Front brakes tadpole trike

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Use your right hand and the right brake ?
 
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I think something is not right in the braking assessment. IF the front brakes are applied at speed, the trike will do a rear wheelie.
I myself am building a trike for a lady with MS and only going to use low gear thus no real speed. This trike has three wheels based on a standard 26 up-wrong bike but using 20 inch wheels for ease of getting on and off.
Yes all three wheels will have one brake lever. My take on three wheel braking is similar to a car with a trailer. Trailer brakes are applied first. If front brakes stop first the rear of trike could fishtail or swap ends
Think of it this way, your traveling 30mph front brakes apply thus the front starts to stop BUT the rear end is still going 30mph.
IMO three brakes on one lever is ok





'
 
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Use your right hand and the right brake ?
Isn't that the ultimately unbalanced front braking system? If split fore and aft any braking done by one hand is still balanced. I think in reality though that we don't go fast enough or brake hard enough for unbalanced systems to be critical. I certainly don't remember crashing on my only left / right trike because of unbalance braking.
 
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Isn't that the ultimately unbalanced front braking system? If split fore and aft any braking done by one hand is still balanced. I think in reality though that we don't go fast enough or brake hard enough for unbalanced systems to be critical. I certainly don't remember crashing on my only left / right trike because of unbalance braking.
Ok we are getting no where here so this is my last take on this .

Over 90% of commercial tadpole trikes ONLY have 2 front brakes , if the steering is designed correctly there is no brake steer so applying 1 front brake will still stop the trike safely just in twice the distance ?
 
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For what it is worth, and looking at it from a sudden stop perspective when you need brakes the most .....

A rear brake on a tadpole is pretty useless except for a parking brake or slowing down, neither of which is a panic stop. When starting my first casual trike explorations, I only had a rear brake and easily dragged the back wheel at walking speed down a steep grade - on bitumen. The grade was part of an official riding trail but quite steep for a short distance that ended in a narrow gateway and a sharp turn. Not the sort of place that you nee "iffy" brakes. I was ready for it and was only going slowly. I couldn't see behind and it was a few seconds before I realised what the jerking motion and noise meant. I eventually disconnected the rear brake and modified the front end to use individual disc brakes as it was easiest and I didn't know how long the trike interest would remain. End of problem and the rear was later modified for use as a parking brake. Great idea!

The problem with individual front brakes comes to the fore when using one arm for indicating. Not a problem if doing it casually. However, try it when going down a hill where you must be applying the brake at the same time or you will overshoot. You can mitigate the problem by applying steering pressure in the appropriate direction but that doesn't feel too safe. Going slower will mostly fix that but having electronic indicators activated by a quick flick of a switch is better and they stay on until you turn them off.

Panic tadpole stops will unload the rear wheel and is dependent on front/rear weight distribution. The harder you try to stop, the less effect the rear brake will have.

Having said all that, I plan to experiment with a double pull some time.
 
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I now plan to go with ONLY front brakes. My cable doubler didn't work out so going the KISS method.
I already have a brak lever that controls two cables.
 
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Im really learning something here :)
Ref popshots answer with regard to buying tried and tested plans... (just had a quick shufty at that hellbemt cycles link btw and have downloaded for digestion a bit later)...
What im finding is by having to figure out problems and asking questions on here to enable me to solve said problems, im learning what causes said problems in the first place which is giving me a more einstein (if you cant explain it simply you dont understand it well enough) view on the trike... So i can understand it at a fundamental level, and that i find more valuable than simply learning parrot fashion..
Im a builder by trade (read multi trader) with 30 years experience and this was after i did half an apprenticeship at BAe systems before i got bored standing by a bench with a file and windy drill...
If i teach someone something, i teach em WHY theyre doing it that way, not just HOW...
This then gives em the fundemental knowledge required to approach a different problem and solve it using the fundamental knowledge theyre now in possession of (which makes my job easier in the end)..
So thankyou all for all this, it really helps and in the end ill come out of it knowing how to design and build a trike as opposed to knowing how to put one together... Its the difference between a mechanic and a fitter if you get what i mean..
 
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Im really learning something here :)
i did half an apprenticeship at BAe systems before i got bored standing by a bench with a file and windy drill...
So thankyou all for all this, it really helps and in the end ill come out of it knowing how to design and build a trike as opposed to knowing how to put one together... Its the difference between a mechanic and a fitter if you get what i mean..
that would imply you are in the UK ?

