Brake upgrade?

[OldBear]

Has anybody done the upgrade to R1 brakes on a 2nd gen? I went with stainless brake llines shortly after I bought my bike, 'cause the brakes felt awful "soft" after my FJR and Duc. The stainless lines really helped, but I am curious about going to the R1 brakes. They "should" help quite a bit. Ideas?

[1BigDog]

I have the R1 upgrade on my 99 along with a Vmax splitter. So far im satisfied with it. Braking improved maybe 15-20% over stock but that also includes the addition of SS lines. Hard stopping improved overall compared to the stock brakes. Havent had them lock up either. Looks cool too!

[Condor]

I have the R1 upgrade on my 99 along with a Vmax splitter. So far im satisfied with it. Braking improved maybe 15-20% over stock but that also includes the addition of SS lines. Hard stopping improved overall compared to the stock brakes. Havent had them lock up either. Looks cool too!

 

I'm about ready to mod my '99 with the R1's. Is it just a plug and play situation or is there a rotor issue? I did it on my 1stGen '83, and had to replace the rotors, so just double checking to see if the stock Gen2 rotors are compatable with the R1's??

[skydoc_17]

Along with the improvement in braking power, you will find you will get extra life out of your pads as well, there will be no more switching your pads around to the movable piston side of the caliper! The R1 Brake Swap will work just fine with the stock rotors, but the stock brake splitter has got to go! My kit provides the replacement splitter and the Stainless Steel Splitter Bracket to mount the new splitter in the proper location.

 

http://www.venturerider.org/classifieds/showproduct.php?product=2445&title=2nd-gen281996-2010-29-r1-caliper-swap-and-s-sbrake-lines-21&cat=7

 

If you want to furnish your own Stainless Steel brake lines or R1 Calipers, I sell the Brake Splitter and Stainless Steel Splitter Bracket Separate.

Another thing to mention is stock organic and Kevlar pads are NOT the way to go with this upgrade, you are going to want to use the HH Sintered Pads from EBC. I sell those pads separate as well.

Two RSV's Side by side, driven to 65 MPH then "Panic Stopped", one with fresh stock brakes and one with the R1 Upgrade netted between 16 to 20 feet shorter stopping distance with the R1 upgraded bike, WITHOUT LOCK-UP, EVERY TIME!

I would be happy to answer any questions about this R1 brake swap or if you need parts, please Feel free to PM me.

Earl

Edited August 3, 2010 by skydoc_17

[1BigDog]

I'm about ready to mod my '99 with the R1's. Is it just a plug and play situation or is there a rotor issue? I did it on my 1stGen '83, and had to replace the rotors, so just double checking to see if the stock Gen2 rotors are compatable with the R1's??

 

Stock rotors work just fine. Just remember that the R1 calipers eliminate those caliper brackets. Bolt them directly to the fork bosses. I also replaced the rear line with a SS one and rebuilt my rear caliper with fresh HH pads as well. Clutch SS line too. Flushed the whole system with Motul DOT 5.1 brake fluid, which has a higher boiling point then DOT4. (not to be confused with synthetic 5 fluid). Earl has a nice kit. You wont be disappointed.

[Condor]

Stock rotors work just fine. Just remember that the R1 calipers eliminate those caliper brackets. Bolt them directly to the fork bosses. I also replaced the rear line with a SS one and rebuilt my rear caliper with fresh HH pads as well. Clutch SS line too. Flushed the whole system with Motul DOT 5.1 brake fluid, which has a higher boiling point then DOT4. (not to be confused with synthetic 5 fluid). Earl has a nice kit. You wont be disappointed.

 

Thanks for the advice Ruffy. I already have a set of R1's loaded with new HH pads. Picked them up off Ebay for next to nothing. R1 and R6 calipers are always on there. I think I'll leave the back alone as some already have a tendency to lock up when romped on. I haven't hit 'm hard yet, but you never know. Speed bleeders too....

[pegscraper]

When the R1 calipers are installed on the RSV, they also need to be complemented with a 14mm master cylinder that can be found on a later model Roadstar that had these same calipers. This M/C matches our stock one exactly in looks, but it will have a 14 beside the inspection window instead of 5/8. The stock 5/8" M/C can be used, but you will be disappointed and wonder what the rave is all about. With the proper 14mm M/C, these brakes are fantastic. Don't use these rotors without the properly sized 14mm M/C.

 

Check your FJR which has these same calipers and you will find that it has a 14mm M/C on it too.

 

For rotors, I recommend bolting on a set of R1 floating rotors and getting rid of the stock solid ones.

[Condor]

When the R1 calipers are installed on the RSV, they also need to be complemented with a 14mm master cylinder that can be found on a later model Roadstar that had these same calipers. This M/C matches our stock one exactly in looks, but it will have a 14 beside the inspection window instead of 5/8. The stock 5/8" M/C can be used, but you will be disappointed and wonder what the rave is all about. With the proper 14mm M/C, these brakes are fantastic. Don't use these rotors without the properly sized 14mm M/C.

 

Check your FJR which has these same calipers and you will find that it has a 14mm M/C on it too.

 

For rotors, I recommend bolting on a set of R1 floating rotors and getting rid of the stock solid ones.

 

When I did the '83, I kept the stock... smaller... OEM master, and there was still a big increase in the upgrade to the right front. I also didn't do a thing to the rear linked master or the rear caliper for the left front, and it worked just fine with better braking. With 14mm actually being smaller than the larger RSV 5/8ths master, why would you want to decrease the size when you have 4 more pistons to move with the R1's??

[pegscraper]

My post primarily refers to the Royal Stars and RSVs. I don't know what the 1st gens have on them.

 

The R1 calipers are designed to be used with a 14mm bore M/C. That size against whatever the total R1 caliper piston area is creates a certain mechanical advantage ratio. Use those calipers with a 5/8" bore, and yes, it will work, but barely. It won't even be as good as stock. The mechanical advantage ratio is wrong, requiring way too much effort on the brake lever to make them work. The force multiplication that the correct ratio has is gone and you can't get enough force on the caliper pistons to make them work well.

 

When I first put the R1 calipers on my bike, I wondered what the big deal was with the M/C. My stock one works fine. I'll use that and save the money. Riding the bike with that setup was scary. The brakes didn't work worth a crap and I wondered why everyone thought these were so great. I decided to try a 14mm M/C just to see what happened. I had one within a week and it made all the difference. This bike feels like I could stand it on its nose if I had the skill for that. I don't. So I guess the decision of which M/C to use is up to the one doing it. One can do it the long way and figure the reasons out for himself why a 14mm M/C is needed, or one can learn from the experience of others and do it correctly from the start.

[Condor]

My post primarily refers to the Royal Stars and RSVs. I don't know what the 1st gens have on them.

 

The R1 calipers are designed to be used with a 14mm bore M/C. That size against whatever the total R1 caliper piston area is creates a certain mechanical advantage ratio. Use those calipers with a 5/8" bore, and yes, it will work, but barely. It won't even be as good as stock. The mechanical advantage ratio is wrong, requiring way too much effort on the brake lever to make them work. The force multiplication that the correct ratio has is gone and you can't get enough force on the caliper pistons to make them work well.

 

When I first put the R1 calipers on my bike, I wondered what the big deal was with the M/C. My stock one works fine. I'll use that and save the money. Riding the bike with that setup was scary. The brakes didn't work worth a crap and I wondered why everyone thought these were so great. I decided to try a 14mm M/C just to see what happened. I had one within a week and it made all the difference. This bike feels like I could stand it on its nose if I had the skill for that. I don't. So I guess the decision of which M/C to use is up to the one doing it. One can do it the long way and figure the reasons out for himself why a 14mm M/C is needed, or one can learn from the experience of others and do it correctly from the start.

 

Ok would you please explain to me why there's a huge mechanical advantage gain by using the smaller 14mm master over the larger OEM 5/8ths (15.87mm) master on an RSV?? I always understood that the mechanical advantage came from the lever configuration, and the voluum came from the master bore... I'm always ready to learn.

[pegscraper]

A lesson in hydraulics? Let me think about how to explain it simply. Maybe I can work up an illustration. I don't have internet at home right now, having account problems, and my time on anything is really limited. Let me get back to you.

[KiteSquid]

it has to do with the ratio of the bores and strokes of the master to slave cylinders.....

[pegscraper]

Well, I still don't have a diagram, but to elaborate on what kitesquid started... it's a matter of the ratio between the areas of the M/C piston and all the caliper pistons. In this case, the area of the calipers pistons is fixed and we have two different possible M/C sizes, one with a 5/8" bore and one with a 14mm bore. The larger M/C bore will move more fluid and move the caliper pistons further for a given lever travel. This kind of ratio also has the effect of requiring more effort to squeeze the pistons against the rotors. The effort required is so great as to make the brakes feel like they don't work very well. The smaller M/C bore will require more lever movement for a given caliper piston travel, which also reduces the effort needed to pull the lever and multiplies the force transferred from the lever to the calipers. The increased lever movement with the 14mm M/C is not noticeable. What is noticeable is the tremendous increase in stopping power and the fact that these brakes can be operated with two fingers. I strongly recommend using the 14mm M/C with the R1 calipers. They're a matching system and it's the way Y used them from the factory.

