Re: Honda PCX (150) Linked Brakes
Posted: Fri Sep 16, 2016 10:30 pm
Thank you everyone (almost) for the interest and replies. One or two of you force me to repeat for the 3rd time that the reason for this post was not to complain, nor am I seeking help. I have stated in both my post & subsequent reply that I wished to inform other users and hopefully save them from a nasty accident due to not knowing the facts of the poor rear brake performance.
Sadly gn2 your reply was that of an idiot who did not correctly read my post nor do you understand the subject of it. (Quote: Set up properly the CBS system on the PCX works just fine.Taking the CBS system to bits then complaining the braking system doesn't work... really?) As I have just stated the existence of serious problem, stated that I am a mechanic previously (therefore not without knowledge) & have indicated that a average rider would not normally discover this except under bad circumstances or traction conditions & below state a little more about myself, maybe there is just a chance I know something that you do not and risked sharing that knowledge with others for their safeties sake. And just maybe the CBS (S = system so Centralized Braking System system is redundant.) is not as "properly" setup as you might imagine and it is not the 1st time I have pointed out to motoring dealerships and mechanical workshops that something they have done is actually wrong, faulty or defective.
The left lever operates a primary cable just over 1 foot long (30 cm for the metric inclined) This connects to a compound T bar which on one end activates the secondary brake cable to the rear brake and activates a 2nd master cylinder mounted under all that covering on the steering shaft area. There are no adjustments to control bias front/rear. The only adjustment is a limiter in case of MC failure to cause some secondary cable function. I removed this master cylinder and fitted one long single cable. This 2nd MC does indeed operate the larger (26 mm?) piston of the caliper.
I would not have done this had it been ABS but it is not.(I also doubt I would have bought it had it had ABS but each to his own). I have done as Oyabun indicated and fitted a short braided hose and banjos linking all pistons. The small piston diameter difference is not a hindrance to safe braking any more so than 2 levers controlling 3 pistons. Funny how fitting a bigger disc or different caliper does not raise an eyebrow but separating a CBS system and you find harsh critics come out.
Having the front & rear brakes operate separately is exactly what people have had forever and still on many bikes do have. And if the brakes operation were truly balanced as with a car there would be no reason to have two controlling levers now would there.
pcx man (Quote: I stopped fast 2 days ago and the rear wheel on my 2013 PCX skidded. Also my parking brake holds great as long as the rear brake is adjusted correctly. You can not push it without skidding the rear tire.) Taking it on faith that my information might actually be correct, guess what wheel was doing most of the braking. Have you ever seen you tube videos of sports bikes somersaulting on emergency braking? I have not said the rear brake does absolutely nothing and as the front brake works really hard how much weight do you think was still on the rear tyre.(tire for Americans). Get it almost off the ground and sooner or later it must actually cease rotating in response to what little braking effort is being applied.
I was accelerating on about a 10 to 15 degree incline in rain once at about 20 kph and I got rear wheel spin for a few feet with a slight side slip. Does this mean my PCX is extraordinarily powerful or given the right conditions all sorts of things can happen? (the round smooth stones in the surface get very slippery when wet.) (An old surface type rarely used any more here.)
Mel46: since you do not have the brakes separated you would have to apply sufficient force to the rear wheel to replicate the condition I described of even walking beside the bike(maybe jogging). You might try running the engine against the brake a little. Not enough to heat nor harm the brake or strain anything. I too have tried the brake on the center stand by hand but not with the engine running. I am not certain if I could apply sufficient force to the wheel by hand to adequately test this way & have no one available to operate the brake lever while I might try. No point for me. Riding it proves all I need to.
kramnala58:(quote: Tampering with the brake system) as you put it. There is no law requiring CBS or ABS here. The brake hoses are certified. The cable duplicates the original made by Professionals. (No one here actually certifies cables but original manufacture has been replicated.) No other change or interference by me to the system.
chicaboo: (quote: I guess the drum is just useless for independent braking.) Not useless, but far below what I have experienced on any actual motorcycle with drum rear brake. If I had a decelerometer as I used to use in work experience tells me I get maybe 10% to 15% rear wheel brake effort. You tube videos of a Honda Ruckus also have people stating the standard drum brakes (fitted to both front & rear) are very poor for road use. Hence the modders fit disc brakes front and rear. My bigger worry is not for myself as now I know; but I am truly concerned for people riding with the CBS who have no idea how hard the front brake is working verses the rear wheel not working in corners under imperfect conditions who actually believe they are balancing their brake use.
