Front brake!

[colin400four]

Hi Kent400,

Many Thanks for your Ideas / Tips.

COLIN

[K2-K6]

Well done, it's always nice when you get a pass and can get out on it legally.

As above Colin if you changed the pads then you could try the old ones if still serviceable to see if that's the origin.

Just a small point and probably not related to the noise, I've always set the static pad by rotating the wheel and adjusting the screw until you can just hear the pad touching the disc, not enough to slow the wheel but to wipe the surface. A common complaint with this era is poor response when wet, but if you get a slight rubbing they are more progressive in rain (should not generate heat when dry though when running and not used).

[colin400four]

Hi K2-K6,

Many Thanks for your points. 

COLIN.

[PatM]

Thanks for all your comments and support on this one and all points noted and compared.
I have actually stripped and re-built the caliper as suggested and to my amazement- it was fairly clean inside and upon removing the seal- no growth or material build-up that may have been causing stiction.
On assembly and bleeding- I used standard DOT 5- there was little difference with the new pads
I then changed back to the old driven pad and left the new fixed- and the wheel rotated with minimum interference and rubbing- the adjusted being backed off a good deal- I suppose I got some satisfaction that I could know see the assembly moving, upon application of the brake-leaver.
And it was in that state that it passed the MOT.

My younger bro has a mint 400/4 and he's had 5 to my knowledge- loves them since they came out.
In his experience this is all very familiar. He said that EBC pads seem to be slightly more generous in thickness and in his recollection it took a good few hundred miles before the EBC pads worked properly!

[florence]

I have always found EBC pads last forever but have no feel and do not slow the bike down noticeably.  I recently bought whatever are the pads that Dave Silver stocks, Vesrah I think, and they are excellent.  I did not realise pads could make so much difference, they have made it feel like a different bike. 

It is worth noting that it is worthwhile to strip and clean the caliper fairly regularly and, of course, replace the seal.  The winter is very harsh on the caliper.  Lets face it, the brakes on these bikes are terrible at the best of times.

[K2-K6]

Your'e right there Florence, they do need a regular clean to keep them operating as well as possible.

I don't think the caliper is that bad as an engineering solution, more that you can't get enough leverage with standard master cylinder. I call this effect the first real anti-lock disc brake system as you'd have to have hands like king Kong to lock the wheel in the dry!!

Ran a K2 750 with twin standard discs and std master in the 80's and they were suprisingly effective as the effort you have to put in was reduced for any friction that was generated.

[florence]

You are right, but I was very surprised how much difference the pads make.  I had put up with the brakes for years and accepted that they were just a bad design. I stripped and cleaned the caliper, used a new piston and seal and the Vesrah pads from David Silver and adjusted carefully.  The brakes are now the best they have been in 15 years

One day, as an experiment (with the old EBC pads in), I found a quiet long straight stretch of country road.  I placed a stick in the verge, went back down the road and approached my marker at 60mph making sure there were no cars following.  When I reached the stick I did an emergency stop to see how far I would travel.  I was surprised to see that the braking distance was not in any way as far as I had imagined it would be.  Evidently, the brakes have no 'feel' but are actually not as bad as one perceives them to be.

The best brakes I have experienced were the ones on my CX500, twin disc with twin piston calipers.  They were amazing, I could stop on a sixpence with those in the dry, from any speed.  If it could be done, without loosing the wire spoked wheels, I would love that set-up on my CB500.

[Yoshi823]

When I did the twin disc conversion on my commuter 550 it used a set of Ferodo sport pads on one disc & Vesrah in the other. As the Ferodo were good in the wet but the others were rubbish it was auto-select disc system. The standard master cylinder was utilised with careful bleeding of the system...& the front wheel was easy to lock up if I got heavy handed with it...like when I was speed zapped one morning on the way into work. 42 in a 30, but that was once he had a lock on me, so I was probably going faster.

[K2-K6]

As you say Yoshi, if you blead them well they are fine with a standard master cylinder and I guess that later ones with taller reservoir was to give more fluid "stock" between services. If you check the level regularly there is ample safety margin.

