Quad Pedal Car - 2025 late Xmas/early Birthday present ?

So three inter-related problems to be solved :-
1) Seat position in relation to pedals.
2) Seat height.
3) Pulley position

front-right-side-view-DSCF9356.jpg

So this is the start position where we have both roughly placed using CF [ cellulose fibre ]
Now how does this meets the above conditions ?
1) measuring from the Python I know for this seat shape I need the front of the seat 29" from the BB centre , this is 28.5"
2) sadly the seat is much to high at 7" at the front lip.
3) probably not forward enough ?
under-seat-different-angle-DSCF9364.jpg

From this shot you can see the 3" spacer and the temporary floor/clearance gauge , so the seat is the height it is currently due to there being to much unused space in the pulley mount both above and below pulleys. Also it looks like the pulleys could be brought forward and higher up under the slope of the seat front. Although I suspect they will need to be as close to the seat as possible for only 2 pulleys to control both front and rear chain runs.
So that is Saturdays job to try that.

seat-from-behind-DSCF9362.jpg
The seat is now much closer to the rear meaning less steel to be used for a rigid seat mount.
At this point I am really really glad I built this tall work trolley , can you imagine trying to figure all this out with the car on the floor.

One other thing i had not though of ?
I now have 14" to much chain ! a weight saving me thinks :D (y)(y)(y)

Paul

ps nearly had a heart attack when going on the Pedal Car Racing results page and saw they had the first race as March 2nd ??? I had it down as April 6th ?
Seems March 2nd is the official cutoff for entry phew
So by then I should know whether it can race or not , even if at that point I still need to finesse the body work.
 
Could you make the seat framing from aluminum, and bolt it to the main frame ?
Might be a good weight saving, over welded steel :unsure:
 
So almost ready to try the chain ?
pulley-no-seat-DSCF9366.jpg

Looks neat enough , however floor is 3" from ground and pulley assembly 2.5" making the seat 5.5" from the ground.
To high !!!
pulleys-with-seat-DSCF9373.jpg
However all is not lost and now I can see there is acres of room in-front of the seat to enable the pulleys to be raised as only there bottom side needs to clear the seat mount as the chain passes under ?

pulleys-side-view-lines-DSCF9372.jpg
So blue will be a cross car seat mount then the red are 2 pulley supports welded to that mount and being bolted to the front of the seat .
Then the pulleys on a bracket will be welded to the red supports.
The hole assemble will then bolt to 2 pieces of angle with 5 bolt holes 1/2" apart [ adjustment ] welded to the car side rails as low as possible to maintain 3" ground clearance.

Paul
 
So tried the chain and I think it can work , the pulleys just not where I imagined them to be....

However we again butt up against the thorny problem of the chain keeper ?
pulleys-in-DSCF8324.jpg


This how I tackled it last time to make it so it could be removed without tools , is that necessary ?

I cut and shut a Q/R axle so it would fit , however that leaves a very big and chunky Q/R lever sat under the car at it's lowest point , possibly not a good idea.

Paul
 
Probably doesn't need to be QR - I mean, you do bring tools to a race, right ?
So, just a long bolt with a nyloc nut would work - And anyway, it looks like you could thread the chain, without even removing it.
I'm probably overlooking some vital factor, though, as usual :unsure:
 
undertoad


I suppose l am trying anticipate something that cannot be anticipated ?
Last year DannyC and I went to the Netherlands for 2 weeks , now in the past on these trips DannyC kindly provides the entertainment via breakdowns and mishaps etc etc .

However the last time my Python trike decided it would hog the limelight instead ?

So first off I had a catastrophic puncture on the front wheel , so I said to Dan I will try putting some air in it and see if we can limp to the boat terminal for the waterbus we were taking and deal with it at the first camp site ?
I pumped it as hard as I could and before I got the pump back in the pannier it was as flat as a pancake , the inner tube had split around the valve insert. Taking the front wheel off on a back street in Massluis is not for the faint hearted , only made being easier by there being 2 of us.

A few days latter it decided to drop the chain off the cassette on the 28T sprocket end , now this as happened only twice before once in the Netherland and once at home in many thousands of miles . To mitigate this I added one of those spoke protectors [ completely useless !!! ] all it did was divert the chain into the centre of the cassette and lock it up completely.
No amount of tugging or twisting could free it , so again the front wheel had to come out , we then had to split the chain and feed it through a small gap a link at a time [ tedious ].

So what could possibly go wrong with a pedal car and 2.5 times more chain than the Python ?

Answers on a postcard please to the usual address.

Paul

ps the second week Dan had a series of electrical/navigation and weather related problems , so the world was back to normal (y) :D
 
So what could possibly go wrong with a pedal car and 2.5 times more chain than the Python ?
No idea, only one chain-issue ever on a tadpole with 2 & 1/2 chains, and that was a chain snapped due to poor gearing and high loading and a weak link (Holland 2nd trip). But the overload was the 350W of Bafang power and you don't have 350W of Paul-Power to put on a chain. ;)
The worst problem last time out was the unexpected failure of the 20AH battery (I suspect it is just 1 failed cell), if it had not been for this we would have been fine. We survived. :)
 
No idea, only one chain-issue ever on a tadpole with 2 & 1/2 chains, and that was a chain snapped due to poor gearing and high loading and a weak link (Holland 2nd trip).
I could imagine the chain problems would be at either end ? more complicated stuff happens at the ends , seeing how we struggled/wrestled with Python chain I just wondered if it would be handy to be able to unhook it from the rollers in the middle ? I think part of the Python's problem was actually how short the chain was we seemed to have nothing to play with as it were ?

I suspect a tadpole is much easier to work on , this car could be a problem when fully encased as even with a removable bottom it is not easy to reach either the pedals or the rear cassette
;)
We survived. :)
So far we always have , and long may it continue I say .........
Remember my email 20% ferry fares if bought before March 3rd ?
Well ........

Paul
 
Front seat mount parts cut awaiting welding:-
seat-rail-mount-DSCF9378.jpg

So 2 right angled brackets with some adjustment to be welded to side frames , the piece across the car is I think 30mm x 10mm x 1.5mm it will have 2 M8 holes at the ends and 2 M6 holes nearer the middle for the seat.
new-seat-mount-DSCF9379.jpg

Pulley mount [ needs some trimming off bottom ] to slide under cross piece for welding.
pulley-mount-DSCF9380.jpg

Big circle pulley . hard line underneath bottom edge of chain , top dot drilled M8 lower one drilled M3 [ probably] for a Q/R skewer ?
Dotted line eventual trim line to open up the bottom.
tow-handhold-mount-DSCF9381.jpg


..and today's mystery item ?

To be welded horizontally to the ground at the rear of the car pointing backwards then the M10 bolt will be removed leaving a M10 hex coupler welded to the car ?

But why you ask ?

Paul
 
..and today's mystery item ?

To be welded horizontally to the ground at the rear of the car pointing backwards then the M10 bolt will be removed leaving a M10 hex coupler welded to the car ?

But why you ask ?
Possibly a fixing point for a trailer hitch of some kind? ;)
 
Post #94 has the answer , although a screw in flag mount is a good idea.

pulley-frame-DSCF9382.jpg


So this is where the under seat pulley action takes place , a 'R' clip holds the axle in and a Q/R when modified will hold the chain keeper should it need to be whipped out smartly to fix some problem or other.

pulley-frame-side-DSCF9383.jpg

Now I have drilled the holes it needs the bottom cutting off and nicely shaping to reduce it's height , then welding to this...

seat-mount-lower-DSCF9386.jpg


Lower seat mount , needs 2 x M8 bolt holes at the ends and 2 x M6 bolt holes for the seat , then the pulley mount can be welded in place.
MUST remember the pulley mount does not go in the centre.
left-seat-rail-mount-DSCF9387.jpg


Current seat adjustment an inch either way , if I need more it is just a matter of making a 3mm plate that fits between these parts with more holes in it.
If I find I want 1/2" of adjustment I can just weld a tab to the cross member and drill a M8 hole 1/2" away from the original.

So as many bases as possible covered.

Hopefully today can be a grind , drill and weld day and see this part fitted....

Paul
 
Well I did it !

lower-seat-mount-done-DSCF9393.jpg


Mount with M8 bolts to hold it and 2 x M6 bolts for seat fixing and pulley mount welded on.

pulleys-front-done-DSCF9391.jpg


Chain passing through from cranks see this view...

pulleys-back-done-DSCF9392.jpg


And exit here to reach the mech and cassette.

under-seat-done-DSCF9389.jpg


Clearance under seat.

seat-in-place-DSCF9388.jpg


So next up seat needs a upper rear mount , got the tubing just no idea how to do it , pictures of problem soon

Paul
 
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