Alibally: (quote: I can't understand why people muck about with braking systems. Fitting bigger discs and uprated pads I can understand but to tamper with a system that Honda probably spent a load of cash developing and works fine seems daft to me.) Your is the thinking of a person who does not think. You are fine with this, but let a person not interfere with the actual original brakes but just separate the brakes so that they can control the balance of braking and you have a problem.
dasshreddar; (quote: try adjusting the rear drum) They are adjusted all you can thanks. There is a couple of factors limiting adjustment. Not enough and no rear brake effort.(Lever bottoms out against handlebar). Too much and you have to strain the left lever to actually start the engine. The correct adjustment area is actually very small. And in case I had not stated it clear enough previously I reach a point where further squeezing of the brake lever returns no additional braking effort; it just strains the parts for no good reason. Looking from the outside I would have expected much greater braking effort from them. The drum does not appear small given the wheel diameter. But only the Dealership has been in there not myself and it is still less than 1 year old so I expect things to be in good & working order inside.
Again however my original purpose for this post was to try to make people aware of the risk of over using the front brake whilst cornering, particularly in less favourable conditions. I am possibly the only person who has had a reason to discover a potential fault where people may think they have balanced braking but I know that if my scooter has no internal rear brake fault from manufacture then with the CBS intact they actually have almost no rear brake effort going on and just do not know it, as I did not know it. For those who like to pick on me for offering the information, try to remember I was trying to help others. For 20 years I had been employed to fault find and diagnose faults with vehicles, and to explain to mechanics and to dealerships where a fault existed and if possible how it migh be corrected. I am sorry that explaining my past makes it appear like big noting myself but one or two out there need to understand from what I have said I have done to my scooter and the pictures I have shown of my changes to it (all my own work) maybe I am not a complete idiot.
Thank you to every person who showed interest and/or were not derogatory to me, for trying to help others. Sorry also this reply is so long but a fair bit came up to answer.
Sadly gn2 your reply was that of an idiot who did not correctly read my post nor do you understand the subject of it. (Quote: Set up properly the CBS system on the PCX works just fine.Taking the CBS system to bits then complaining the braking system doesn't work... really?) As I have just stated the existence of serious problem, stated that I am a mechanic previously (therefore not without knowledge) & have indicated that a average rider would not normally discover this except under bad circumstances or traction conditions & below state a little more about myself, maybe there is just a chance I know something that you do not and risked sharing that knowledge with others for their safeties sake. And just maybe the CBS (S = system so Centralized Braking System system is redundant.) is not as "properly" setup as you might imagine and it is not the 1st time I have pointed out to motoring dealerships and mechanical workshops that something they have done is actually wrong, faulty or defective.
The left lever operates a primary cable just over 1 foot long (30 cm for the metric inclined) This connects to a compound T bar which on one end activates the secondary brake cable to the rear brake and activates a 2nd master cylinder mounted under all that covering on the steering shaft area. There are no adjustments to control bias front/rear. The only adjustment is a limiter in case of MC failure to cause some secondary cable function. I removed this master cylinder and fitted one long single cable. This 2nd MC does indeed operate the larger (26 mm?) piston of the caliper.
I would not have done this had it been ABS but it is not.(I also doubt I would have bought it had it had ABS but each to his own). I have done as Oyabun indicated and fitted a short braided hose and banjos linking all pistons. The small piston diameter difference is not a hindrance to safe braking any more so than 2 levers controlling 3 pistons. Funny how fitting a bigger disc or different caliper does not raise an eyebrow but separating a CBS system and you find harsh critics come out.
Having the front & rear brakes operate separately is exactly what people have had forever and still on many bikes do have. And if the brakes operation were truly balanced as with a car there would be no reason to have two controlling levers now would there.
pcx man (Quote: I stopped fast 2 days ago and the rear wheel on my 2013 PCX skidded. Also my parking brake holds great as long as the rear brake is adjusted correctly. You can not push it without skidding the rear tire.) Taking it on faith that my information might actually be correct, guess what wheel was doing most of the braking. Have you ever seen you tube videos of sports bikes somersaulting on emergency braking? I have not said the rear brake does absolutely nothing and as the front brake works really hard how much weight do you think was still on the rear tyre.(tire for Americans). Get it almost off the ground and sooner or later it must actually cease rotating in response to what little braking effort is being applied.
I was accelerating on about a 10 to 15 degree incline in rain once at about 20 kph and I got rear wheel spin for a few feet with a slight side slip. Does this mean my PCX is extraordinarily powerful or given the right conditions all sorts of things can happen? (the round smooth stones in the surface get very slippery when wet.) (An old surface type rarely used any more here.)
Mel46: since you do not have the brakes separated you would have to apply sufficient force to the rear wheel to replicate the condition I described of even walking beside the bike(maybe jogging). You might try running the engine against the brake a little. Not enough to heat nor harm the brake or strain anything. I too have tried the brake on the center stand by hand but not with the engine running. I am not certain if I could apply sufficient force to the wheel by hand to adequately test this way & have no one available to operate the brake lever while I might try. No point for me. Riding it proves all I need to.
kramnala58:(quote: Tampering with the brake system) as you put it. There is no law requiring CBS or ABS here. The brake hoses are certified. The cable duplicates the original made by Professionals. (No one here actually certifies cables but original manufacture has been replicated.) No other change or interference by me to the system.
chicaboo: (quote: I guess the drum is just useless for independent braking.) Not useless, but far below what I have experienced on any actual motorcycle with drum rear brake. If I had a decelerometer as I used to use in work experience tells me I get maybe 10% to 15% rear wheel brake effort. You tube videos of a Honda Ruckus also have people stating the standard drum brakes (fitted to both front & rear) are very poor for road use. Hence the modders fit disc brakes front and rear. My bigger worry is not for myself as now I know; but I am truly concerned for people riding with the CBS who have no idea how hard the front brake is working verses the rear wheel not working in corners under imperfect conditions who actually believe they are balancing their brake use.
Alibally: (quote: I can't understand why people muck about with braking systems. Fitting bigger discs and uprated pads I can understand but to tamper with a system that Honda probably spent a load of cash developing and works fine seems daft to me.) Your is the thinking of a person who does not think. You are fine with this, but let a person not interfere with the actual original brakes but just separate the brakes so that they can control the balance of braking and you have a problem.
dasshreddar; (quote: try adjusting the rear drum) They are adjusted all you can thanks. There is a couple of factors limiting adjustment. Not enough and no rear brake effort.(Lever bottoms out against handlebar). Too much and you have to strain the left lever to actually start the engine. The correct adjustment area is actually very small. And in case I had not stated it clear enough previously I reach a point where further squeezing of the brake lever returns no additional braking effort; it just strains the parts for no good reason. Looking from the outside I would have expected much greater braking effort from them. The drum does not appear small given the wheel diameter. But only the Dealership has been in there not myself and it is still less than 1 year old so I expect things to be in good & working order inside.
Again however my original purpose for this post was to try to make people aware of the risk of over using the front brake whilst cornering, particularly in less favourable conditions. I am possibly the only person who has had a reason to discover a potential fault where people may think they have balanced braking but I know that if my scooter has no internal rear brake fault from manufacture then with the CBS intact they actually have almost no rear brake effort going on and just do not know it, as I did not know it. For those who like to pick on me for offering the information, try to remember I was trying to help others. For 20 years I had been employed to fault find and diagnose faults with vehicles, and to explain to mechanics and to dealerships where a fault existed and if possible how it migh be corrected. I am sorry that explaining my past makes it appear like big noting myself but one or two out there need to understand from what I have said I have done to my scooter and the pictures I have shown of my changes to it (all my own work) maybe I am not a complete idiot.
Thank you to every person who showed interest and/or were not derogatory to me, for trying to help others. Sorry also this reply is so long but a fair bit came up to answer.