rear drum not grabbing

What has been suggested before, remove the wheel and clean the brakepads and stuff. big chance your problem is there.

Is there no way to put the original brake lever back (the one with the knurled axle where the original footbrake chrome part slides onto) and go from there with an extension or something?

Converting to disk is (and exuse me for being rude and correct me if im wrong) looking at your skillset not really an option. I suggest making this work properly first. We both know its possible.
 
If it were me, I would concentrate on improving the front braking, modern pads, rotors etc., that's where most of the braking energy takes place.

Glad to hear you are sorting the rear brake out.
 
Bert Jan said:
Is there no way to put the original brake lever back (the one with the knurled axle where the original footbrake chrome part slides onto) and go from there with an extension or something?

Converting to disk is (and exuse me for being rude and correct me if im wrong) looking at your skillset not really an option. I suggest making this work properly first. We both know its possible.
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This was actually what I did in the very beginning. There are a few reasons I had to abandon the old lever, first because of the triangle frame suport there was no way to run a direct linkage, having to build an extender just to reach the stock lever, after I tried a few set ups I realized that the only way to link it changed the direction from pull to push (clearly BAD).

I agree that at this time a major swap to disc is out of my skill set but I would like to get there. This is not my first bike but most surely my first and not last project and I plan on learning what I can from it.
 
Rear drum (and front actually) work by way of a cam in the hub that pushes the shoes apart and into the surface of the drum. You can push or pull the lever, it doesn't matter. The cam will turn and push the shoes out.
 
VonYinzer said:
Rear drum (and front actually) work by way of a cam in the hub that pushes the shoes apart and into the surface of the drum. You can push or pull the lever, it doesn't matter. The cam will turn and push the shoes out.
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This is true but it caused the linkage to bend more than apply the brake when I tried it.
 
Because you're using the incorrect material for the linkage as someone pointed out earlier. Get some proper stainless rod and your problems will get a whole lot smaller, I bet.
 
I will check it out as a rod with less flex would work even with the arrangement as it sits now. I thought I had bought stainless but I have been wrong before. I do know that the outer tube is aluminium though.
 
If the outer tube is alu, your main material is too thin. Now, are you saying you use the rod to push the brake lever? You should only pull on such constructions. Pushing a rod needs a whole beefier system.
 
Bert Jan said:
If the outer tube is alu, your main material is too thin. Now, are you saying you use the rod to push the brake lever? You should only pull on such constructions. Pushing a rod needs a whole beefier system.
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It is not push motion at this time it is pull. I tried a push set up and I know that will not work with this rod.
 
I have been trying to source a stainless rod long enough but have not yet found one locally. I did come up with an idea that may work but I will have to mock it up to see. The brake at least helps in stopping now but I am still working on perfecting it.
 
My van failed emissions recently so I have been putting my efforts into trying to get it back on the road so it is sucking up my project time and funds.
 
Umusername said:
I have been trying to source a stainless rod long enough but have not yet found one locally. I did come up with an idea that may work but I will have to mock it up to see. The brake at least helps in stopping now but I am still working on perfecting it.
Click to expand...

These people are great for odds and ends when you're having to fab something... http://www.mcmaster.com/#
http://www.mcmaster.com/#threaded-precision-shafts/=nr706o
 
that lashup wil lnever work, anyway you try it, to much bump brake
i mean it has crazy bump brake
the ONLY way you can have a rear rod operated brake that actually works is to have the brake rod front pull be VERY close to the swinger pivot.period..... anyway else is a waste of time,it wont work worth dogshit, UNLESS you have a hardtail
a perfectly designed rod pulled rear brake sweeps right thru the centerline of the swinger spindle
many vintage mx bikes were like this,look at a maico or bultaco
the further away it is the more the rear wheel suspension travel will activate the brake,get it further than an inch or so away from the center and it turns to shit
OR go with a fully sheathed cable lashup
 
xb33bsa said:
that lashup wil lnever work, anyway you try it, to much bump brake
i mean it has crazy bump brake
the ONLY way you can have a rear rod operated brake that actually works is to have the brake rod front pull be VERY close to the swinger pivot.period..... anyway else is a waste of time,it wont work worth dogshit, UNLESS you have a hardtail
a perfectly designed rod pulled rear brake sweeps right thru the centerline of the swinger spindle
many vintage mx bikes were like this,look at a maico or bultaco
the further away it is the more the rear wheel suspension travel will activate the brake,get it further than an inch or so away from the center and it turns to shit
OR go with a fully sheathed cable lashup
Click to expand...

