Brake Pads

[sirch345]

Chris,

Ian,

It's indeed no surprise that the rear is less effective than the front; single (ie. 1 pair of opposed) pistons, only 1 disc, smaller disc at that. But even then, I was surprised how feeble it felt.

Good point on the pads, I hadn't thought of that. Changing pad material is the easiest upgrade. I don't want to lock the back wheel. I'm buying new GG pads for the front (one disc has oil / brake fluid on it), so I may as well get the complete set. I read up on the difference between GG & HH pads, found this: https://www.wemoto.com/info/brake_pads_ ... ck%20brake.

So in any case, GG's for the rear. The bike won't be seeing a racetrack whilst in my (not very capable) hands, so GG's all round looks good.

Now making a paddock stand. Being from Yorkshire, I wasn't going to buy one. The first fun came with those black swingarm end caps. Seeing 6 holes, I thought, special pin spanner, they'll unscrew - easy turning & indexing job. A bit of looking on Ebay showed a pic of the back of the caps - they just snap in. Why the $%*& do Honda then make it look as if they unscrew?

Anyway, I had a lump of 2" diameter steel bar laying in the dust, so the extensions are machined up now, I have a length of M8 threaded rod (largest size that'll fit through the hole in the pivot pin), just need to fab up some bits of 1" box section. Tomorrow's job.

Ian

Ian,

Interesting to read what Wemoto say about the different grades of brake pads

A good job you had not fabricated a special pin spanner before realising the swingarm caps are push on
Goodness knows why they were made to look that way.

On upgrading the rear caiper, I found this: https://www.ebay.co.uk/itm/265248000339 ... SwbhthBL6-

A piston that fits a whole range of rear calipers, from CBR900, CB600F, CB1300 and the VTR1000. It would seem they all share a common rear caliper.

As you said Chris, the rear caliper only has one piston (not an opposed pair as I'd wrongly assumed). To accommodate pad wear, the caliper floats. I might be wrong, but I think that a single piston floating caliper arrangement gives exactly the same braking force as would a fixed caliper with two opposed pistons. I don't think that adding an opposing piston increases the clamping force on the disc. All that having opposing pistons does is it lets the caliper and disc be solidly mounted.

Is this correct? If so, then the solution to more rear braking would be:
- A larger diameter disc
- Higher pressure (reduce the MC diameter of change the pedal leverage ratio)
- A caliper with a larger diameter piston (1 or 2, makes no difference I think)
- Twin pistons, like the front brakes
- Heavier boots!

It'd be great to hear from anyone who has uprated the rear brake. It seems that 1993 - 1997 CBR1000's went the twin (or maybe triple) piston route: https://www.boonstraparts.com/en/part/h ... 0000070243

Ian

I think I may need the later, heavier boots

Have a look at this link, changing the master cylinder for a different size piston doesn't always give a better brake, it can just feel like it. I realise that is the front brakes they are talking about, but may apply to the rear as well :
viewtopic.php?p=123361#p123361

I see Tony has come back with the information on a better rear brake caliper and master cylinder, although not sure which model and bike it would be from

Chris.

[sirch345]

Have you checked to see what type of pads you have? I ask that because I have found with a set of HH pads, the rear brake is very easy to lock up. For this reason I run GG pads in the rear. They do act a bit like you have described, in that you do tend to need a bit more pressure on the brake lever to get them working and are a bit difficult to actually lock up the rear wheel.

Thanks for the tip Mike

Chris.

[sirch345]

The rear can lock up if you downshift aggressively downshift, so the amount of braking force from the rear that you need us less than you might think.
But it's easy enough to fit a Brembo caliper and MC if you want better rear braking.

Tony, can you remember which bike and model a Brembo rear brake caliper and master cylinder would need to come from

Chris.

[IanB]

Thanks all,

Yes, I have noticed the engine braking when changing down. I guess that's why slipper clutches are made: https://www.motoracingshop.com/en/tss-s ... 97-03.html

More than I want to spend, but handy to know they're available.

Chris, I know what you mean by reducing the MC diameter. Reading the article on diameters etc, "feel" comes into the equation. How you quantify this, I don't know - what are the units of feel? Ringtwitches/Km? Dunno. What does seem to be the case is that a harder brake handle / pedal "feels" like a more powerful brake than a soft one, whereas the opposite is the case (assuming properly bled etc).

One possibility to get more pressure on the rear caliper would be to extend the brake pedal - it means a complete new footrest / MC mount, longer pedal, quite a bit of work, but there is room - it'll just clear the swingarm.

Apart from changing the pads, I'll put this one on the back burner for now I think - first get the front end done, paddock stand first, then top yoke / fork seals / taper rollers & front caliper seals.

Ian

[Jamoi]

Hi Ian,

You might be surprised by the variation in braking power between the different brake pad materials and manufacturers, I was!

I installed new sintered "performance" pads in the rear caliper on my VTR (a long time ago) because I was used to just shopping for the strongest braking pad material I could find. But, I found I locked up the rear wheel too easily and I lacked the finesse required to manage that along with all the other skills when riding progressively.

So I then Swapped them out for good quality organic pads, which gave me just the right amount of bite (a lot more pressure on the lever required) for my riding style and ability.

In your case it could be as simple as changing the pads for more bite, service the caliper, fluid and maybe put a braided line on.

Just a thought, before you get tempted to engineer a 4 caliper setup

[IanB]

Thanks Jamoi,

I confess to knowing nothing about the effect of different pads! I don't know what's in there at the moment, I haven't looked. The bike has done 20k Km since new, and it has never been thrashed as far as I can see - no footpeg or right hand header scuffs, never dropped. So my guess would be that it has factory original pads. Do pads change with time? These would then be 22 years old.

I was looking at EBC GG pads all round - these things: https://www.ebay.co.uk/itm/334084633446 ... SwqVlg~4-s The advert says they're "organic", whatever that means. Probably made from thinly sliced baby otter or something. On GG or HH, I saw in an online review that HH pads can be "scary" when wet; that's not a word that I like to see in the same sentence as "brakes", so GG look fine.

It would be great if a simple pad change would do it - I have enough other projects to mess with. I'll do that first.

Cheers,

Ian

[sirch345]

Thanks all,

Yes, I have noticed the engine braking when changing down. I guess that's why slipper clutches are made: https://www.motoracingshop.com/en/tss-s ... 97-03.html

More than I want to spend, but handy to know they're available.

Chris, I know what you mean by reducing the MC diameter. Reading the article on diameters etc, "feel" comes into the equation. How you quantify this, I don't know - what are the units of feel? Ringtwitches/Km? Dunno. What does seem to be the case is that a harder brake handle / pedal "feels" like a more powerful brake than a soft one, whereas the opposite is the case (assuming properly bled etc).

One possibility to get more pressure on the rear caliper would be to extend the brake pedal - it means a complete new footrest / MC mount, longer pedal, quite a bit of work, but there is room - it'll just clear the swingarm.

Apart from changing the pads, I'll put this one on the back burner for now I think - first get the front end done, paddock stand first, then top yoke / fork seals / taper rollers & front caliper seals.

Ian

Ian,

A very good question that "How you quantify this" and one I'm not even going to attempt to answer
At least you have your head around what can happen with swapping brake calipers, M/Cylinder or both which is the main thing.

A longer rear brake pedal should make a difference I'm sure

Chris.

[gilson]

Thanks all,

Yes, I have noticed the engine braking when changing down. I guess that's why slipper clutches are made: https://www.motoracingshop.com/en/tss-s ... 97-03.html

More than I want to spend, but handy to know they're available.

Chris, I know what you mean by reducing the MC diameter. Reading the article on diameters etc, "feel" comes into the equation. How you quantify this, I don't know - what are the units of feel? Ringtwitches/Km? Dunno. What does seem to be the case is that a harder brake handle / pedal "feels" like a more powerful brake than a soft one, whereas the opposite is the case (assuming properly bled etc).

One possibility to get more pressure on the rear caliper would be to extend the brake pedal - it means a complete new footrest / MC mount, longer pedal, quite a bit of work, but there is room - it'll just clear the swingarm.

Apart from changing the pads, I'll put this one on the back burner for now I think - first get the front end done, paddock stand first, then top yoke / fork seals / taper rollers & front caliper seals.

Ian

Ian,

A very good question that "How you quantify this" and one I'm not even going to attempt to answer
At least you have your head around what can happen with swapping brake calipers, M/Cylinder or both which is the main thing.

A longer rear brake pedal should make a difference I'm sure

Chris.

All this talk of the rear brake made me think. It's related so hopefully not a thread hijack. On my track bike I'm now considering cutting my rear brake lever off. I never use it, it's already slightly broken from an off and it would be easier than removing it and all the gubbins.

Actually, could I remove all the rear brake, including the caliper, MC and disc to save weight or is this a really stupid idea?

[8541Hawk]

All this talk of the rear brake made me think. It's related so hopefully not a thread hijack. On my track bike I'm now considering cutting my rear brake lever off. I never use it, it's already slightly broken from an off and it would be easier than removing it and all the gubbins.

Actually, could I remove all the rear brake, including the caliper, MC and disc to save weight or is this a really stupid idea?