[Condor]

OK, I can see where you're going with this, but I'm not completely sold on the big difference between the two masters. We're talking about less than a 2mm bore increase. I understand that Y uses the 14mm on their lighter sport bikes, and because they are a lighter bike they might not need the bigger master. Going to the R1 or R6 on the RSV does increase the number of pistons from 2 to 4, and I'm sure that does come into play with better braking performance. That's the reason for going to the R1/R6's in the first place. I guess I'll just have to find out for myself if there actually is a positive result in the switch, and if I'm wrong I'll definately know what to do..... Thanks

[pegscraper]

Two mm doesn't sound like much, but in this case it makes a world of difference. I probably would have had a hard time believing the difference it makes too just by someone telling me if I had not tried both M/Cs myself. BTW, Y doesn't use what we're calling R1 calipers just on sport bikes either. The exact same setup is also used on the FJR as well as the later model Roadstars, Warriors, Roadliners, Stratoliners, and Raiders if I haven't missed any models. And they all have a 14mm M/C to go with them. Frankly, the calipers off of one of these other cruiser models would probably look better on our bikes than those from an R1 too.

[dingy]

As the plunger diameter in the master decreases,the PSI increases, with less flow volume being created.

 

What this translates to is with the same amount of pressure on the brake lever the force imparted on the caliper pistons will be higher with a smaller master plunger. It also means that the lever will need to travel further to move the caliper pistons the same distance.

 

This is standard hydraulics theory. If you want high flow, use a large plunger. If you want high pressure, use a small plunger. This is assuming the same amount of input force is been applied to the system.

 

Somewhat like taking a garden hose and putting your thumb on the end. This is similar to reducing the plunger size. Now the water coming out is at a higher pressure, but much less volume.

 

Gary

[Condor]

Then.... since Y chose to use the 14mm on so many different models, why did they use the 5/8" on the heavy RSV??

[dingy]

Then.... since Y chose to use the 14mm on so many different models, why did they use the 5/8" on the heavy RSV??

 

I believe that the front calipers on the RSV only have two pistons on one side of each caliper. On the 1st gen MKII's there are 4 pistons, two on each side of each caliper. Unlike the MKII's the RSV is now controlling both front calipers, no unified braking system.

 

End result is basically the same surface area is being driven by the front master.

 

But now, with both front calipers being activated by the front master, the total front braking force increases via the front master. There was probably a design decision to reduce the PSI on the front brakes to reduce lockup.

 

The rear brake master went from a 17.46 mm master to a 12.46 mm. This would reduce the amount of fluid flow, due to rear no longer tied to front brake. It would have also increased the PSI. The rear brakes are still a 4 piston arrangement on the RSV, same as MKII. They may have made a design change in the rear brake linkage to reduce the mechanical force on the piston, so as to lower PSI that is transmitted to rear caliper. I'm am just speculating about this though. They may not have as I recall some here have modified the rear brake by inserting a flow valve in series with the rear caliper to reduce lockup.

 

Gary

[Condor]

So, if I understand you right, the idea was to decrease front brake lock up by using the 5/8" master, which is a good thing, but by reducing the size of the rear master they've created a situation were rear lock up is not that uncommon. and panic high-siding is a possiblity.... which is a bad thing. So why not at least stick with the 5/8" front master and reduce the possibility of locking up the fronts?? And reducing the sensitivity to the rear delaying the sudden high PSI flow via Rick Buttler's mod?? Or... find a larger rear master that's compatable??

[pegscraper]

Then.... since Y chose to use the 14mm on so many different models, why did they use the 5/8" on the heavy RSV??

 

Because of the calipers used and the areas of the pistons. The 5/8" M/C goes with the stock style calipers. The 14mm M/C goes with the R1 style calipers. And it's really best to use them that way and not mix and match parts.

[RedRider]

For an easy explanation of how 2 mm of diameter can make a difference -

 

Force = pressure x area

 

Area = pi x 1/4 x diameter^2 (^2 is qwerty keyboard speak for 'squared')

 

Therefore:

 

Force = pressure x pi x 1/4 x diameter^2

 

Brake pad force against the rotor is a squared relationship to the diameter of the M/C plunger. Small change makes a big difference.

 

OK, back to work.

