WC2024 - World HPV Championships - a folly to far ?
- Thread starter stormbird
- Start date
Zipp one gives better steering as the chain pivots about the steering axis. Need up to ±20° for some corners! The one pulley is for a 2 wheeler!
Also very hard to add any guides for the crank ring as there is no chassis anywhere closeI agree with @Popshot the second one looks a candidate for chain skipping.
Yes 1 looks better certainly for me on the streets , however a few racers Jeff James for instance has remove his chain from the return idler.
Not possible to see the correct side of his bike however you can clearly see the return side chain does not come off a pulley
He does say however that it will derail if peddled backwards not sure I have the discipline to remember that
Interesting your ±20° I was sure all the stream-liners are happy if they achieve ±10° maybe they corner wide ?
Paul
So mulling over the rear axle problem , that in all honesty could be easily made by the Southern lathe boy [ you know who you are ]
I found a non lathe solution amongst my parts...
So in upper left is some electrical conduit which has printed on it 25mm
Inserted is a M12 coupler outside is 19mm - a snug fit
Washer wheel [ shown by wood ] washer and lock nut - all assembled on a length of M12 threaded rod running the full width of the axle.
Loosely assembled we look like this , this is 24" between tyre centre's now this is the training axle used whilst we get the FWD tamed and
some seat time ultimately I want an axle only just smaller than my across the shoulder width.
Now it would be nice if I did not have to keep building a new one as I move down say 20" then 18" any maybe 16" !
I realised if I only welded one of the M12 couplers in the tube the other could simple be locked by a normal M12 nut snugged up to the coupler before the washer - wheel - washer - lock nut.
Shortening the axle then just involves shortening the outer tube , re-assembling the loose coupler and shortening the M12 all thread.
Simples
As shown the assembly weighs 3.2kg and the front end weighs 9.18kg = 12.38kg however we are short of cranks,chain and brakes at this point
I think there is some room for lightness ?
That tubing must have a thickness of 25mm - 19mm = 6mm so 3mm wall , I am sure 1.5mm wall would be strong enough.
Interestingly the wheels as show alloy hubs [ narrow ] Schwalbe road tyres are 1 kg , not sure there are any racing tyres in 305mm which could be lighter ?
So tube + bits must weight 3.2kg - [2 x 1 kg] so 1.2kg
Of course if I chopped it down from 24" to 16" that could reduce the weight by maybe 0.6kg so heading in the right direction.
Still a long way to go , however it seems more likely to work than the pedal car !!!
Paul
]I found a non lathe solution amongst my parts...
So in upper left is some electrical conduit which has printed on it 25mm
Inserted is a M12 coupler outside is 19mm - a snug fit
Washer wheel [ shown by wood ] washer and lock nut - all assembled on a length of M12 threaded rod running the full width of the axle.
Loosely assembled we look like this , this is 24" between tyre centre's now this is the training axle used whilst we get the FWD tamed and
some seat time ultimately I want an axle only just smaller than my across the shoulder width.
Now it would be nice if I did not have to keep building a new one as I move down say 20" then 18" any maybe 16" !
I realised if I only welded one of the M12 couplers in the tube the other could simple be locked by a normal M12 nut snugged up to the coupler before the washer - wheel - washer - lock nut.
Shortening the axle then just involves shortening the outer tube , re-assembling the loose coupler and shortening the M12 all thread.
Simples
As shown the assembly weighs 3.2kg and the front end weighs 9.18kg = 12.38kg however we are short of cranks,chain and brakes at this point
I think there is some room for lightness ?
That tubing must have a thickness of 25mm - 19mm = 6mm so 3mm wall , I am sure 1.5mm wall would be strong enough.
Interestingly the wheels as show alloy hubs [ narrow ] Schwalbe road tyres are 1 kg , not sure there are any racing tyres in 305mm which could be lighter ?
So tube + bits must weight 3.2kg - [2 x 1 kg] so 1.2kg
Of course if I chopped it down from 24" to 16" that could reduce the weight by maybe 0.6kg so heading in the right direction.
Still a long way to go , however it seems more likely to work than the pedal car !!!
