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Discussion Starter · #1 ·
How do you know if you need a new break pad or need to bleed the hydraulic fluid for your front break?
All i know is my break is getting weak to the point its a safety concern- this is an area i have 0 experience in and to my knowledge these are the two components that dictate your front break power.


Thanks fellas.
 

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I totally rebuilt my front brake with a new piston, seal kit, master cylinder kit, and one of the last OEM brake reservoirs that Honda had. The one area that I cheapest out on and am now kicking my behind is I did not switch the hose. The old hose will flex and you will lose some feel with that. If you are going to rebuild I suggest going to a braided line for improved feel. That being said, the front brakes in these bikes are not the greatest at their best. Squeeze the lever. If it goes to the bars then you have air in your lines. They will need to be bled. Make sure you check the fluid level to make sure it is not low. The brake pads have wear indicators. For how cheap they are and how old those pads are, it's almost worth it to just replace them regardless.
 

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Discussion Starter · #3 · (Edited)
When i squeeze the lever it stops clear of the bar, but when im in the move i have to squeeze quite hard to stop. Theres a lot of steep hills in my area and to stay still on an incline my foot is more effective than the front break.
 

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You've got a serious safety concern going on here, but fortunately not difficult to fix. The front brake in good condition should have no difficulty stopping the wheel from turning. First off; how do you feel about working on your brakes yourself? Is this something you feel comfortable doing? If not, get it to a professional bike mechanic familiar with your Honda, if I remember correctly yours has a parking brake on the gear lever which is slightly different from the normal Honda rear brakes....
If you are up for a little spannering, find the factory service manual for your bike, and read the section on the front brake. Also look at the parts list for your bike. You have the Automatic 400 right? Single disc rotor? You have a floating calliper which may have seized on the pins and causing your problems. CMSNL.com have exploded diagrams for your brake online an I suggest you start there to have a look and study the components before you do anything.
Your bike is at least 30 years old, so: Next, find a supply for a master cylinder rebuild kit, brake pads and shims, Dot 4/5 brake fluid (enough to fill the whole system twice.) the brake hose, you might want to consider getting a braided stainless hose as the rubber hose on your bike will be swelling by now if it hasn't been replaced in 30 yrs!; and the oil bolt washers. It's probably a good idea to replace the piston seal too! And the "O" rings for the pad pins.
If you can find all these and you're good to tear down the brake system, take a moment to photograph where your hose runs through the handlebars and round the headstock and down to the calliper.
Brake fluid is Hygroscopic, meaning it attracts water and will degrade over time, it is also very good at paint stripping, wear eye protection and remove the gas tank and put it away safely before you drain the hose, and do not reuse old brake fluid. It's cheap enough.
Read the brake section of the FSM again.
Good luck, and post again how you got on.
Nigel.
 

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One assumes that you are using both brakes in concert.

I bled my front brake in like five minutes by myself, and it looked like it hadn't had any fluid in it for years. If there is any doubt at all, just do it - it's easy. I got paranoid and didn't pull the lever all the way to the bar (used my finger for a stop, lol). And I NEVER "pump" brakes when bleeding (why disturb an air bubble and turn it into lots of little ones?)... With your Honda, place container (or put hose on bleeder valve if you wish to be neat), break the bleeder valve loose (don't loosen it, just get it so you can easily do so with one hand), pull lever, open bleeder and quickly close before you run out of lever pull / pressure. Rinse/lather/repeat. Make sure you have plenty of fluid in the MC to begin with and keep your eye on it during the bleeding (refill if necessary).

Having to squeeze your lever with lots of force might mean that your caliper piston is tight (corrosion?). Does it ever seem like it doesn't want to completely release when you let go of the lever?

Is your brake fluid still clear, or has it gone dark? It is hygroscopic (absorbs water) and the water content can cause issues with corrosion. If it doesn't look good, bleed it until it does (IOW, until you have replaced all the old fluid with new).

Regards,
 

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Check with Michael Morse, at Vintage Brake, Welcome to Vintage Brake! if you want to put together a front brake that really works..
 

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Discussion Starter · #7 ·
One assumes that you are using both brakes in concert...

Having to squeeze your lever with lots of force might mean that your caliper piston is tight (corrosion?). Does it ever seem like it doesn't want to completely release when you let go of the lever?
Yes i use both breaks together. Just my area is all hills. Lots of inching up and down hills in traffic- both feet are needed on the ground to stay up, leaving all the breaking to the front.

When i release the lever it doesnt hesitate to return to its neutral position. When i pull its just like i half half the breaking power. When i pull the lever half way i should be getting 50% stopping power and im getting 25%. When i pull all the way in it feels like i have 70% stopping power. and the bikes weight on a hill with just the front break is enough for the bike to 'skip' down the hill, a battle between my hand strength and what feels the break loosing grip. I cope by standing up to loosen the load and trying to hold the bike in place with my arms.


...pull lever, open bleeder and quickly close before you run out of lever pull / pressure.
Thats where i get a bit confused. When i pull the lever and fluid is released- im expecting the lever to go weak/start to feel loose. Is that what you mean by loose pressure?

Thanks for the break down of the how-to. I wont pump the break either thats a good point.
 

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my area is all hills.
Yeah, I remember riding some sort of contraption up a hill when I was there 25 or 30 years ago with Mom. Like a cable car? IDK.

both feet are needed on the ground to stay up
???

?????

Anyway...

the bikes weight on a hill with just the front break is enough for the bike to 'skip' down the hill
That doesn't seem right.

Thats where i get a bit confused. When i pull the lever and fluid is released- im expecting the lever to go weak/start to feel loose. Is that what you mean by loose pressure?
You pull the lever (and hold it) BEFORE opening the bleeder valve. When you open the valve, you've just released the pressure from your hydraulic system. If you don't (almost) immediately close the valve again, a little brake fluid (and/or air) will spurt out, then you'll not see anything because there is no more pressure (and your lever would be against whatever you placed between it and the hand grip or the handgrip if you don't use any spacer).

It won't kill you if you open the valve and don't get it closed fast enough. Well... Not unless you then say, "Job is done," and go for a ride :lol: . I'd just consider it to be a [/FAIL] and start over. You want the fluid (or fluid/air mixture) to still be coming out of the bleeder when you close it back up. And don't let off the lever when the bleeder is open - I don't KNOW that it'll suck air back through the bleeder, but I suspect that's what would happen.

Use a bleeder wrench or at least something that grips the bleeder correctly so it doesn't round off (or snap).

I am guessing that your caliper piston isn't wanting to move, but IDK. I'm no expert.

You'll know if you did it wrong because your lever will be mushy. In that case, no worries, try again. It'd be difficult to ruin something (unless you mangle the bleeder with your wrench). Remember that brake fluid loves paint though (it loves it like I love Pizza Rolls).

Regards,
 

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First the level of braking applied is not controlled by the distance the lever moves but rather by the amount of pressure applied. Once the "slop" is taken up there should be very little movement in the lever. What there is will be caused by either air in the line or flexing of the line itself.

What you describe are classic symptoms of worn/glazed brake pads which is normal with wear and also with age but could also be from the caliper not "floating" in which case you're only actually pressing one pad against the disc instead of both. I always recommend replacing both the front pads and the rear shoes on any vintage bike not only due to the wear issue but also because the glue that holds them together deteriorates with age. If you really want a bad day try being there when they come apart.
 

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...preferably as a bystander, well away from the roadway, lol.

Regards,
 
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