 

RR

[RSTDdog]

Area of a circle is pi x radius squared. Radius is 1/2 diameter.

Thus pi x (1/2 Diameter) squared.

 

The pressure (pounds per square inch) out of the master cylinder is equal to the force applied on the lever x the area of the piston.

 

So pressure(psi)= Force(pounds) x Area

 

10psi= 10lbs x 1 square inch

15psi= 10lbs x 1.5 square inches (or 15 lbs x 1 square inch)

 

The above are examples, but the 5/8 (15.8mm) master cylinder will make more pressure than the 14mm master cylinder with the same force applied to the bore piston and equal stroke.

 

I agree with using the parts matched the way Yamaha designed it.

 

Now I just want to know why its that way. The above is simplified and doesn't take into account fluid dynamics or differences in the stroke length. A question for Mr. Google perhaps...

 

Rstddog

[dingy]

Area of a circle is pi x radius squared. Radius is 1/2 diameter.

Thus pi x (1/2 Diameter) squared.

 

The pressure (pounds per square inch) out of the master cylinder is equal to the force applied on the lever x the area of the piston.

 

I disagree, the force on the lever is not the same as the force on the end of the plunger, due to pivot points on lever.

So pressure(psi)= Force(pounds) x Area

 

Formula is Force (Pounds) / Area (Square inches)

 

http://www.engineershandbook.com/Tables/fluidpowerformulas.htm for reference

 

10psi= 10lbs x 1 square inch

 

Correct

 

15psi= 10lbs x 1.5 square inches (or 15 lbs x 1 square inch)

 

6.66 PSI = 10lbs / 1.5 square inches

 

The above are examples, but the 5/8 (15.8mm) master cylinder will make more pressure than the 14mm master cylinder with the same force applied to the bore piston and equal stroke.

 

I disagree, a 5/8 dia. (15.8mm) master will generate less PSI, but with more flow than a 14 mm master with the same force applied to the bore piston and equal stroke.

 

I agree with using the parts matched the way Yamaha designed it.

 

Now I just want to know why its that way. The above is simplified and doesn't take into account fluid dynamics or differences in the stroke length. A question for Mr. Google perhaps...

 

Rstddog

 

I will admit Hydraulics is not my best subject, but I did spend 6 years designing centrifugal & reciprocating pumps.

 

An analogy to the relationship between the plunger (driving) area and applied force to the plunger is to think of having a large common nail in your hand, one with a head on one end and a point on the other. Grasp this nail at the shank and place it against your arm with the large head on the arm and apply some pressure to the shank towards your arm. Now, flip the nail over, with the point towards your arm, and apply the same pressure to the shank of the nail. You will notice that with the point towards your arm, it hurts more. This is because the contact area has been reduced and there is now higher PSI being imparted on your arm. PSI = Force / Area http://www.engineershandbook.com/Tables/fluidpowerformulas.htm

The same thing happens with a plunger in a master cylinder. As the surface area of the plunger decreases, the amount of PSI imparted on the hydraulic fluid increases, given the same force pushing the plunger.

 

I made a drawing below illustrating an example of this.

 

The force imparted on the piston would be a measurement of the increased force between the top of the piston and the bottom of the caliper.

 

The force on the plunger would be the same as putting a 30 pound weight on the plunger with the body in a fixed position.

 

I did not show seals, reservoir or bleeders here.

 

What Pegscrapper said about keeping system components together is a good practice. Where this gets thrown out the window is when someone with an MKI wants to upgrade the brakes and delink the front and rear.

 

Gary

 

 

http://i1007.photobucket.com/albums/af193/gdingy101/hydsystem.jpg

[RSTDdog]

Gary,

 

Thanks for taking time to do that. I got my terms turned around. That makes sense to me now.

 

On an RSV or TD, why would the type of splitter used matter Stock vs Vmax or other? Anytime I have changed brake lines on other bikes, they just seem like a manifold to me, 1 in 2 out, straight through.

 

Thanks,

 

Derrek

[dingy]

Gary,

 

Thanks for taking time to do that. I got my terms turned around. That makes sense to me now.

 

On an RSV or TD, why would the type of splitter used matter Stock vs Vmax or other? Anytime I have changed brake lines on other bikes, they just seem like a manifold to me, 1 in 2 out, straight through.

 

Thanks,

 

Derrek

 

 

None I hope.

 

I am using an RSV splitter on my 1st gen. I put MKII brakes on, front and rear. Put on all stainless lines.

 

I had to custom mount splitter, but it is working fine.

Gary