Paul
Popshot
0
As Dale Rider says though, there's a difference using that on a two wheeler to a three. Much less steering input with two wheels.Yes 1 looks better certainly for me on the streets , however a few racers Jeff James for instance has remove his chain from the return idler.
Not possible to see the correct side of his bike however you can clearly see the return side chain does not come off a pulley
He does say however that it will derail if peddled backwards not sure I have the discipline to remember that
Interesting your ±20° I was sure all the stream-liners are happy if they achieve ±10° maybe they corner wide ?
Paul
With about ±70° available , and frequently used , on the Python I can't say I have given much thought to ' you might have to little ' !
Whilst the pedal cars seem very nimble I have yet to try one on the street and so can't say whether they have enough or not.
So we plough on regard less...
Chain back on and seems to work pedaling backwards , can't go forwards as some idiot clamped the front wheel into the workmate ho hum.
Paul
Whilst the pedal cars seem very nimble I have yet to try one on the street and so can't say whether they have enough or not.
So we plough on regard less...
Chain back on and seems to work pedaling backwards , can't go forwards as some idiot clamped the front wheel into the workmate ho hum.
Paul
Needed a jig to drill repeatable holes in the different rear ends I can fit , been putting it off however it turned out to be very easy.
Arrows on wood upper/lower denote front of bike/trike , 2 in middle show 2 x M3 holes as pilots for tubing.
Important to get tubing in same orientation as holes were not as accurate as I would have liked , so steel also has ' front ' arrows and ' up ' sign.
This was slid onto stub sticking out of main tube [ with a small gap left ] and M3 holes transferred to stub , all holes then drilled to M8.
Just held for testing with M8 QR's however they will probably become M8 bolts and nuts as I have misplaced a piece from 1 of the QR's.
So chain is now on [ pulleys position not yet optimised ] as it has yet to be ridden.
Dropped a rear wheel on to look at position for WB 38" it is actually sat about 4" to low to work.
Next up build rear axle and get a gear changer on ...
Oh and sit on it for pedal/leg clearance investigation.
Paul
Arrows on wood upper/lower denote front of bike/trike , 2 in middle show 2 x M3 holes as pilots for tubing.
Important to get tubing in same orientation as holes were not as accurate as I would have liked , so steel also has ' front ' arrows and ' up ' sign.
This was slid onto stub sticking out of main tube [ with a small gap left ] and M3 holes transferred to stub , all holes then drilled to M8.
Just held for testing with M8 QR's however they will probably become M8 bolts and nuts as I have misplaced a piece from 1 of the QR's.
So chain is now on [ pulleys position not yet optimised ] as it has yet to be ridden.
Dropped a rear wheel on to look at position for WB 38" it is actually sat about 4" to low to work.
Next up build rear axle and get a gear changer on ...
Oh and sit on it for pedal/leg clearance investigation.
Paul
Rear end is in the works:-
I carried this out the garage in 2 parts for a test assembly , I though crikey this is heavy till I realised in trip one I had the whole of the front except the rear axle and was carrying it in 1 hand !
As shown above it is now @ 15kg with some components missing and some needing a weight reduction program.
Not pursuing that yet as no point unless it performs.
So rear will consist of this goose neck welded to the rear frame part , this will allow axles of different widths to be deployed without constantly messing up the frame parts at the back. i have welded a 3mm plate on top between hatched bit and blue arrow so when I come to weld this on it will be 3mm to 3mm and the plate will spread the load over a bigger area. Just need to decide how and where to brace the goose neck and the axle.
Rear frame left long to help me fasten it down for welding and heat dissipation.
It is these shots that excite/spur me on , it may actually work !
Almost out of gas , need to get that next week to allow it to be finished.
Paul
ps it gave me great satisfaction to wheel it into the garage in 1 piece
I carried this out the garage in 2 parts for a test assembly , I though crikey this is heavy till I realised in trip one I had the whole of the front except the rear axle and was carrying it in 1 hand !
As shown above it is now @ 15kg with some components missing and some needing a weight reduction program.
Not pursuing that yet as no point unless it performs.
So rear will consist of this goose neck welded to the rear frame part , this will allow axles of different widths to be deployed without constantly messing up the frame parts at the back. i have welded a 3mm plate on top between hatched bit and blue arrow so when I come to weld this on it will be 3mm to 3mm and the plate will spread the load over a bigger area. Just need to decide how and where to brace the goose neck and the axle.
Rear frame left long to help me fasten it down for welding and heat dissipation.
It is these shots that excite/spur me on , it may actually work !
Almost out of gas , need to get that next week to allow it to be finished.
Paul
ps it gave me great satisfaction to wheel it into the garage in 1 piece
I was chided this morning by someone who will remain nameless [ although his name does rhyme with Nanny ! ] as to why there was no progress posted in this thread.
Er because there hasn't been any ?
So the plan was to fix 4 problems with the front end/drive system.
1) head set bearings not seated properly - has the plonker made a rookie mistake and not got the balls in the cups [ makes your eyes water ]
2) big pulley not high enough and far enough forward
3) little pulley as above
4) chain rings loose and only 3 of the 5 bolts present
1) headset bearings were ok and the right ones and the right way around they were just hung on the lower race at an angle , straightened them and we were good to go.
2) So I have made a new bracket , screw on to make it easier to adjust/move and mounted the M10 pulley bolt on it further forward and higher than it had been.
As you can see the chain is still not parallel with the fork leg [ as per best practice ] that can't happen as the fork is to bulky at the bottom and has to much rake which moves the centre of the cassette forward. However it will become more parallel as the chain moves into the lower gears , not really useful as it's a racer and should be in the top 3 gears the most of the time
3) There is a circle draw just in front of the big pulley it will be drilled to M8 and the red pulley will be mounted on it and upgraded to a M8 rod end instead of the weedy M6 it has currently.
4) fixed.
I have lined the 2 pulleys up with the chain ring as the chain does not move from side to side between them and the crank ring.
The red pulley pivoting looks great and I hope is helping the chain stay on the derailleur lower jockey wheel.
next up fix some controls and try to find a solution to the handle bar leg/knee clearance issues.
Getting there ever so slowly Paul
Er because there hasn't been any ?
So the plan was to fix 4 problems with the front end/drive system.
1) head set bearings not seated properly - has the plonker made a rookie mistake and not got the balls in the cups [ makes your eyes water ]
2) big pulley not high enough and far enough forward
3) little pulley as above
4) chain rings loose and only 3 of the 5 bolts present
1) headset bearings were ok and the right ones and the right way around they were just hung on the lower race at an angle , straightened them and we were good to go.
2) So I have made a new bracket , screw on to make it easier to adjust/move and mounted the M10 pulley bolt on it further forward and higher than it had been.
As you can see the chain is still not parallel with the fork leg [ as per best practice ] that can't happen as the fork is to bulky at the bottom and has to much rake which moves the centre of the cassette forward. However it will become more parallel as the chain moves into the lower gears , not really useful as it's a racer and should be in the top 3 gears the most of the time
3) There is a circle draw just in front of the big pulley it will be drilled to M8 and the red pulley will be mounted on it and upgraded to a M8 rod end instead of the weedy M6 it has currently.
4) fixed.
I have lined the 2 pulleys up with the chain ring as the chain does not move from side to side between them and the crank ring.
The red pulley pivoting looks great and I hope is helping the chain stay on the derailleur lower jockey wheel.
next up fix some controls and try to find a solution to the handle bar leg/knee clearance issues.
Getting there ever so slowly Paul
Ok there is nothing to hide AND no where to hide so all my builds are warts and all.
because:-
a) I am looking for sympathy
b) I am looking for help
c) I am currently stumped
problems discovered so far are in at least 1 of the above categories [ and some are probably in several ! ]
I have ridden it briefly the same 280 meters the pedal car has traveled , although in all honesty the pedal car has done that trip more than once and is no where near as frightening as this contraption !!!
these problems are in no particular order:-
1) can't get all the low gears [ this has consequences [ see below ] - puzzling I cannot find the Low and High gear stops ! on the rear mech- it maybe because the mech is now rotated 90 ' and points horizontally instead of vertically ? not researched that yet
2) because I cannot get into the low gears whilst I have the power to cycle away from a stand still the torque steer takes you by surprise and send you veering all over the road. It almost feels like a MBB and it certainly shouldn't
3) the steering like the other bike I had with 16" front wheel is very quick - so you only need a small turn of the handle bars for a large steering input - this again takes you by surprise and with the next problem makes progress down the road in a straight line almost impossible [ at the moment ]
4) i think it is following the camber so when you come off the crown of the road it veers very quickly into the kerb - I have experienced this in the UK upright ' big wheel ' delta trikes most unnerving till you have mastered it.
