Project Bike: Yamaha Jupiter-Z 2004, TDR Big Brake Disc Upgrade

Brake is always be the most important component of the vehicle. And for me it even more important than the engine, I assume that our safety often rely on this part, the condition of the brake system can determine our fate when driving or riding our vehicle.

That of course also applied to my 2004 Yamaha Jupiter-Z. It is more than 10 years ago since this model was launched by Yamaha Indonesia Motor Manufacturing.

It has air cooled single cylinder 110cc engine with carburetor fuel system and cdi ignition. This bike was so great, it never falls me to ground or break down when I was in the middle of travel to somewhere. Even I did not replacing much part to the newest one or a racing parts, it still under my control, I start it up, it light up, I open the throttle anyway anytime I want, it just accord my intention. 

 

Start from 2015, I began to make this bike as a refreshment project. Synchronize with my budget I begin to replace the crack rear combination lamp lens, replace the battery, suspensions, re-set the carb and the earlier activity, I replace and upgrade it’s piston and camshaft. But nowadays at my new living place (it’s 500km away from parents town) the braking system seems to tired and gave a little error symptoms. The engine feels heavier, it needs more effort to accelerate, plus I saw the disc brake surface is worn out and the braking pads have different thickness. This problem may caused by many things but I assume the old master piston membrane can make the caliper’s piston hard to release the pressure and the caliper itself is in dirty condition. 

(Courtesy of Yamaha Motor Manufacturing Indonesia)

Right after I go to Yamaha Indonesia website to check the parts catalogue and note the serial number. Well this is very helpful, the manufacturer gave the customers the valid data of the parts number and even the price and even it available in the app store or google play as an application! Wow! Imagine all the manufacturer give this service to us. Ok then, I order the piston set named master cylinder assy (5LM-F583T-00) to my relative at Yamaha Timuran Motor Solo and also the disc brake, I choose TDR big floating disc to upgrade my braking performance.

After a week the package arrived, I open it off and yes, my stuff are in good condition. I’m staring this large floating disc brake, this tdr brake maybe had about 330mm diameter, it’s 100mm or 10cm larger than it’s standard size. It have floating disc system, floating system is crucial in the big diameter brake kit, they dissipate heat faster than the rigid one, so the deformation caused by heat can be minimized. Yeah maybe it is not so effective applied in my bike but using this also accommodate my future project in case I upgrade the engine horsepower. It also equipped with the bracket, tdr gave a great manufacture on this part; seems like cnc machining with it’s aluminum material hmm… seems legit and precise.

Ok! It’s time to work. I decide to replace my piston cylinder first; open the brake bleeding port by loosen the screw shown at the picture above. And cock the brake handle until no brake flowing out from that port.

I think it’s better to collect the spill in the one place, because it have corrosive properties that can possibly damaging the paint.

Open the master cylinder cap screw, (again) be careful of this screw, this screw are rarely opened, once it open the head is vulnerable to damage if that happened… well it turns to rude way; we had to knock and smash the head until it’s open and sometimes it will leave scratch mark on the cap like you see what happened to mine.

Make sure that the brake fluid is already empty in the reservoir tank. If don’t, you need to pump the handle again till it drain or you’ll getting the spoil trouble when took out the piston.

Remove the brake handle by loosen the brake handle screw. Once the handle was removed you need to remove the circlip to take the piston out but you have to pull out the rubber cap first. Pull the piston out and yep, we’re ready to replace it with the new one.

Here it is the new brake master cylinder piston assy. Put it back to it’s master cylinder with the reverse step from the disassemble and of course; put the brake level back on.

Now we’re going to handle the wheel section;

  

Release the caliper screw and release the bracket screw. Oh, you need a special tools to release the bracket screw, it can’t be done by using the hexagon key or known allen key. You should use this;

I don’t know what it’s technically called but in my country this just called a “star key”, we need this T50 star key to open the bracket screw.

Don’t forget to clean the parts especially the bracket. We need to take attention at the brake shoe slide area; it needs to free from sludge and another dirt because it can resist the sliding of brake shoe, it can be jammed and of course it is not safety at all, so clean it up guys.

Now we prepare the installation of new disc brake to the wheel; first release all four disc brake shoe, replace with the new one and install the disc brake screw again. Please take attention to tighten the screw with cross direction, same as tighten the head cylinder screw, it will keep the tighten force even in all screw to the disc brake and prevent the bent of the disc.

 

Remember… that the disc brake bundle also contain it’s adapter. You can’t use the current caliper without the adaptor, it is lift the bracket so the caliper and it’s brake shoe can clamp the disc properly.

All you need is this hexagon cap M10 screw x 20mm length with head diameter 16mm. You need a pair of this to reposition the caliper.

Then install the new brake shoe first to the caliper bracket. The part number is 4US-W0045-00. 

Before you install the caliper to it’s bracket push the piston down with the locking pliers to ease attach it to bracket. After that tighten all the screw (include the brake bleeding screw) then pour the brake fluid into the master reservoir tank.

Cock the brake handle until it feels hard, it means the brake fluid started to fill into the braking system and also you should add the brake fluid if it reduce. If it is hard enough to push we can proceed to brake bleeding process;

Get the hose again and loosen the brake bleeding screw, then cock the brake handle until brake fluid fully came out from the bleeding port (please mind the brake fluid volume at the reservoir tank, don’t let it drain), if so add 2 or 3 cocking and hold with the full press position as the picture above shown, meanwhile tighten the bleeding screw. Repeat this particular step like 3 or 4 times then make sure that the brake handle had no excessive clearance, maybe around 5mm is enough, it will keep your brake performance work properly. Then install the master tank cap, clean your work station and you’re about to go.

Well it looks cool when you’re install the big brake disc to your bike, it is like you feel the racing aura, feel the satisfaction of upgrade, but despite of that you should keep your safety riding guys, because brake not guaranteed the safety, it is not to stop your bike it just slow down your bike.

Well thanks for comin guys, be safe and see you next time, ciao

Regards

Gigih P.