[python] Re: Rear brake
- From: Gideon Kahl <gideon.kahl@xxxxxxxxx>
- To: python@xxxxxxxxxxxxx
- Date: Thu, 1 Oct 2009 11:44:41 +0200
Leave out the brakes altogether - they just slow you down anyway :-)
2009/10/1 bepb <bepb@xxxxxx>
> Hi,
> I have been thinking a lot about the breaks for my python recently.
> I fixated the sockets for the front V-Brake yesterday but I am still
> hesitating with the rear break.
>
> I think, along the line of Sten, the rear break will bring more stability
> if used together with the front brake. On the other hand, considering a
> failure of the front break, I expect the rear break is very ineffective.
> I dont think you can expect 30% of the load on the rear weel while using
> the break on a python (Maybe on a upright). The center of gravity of a human
> is somewere in the hight of the stomach. With the hole legs alongside the
> front weel I guess you would have 70% of the weight on the front weel in
> normal operation.
>
> Some considerations:
> The rear but would create additional an additional downward force on the
> pivot. This will most probably enhance the rightening effect. For the front
> break I would expect a lessening of the rightening effect, most probably
> more pronounced, because the moment transfered from the weel to the front
> fork will lift the pivot. I would expect the lessening of the rightening
> effect of the front break would cause instability which could, at least to
> some extend, compensated by using it together with the rear break.
> Any comment from the experienced here?
>
>
>
> Best regards
> Gerald
>
>
> Dirk Bonné wrote:
>
>> Sten Albracht wrote:
>>
>>
>>> Just a small reply,
>>>
>>>
>>> On mine phyton I use the rear break a lot.
>>>
>>>
>>> Note that the rear brake has two functions:
>>>
>>>
>>> 1) Breaking as speed brake. But as you already noticed the
>>> amount of breaking capacities depends on the movement of front-rear
>>> axle-load during braking. The load on the rear wheel is often reduced
>>> coursing skids, Very theoretical story, but in common words we say
>>> front brake is used for 70% and rear is used for 30°
>>>
>>>
>>>
>> On my python I have skidded and fallen, because of the rear brake in
>> situations that were otherwise not extraordinary at all. A little flinch
>> on the brake lever is enough to fall.
>>
>> We have had this discussion on the list already and people suggested
>> making the braking power of the rear brake less, but I think this not a
>> good idea: On none of my bikes I use the rear brake. To me the function
>> of the rear brake is as a reserve when the front brake malfunctions
>> (e.g. cable break can be in a very nasty situation). And I do not need
>> the rear brake for additional stopping power. A reasonably well adjusted
>> front V-brake gives all stopping power I would need.
>>
>>
>>>
>>> Note as well that if there is enough braking force available to block
>>> the wheel in any condition, The wait of the bike (and driver +
>>> passenger) will not have any influence of the length needed to stop,
>>> as is very unknown to people! Meaning providing the bike with only a
>>> front break does not necessary means it will break slower! (but
>>> regarding the geometry of the phyton this might become a nice discussion)
>>>
>>>
>>> 2) Braking for stability, In this case we dose the rear break
>>> only to a minimum so peddling still is easy possible. But without
>>> peddling the bike comes to a premature stop. This kind of brake using,
>>> brings a lot of stability into the bike at (very)low speeds (2-5
>>> km/h). Things like turning on the road, small alleys and all other
>>> obstacles we find on the stupid Duth bycicle traks.
>>>
>>>
>>>
>> Ah okay, I can recognize that. When I make a 180 degree turn on very
>> narrow roads I use pedal pressure in combination with the _front_ brake.
>> I can make very short and very slow turns like that. At speed smaller
>> then the minimum "stable speed" (5-6km/h), it helps to use the brake to
>> give a contra to the pedal pressure, so it is possible to use a high
>> pedal pressure without actually speeding up. But I do use the front
>> brake, it works for me, no need for a rear brake.
>>
>> On a racing kayak you use a combination of paddle pressure contra a leg
>> pressure to keep from falling over (for those that do not know, most
>> racing kayaks are like bikes, they fall over when you do not
>> paddle/move). I find this gives a similar feeling as when braking and
>> pushing on the pedal simultaneously. Only slight adjustments in either
>> pressures (leg vs. paddle, or brake vs. pedal) are needed to keep a
>> balance.
>>
>>
>>>
>>> On the other hand there is lots to find about this braking technique
>>> on the internet, Its very common to handle motorbike at small speeds.
>>>
>>>
>>>
>> Never ridden a motorcycle, but I assume it must be similar.
>>
>>
>>>
>>> I advice you to build in a rear brake it’s a must-have.
>>>
>>>
>>>
>> Geef maar op: ik ben gewoon te koppig! :-D
>>
>> Dirk
>>
>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> S. Albracht.
>>>
>>> Engineer.
>>>
>>>
>>> DeMaCo Holland bv
>>> Oester 2
>>> Postbus 4
>>> NL 1723 ZG Noord Scharwoude
>>> tel: +31 (0)226 33 21 81 - Direct
>>> Fax: +31 (0)226 33 21 11
>>> E-mail: sa@xxxxxxxxx www.DeMaCo.nl
>>>
>>> <blocked::file:///C:/Documents%20and%20Settings/rve/Toepassingsgegevens/Microsoft/Handtekeningen/
>>> www.DeMaCo.nl>
>>>
>>> Chamber of Commerce: 37079728.
>>>
>>> _______________________________________________________________
>>>
>>> Disclaimer
>>>
>>> DeMaCo is not responsible for changes of the contents in this email and
>>>
>>> attached files due to sending and transportation. Neither can DeMaCo be
>>>
>>> held responsible for changes from your side. No legal consequences can be
>>>
>>> derived from the contents of the e-mail. The contents of this e-mail are
>>>
>>> exclusively intended for information purposes to the addressee. DeMaCo
>>>
>>> will accept no responsibility for any damage as a result of the use
>>> and/or
>>>
>>> acceptation of the contents of this e-mail.
>>>
>>> _______________________________________________________________
>>>
>>> Мы пошли в луну, но нашли землю
>>>
>>> * ***
>>>
>>>
>>>
>>>
>>
>> ============================================================
>>
>> This is the Python Mailinglist
>>
>> //www.freelists.org/list/python
>>
>> Listmaster: J�rgen Mages jmages@xxxxxx
>>
>> To unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx
>> with 'unsubscribe' in the subject field.
>>
>> ============================================================
>>
>>
>>
>
> ============================================================
>
> This is the Python Mailinglist
>
> //www.freelists.org/list/python
>
> Listmaster: Jürgen Mages jmages@xxxxxx
>
> To unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx
> with 'unsubscribe' in the subject field.
>
> ============================================================
>
>
Other related posts:
