Ideas for changing my braking system on my scooter

OK, I’ve had it with how my brakes work on my scooter. For some reason my rear master cylinder activates my rear
and a pair of pistons for my front brakes, which have 4 pistons. My front master cylinder activates the top 2 pistons
and my rear master cylinder activates the bottom 2 pistons. I really want to change this so that my rear master
cylinder only activates my rear brake caliper and my front master cylinder only activates my front brake caliper.

Now, if I keep my stock calipers, I will have to modify how they both work. For my rear brake, I will have to make
a change to a part where it makes split in the line from the rear master brake cylinder to both the front and rear brake
caliper and make it only go to the rear brake caliper. Then I also have to be able to connect all 4 pistons of my front
brake caliper connect to my front master brake cylinder. Solving the rear brake line should be as easy as just putting
a normal screw through the part where it splits the rear and front brake lines. However, I’m not sure if I’ll need to
put an oil bolt in there instead.

As for my front brake caliper and getting all 4 pistons to work, I have 2 ideas how to do this. One is get an oil bolt
with 3 holes and get the brake line for my rear brake caliper that goes from the rear master brake cylinder to the part
that splits the line and get another brake line that comes from the split to my front brake caliper (so now I would have
2 of the same lines) and connect all 3 lines together with an oil bolt with 3 holes. That way I have 1 brake line
coming from my front master brake cylinder which leads down to the joint that would connect the 2 brake lines to my
front caliper all held together with that oil bolt with 3 holes. I’m thinking that between each brake line that’s held
together with the oil bolt, that I’d need a washer in-between each brake line and at each end of the bolt.

My other option would be to have 2 brake lines coming straight from the front master cylinder and the oil bolt that
holds them to the master cylinder has 2 holes instead. Now the only problem I have with this setup is that I’d have to
get a custom brake line for the 2nd set of pistons on the front brake caliper

So I guess my question is, which setup do you think is better and more reliable? Also, anyone know where I can buy
these oil bolts? If you are not sure what I mean by an oil bolt, let me explain. It’s a bolt that is hollowed out, and
somewhere in the thread of the bolt is a hole that is drilled through. Most oil bolts screws only have one hole drilled
through the thread, but some may have 2 or 3.

Now one question I can see coming is “Why don’t you get a new front brake caliper?” Well, I really do want to, but
since my scooter is a Grand Dink 250, I haven’t seen any after market calipers made for it. Also, I’m changing my
front disk rotor to a larger size, so it makes finding an after market caliper even harder. It also doesn’t help that I’m
trying to do this as cheaply as possible, it being summer and all and the money isn’t coming in as much as it should.
Not to mention that I’ll also have to buy a torque wrench (finally, YES!!) to put in the new front disk rotor and a
new front tire.

So ya, this question is out there for others who have more experience in working with brakes. Can’t say I’ve done
this before, but I’m not afraid to try…

If you guys want, I’ll take pictures of how I finally have set it up and post it for you.

[quote=“johnledoe”]OK, I’ve had it with how my brakes work on my scooter. For some reason my rear master cylinder activates my rear
and a pair of pistons for my front brakes, which have 4 pistons. My front master cylinder activates the top 2 pistons
and my rear master cylinder activates the bottom 2 pistons. I really want to change this so that my rear master
cylinder only activates my rear brake caliper and my front master cylinder only activates my front brake caliper.

Now, if I keep my stock calipers, I will have to modify how they both work. For my rear brake, I will have to make
a change to a part where it makes split in the line from the rear master brake cylinder to both the front and rear brake
caliper and make it only go to the rear brake caliper. Then I also have to be able to connect all 4 pistons of my front
brake caliper connect to my front master brake cylinder. Solving the rear brake line should be as easy as just putting
a normal screw through the part where it splits the rear and front brake lines. However, I’m not sure if I’ll need to
put an oil bolt in there instead.

As for my front brake caliper and getting all 4 pistons to work, I have 2 ideas how to do this. One is get an oil bolt
with 3 holes and get the brake line for my rear brake caliper that goes from the rear master brake cylinder to the part
that splits the line and get another brake line that comes from the split to my front brake caliper (so now I would have
2 of the same lines) and connect all 3 lines together with an oil bolt with 3 holes. That way I have 1 brake line
coming from my front master brake cylinder which leads down to the joint that would connect the 2 brake lines to my
front caliper all held together with that oil bolt with 3 holes. I’m thinking that between each brake line that’s held
together with the oil bolt, that I’d need a washer in-between each brake line and at each end of the bolt.

My other option would be to have 2 brake lines coming straight from the front master cylinder and the oil bolt that
holds them to the master cylinder has 2 holes instead. Now the only problem I have with this setup is that I’d have to
get a custom brake line for the 2nd set of pistons on the front brake caliper

So I guess my question is, which setup do you think is better and more reliable? Also, anyone know where I can buy
these oil bolts? If you are not sure what I mean by an oil bolt, let me explain. It’s a bolt that is hollowed out, and
somewhere in the thread of the bolt is a hole that is drilled through. Most oil bolts screws only have one hole drilled
through the thread, but some may have 2 or 3.