I plan on switching it very soon I will draw up my idea and post it in just a minute so you can see and make any comments on the idea that you have. Do you have any pictures of a good cable set up or a recommendation on how to do that? I have a coworker who worked in a bicycle shop for years and I have asked him about it before but I still need a little more clarification on how to make it work.
 
well just copy the cable principle and design as used on many vintage hondas cr125m/cr250m elsinores sl350 xl250/350 72-76 era they all had the excact same design and it works ok
you will need to have cable housing anchor at both ends
the front of the cable housing as one with the footpeg bracket the rear cable housing as one with the rear wheel travel
most time it is a boss on the brake backing plate
you will need a super beafy cable not like a bicycle or even front brake cable
i would just get one for a 72-75 xl250/350 and build around it
using that you are gonna have a cable with a pretty large arc to it but you wont find a real short heavy one anyway and short and straight with a sheathed cable will have travel issues anyway
as in the same TYPE of issue but different hahahaah

edit: if you want a grafic idea of the concept i spewed forth,just remove your shocks and swing your wheel up and down and watch the brake pedal go crazy
 
Ok so here is what I was trying to do. The colors are there to show where on the bike it would be for reference. The red rectangles represent two steal plates with the bottom purple line representing an axial pivot that will go through the triangle frame brace (one plate on each side) a top support and the linkages connected at the same point but on opposite plates (allowing an offset for the shocks an also providing linear travel). I hope this makes sense to someone other than myself. Thanks for the input I do appreciate this forum.
 

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Umusername said:
Ok so here is what I was trying to do. The colors are there to show where on the bike it would be for reference. The red rectangles represent two steal plates with the bottom purple line representing an axial pivot that will go through the triangle frame brace (one plate on each side) a top support and the linkages connected at the same point but on opposite plates (allowing an offset for the shocks an also providing linear travel). I hope this makes sense to someone other than myself. Thanks for the input I do appreciate this forum.
Click to expand...

very good !!! ferget all that about a sheathed cable this is much better anyway
remember, you need to have the long brake rod front pull location sweeping right over and thru the centerline of the swingarm pivot, looks like you have the concept?
and seeing as how you are at the beginning that will be easy to do
make it as perfect as possible for a solid feel with little or no bump-brake
allows you also to have an adjustable pedal up-stop because the suspension wont fuk with it
 
xb33bsa said:
well just copy the cable principle and design as used on many vintage hondas cr125m/cr250m elsinores sl350 xl250/350 72-76 era they all had the excact same design and it works ok
you will need to have cable housing anchor at both ends
the front of the cable housing as one with the footpeg bracket the rear cable housing as one with the rear wheel travel
most time it is a boss on the brake backing plate
you will need a super beafy cable not like a bicycle or even front brake cable
i would just get one for a 72-75 xl250/350 and build around it
using that you are gonna have a cable with a pretty large arc to it but you wont find a real short heavy one anyway and short and straight with a sheathed cable will have travel issues anyway
as in the same TYPE of issue but different hahahaah

edit: if you want a grafic idea of the concept i spewed forth,just remove your shocks and swing your wheel up and down and watch the brake pedal go crazy
Click to expand...
My coworker had actually recommended to me a brand of cable (that I don't recall at the moment) but apparently they were from the same company as cables used on Harley's and had the same part number and gage and well it was the same cable... What he said was they were selling them to bikers left and right because they could get the cabe for $2 sell it for $9 and the customer was happy because Harley wanted $52 for the same cable. I will just have to ask him again for the product information and I will gladly share it.
 
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