5) I said to Nanny this morning it is tilting about 2 - 3 inches in either direction measured at the seat top - this is bad as you feel as though you are going to tip over then as suddenly as it starts it will stop till you turn in the opposite direction then it does it again. Now I have found the cause of this although I can't currently fix it ? I tracked it down to the rear wheels I made by respoking my 20" trailer wheels into 16" rims.
The wheels are either slack enough to turn freely and clunk up and down or tight enough to not clunk up and down and the wheel barely turns.
When over tight each wheel randomly emits a clunk and you feel a slight lurch.
Seems the trailer wheels who's hubs are good quality alloy and sealed bearings were made some time ago and are IMPERIAL 1/2" sat on a M12 bolt - would you credit it. So until I have built a new axle with 1/2" stub axles I will have to live with this.
Transmission parts location is not great as big pulley could interfere with right knee however it worked flawlessly and the chain stayed exactly where it needed to be - so that is a big + for my design
It also has a turning circle close to the Python , the only fly in the ointment is the swing of the pedals will have to be allowed for.
So plenty to think about and plenty to improve , it is an unpleasant white knuckle ride at the moment and I have not see it's potential yet.
Paul
because:-
a) I am looking for sympathy
b) I am looking for help
c) I am currently stumped
problems discovered so far are in at least 1 of the above categories [ and some are probably in several ! ]
I have ridden it briefly the same 280 meters the pedal car has traveled , although in all honesty the pedal car has done that trip more than once and is no where near as frightening as this contraption !!!
these problems are in no particular order:-
1) can't get all the low gears [ this has consequences [ see below ] - puzzling I cannot find the Low and High gear stops ! on the rear mech- it maybe because the mech is now rotated 90 ' and points horizontally instead of vertically ? not researched that yet
2) because I cannot get into the low gears whilst I have the power to cycle away from a stand still the torque steer takes you by surprise and send you veering all over the road. It almost feels like a MBB and it certainly shouldn't
3) the steering like the other bike I had with 16" front wheel is very quick - so you only need a small turn of the handle bars for a large steering input - this again takes you by surprise and with the next problem makes progress down the road in a straight line almost impossible [ at the moment ]
4) i think it is following the camber so when you come off the crown of the road it veers very quickly into the kerb - I have experienced this in the UK upright ' big wheel ' delta trikes most unnerving till you have mastered it.
5) I said to Nanny this morning it is tilting about 2 - 3 inches in either direction measured at the seat top - this is bad as you feel as though you are going to tip over then as suddenly as it starts it will stop till you turn in the opposite direction then it does it again. Now I have found the cause of this although I can't currently fix it ? I tracked it down to the rear wheels I made by respoking my 20" trailer wheels into 16" rims.
The wheels are either slack enough to turn freely and clunk up and down or tight enough to not clunk up and down and the wheel barely turns.
When over tight each wheel randomly emits a clunk and you feel a slight lurch.
Seems the trailer wheels who's hubs are good quality alloy and sealed bearings were made some time ago and are IMPERIAL 1/2" sat on a M12 bolt - would you credit it. So until I have built a new axle with 1/2" stub axles I will have to live with this.
Transmission parts location is not great as big pulley could interfere with right knee however it worked flawlessly and the chain stayed exactly where it needed to be - so that is a big + for my design
It also has a turning circle close to the Python , the only fly in the ointment is the swing of the pedals will have to be allowed for.
So plenty to think about and plenty to improve , it is an unpleasant white knuckle ride at the moment and I have not see it's potential yet.
Paul
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So I have added another set of drop outs to the new fork , they are behind the originals this I am hoping will have 3 affects ?
1) increase the trail to decrease urge to run down camber
2) improve chain line to reduce torque steer
3) improve chain line [ by moving cassette rearwards ] to stop chain hitting fork in high gear
Left side and right side , wonder if rear mech will still work ? [ just like having a built in hanger extender ?
and improvement to chain line.