Now one question I can see coming is “Why don’t you get a new front brake caliper?” Well, I really do want to, but
since my scooter is a Grand Dink 250, I haven’t seen any after market calipers made for it. Also, I’m changing my
front disk rotor to a larger size, so it makes finding an after market caliper even harder. It also doesn’t help that I’m
trying to do this as cheaply as possible, it being summer and all and the money isn’t coming in as much as it should.
Not to mention that I’ll also have to buy a torque wrench (finally, YES!!) to put in the new front disk rotor and a
new front tire.

So ya, this question is out there for others who have more experience in working with brakes. Can’t say I’ve done
this before, but I’m not afraid to try…

If you guys want, I’ll take pictures of how I finally have set it up and post it for you.[/quote]

WTF are you talking about!!! My god that was a lot to read. Man there are plenty of aftermarket calipers and disks to fit your scooter. Whatever application you want you can find. Every scooter and motorcycle here in Taiwan makes an aftermarket disk and caliper with the adapter. Try a Frando caliper (Taiwanese made) with a bigger disk and a stainless steel brake line. That should be sufficient. If you want to take it to the next level you could always get an aftermarket front master cylinder but that would be total overkill for you. All you need to worry about is your front brakes. Don’t touch the rears. Inexperienced riders lover to try and make their rear brakes better, but in reality you only use about 20-30 percent of rear brakes anyway. Always focus on the fonts for street riding and use the fronts as much as possible. You just haven’t found the right shop. Man that was a lot to read. Yikes!

rk1951, I’m guessing you didn’t see when I said “Why don’t you get a new front brake caliper?”. Like I said, I have
a Grand Dink 250. Sure I can get any caliper out there, but can I mount it on my scooter? I’m sure I could, if I can
find one that MAKES A MOUNTING BRACKET FOR MY SCOOTER! As you can tell, I’m frustrated by the
lack of aftermarket parts for my scooter. Just so you know, I’ve e-mailed Frando and Max replied to me saying
that there isn’t. As he said, “The model Grand Dink 250 is not the popular tuning motorcycle in main market.”
I know it isn’t nice to quote a Taiwanese person’s English, as I’m grateful he replied to me, but I’m sure you get
the drift.

As for my rear brakes, I don’t like how they ALSO activate my front brakes as well. My rear brake line from
the rear master brake cylinder, actually from a splint in the line from the rear master brake cylinder, is also
linked to my front brakes. So you know, my front brake caliper has 2 brake lines that power it. Have you
ever had a ride with that? I’ll tell you first hand that it sucks! What do you do when you are braking hard
and have both hands griping the brakes hard and you feel the front tire locks? Release the front brake lever,
right? What if that’s not enough? Release the rear brake lever next? But you have to brake hard. Do you
know how hard it is to have the presence of mind to be able to release both and then apply them again not
so hard, but hard enough to handle how fast you need to slow down?

As for finding the right shop, your right, I haven’t found the right shop, so I do the work myself. Does the
shop you go to change your oil properly? Like not just remove the oil plug, but the oil filter plug too? I
have never seen a shop that does, and that just something super simple and easy to do, and very important!
I’m tired of going to shops that do half-assed jobs and don’t bother to do the job right. In my mind, there
are things you don’t do when fixing a vehicle, like don’t clean things that need to be cleaned, don’t make
things dirty that should be clean, and don’t use the air-powered impact driver on everything until it goes
click. These are things I see all the time when going to most scooter shops. God, I’d hate to see how
they’d change my front disk rotor, as I have to replace mine, just pull out the air impact driver and
braaaap-braaaap each bolt in one at a time.

Arrrg, sorry for the rant, as you can tell as I said before I’m frustrated. Maybe you have found a shop
that does care about the work they do, but I know I’m no where near the shop you like to go to. Besides,
I enjoy doing work on my scooter, it’s one of the things I have fun with being here in Taiwan. Also, I’m
lucky to have a friend that knows a lot about my scooter that I can talk to about how to fix it.

[quote=“johnledoe”]rk1951, I’m guessing you didn’t see when I said “Why don’t you get a new front brake caliper?”. Like I said, I have
a Grand Dink 250. Sure I can get any caliper out there, but can I mount it on my scooter? I’m sure I could, if I can
find one that MAKES A MOUNTING BRACKET FOR MY SCOOTER! As you can tell, I’m frustrated by the
lack of aftermarket parts for my scooter. Just so you know, I’ve e-mailed Frando and Max replied to me saying
that there isn’t. As he said, “The model Grand Dink 250 is not the popular tuning motorcycle in main market.”
I know it isn’t nice to quote a Taiwanese person’s English, as I’m grateful he replied to me, but I’m sure you get
the drift.

As for my rear brakes, I don’t like how they ALSO activate my front brakes as well. My rear brake line from
the rear master brake cylinder, actually from a splint in the line from the rear master brake cylinder, is also
linked to my front brakes. So you know, my front brake caliper has 2 brake lines that power it. Have you
ever had a ride with that? I’ll tell you first hand that it sucks! What do you do when you are braking hard
and have both hands griping the brakes hard and you feel the front tire locks? Release the front brake lever,
right? What if that’s not enough? Release the rear brake lever next? But you have to brake hard. Do you
know how hard it is to have the presence of mind to be able to release both and then apply them again not
so hard, but hard enough to handle how fast you need to slow down?

