to straighten the mid shaft. I made it from a rear wheel hub, which I cut in half and welded a tube between the halves. I had no lathe then, so aligning the parts was a bit hit and miss. Anyway it was a bit wobbly but worked. A couple of years or so ago one side wore out. Amazingly the bearings carved their way through the bearing shell!!! So I only had a spare front wheel hub at the time and I needed it fixed, so I welded that on. The bearings are smaller, but it's been working fine and that end is welded on nice and straight.

I 3D printed some plates to fit the front chainwheel, as can be seen. I think I'll do the same for the mid shaft chainwheel.

So that's where I am, mid shaft in the lathe, just measured with a dial gauge about to cut and reweld straight!

Here's a few pics...





The boot takes 2 crates of beer...

[lkingscott]

Before anyone asks why I built it the way it is...

I wanted a semi recumbent for comfort riding to work every day, but high enough to see and bee seen, with a lockable boot for shopping, and a trike so that I could ride even in the snow, without the risk of falling off when the slush refreezes at night and the bike tyre tracks turn solid to take your wheels from under you.

Yes, the height introduces some instability, but the only time I've fallen off was riding over a black painted concrete block in the dark. I think anything would have had an issue with that!

The >50kg weight gives a good workout too!!!

The semi recumbent position for me is so much more comfortable than the leaning forwards but head cranked up position of diamond bikes. I discovered only last year I had a herniated disk in my neck, which could have started years ago and was probably what started me down the track to build it!

[Kim]

Wow, that really is a beast! 

IME being a bit higher up makes a big difference to the practicality of a recumbent for utility riding, where you don't want to be splashed by passing cars or blinded by every oncoming headlight.  It's not like you're going to be doing any extreme cornering on a machine like that.

[Tim Hall]

Wow, that really is a beast! 

IME being a bit higher up makes a big difference to the practicality of a recumbent for utility riding, where you don't want to be splashed by passing cars or blinded by every oncoming headlight.  It's not like you're going to be doing any extreme cornering on a machine like that.

Is that the sound of a gauntlet being thrown down?

[lkingscott]

Wow, that really is a beast! 

IME being a bit higher up makes a big difference to the practicality of a recumbent for utility riding, where you don't want to be splashed by passing cars or blinded by every oncoming headlight.  It's not like you're going to be doing any extreme cornering on a machine like that.

 

Yes, I like the idea technically of a low down 'bent, but I'd be scared s'less in traffic, especially trucks!

[Lightning Phil]

Bet it’s like shit off a shovel downhill with all that weight.

[numbnuts]

The Beast as at over 50kg OMG, I thought my KMX was heavy, I'll sleep better tonight knowing mine is lighter.

[cycleman]

My sun es3 trike is probably a similar weight with its high tensile steel frame. The beast looks ba bit bigger 

https://photos.app.goo.gl/vfhBgGdiDgwhWEyp9

[lkingscott]

Bet it’s like shit off a shovel downhill with all that weight.

 

Oh yeah!!!

Particularly since I changed to disk brakes..!!! I'm amazed how little the pads wear down, still the same pads after 2.5 years and a thousand or so km. The old rim brakes would last a month or 2 and were a complete PIA to set up. The disks are fantastic, including adjustment or resetting if I remove a wheel.

[lkingscott]

My sun es3 trike is probably a similar weight with its high tensile steel frame. The beast looks ba bit bigger 

https://photos.app.goo.gl/vfhBgGdiDgwhWEyp9

Sunseeker web site claims 56lb for the front handlebars and 65lb for the side steering bars versions. So that's 25 to 30kg, but your pic also shows a trailer which will bring that weight up.

I love the big seat for comfort, but when it's windy it gets really hard work into wind, so I am thinking of options to change the seat back tube shape to make it lower and narrower. It doesn't need to go above my neck level and could be narrowed 10 to 20cm.

I also got a specially shaped umbrella for it in China, you see people riding mopeds with them in the weather there.    I tried the umbrella for a while, but it didn't do much for the rain when moving and felt a bit unstable in strong wind.

[lkingscott]

The Beast as at over 50kg OMG, I thought my KMX was heavy, I'll sleep better tonight knowing mine is lighter.

 

I was doing 15 to 20km a day or more to work and back, including a pretty significant hill on the way back, until mid 2016. Since then I have done a bit less on it, but still do the occasional longer trip. In October last year I did a day trip on it over 60km. It was mostly flat and no wind, but it still felt like double that compared to a similar distance on my old 20kg 2 wheeler. I've also moved 5km further from the city centre, so expect the regular distance to increase.

The main issue with the weight (and size when it's windy) is that it is slower than a 2 wheeler, although whenever I get myself fitter I do overtake many 2 wheelers. I keep having to talk myself out of adding an electric motor as I need the workout!

[lkingscott]

On the lathe I found there was about 1.6mm of runout on the edge of the new freewheel gearset.

I cut the tube half way and with a bit of force, got the runout to less than 0.2mm. The hacksaw didn't seem to be cutting very well after a bit, you can see why in the pic!

After welding, grinding, phosphoric acid treatment and painting, it looks pretty good.

I want to 3D print some side plates for the outer sprocket on the mid shaft. The chain doesn't normally jump of but it's a PIA when it does.

[lkingscott]

Well I got it all back together with the new chains and gears and started using it. I 3D printed chain guards and when I first put it together, due to the bigger sprockets, I had to move the half shaft about 10mm further out. This then necessitated a mod I should have done years ago. As the slot for the axle is in line with the pull on the chain, it has to be torqued right down. I added a plate with a bolt threaded into the end plate. Not only does it locate the shaft exactly, but it prevents the axle from ever pulling out.

I have had exactly the same problem with the rear wheel, due to the disk brakes. I therefore did the same for this.

As I used it, I just couldn't get the gears properly adjusted and then yesterday, as I went to pull away from a junction, I did a road runner impression!

A quick look and I could see the problem. The half shaft is made from a wheel axle (actually 2 dues to bearing wear on one end which went right through) and the sprocket on one end was not moving with the shaft. It turned out the wheel hub was pressed together and the extra weight of the trike made it come loose.

So I took the half shaft off again and welded right around the press fit joint, after aligning it with a dial gauge on the lathe. I sprayed it up and refitted today. While reassembling, I noticed that the sprockets on the half shaft had been gradually winding themselves further and further onto the half shaft, thereby causing some of the gear alignment issues. A large washer fixed this!!!

So here it is all working nicely.



I cut this bolt short, but this was good for an initial test.

[lkingscott]

BTW, those plates are made from the brackets which used to hold my fence together. The trouble with working with metal, every bit of scrap metal becomes potentially useful, so one tends to become a scrap hoarder!!!

I suppose the same can be said for wood... I have quite a stack of wood too...!!!