Like the rest of the fork welding almost finished however needs testing before I weld it up fully.
Paul
1) increase the trail to decrease urge to run down camber
2) improve chain line to reduce torque steer
3) improve chain line [ by moving cassette rearwards ] to stop chain hitting fork in high gear
Left side and right side , wonder if rear mech will still work ? [ just like having a built in hanger extender ?
and improvement to chain line.
Like the rest of the fork welding almost finished however needs testing before I weld it up fully.
Paul
So the advice is get rid of as much of the trail as possible , down to about 1" if possible !
So we have the main frame to the right a wooden spacer @ the frame wheel interface [ approx 1/2" [ 12mm]] the head tube is now @ 85'
This does result in 1" of trail , however.....
The gap is 4" , yes so I can add some steel and fill it no problem however :-
That in theory means my legs have to be 4" longer
AND
It adds 4" of tiller , I HATE tiller !!!
Now my usual yard stick for inseam is 29.5" between seat front and BB axle [ although this differs slightly depending on seat back angle.]
I the picture it actually measures 32" at present so I am not looking for the whole 4" but 2.5"
Now the BB is movable towards the seat , this will probably result in undesirable soft collision between my heal/foot and the front wheel.
Racing that would be no problem , in an urban environment it is more problematic , the Yellow Nazca I borrowed suffered from this and a couple of times at extreme limits of the turning I got my heal the wrong side of the wheel so I could not straighten it up.
On a trike that is really just AGAIN ! however on the 2 wheeler you of course went over.
Of course the seat could also move forward maybe 1.5" , however how close would you put the crown jewels to that upright frame ?
Paul
So we have the main frame to the right a wooden spacer @ the frame wheel interface [ approx 1/2" [ 12mm]] the head tube is now @ 85'
This does result in 1" of trail , however.....
The gap is 4" , yes so I can add some steel and fill it no problem however :-
That in theory means my legs have to be 4" longer
AND
It adds 4" of tiller , I HATE tiller !!!
Now my usual yard stick for inseam is 29.5" between seat front and BB axle [ although this differs slightly depending on seat back angle.]
I the picture it actually measures 32" at present so I am not looking for the whole 4" but 2.5"
Now the BB is movable towards the seat , this will probably result in undesirable soft collision between my heal/foot and the front wheel.
Racing that would be no problem , in an urban environment it is more problematic , the Yellow Nazca I borrowed suffered from this and a couple of times at extreme limits of the turning I got my heal the wrong side of the wheel so I could not straighten it up.
On a trike that is really just AGAIN ! however on the 2 wheeler you of course went over.
Of course the seat could also move forward maybe 1.5" , however how close would you put the crown jewels to that upright frame ?
Paul
Decided instead of bodging the 2 stubs together [ which could be fast , just ugly and lots of welding ] I would cut them out and add a single piece:-
So the front of the new piece is tacked to the steering tube and it is being marked up for cutting and then welding to the upright of the rear part.
I have actually now welded most of the joints and filled in some of the tacks , not quite straight however that is my fault for using 3 different tubing sizes.
DON'T DO THIS YOURSELF !!!
It is a world of unnecessary pain , I did it because I wanted to ape a ' commercial trike ' where the BB slides inside the boom for leg adjustment.
Waste of time and effort just make it all out of the same square tube size , much easier and accurate to jig up and in all honesty the welds look less messy.
Not out of the woods yet.
Needs some assembly and the all important test ride....
Paul
So the front of the new piece is tacked to the steering tube and it is being marked up for cutting and then welding to the upright of the rear part.
I have actually now welded most of the joints and filled in some of the tacks , not quite straight however that is my fault for using 3 different tubing sizes.
DON'T DO THIS YOURSELF !!!
It is a world of unnecessary pain , I did it because I wanted to ape a ' commercial trike ' where the BB slides inside the boom for leg adjustment.
Waste of time and effort just make it all out of the same square tube size , much easier and accurate to jig up and in all honesty the welds look less messy.
Not out of the woods yet.
Needs some assembly and the all important test ride....
Paul
That is a very good article, overall, & that chart might be marvelous, but strangely low resolution pixelated most of the text too severely to read after enlargement, so I abandoned saving the desirable article. Thanks, though. Perhaps time will be found later to investigate it & rescue it from WordPress.
Bravo, Bucko. Others cheer your efforts on both sides of the Atlantic. Is your insistence on those tiny wheels entirely to improve aerodynamics & lower center of gravity? My commercial ReBike lwb recumbent ride, speed, & comfort are severely impaired by the 16" in front, though it does help drop the elevation. I have a LWB streamliner in-the-works (much of it inspired by things like this) that will use a 32" rear & 26" front, at least briefly, to destroy rolling resistance & greatly improve comfort, so I have great interest in how you're doing what you're doing with this project. Apologies on length... Your write-up, not mine.Decided instead of bodging the 2 stubs together [ which could be fast , just ugly and lots of welding ] I would cut them out and add a single piece:-
So the front of the new piece is tacked to the steering tube and it is being marked up for cutting and then welding to the upright of the rear part.
I have actually now welded most of the joints and filled in some of the tacks , not quite straight however that is my fault for using 3 different tubing sizes.
DON'T DO THIS YOURSELF !!!
It is a world of unnecessary pain , I did it because I wanted to ape a ' commercial trike ' where the BB slides inside the boom for leg adjustment.
Waste of time and effort just make it all out of the same square tube size , much easier and accurate to jig up and in all honesty the welds look less messy.
Not out of the woods yet.
Needs some assembly and the all important test ride....
Paul
Ronald
Nice to hear from you.
Whilst I will have to ' train ' in an urban environment this machine is designed with the race track in mind so there are compromises that would not be favoured for a leisure only machine.
i am very short on power so anything to reduce weight and reduce drag will help.
Those wheels could be as much as 0.5kg lighter than 20" wheels and there are 3.
Aiming for 15kg with no specialist materials ?
Drag should be reduced if they are less width than my shoulders , not sure how that will pan out.
gearing will be a problem want it to do maybe 18mph at normal cadence [ what ever that is ] and a flat track.
elevation is a compromise @ 4" hopefully enough if I treat it gently on urban routes for racing 3" could suffice ?
this is better table
Paul
Nice to hear from you.
Whilst I will have to ' train ' in an urban environment this machine is designed with the race track in mind so there are compromises that would not be favoured for a leisure only machine.
i am very short on power so anything to reduce weight and reduce drag will help.
Those wheels could be as much as 0.5kg lighter than 20" wheels and there are 3.
Aiming for 15kg with no specialist materials ?
Drag should be reduced if they are less width than my shoulders , not sure how that will pan out.
gearing will be a problem want it to do maybe 18mph at normal cadence [ what ever that is ] and a flat track.
elevation is a compromise @ 4" hopefully enough if I treat it gently on urban routes for racing 3" could suffice ?
this is better table
Paul
So do I fit ?
Well sort of , it is canted over to the left a bit , possible drop outs/fork hacking problem - not looked yet.
What is interesting is the axle is now asymmetrical so instead of a equal 24" track [ probably safe enough for testing ] it has only 18" track on the left side and 27" track on the right side [ to wide ]. I should have move my left foot down , it is inconclusive as the whether the left rear wheel sits in my body shadow [ aerodynamically ]
reduced front boom length to about zero and does look as though I could pedal this [ just ] wrong shoes suggest there may be an issue with right heal hitting either/both fork or rear mech. So onward sort of , packing for the 24hr pedal car race on 29th June and a ferry to Netherlands 1 July so time is sort of being used up at a phenomenal rate !
Paul
ps having Covid is not helping matters......
Well sort of , it is canted over to the left a bit , possible drop outs/fork hacking problem - not looked yet.
What is interesting is the axle is now asymmetrical so instead of a equal 24" track [ probably safe enough for testing ] it has only 18" track on the left side and 27" track on the right side [ to wide ]. I should have move my left foot down , it is inconclusive as the whether the left rear wheel sits in my body shadow [ aerodynamically ]
reduced front boom length to about zero and does look as though I could pedal this [ just ] wrong shoes suggest there may be an issue with right heal hitting either/both fork or rear mech. So onward sort of , packing for the 24hr pedal car race on 29th June and a ferry to Netherlands 1 July so time is sort of being used up at a phenomenal rate !
Paul
ps having Covid is not helping matters......