As for finding the right shop, your right, I haven’t found the right shop, so I do the work myself. Does the
shop you go to change your oil properly? Like not just remove the oil plug, but the oil filter plug too? I
have never seen a shop that does, and that just something super simple and easy to do, and very important!
I’m tired of going to shops that do half-assed jobs and don’t bother to do the job right. In my mind, there
are things you don’t do when fixing a vehicle, like don’t clean things that need to be cleaned, don’t make
things dirty that should be clean, and don’t use the air-powered impact driver on everything until it goes
click. These are things I see all the time when going to most scooter shops. God, I’d hate to see how
they’d change my front disk rotor, as I have to replace mine, just pull out the air impact driver and
braaaap-braaaap each bolt in one at a time.

Arrrg, sorry for the rant, as you can tell as I said before I’m frustrated. Maybe you have found a shop
that does care about the work they do, but I know I’m no where near the shop you like to go to. Besides,
I enjoy doing work on my scooter, it’s one of the things I have fun with being here in Taiwan. Also, I’m
lucky to have a friend that knows a lot about my scooter that I can talk to about how to fix it.[/quote]

I almost don’t believe that Frando doesn’t make a caliper bracket for your application, but if you say they don’t then I believe it. Years before performance braking parts got big here, guys were making custom brackets for their bikes. I still see bikes like NSR’s and RZR’s with custom brackets all the time. Good shops can still do this for you and probably still do for certain bikes for other customers. Where are you located? My CSRT shop in Yingge can easily make you a bracket for your front brakes. Also, I bet you could buy a different rear master cylinder that will just control your rear brakes. I have not heard of your rear brake setup before, but it sounds terrible. But I guarantee there is way to fix your problem. Just gotta find the right shop.

Where am I? I’m in Hsinchu, so I think I’m too far away to take it to the shop you like.\

As for the rear master cylinder being the problem, it isn’t. The brake line from the rear
master cylinder connects to a “junction box” that connects the brake line from the rear
master cylinder to the lines that go to the front and rear brake calipers. I’m thinking
that I will still have to use the “junction box” because I believe that the rear brake line
has a different connection to the “junction box” than the other 2 brake lines. At least
that how it looks in my shop manual for my scooter. This shouldn’t be a problem, as
I should be able to just put the right size bolt through where the front brake line goes
to disable and seal it from oil going out from that spot. However, I may not be able
to do it that way, as I don’t know for sure if brake oil goes through that spot to the rear
brake line. I think I’ll have to ask my friend to order in that “junction box” so I can
take a closer look at it to understand how it works better. If brake oil does go through
the oil bolt that connects the front brake line first, then goes to the rear brake line, I’m
thinking that I’ll have to get a custom oil bolt instead.

I don’t expertise at this either, but I know that some race bikes have a similar setup that guarantees that you do brake with both rear and front tyres. But most likely those perform this job in a more smart and complex way. My recommendation for you is to find another bike like yours but in good shape. Then, check how good or bad the brakes do their job. Then decide whether to use the original system or go for some after market and more simple solution. RK is right, I reckon. There should be many workshops where to get that part (even though it could take a while to get the part to the shop), or even to build it up (it’s just a piece of metal with some shape and 4 or 5 holes).

Uggg, I just learned today why changing my brake system in the ways I had imagined wouldn’t work.

What I had learned about is the master brake cylinder piston to brake caliper piston ratio, and how that
affects the way the brakes work. If your master brake cylinder piston is too big, it will be very hard to
apply the brakes, meaning it will hard to squeeze them. Then as you are squeezing them, there will be
a very, very small difference between light braking to full disk lock. This is obviously NOT very good.

Now, if the master brake piston is too small, it will be very easy to apply the brakes, meaning it will be
super easy to squeeze them. However, you may find that you have the brake lever squeezed all the way
to the handlebars, and your braking power is still not enough. This too is NOT good, as you may never
get the full braking power out of your calipers or you may even squish your fingers between your brake
lever and handlebars.

It’s a good thing I learned about this before I had bought any master brake cylinders and brake lines. I
was thinking of putting the Kymco Exciting 250 front and back master cylinders on my scooter. The
front master cylinder might have been OK for my front caliper, but I think the master cylinder piston
is too big. I know the rear master cylinder piston is too big from the Exciting 250, as the rear caliper
is bigger than my Grand Dink 250 rear caliper. Heck, if I kept the Grand Dink 250 master cylinder, it
too would be too big for my rear caliper if I disconnected the rear master cylinder from the front brake
caliper.

Looks like I’ll have to get an after market solution, which will be a hassle as I will need to get a custom
caliper bracket made for both the rear and front calipers. Also, it means spending a lot more money
than I had planned on. But it’s better to spend the money than get into a wreck from a hack job on your
brakes.

If you’re interested, here are 2 pages I saw that helped explain it to me…

customfighters.com/forums/sh … hp?t=56704
vintagebrake.com/mastercylinder.htm