I'm making the assumption that operating two calipers with the same master then you would halve the hand effort to get the same amount of squeeze at the wheel?

I like brakes with a softer start point anyway as if they are too grabby at first they are harder to control over a range of grip levels, you just need them to keep on getting more power as pressure is applied in a linear fashion.

Yes Florence the pads have a major effect so worth evaluating if you are not happy with what you've got, and sticking to a good type when you find it.

Your point about the CX500 are interesting. Years ago rode a superdream 400 (same brakes I think) track bike and they'd used a girling master on std brakes which they found too sharp so had then fitted a device to add some squishyness? into the system to make them easier to control, they were still very potent though.

[PatM]

I had all sorts of brake issues with my CX500 but I have to admit most of it was due to corrosion and riding it in all weathers- but what a bike! Most people that took the piss out of it were either loaded or had never ridden one. They were all-season bikes, for sure. I miss CUC 500V!

[F2 Paul 876]

Yes PatM you are right about the CX they were a all season bike i rode it all year round .
The ones that took the piss had not ridden one, i found it the most comfortable bike i have had.
I dispatched on mine, did well over 130k on it before i was taken out on the west way and put it into the back of a petrol tanker it never hit the deck just well and truly stuck in the back of the tanker took 4 coppers to get it out  , me went to the Hammersmith Hospital it to a breakers  .
I would have one again if i could afford one after my 2 rebuilds.
Paul
My CX over the years

[PatM]

Paul

Ouch!- the joys of all-year round biking- I can recount some of those also- the best being when I dived under a Rover SD1 jumping a set of lights on my hack-of-a-A100 Suzi- only for the whole lot to burst into flames! Yep, recovery is slow process- skin-grafts take ages- and with a slimmer degree of certainty than restoring bikes.
I was waiting for my MOT last week and a couple of well-healed kids were debating what bike to get- R1, R6, etc- their education or parenting had done them proud- they certainly had some money by the sound of it. I engaged conversation, as the waiting for an MOT at Maidstone

[Yoshi823]

Sorry this is highjacking the thread but the George at Shoreham used to be a haunt of mine back in the late '70s. There used to be a crowd of guys who had CB400/4s who called themselves the 'Bromley Racing Team' & would offer out anybody to race them up through the lanes to Badgers Mount roundabout & back again. But the pub had too many complaints about the hordes of bikes & had to ban bikers. I went back there a few years later, ordered a load of drinks, then put my leather jacket on. When they said we're not allowed to serve bikers we walked out ...& left the drinks on the bar unpaid.


The George used to be a good place to go to after the Mayday Run. We were too tired to cause any noise as the day was quite intense.


Them were the days.............

[florence]

Hooray for CXs.  Lots of people say rude things about them but anyone who has ridden one will know how great they were.  Although quite heavy, mine would go round corners incredibly well leaning right over until everything was scratching and sparking, it took some nerve but once I realised what amazing traction it had there was no stopping me.  It devoured miles and was very comfortable. I had koni shocks to stiffen the rear and I had upside-down honda k4 handlebars.  When the exhausts fell apart I used a pair of old BSA A10 silencers on home-made flexible exhaust (from a tractor) down tube; sounded fantastic.  I discovered that sliding the forks an inch up in the yolks speeded up the steering and made it feel less heavy at the front.  I also cut down the saddle to improve the riding position.  One needs to sit 'in' a bike like that, not perch on top.  As the headlight unit was so ugly I replaced it with two CB125S units bolted together which made the bike look rather like a frog.

There were two downsides however, it did not have a kickstart so winter starting was always a pain and not an easy bike to bump start (always park on a hill I say).  The second problem was the water pump, which always leaked.

[Yoshi823]

Knock...knock!



Who's there?



CX500!


An old joke, but one that I remember well. Several friends had CXs & they had numerous problems...big ends being the main one. Then generators. Then cam chain tensioners. And as said, water pump leaks.


Glad that I bought a CB550/4.