Author Topic: Front brake  (Read 4232 times)

adrian58

  • Guest
Front brake
« on: June 17, 2013, 10:10:07 PM »
The brake on my K2 isn't very effective (massive understatement). I've adjusted it and bled it but still have no faith in it. Any thoughts ? Are there better pads available or am I missing something ?

Offline Waggles

  • SOHC Expert
  • Posts: 315
    • View Profile
Re: Front brake
« Reply #1 on: June 18, 2013, 07:26:17 AM »
They're all like that!  ;D No, seriously, firstly it depends on what you are comparing it to. When compared to a modern bike the brakes are, um, 'retardationally challenged'. There will be no way you will be doing two fingered 'stoppies' on these bikes, and in the wet you had better keep applying it well in advance and feathering it occasionally to clear the water.

All that said, if I grab a serious handful on my F1 in the dry she stops pretty quickly, 'Satisfactory' is about the best I can say, certainly a mile better than my old SLS front drummed Triumph 500 speed twin I used to own!

Most usual problem is a seized caliper carrier arm, this needs to be free to swivel or you will not get full brake power, braided brake hoses definitely help, apart from that you will then need to strip clean and renovate the master cylinder and caliper to ensure nothing else is seized ( or partially so )

Can't comment much on different pads as I am still on my first set, but am considering changing them due to the squeal rather than lack of power

If all that fails then consider uprating the brakes!

Offline UK Pete

  • SOHC Jedi
  • Posts: 2696
    • View Profile
Re: Front brake
« Reply #2 on: June 18, 2013, 08:58:32 PM »
De grease the disk with brake cleaner, make sure the caliper is moving freely, and give the pads a light sand just to take away the glaze
that should do the trick, but dont expect it to work well in the wet, in the dry it should be ok
Pete

750rideruk

  • Guest
Re: Front brake
« Reply #3 on: June 18, 2013, 10:25:26 PM »
You will get a much better performing brake particularly in the wet if you drill the discs. Its not for those who are into concours and I feel the brake is slightly better in the dry also.

Offline JamesH

  • SOHC Jedi
  • Posts: 2846
    • View Profile
Re: Front brake
« Reply #4 on: June 20, 2013, 07:38:30 PM »
Also worth overhauling the caliper - the seals are cheap and I've found the difference between a fully rebuilt caliper and one that's sat for a while to be huge.

Offline Bitsa (Ralph Wright - RIP)

  • SOHC Jedi
  • Posts: 2937
    • View Profile
Re: Front brake
« Reply #5 on: June 20, 2013, 08:23:02 PM »
Nowt on tele except silly motorbike show so heres my two penny worth.Yes the old single disc is not the best since sliced bread but it seems to me some of you guys ride these bikes like they are modern.Ask a pilot if he flys a spitfire aircraft likes its todays technology.Agree with Waggles yeh depends on what you match it with.Try the good old single leading shoe, crap, double leading shoe crap.
In 1969 out come the first disc brake like winning todays lottery compared with the crap that was available at that time.I remember riding a vincent 1000 scared the crap out of me when applying the front brake I waited for the chute that did not happen and prepared to bail out.So lets think about it stop knocking the old stuff and give these bikes the respect they deserve treat them with respect and they will bring you home safe and sound.Also I have found pattern stuff is in French MERDE(S   T).
Cheers
Bitsa
Long Live Best Bitter.Status Quo and Sohc Bikes and common sense which you can not teach

Offline Green1

  • SOHC Jedi
  • Posts: 2656
    • View Profile
Re: Front brake
« Reply #6 on: June 20, 2013, 10:55:33 PM »
Well put Bitsa
I,v never really found the brakes to be problem and I push my bike hard rain or shine.The only time I have had problems is when I use my Triumph afterwards and I stop short at junctions  ;D
Mick
Current bikes
Honda CB750k1 Valley Green Metallic
Honda CB750k1 Candy Gold
Honda CB550k Candy Jade Green
Honda CG125
Aprilia Pegaso 650
Moto guzzi 1200 sport
Kawasaki EX650R (Mine until dave pays for it)
Kawasaki ZXR400 J

Offline Lobo

  • Lobo
  • SOHC Master
  • Posts: 1568
  • Lobo
    • View Profile
    • Lobo
Re: Front brake
« Reply #7 on: July 22, 2013, 06:03:50 AM »
Anyone able to suggest how to introduce a bit moe 'sponginess' into my front brake? (K2). Know that sounds odd (& introducing air into the system not smart)... but after the 1" mechanical slop (at the handle) the pressure builds so quickly that you can barely pull any further. Bottom line, my fingers are at too much of a stretch to get full pressure... should / when I need that.

I have of course tried adjusting the caliper away from the disc more.... unsurprisingly nil effect.

Conversely, and despite a whole lotta bleeding, my 400F brake lever comes almost back to the 'bar... the opposite bloody problem.

Cheers,
Lobo

Offline mick

  • SOHC Master
  • Posts: 1477
    • View Profile
Re: Front brake
« Reply #8 on: July 22, 2013, 07:51:12 AM »
Hi Lobo you could try using a dog leg brake lever, would help with your reach issues?  ;) cheers Mick.

Offline tom400f

  • SOHC Pro
  • Posts: 738
    • View Profile
Re: Front brake
« Reply #9 on: July 22, 2013, 08:32:43 AM »
@adrian58 I have a 400F and after reconditioning the master cylinder with new parts, cleaning the caliper, new seal etc and fitting EBC pads I find the brake to be perfectly adequate in the dry. I've also fitted Earls braided lines (though I know others on here say that's unnecessary). Not too interested in riding in the wet so can't say how good it is then.

@Lobo The bleed technique I used was one recommended here in the tips forum - to fill the system using a syringe attached to the bleed nipple. Worked a treat. Very firm and cannot pull the lever more than half way back.
1978 CB400F2 Yellow
1995 VFR750FS Red
1997 VFR750FV Lapis Blue
2013 Yamaha FZ8 Grey

Offline JamesH

  • SOHC Jedi
  • Posts: 2846
    • View Profile
Re: Front brake
« Reply #10 on: July 22, 2013, 08:36:01 AM »
Guess you could file down the lever where it contacts the master cylinder - so you have more initial movement in the lever before it starts to depress the master cylinder plunger. You would need to add additional material to the return stop side (or you could drill / tap and insert a set screw / lock nut to the same effect). You'd also need to ensure theres enough meat between where you remove material and the lever pivot pin hole. Just a thought.

Offline Lobo

  • Lobo
  • SOHC Master
  • Posts: 1568
  • Lobo
    • View Profile
    • Lobo
Re: Front brake
« Reply #11 on: July 22, 2013, 10:40:40 PM »
Thanks guys so far..

Like the tip (Tom) for reverse bleeding the system -makes a lot of sense for my 400F problem. Alas though, its the K2 that really needs attention, thanks James, - with respect I'll treat this suggestion as last ditch... really hoping of an easier answer! Perhaps I should add a little air after all!

Mick, good plan, but my K2 pretty much OEM & not wanting non-original parts.... if possible.

Cheers gents,
Simon

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal