Jump to content

5th gen and 6th gen braking systems


Epyon007

Recommended Posts

I've heard a few things and was wondering first off if anyone can confirm these things. 

 

First that when using the handle lever on a 6th gen you 5 of 6 pistons up front, not 4 of 6 like the 5th gen.

Second that the front pistons on the a 6th gen are bigger than a 5th gens.

 

If these items are actually true can you convert a 5th gen to be the same?  I rode a friends 6th gen and it sure seemed to brake better than my 5th gen.  If the first one is true I would think it would just be a matter of running plumbing differently, though I could see needing to change calipers potentially as well....

Link to comment
Share on other sites

Well after doing some picture research it appears that 6th gen calipers are definitely the thing that is responsible for the different distribution of braking force.  The first picture is claimed to be 5th gen fronts and the other are 6th gen.  The 5th gen calipers have 2 banjo bolts on them the 6th gen one doesn't.

honda-vfr800-fi-1998-1999-2000-2001-front.jpg

6thgen.jpg

Link to comment
Share on other sites

  • Member Contributer

For the most part what you stated is true, 5 front pistons on the 6 Gen and 4 on the 5 Gen but not 100% sure on the bigger pistons but sounds possible. There is another part to the 5 Gen that exist on the right fork though. The shop manual calls it a delay valve and not sure what it "delays" but it interconnects the two front calipers.

 

As far as replacing the 5 gen with the 6 Gen setup, based on what I can tell between the two it does seem feasible. Another unknown however is the rear PCV and whether it is identical, in both function and interconnectivity. Having both a 5 and 6 Gen and cannot say that one brakes truly better than the other but I also have both of mine setup near identically, both have the same pads (stock rotors) and stainless steel lines.

 

Although it could be the way I ride them, one as a commuter/tourer (6 Gen) and one as my sport/play bike (5 Gen), I do seem to like the way the 5 Gen operates and feels just a tad better. Maybe I need to do a scientific approach and ride both at "X" speed and do a braking comparison with using just the front brake, well front lever as the SMC will trigger regardless.

Link to comment
Share on other sites

Not totally but I don't mind keeping it.  I just am not interested in spending a whole pile of money on it. I'm ok with it, I don't ride this bike hard enough to be trail braking.  I do like the safety factor of it, placebo or not...

 

Link to comment
Share on other sites

I see that the 5th and 6th gen stainless line kits are different.  So yeah the valve dealio you were talking about is definitely a factor obviously.  The Stainless line kit may actually be a good solution as the lines are from 1998 that are on the bike now so that could be a factor.  I'm not sure that this is a cost effective solution compared to delinking and I also am not sure that I want to delink them either...

Link to comment
Share on other sites

  • Member Contributer
3 hours ago, Epyon007 said:

OK so while doing more research I found this delinking kit.  Anyone know anything about it?

 

Hel D-link kit

I have not seen this kit but would be interested in seeing the instructions. Me feeling is that they are basically bypassing the linked portions by looping back the linked feeds to the main feeds with short jumper lines with dual line banjo bolts. Not sure what they are doing with the SMC. Possibly replacing the plunger with a locking piece to keep in from activating when the front brake is activated. Either way, I'd ask for an instruction and/or full parts list sheet(s) to see exactly what's involved.

 

In all honesty, I like the linked brakes or more appropriately, do not find any issues with them. Once I put the SS lines, bled the system thoroughly and added new EBC HH pads, I found the braking system to be working very well.

Link to comment
Share on other sites

Yeah I don't mind the system really.  The cost of the stainless line kit is rather steep but with my stock lines likely still the originals from 98 replacing them would be good for safety and performance.  The prices of buying 6th gen calipers are so cheap that I may still look into doing the front conversion.  Also I like the gold calipers O:)

Link to comment
Share on other sites

  • Member Contributer

Honda tweaked the LBS system several times on different models--before ditching it entirely on the 8th gen!  I presume they improved it each time (the first version, which I had on a '93 CBR1000F, was rather primitive), so in theory, at least, fitting the 6th gen version to the 5th gen should result in an improvement.  Maybe.  As it is a mechanical system from a very similar bike, it would simply be a matter of swapping or modifying all of the components.  The caliper and master piston diameters can be found in the General Information sections of the Honda Workshop Manuals if you want to compare.   You could then compare the part numbers of the other components, but you may have to just buy the different parts and see.  Good luck!

 

Ciao,

Link to comment
Share on other sites

According to Bike Bandit I don't see that the pistons are different sizes.  Having another piston up front would be nice.  I'll have to look at some other 6th gens and see if I can just do the caliper swap up front and loose what ever plumbing I don't need...

Link to comment
Share on other sites

  • Member Contributer

According to the service manual the id of the caliper pistons is as follows:

5G

Left upper 25.4mm

Left mid 22.65

Left lower 22.65

Right upper 27.0

Right mid 22.65

Right Lower 25.4

 

6G

Left upper 25.4mm

Left mid 25.4

Left lower 25.4

Right upper 25.4

Right mid 22.65

Right Lower 25.4

 

So the 6G has the more consistent-sized set of pistons with the exception of the rear-linked right-middle piston.

 

 

 

Link to comment
Share on other sites

Fantastic Terry, thank you so much for your data.  Maybe it's time you change that whole ill informed opinions things ;).  Now I need to see about plumbing differences.  So lets see the total surface's are

L5 - 70.7

R5 - 72.05

 

L6 - 76.2

R6 - 73.45

 

Terry, do you have the Master cylinder sizes in your collection there by chance?

Link to comment
Share on other sites

20 hours ago, Duc2V4 said:

I have not seen this kit but would be interested in seeing the instructions. Me feeling is that they are basically bypassing the linked portions by looping back the linked feeds to the main feeds with short jumper lines with dual line banjo bolts. Not sure what they are doing with the SMC. Possibly replacing the plunger with a locking piece to keep in from activating when the front brake is activated. Either way, I'd ask for an instruction and/or full parts list sheet(s) to see exactly what's involved.

 

In all honesty, I like the linked brakes or more appropriately, do not find any issues with them. Once I put the SS lines, bled the system thoroughly and added new EBC HH pads, I found the braking system to be working very well.

In your experience with both generations do you think the calipers would be a straight swap?  They "look" like they would be.

Link to comment
Share on other sites

  • Member Contributer

I can see from looking at the part numbers for the brackets that the calipers mount to, they are the same on both 5 and 6G, so the calipers will fit straight on.

The ABS model has a different right caliper mount but same left; my guess is that would be to incorporate a wheel speed sensor pickup on the right, rather than any difference in the caliper mount.

 

Which size master to use? Bear in mind you need to look at the area not the diameter. So a 14mm vs 12.7, the area is 21% different, so for a given hand movement, the larger piston shifts 21% more fluid, which means a firmer feel and less ultimate power at the caliper.

 

Honda obviously looked at the relative master and slave areas for the 5G and 6G because if you do the math, the ratio of slave area/master area is reasonably similar at 15.7 (5G) and 16.4 (6G). If you were to use all 6 pistons, then the ratio for 5G is 22.1 and the 6G is 19.1. Just my opinion, but I think that using the 5G brakes would make for an overly grabby and soft system. A 6G master and 5G calipers gives a ratio of 18.1. I'd be cautious straying too far from what Honda deems a 'safe' setup, so my suggestion (and it is only that) would be to use the 6G master with the 5G calipers. 

 

I swapped the stock 14mm M/C on my ST1100 for the 12.7mm from my VFR (spare, because I fitted CBR600F4 brakes), because there was little power or feel to the stock brake, a bit like grabbing a brick. The smaller master gives the lever a softer feel and a bit more travel, but much more bite at the pads, which I prefer. It is nice to have the choice. This changed the ratio from 14.9 to 18.1.

 

Link to comment
Share on other sites

  • Member Contributer
1 hour ago, Epyon007 said:

In your experience with both generations do you think the calipers would be a straight swap?  They "look" like they would be.

Basically what Terry said. In all honesty I had considered looking at if the two were interchangeable but never really got around to it. If you really want I can do some quick measurements of the mounting holes to verify if they are the same. Probably wouldn't be able to do this until later in the day tomorrow (Monday) though.

Link to comment
Share on other sites

Duc - I imagine you could eyeball it and that would be good enough if you were bored hehe.

 

Terry - I guess my main issue with the current set up is that it doesn't seem like anyone is home until I get really deep into the lever and or I add the rear.  Then we are getting somewhere (err not getting anywhere really).  I do have HH pads and they seemed a little better for a while but then seemed to go back to being just ok.  Which I thought was very strange.  I know the stock set up isn't ever going to be superbike level braking.  When I rode my friends 6th gen it definitely felt better, as in it seemed to have more braking power and maybe better feel.  Now I may be falling into the trap that everyone who isn't educated about brake masters does in that I think it is doing more braking then it really is because of how I perceive it.

 

I would think that the extra piston working on the right side would help...

Link to comment
Share on other sites

  • Member Contributer

You may need nothing more than a good cleaning and system flush. I'd take the calipers apart and clean the pistons before spending anything on parts swapping. 

I bought a well used PC800 that had a similar feel to what you describe. There was a very distinct ring of buildup on the pistons. Once the previous owner replaced the pads and pushed that ring past the dust seal, it was a fight to get good brake pressure. 

Link to comment
Share on other sites

  • Member Contributer

Yeah, I'm coming late to this discussion but John (JZH) shared a Honda press document with the technical details of the 2002 VTec VFR. It included this discussion of the updates to the linked braking system:

 

Newly Revised ‘Sports’ Dual Combined Brake System

 

Equipped with one of the most advanced and compact versions of Honda’s

brake control-assisting Dual Combined Brake Systems, the VFR delivers a

confidence-inspiring balance of brake operation that brings it to a quick and

sure stop with an optimal balance of front and rear braking forces, whether the

rider uses both the hand and foot brake levers or only one of the two.

 

Since giving the VFR a more sporty balance of performance was one of the

foremost goals of its total redesign, attention was also paid to giving its

advanced brake system a more sporty and aggressive package of braking

characteristics. This was achieved, through careful evaluation, by re-routing

the lines controlling its calliper piston actions.

 

Where nearly all Dual Combined Brake Systems till now have the hand

brake lever controlling the two outer pistons of both front 3-piston callipers,

the new VFR’s front brake lever operates the two outer pistons of the left-side

front calliper and all three pistons of the right-side calliper, as well as the

centre piston of the rear brake calliper (by way of the secondary master

cylinder), resulting in more front-oriented braking response that feels more

closely matched to the aggressively responsive Super Sport road machine that

the VFR has always been.

 

The foot brake pedal that previously actuated the two outer pistons of the

rear brake calliper and both centre pistons of the front callipers now actuates

the same two rear brake calliper pistons, but only the one centre pistonof the

left front calliper. This revised balance of braking force is administered

through a direct-side proportional control valve (PCV) mounted inline

between the foot brake master cylinder and the rear calliper. During light

applications of the foot brake, most of the actual braking force is applied at the

rear wheel, with only the slightest amount of front brake input at the one leftside

calliper providing a steadying influence on the balance of front and rear

brake control without causing unsettling shifts of weight and its related frontend

dive. However, this balance of operation changes in response to strong

pedal operation, in which case the system adjusts for an optimal balance of

front and rear braking forces.

 

As in other Dual Combined Brake Systems, the compact secondary master

cylinder integrated into the left-side calliper’s pivoting mount increases rear

calliper brake pressure through a servo-side PCV as its own braking forces

increase in response to front brake lever actuation. This results in a smoothly

progressive application of combined braking forces that starts with greater

emphasis on the front brakes and gradually but firmly applies a balancing

amount of rear braking force whenever the situation calls for it.

 

Taken together, these two brake operation scenarios provide a more

aggressive distribution of braking forces that both enhances braking

confidence for a wider range of riders and skill levels, and provides a more

familiar combination of braking characteristics for hard-core riders who insist

that their own braking skills are second to none.

 

Link to comment
Share on other sites

I don't know if it's PR hype or not but I felt like it made a difference.  I don't have the money to do all the swaps now with major suspension upgrades in the works but I'm going to ride my friends 6th gen again to see if  I get the same impression.  Then I do a brake flush to see if that helps much, the fluid looks great in the reservoir but that may not mean much.

Link to comment
Share on other sites

  • Member Contributer

I think Kevcarver is on the money with his suggestions that some caliper maintenance is due. I'd certainly suggest as a minimum that you check the sliding pins are all clean and well lubed, and then move to the pistons if needed. My own experience with the 5G brakes was that they were pretty darned good, plenty of power and very good stability. Saying that, I always include some foot brake with the front, so always had the full 6 pistons up front working for me. My only purpose for the delink was to reduce clutter and unsprung weight, and to replicate the brake setup that I love on my VTR1000 (which uses CBR954 calipers and master). 

Link to comment
Share on other sites

  • Member Contributer

It's always easier to start with the "free" stuff first. 

I never got mine to feel great, but I've ridden other 5th Gens that are rock solid with stock parts. 

The 6th Gens I've ridden have a different feel to them. Similar to the difference I've read described on SP1 and SP2. Second ones are said to be more progressive. Felt to me that at a steady pressure the braking increased. With 5th and SP1 steady pressure yields steady braking, and increased pressure is required for increased braking. That's my preference. 

I have SP1 front end on my VFR and owned an SP1 for a few years. 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy.