WC2024 - World HPV Championships - a folly to far ?

[Popshot]

Given the steering follows the front tyre the fork is not the alignment issue. Either the headtube is not square to the chassis or the back axle isn't. Either way getting something on the frame just behind the front wheel to twist it straight compared to the back wheels will fix it. I have a 3 foot pipe wrench for such tasks.

On the other hand if you race on anti-clockwise tracks the slight lean may be useful as will the offset rear axle as they will both add to stability. A bit of a downer on clockwise tracks though. You could build a mirror image machine for those tracks. In all seriousness Paul such a machine as you currently have could be an advantage on left handed circuits. Nascar race cars are set up for the corners not the straight and that trike could be faster as is than straightened out on a left hand circuit.

 

[stormbird]

I press on despite the deadline slipping through my fingers...

So this is what I have achieved a parallel chain line in the middle ring ?

the wood is the quickest way to find a sweet spot for the pulleys , although it has now been replaced with 3 exhaust clamps , 2 around the head tube and the one shown holding the wood now has the smaller pulley fastened directly to the upper leg.

The power side pulley needs to be mounted somewhere on the green dotted line , gut feeling the higher the better although the chain may then bend through greater than 90' to get to the cassette ? is that bad ? answers on a postcard.

So mount big pulley and add some chain , see what new problems present themselves maybe by Sunday.

Paul

 

[stormbird]

So nearly there :-

Bit clunky [ but hey no wood ] and very adjustable , if it can take the strain of being ridden to see if these can work.
So 2 x 34mm clamps hold a vertical piece of tubing maybe 15mm x 10mm anyways strong enough for a M10 hole through it for the drive side pulley mounting bolt. The upper M6 will be sawn off and the mounting bolt will be just above it with a flat of the bolt head resting on the clamp [ to stop it turning ] whilst lock nut wound on.

Chain line may look something like this ,with the black pulley a little higher.
You can also see the swiveling pulley mounted on a 32mm clamp for the return side of the chain , also adjustable.

So one more hole to drill and I can look at getting the chain on.

Paul

 

[DannyC]

So nearly there :-

Bit clunky [ but hey no wood ] and very adjustable , if it can take the strain of being ridden to see if these can work.
So 2 x 34mm clamps hold a vertical piece of tubing maybe 15mm x 10mm anyways strong enough for a M10 hole through it for the drive side pulley mounting bolt. The upper M6 will be sawn off and the mounting bolt will be just above it with a flat of the bolt head resting on the clamp [ to stop it turning ] whilst lock nut wound on.

Chain line may look something like this ,with the black pulley a little higher.
You can also see the swiveling pulley mounted on a 32mm clamp for the return side of the chain , also adjustable.

So one more hole to drill and I can look at getting the chain on.

Paul

Getting perilously close to being ridden.

 

[stormbird]

It has been ridden AND as predicted [ above ] is perilous

Trips involve out the cul-de-sac into the estate down to the bottom of that street 180' turned followed by 3 x 90' and back onto the drive [ IIRC all of 250 meters ].
First ride it was all over the place in a sort of trike maybe steering and I may not be , most odd.
Turns out rear wheels were not fastened properly and one had lost it's retaining nut and the outer bearing , I think a last minute panic to use the rear wheels on my trailer for the Netherlands was the cause. I put the correct wheels/washer & lock nuts and ventured out again. There were no brakes the first time so it was very hairy - odd how 6mph can feel scary ! This time I had my faithful rigger gloves so i found I could use my hands on the floor if need be [ it is a real low racer ] and also use them for brakes.

Next ride was better and I immediately noticed there was NO pedal steer at all , it was very well behaved and the chain complained a bit however it stayed exactly where it was meant to be , reassuring. there is a very slight heal strike if I try to turn tightly , easily lived with and of course not likely racing. If it is moved or pedaled backwards it will sometimes change gear at the cassette however as soon as you pedal it goes back to where it should be. As you can see the chain is parallel to the fork on the drive side and the return pulley is also clear of the wheel.

Everything is more in line that this pictures suggest. On the right the chain ring needs moving out a little to try and get the chain more parallel
to the main boom , however it does work so maybe leave it for now as there is still lots to do.

The angle coming into the cassette from the big pulley looks steep , almost all kids bikes do not have may gears at the rear and only one at the front because of the chain line , now the Python works well and the BB to axle centre is 15.5" , this has 16.5" between black pulley pivot and axle so right in the ball park.

next up I need a real brake and to look at handle bars , DannyC and I had discussed making them the same as the stream-liners Beano , Snoopy , Woodstock and NoSo as it is simple with no ball joints and very light. It just consists of bars attached directly to the bottom of the forks and ending in a place they can be reached ?

This is Beano the wheel is inside the fairing on the left and this is the right hand handle bar , it could be impossible to make work if I can't find a place for my hands that is comfortable for my seating position and gives me ALL the turning circle available.

A quick and dirty spin on the front garden showed a potential to turn a circle with a inside diameter of only 5.5ft at the inside rear wheel , that is small

Oh and currently it weighs a whopping 16kg , strewth where has all that weight come from ?

Still plenty of places to lose some from , however 2kg is a tall order that's 15%

Paul

 

[DannyC]

Congrats on your escape from a test ride unscathed.

 

[stormbird]

So par for the course the fixing of one problem just begets another , meaning more parts making/welding & fettling with no apparent forward progress at all ?

The piece on the left was added to move the axle backwards to get it's centre line closer to the centre line of the fork , hence the trikes nicer manners. Now when looking at it , it becomes apparent that the axle now is about 3mm lower than the original build , surely of no consequence ?

However the manufacturer decided when attaching the brake posts that the brake shoes should be at the very bottom of the adjustment slot and not as any sane person would think ' in the middle of the slot ' ?

So I cannot get the brake arms on as the shoes are touching the tyres !!!

So after throwing my toys out of the pram I came up with this fix , the hatched piece will be a new piece of metal welded in blocking the existing slot.
A 8mm hole will be drilled where the dots are at the top of a new slot that will be cut with a grinder. This should allow the wheel to go in vertically could allow the wheel out easier ? At the same time this makes the slot inline with the fork centre axis and not slightly behind it.

Maybe I have built the first low racer than needs lawyer washers for rider safety ?

Paul

 

[stormbird]

A re-assessment made me realise I had also added 3mm to the forks when I made them wider to take a rear wheel , so maybe the plan wasn't great after all ?

However there is always a plan B ? drop one of these on , it takes most of the hard work out of brake pillar spacing ?
I can line up the hole at the top and add the brake arms/blocks and clamp the whole thing in place with Jubilee clips for welding.

So this is left side block about in middle , the block look a little odd I think because the wheel is only 16" in diameter.

.. and the right with some ugly welding visible.

I took the opportunity to build a better rear wheel where it is better centered in the forks and hopefully will eliminate the annoying cluck I got from the transmission every few yards.

We shall see tomorrow I hope.

Paul

 

[stormbird]

So better attempt at traditional handlebars and other hardware added......

So we have brake hardware installed however we don't have a brake only a retarder , needs some fiddling as it cannot currently stop the device.

The less cluttered side , looks clean from here.

As there is a huge amount going on here , I did manage to derail the chain today [ first time ] sat on it with maximum right lock and walked it backwards after some clattering it fell off the crank ring. A reminder it needs guards and I need my front wheel disk on to stop the mess ending up in the spokes. Yes you can go over the handle bars should you lock the front/rear wheel at speed.

This is the view from the cockpit at about eye line so plenty of vision however the bars can be lower still when I have attended to other matters.

I have expanded the rides now with my new found slowing power and I/it has now done 3 rides of 561m so 1.3 km or about 1 mile.
Many many things need attending to , in no particular order:-
1) I noticed small flecks of black plastic on my legs - the chain is chewing it's way through the black pulley at a tremendous rate !
2) Seat needs to be further forward - in my ' non cycling shoes I am hitting the derailleur with my heal:-

So I hope to get cranks further forward and this should go away.
3) very hard to get any gears - Hanger needs bending outwards a little [ why I can't get the lowest gear ] H & L stops need adjusting.
4) I noticed a slight swaying maybe only 1/2" when attempting to turn I found numerous bolts loose on the rear axle AND the seat not helping.
5) It seems to feel as though it wants to tip over - well it hasn't and probably can't easily however with a 8" seat height and 24" rear track I expected to have more confidence/faith in it than I currently have - seat time and a couple of of sh*t moments should sort that out.

Should I be worried about the brake arms ? they seem to be pointing into the centre of my calf muscle , I think it could really spoil your day if they did make contact !!!
Moving the seat forward moves the crown jewels ever closer to the vertical frame member , should I really worry about this ? I mean if I should have an ' episode ' will 2.5" of space there really save me ? The seat is in front of them just.
It is much better at dealing with camber changes especially now it does not ' sway ' from side to side as you traverse the camber.


DannyC and I have been discussing the possibility of rear wheel drive using something like this :-

It is an Italian designed rigid axle for a pedal car.
So no diff just a cassette & free wheel tied to a M15 axle going through 2 x pillar block bearings , they say no problems if track width is kept narrow , as I am shooting for less than 18" it should be fine.
Pro's :-
front fork much simpler
much easier to get good gearing
Con's:-
all that chain
chain has to pass under seat
possible more weight

As an aside I bravely remove my hands from the handlebars and continued to pedal - it went as straight as a arrow - that's a relief should be less tiring to ride if I am not fighting to keep it on a course.

Paul

 

[undertoad]

should I really worry about this ?

Probably OK, as long as your feet are firmly in those clips.
OTOH, maybe a bit of padding, only as a failsafe precaution, you understand, might be reassuring

 

[stormbird]

Problem 1) being addressed ?

As you can see the idler is self destructing and covering me in black plastic !

Current solution is to mount a pawl-less free wheel to the same hardware the idler was on [ it will be made permanent when proven ].
Perceived wisdom is you don't need a full complement of balls nor does it have to be well greased used as a freewheel as it spends most of it's time pawls engaged not turning per say and driving the wheel......
Not anymore baby ! it is just not turning now when the pedals are not moving , else it is under power , it becomes quite noisy in the lower gears [ compared to the pulley ] as the chain speed increase other than that it seems to work OK on the 2 brief rides I took yes another 1km done.
After many chats with DannyC the gearing has been chosen a 14t - 28t with a 42t for riding around the homestead and a 62t for racing [ yer right that is likely to happen ] estimated current top speed @ a modest 80 rpm is only 16mph . Not ground breaking although more cadence is possible for a short burst , changing the gearing to get more speed maybe harder and I might not have the time as there are other problems to attend to ?
I added the 42t it will be hand changed , now need to fix the chain length for it to work it seems very looong at moment
Paul

 

[stormbird]

So today I set out to improve the gearing , and yes a 8 speed screw on freewheel almost fit :-

Not quite enough clearance for the 8th gear , out with the grinder and ...

Viola we have a new cassette rear mech from somewhere or other and a s/h trigger shifter and we almost have 8 gears , will change to the lowest however not for long before it moves to 2nd [ I think the cable length needs tweaking ] however this is about 5 more gears that I have had in the past so a trip is in order !
I decided to visit a friend and enormous 750 meters away 1.5km round trip.
Did I make it yes.
Was it good - actually no it was truly dreadful !!!

It bangs and cracks and creaks and is extremely noisy , ok the chain did not come off and it got me there and back but there was absolutely no joy in the ride at all. I though this was all down to chain [mis]management however it did a couple of nice noises whilst just freewheeling so what to do ?
Also I could not get the lone brake to look like it was happy at all ?

having spent far to long trying to figure out why it wanted to settle like this I gave up.
It really needs two brakes anyway so the best idea is to add some to the rear end ?

So this is how much steel will be needed and roughly where it needs to go , so next job maybe tomorrow ?

Paul

 

[DannyC]

So today I set out to improve the gearing , and yes a 8 speed screw on freewheel almost fit :-

Not quite enough clearance for the 8th gear , out with the grinder and ...

Viola we have a new cassette rear mech from somewhere or other and a s/h trigger shifter and we almost have 8 gears , will change to the lowest however not for long before it moves to 2nd [ I think the cable length needs tweaking ] however this is about 5 more gears that I have had in the past so a trip is in order !
I decided to visit a friend and enormous 750 meters away 1.5km round trip.
Did I make it yes.
Was it good - actually no it was truly dreadful !!!

It bangs and cracks and creaks and is extremely noisy , ok the chain did not come off and it got me there and back but there was absolutely no joy in the ride at all. I though this was all down to chain [mis]management however it did a couple of nice noises whilst just freewheeling so what to do ?
Also I could not get the lone brake to look like it was happy at all ?

having spent far to long trying to figure out why it wanted to settle like this I gave up.
It really needs two brakes anyway so the best idea is to add some to the rear end ?

So this is how much steel will be needed and roughly where it needs to go , so next job maybe tomorrow ?

Paul

Is that already at the narrowest track you are likely to use?

 

[stormbird]

Is that already at the narrowest track you are likely to use?

One word answer ?

No

Paul

 

[Popshot]

Tell me those calipers are just for the mock up. and you have something better for actual use.

 

[stormbird]

Tell me those calipers are just for the mock up. and you have something better for actual use.

Err sorry nope.

So out with the new and in with the old , least now I have 2 brakes and NOT on the front wheel. That simplifies the fork a bit , and doubles the braking power.
Honest.
I don't think the levers work very well with the side pull brakes , they are capable of locking the wheels however they are very hard to pull , need to investigate that further also I want better brake shoes still on to the next problem.

The loud creaking/cracking noise is still there , so next up I will drop the chain and fit a front wheel , I will walk it further up my estate so I can get to a place where it can free wheel maybe that will prove the noises emanate from the current wheel.

Did another 1km brake testing and listening to it's various noises , try handlebars in a different position [ further forward ] unsure what that brings to the party .

Paul

Ps I do have a Weinmann 947 however only 1 , can't see another on Ebay.

 

[stormbird]

Riding hands off has appeared to be a ' false dawn ' of mega proportions [ all BAD ! ] It turns out the temporary free wheel/pulley mount had a nut sticking out of it that was flush up against the knurled steering race nut and was stopping it moving ? I foolishly decided to remedy that this morning. Well guess what it was doing a very important job. Now it cannot be ridden hands free has a sort of tan slap motion when free wheeling and when pedaling hands free it heads for the left curb asap. Also now when you pick the front up the forks swing around under the influence of the chain. So the pressure of the nut was enough to stop the knurled part moving forcing the forks to screw in and out of it , this was enough ' steering damping ' to provide the amazing handling I experienced. I may add that bolt/nut back and set it up like that , can't seeing it doing much damage to the parts ? in the short term.

Paul

 

[stormbird]

As DannyC pointed out from the description I gave the steering now behaves like one of those annoying shopping trolley wheels that shimmies violently left and right without try to do a 180' so what to do.

I must say i was really low on Tuesdays call [ sorry DannyC ] however looking around the sheds cluttered with yesterdays successes I realised if I was to save this low racer it needed something radically doing to the front end ?

Putting the Mk1 Python front end on the rear luggage carrier i found spookily the w/b was identical so Tuesday night they were both beheaded !!!
Some grinding and welding today gives me back a low racer ....

Now I vowed never to race a Pythons as they can be difficult to control at speed especially if free wheeling and this front end had very limited gearing available as:-
a) big ring cannot exceed 48T
b) drop outs to narrow for anything bigger than a 7 speed cassette
c) crank rings are limited as the offset is important

The answer ? fit a Nexus 7 IGH that way I can change the gearing by changing the sprocket , as for the speed as long as I have more gears at the top end available I should be able to control it , and a direct drive [ 20 GI ] and 1 step below should be nice for the hills around here.

It is getting a bit portly @ 15kg [ incomplete ] however there is some scope for shedding some weight IF it works.
So Thursday/Friday is chain/controls day Saturday/Sunday testing Monday trip to mum's or complete failure of this project.
It is as stark as that.

Paul

 

[DannyC]

As DannyC pointed out from the description I gave the steering now behaves like one of those annoying shopping trolley wheels that shimmies violently left and right without try to do a 180' so what to do.

I must say i was really low on Tuesdays call [ sorry DannyC ] however looking around the sheds cluttered with yesterdays successes I realised if I was to save this low racer it needed something radically doing to the front end ?

Putting the Mk1 Python front end on the rear luggage carrier i found spookily the w/b was identical so Tuesday night they were both beheaded !!!
Some grinding and welding today gives me back a low racer ....

Now I vowed never to race a Pythons as they can be difficult to control at speed especially if free wheeling and this front end had very limited gearing available as:-
a) big ring cannot exceed 48T
b) drop outs to narrow for anything bigger than a 7 speed cassette
c) crank rings are limited as the offset is important

The answer ? fit a Nexus 7 IGH that way I can change the gearing by changing the sprocket , as for the speed as long as I have more gears at the top end available I should be able to control it , and a direct drive [ 20 GI ] and 1 step below should be nice for the hills around here.

It is getting a bit portly @ 15kg [ incomplete ] however there is some scope for shedding some weight IF it works.
So Thursday/Friday is chain/controls day Saturday/Sunday testing Monday trip to mum's or complete failure of this project.
It is as stark as that.

Paul

We are all wishing you every success Paul.

 

[stormbird]

No pictures as nothing has changed [ yet ] however seat moved forward 2" front derailleur working , as Nexus 7 defaults to low gear that means I can ride it around with those 3,
So brakes working and off we go , not drama ' hey it's just a Python after all ' , couple laps around the estate nice and quite good handling and turning circle adequate [ i.e much more nimble than a tadpole [ sorry DannyC not intended for you ].
next up need IGH cabled up and working then look at changing seat ...
Wish I could find the speedo for it , that would be good.
Monday looks within reach at moment.

Paul