The bicycle laws do state you need two independent braking systems , although there are silly things about seat height and small wheels that allow some of the stuff through loop holes meant for kids bikes.
Those independent systems can be on the same wheel.
So a 1 lever 2 cable on it's own could be construed as against the law in UK ?
This obviously has insurance implications , remember the guy in London they took to the cleaners [ prison IIRC ] for having only 1 front braked and fixed rear wheel ?
 
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The bicycle laws do state you need two independent braking systems
Thats not true

http://www.legislation.gov.uk/uksi/1983/1176/pdfs/uksi_19831176_en.pdf

Chapter 7a says, "every pedal cycle shall be equipped with at lest one braking system"

7bi says that if you have a fixi you need 1 brakes but 7bii says ordinary bikes need 2 brakes

but for any bike or trike with a max seat hight of 635mm only one brake will do.

If I understand english legal text correctly.

But tell that to the Police if you get caught.

I only have one brake and so far so good.
 
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going to still have a separate leaver actuated brake on the rear wheel. Maybe as a parking brake.
 
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cheers paul, will the rear and front not qualify as two independengt systems?
Hey I'm no legal eagle , I suspect we are looking at single points of failure in an independent system ?

So 1 lever , 2 cables . 2 brakes [ as you envisage ] on your trike is only 1 system as if the lever fails then the brakes fail ?

So 1 lever , 2 cables , 2 brakes and 1 lever , 1 cable and 1 brake on your trike is 2 systems ?

Which ever brakes you chose to connect to which lever ?
 
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Thats not true
Maybe ? ;):rolleyes:

Chapter 7a says, "every pedal cycle shall be equipped with at lest one braking system"
So this covers child's bikes some of which are sold with only a back pedal brake.

7bi says that if you have a fixi you need 1 brakes but 7bii says ordinary bikes need 2 brakes
A fixi is a brake [ if you are strong enough ]

but for any bike or trike with a max seat hight of 635mm only one brake will do.
Again trying to legislate differently for child's bikes to adult bikes , so instead of saying bikes for say 10 year old's or 15 year old's they tried to stipulate seat height etc without realising recumbent's can have very low seats.

In the eyes of the UK law these are both child's bikes ?





But tell that to the Police if you get caught.

I only have one brake and so far so good.
Luckily the average copper on the beat has little idea of Bicycle laws , also being on a delta trike it looks like a wheel chair and so they are very conscious of the fact you could be disabled - use this knowledge to your advantage !

In Mansfield there is a one way street I use a lot [ the wrong way of course ] it is short and if the law is not visible I usually ride up it on the road [ don't do this at home children ! ] once there were 2 special constables walking up the wide pavement so I mounted the kerb and rode up the pavement , when I caught up with then they separated and let me ride between them , there is no sign say you can ride this pavement !
 
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Hey I'm no legal eagle , I suspect we are looking at single points of failure in an independent system ?

So 1 lever , 2 cables . 2 brakes [ as you envisage ] on your trike is only 1 system as if the lever fails then the brakes fail ?

So 1 lever , 2 cables , 2 brakes and 1 lever , 1 cable and 1 brake on your trike is 2 systems ?

Which ever brakes you chose to connect to which lever ?
2 levers, one doing two front wheels(twin cables), one doing rear wheel...
not got em on yet, spent the day sorting the front end angles out and blowing holes in thin tube :rolleyes:
tomorrow gonna sort the seat back out, see what cables ive got and see if i can get the front brakes on and a tube guide under the trike because its rubbing on the chassis at the minute and spounds like a right bag of spanners..
 
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I assume it's the chain that's catching for the spanners sound. Tube guide is fine for the return as there's no tension on the chain. Don't use it for the power side of the chain though as you'll wear it out very quickly. For the power side you need a pulley or two. You'll also need to fabricate something close to the pulley to prevent the chain falling out of it.

Blowing holes is something we've all experienced. What welder are you using?
 
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I assume it's the chain that's catching for the spanners sound. Tube guide is fine for the return as there's no tension on the chain. Don't use it for the power side of the chain though as you'll wear it out very quickly. For the power side you need a pulley or two. You'll also need to fabricate something close to the pulley to prevent the chain falling out of it.(y)

Blowing holes is something we've all experienced. What welder are you using?
Yeh its rubbing underneath... Front derailleur not set proper either or could also be a 2 chainwheel version rrying to run 3 cogs... Not even sure i got the right rear derailleur either cos i swapped out for 9 cogs cos it had a disc brake but all can be sorted..
Chain tube? Needs to be lined up front and rear with chain angle... I can bend 22mm copper.. Or even 20mm plastic overflow... But which or what else??
Got a trick bmx rear wheel sprocket with a 13mm 1/4" drive socket acting as a bush under seat.. Works a treat, better now i cut about 10 links out of chain which is about 2 1/2 standard mountain bike chains in total..

Bought a lil tig, ive got a stick and a mig but the mig for all its murex and 180amp welds like dogshit but its prolly needing a new liner, new rollers and the gas stays on when you let go of trigger and tbh i could have turned it down and done a much better job with it had it been bang on but i like learning new stuff..
tigging is harrrrrrd man.... really gotta think about set up, doable tacking up with one hand but only just and you gotta set your machine up just right.... its cost me a fortune in argon already :rolleyes:

so yeh, did what you said, forgot to take a remodel pic of the new castor angle but its between 6-12 degrees, centre point as you said, new tie rod arm (used two gas struts and a bit of the tube to connect em) new track arms (strung it up properly to rear hub with chain on so it dont catch)..

ackerman now works, you can see it work, doesnt scrub, feels a lot more solid (if thats right word?) (positive maybe) but yeh, turns well, rides... ish (sortable though its just friction and seat position)

Not done seat back yet but gonna play with that tomorrow and have a pop (if i got enough cables) at front brakes (but still gotta make and fix disc brake calliper mounts)...

and chain tube?? not sure really?

you bang in with those recomendations with the front geometry, i made a couple of lil vids but cant upload em here, difference is night and day though (y)
 
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Chain tube? Needs to be lined up front and rear with chain angle... I can bend 22mm copper.. Or even 20mm plastic overflow... But which or what else??
Usually in the UK it is easiest to get that black tubing sold at garden centres for irrigation ?

It comes in a coil so unwind about 6 ft and either hang it in the sun with weights on the bottom , or hang it full of boiling water or both , it will straighten.

As such a long chain actually has a drop due to it's weight you won't really be able to match that in the tubing , so just arrange to fix it loosely at each end and let the chain move it where it want's in i.e when it changes ring/sprocket in the middle you may need a third mount for some ' sag ' control.

Fixing could be either a length of bicycle chain which depending on orientation can control swing but allow front to back movement , or just use cable ties.
You want black ones as the white degrade under UV light.

Make sure you get a positive clamp at the front or rear to stop creep down the chain else the rear mech will try and eat it [ don't ask how I know this ]
Best thing to do is make two hole at one or both ends in line with the chain say 2" apart and run one cable tie through them , then suspend that cable tie with another one ot two ?

Getting closer...
 
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Usually in the UK it is easiest to get that black tubing sold at garden centres for irrigation ?

It comes in a coil so unwind about 6 ft and either hang it in the sun with weights on the bottom , or hang it full of boiling water or both , it will straighten.

As such a long chain actually has a drop due to it's weight you won't really be able to match that in the tubing , so just arrange to fix it loosely at each end and let the chain move it where it want's in i.e when it changes ring/sprocket in the middle you may need a third mount for some ' sag ' control.

Fixing could be either a length of bicycle chain which depending on orientation can control swing but allow front to back movement , or just use cable ties.
You want black ones as the white degrade under UV light.

Make sure you get a positive clamp at the front or rear to stop creep down the chain else the rear mech will try and eat it [ don't ask how I know this ]
Best thing to do is make two hole at one or both ends in line with the chain say 2" apart and run one cable tie through them , then suspend that cable tie with another one ot two ?

Getting closer...
Cheers Paul, whats creep though?
I'm sure ive got some old tube of some description kicking about somewhere that will do until it goes to paint...
Just had a vision of using part of an old rear deraileur, Im sure i saw something similar somewhere.. maybe take the spring out but leave the suspension arm in place so it can move side to side freely? Still... more friction i suppose...
Gonna get back up there and have a bit of a fettle (y) (hopefully wont run out of gas... again :rolleyes:)
 
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