This whole thread has me a bit confused. I wonder if the OP is riding the bike like a cruiser with the weight biased to the rear. On this bike, IMHO, like most sport bikes tend to have a more even weight bias. So as soon as you apply the brakes, the weight goes forward and any aggressive rear brake application, be it from hard application, bigger rotors or aggressive pads will only cause the rear wheel to lock up as there is no weight on it.

As for your question on a track bike, well that is one of the few places that I actually us the rear brake. Comes in handy to settle the chassis at time or the advanced use of using it to tighten up a line in a corner. I did write a post on the topic, I believe it was "Rear brake, why is it there" to give a bit more detail on my thoughts on the topic.

And the last bit, I saw a comment that HH rated pads don't work well in the wet. I believe this is false info as I have ridden in downpours with my Vesrah HH pads with no issues at all

[tony.mon]

Agree, Hawk.
To answer the question about which Brembo setup fits, none as far as I know as a straight swap, but it's easy to fabricate an underslung bracket for whatever good quality caliper you get.

Equally, you can easily make up a mounting plate for the MC.

[IanB]

Hi Hawk,

No, not really riding it like a cruiser - the bike's still new to me and it still has the stock clip-ons (these are coming off soon). I was just trying to get to know the bike. I tried pulling the clutch in at about 60Km/h, then applied the rear brake - see what it does. My feeling was, it didn't do very much, that's all. Previous bikes I owned had far more effective rear brakes.

You're right about weight transfer to the front under hard braking - the extreme of this being stoppies, with the back wheel off the ground. But I was always taught to use both brakes, not just the front. Isn't this stil good practise? There was even (and this goes back decades) a Moto Guzzi with linked brakes; the brake foot pedal worked the rear brake and one front disc, the front brake handle operated the other front disc.

So - I'm just trying to get a more balanced front/rear braking for riding under normal conditions. Emergency stops are always going to be with most weight on the front, but hopefully there won't be too many of those.

Ian

[gilson]

All this talk of the rear brake made me think. It's related so hopefully not a thread hijack. On my track bike I'm now considering cutting my rear brake lever off. I never use it, it's already slightly broken from an off and it would be easier than removing it and all the gubbins.

Actually, could I remove all the rear brake, including the caliper, MC and disc to save weight or is this a really stupid idea?

This whole thread has me a bit confused. I wonder if the OP is riding the bike like a cruiser with the weight biased to the rear. On this bike, IMHO, like most sport bikes tend to have a more even weight bias. So as soon as you apply the brakes, the weight goes forward and any aggressive rear brake application, be it from hard application, bigger rotors or aggressive pads will only cause the rear wheel to lock up as there is no weight on it.

As for your question on a track bike, well that is one of the few places that I actually us the rear brake. Comes in handy to settle the chassis at time or the advanced use of using it to tighten up a line in a corner. I did write a post on the topic, I believe it was "Rear brake, why is it there" to give a bit more detail on my thoughts on the topic.

And the last bit, I saw a comment that HH rated pads don't work well in the wet. I believe this is false info as I have ridden in downpours with my Vesrah HH pads with no issues at all

Cheers Hawk, this post?

https://r.tapatalk.com/shareLink/topic? ... source=app

[8541Hawk]

It's the next one down .......viewtopic.php?f=7&t=28968

[8541Hawk]

Hi Hawk,

No, not really riding it like a cruiser - the bike's still new to me and it still has the stock clip-ons (these are coming off soon). I was just trying to get to know the bike. I tried pulling the clutch in at about 60Km/h, then applied the rear brake - see what it does. My feeling was, it didn't do very much, that's all. Previous bikes I owned had far more effective rear brakes.

You're right about weight transfer to the front under hard braking - the extreme of this being stoppies, with the back wheel off the ground. But I was always taught to use both brakes, not just the front. Isn't this stil good practise? There was even (and this goes back decades) a Moto Guzzi with linked brakes; the brake foot pedal worked the rear brake and one front disc, the front brake handle operated the other front disc.

So - I'm just trying to get a more balanced front/rear braking for riding under normal conditions. Emergency stops are always going to be with most weight on the front, but hopefully there won't be too many of those.

Ian

I meant no offense, just trying to understand where you are coming from. Yes a few bikes over the year came with linked brakes. It was also one of the first things to be changed for performance use.....on my Guzzi's it was the first thing I changed. Now the thread I linked to in the last post gives my thoughts on rear brake application. But to be honest, on the street you could remove my rear brake system and I wouldn't even notice 90% of the time.

[gilson]

It's the next one down .......viewtopic.php?f=7&t=28968

A very interesting read. Thank you