2ndGen Masters on a 1stGen

[Condor]

OK, I'm thinkin' since both of the '83's sight glasses in the OEM master reserves are one step above swiss cheese I'd either replace them with another set of OEMs, or.... replace them with a set of 2ndGen masters and levers... which I have already. Has anyone ever comtimplated doing this, or possibly even done it?? Can anyone think of a reason why not?? Any input would be appreciated.... Thanks..

[Squeeze]

- Handle Bar Diameter is different. 1Gen have 22mm(7/8"), 2Gen is 1".

 

- the Brake Master on the 2Gen is 5/8"(15,87mm) Piston Diameter, the 1Gen is 14mm. That's a Show Stopper.

[Condor]

- Handle Bar Diameter is different. 1Gen have 22mm(7/8"), 2Gen is 1".

 

- the Brake Master on the 2Gen is 5/8"(15,87mm) Piston Diameter, the 1Gen is 14mm. That's a Show Stopper.

 

I had thought about that and figured I'd just shim the 2ndGens.... I have some stainless 1" tubing... boat stuff ya know ... that should do the trick...

How would the bigger piston effect the braking??

[friesman]

Hi Jack

I am far from bein any kind of a mechanic and maybe I am missing something, but i cant see why that wouldnt work,

 

Brian

[Squeeze]

I had thought about that and figured I'd just shim the 2ndGens.... I have some stainless 1" tubing... boat stuff ya know ... that should do the trick...

 

How would the bigger piston effect the braking??

 

We had a Discussion about shimming the Masters 18 Months ago or so. You had no Fear, and i said, i can't say anything for a Fact, but even while I'm doing a Lot of Parts modifying, i wouldn't do this. I'm afraid of the Master turning down and not able to reach the Levers when i need to. Those M6 Bolts and the Brackets are not able to transfer much of clamping Force before they brake in two Pieces.

 

A too big Piston Size makes up a "digital" Brake. There's not much Travel between the Point where the Brake barely engages and where it bites to Point of locking up. Depends on what Brake Calipers we talking here. The newer the Calipers are the more digital the Brake Sensation will be.

[Condor]

We had a Discussion about shimming the Masters 18 Months ago or so. You had no Fear, and i said, i can't say anything for a Fact, but even while I'm doing a Lot of Parts modifying, i wouldn't do this. I'm afraid of the Master turning down and not able to reach the Levers when i need to. Those M6 Bolts and the Brackets are not able to transfer much of clamping Force before they brake in two Pieces.

 

A too big Piston Size makes up a "digital" Brake. There's not much Travel between the Point where the Brake barely engages and where it bites to Point of locking up. Depends on what Brake Calipers we talking here. The newer the Calipers are the more digital the Brake Sensation will be.

 

I think I do remember something like that, but usually I can't remember what I talked about yesterday let alone 18 months ago. This set of 2ndGens are off a '99. There isn't a whole lot of difference between 14mm and 15.87 in the bore size. 2mm isn't that much. I would think leverage would be a bigger factor on the hydralic caliper presure than volume. My brake lever compresses about 2"/50mm with the OEMs. Push 20% more fluid thru the line and it might reduce the throw to 1.5"/37mm?? ...Rough estimates... And remember I just installed the R1 front brake caliper. On the clutch master I don't think it makes all that much difference??? Thanks for the input Squeeze. I guess the only way to tell for sure is do the swap. If it's going to try and send me over the windshield I can always undo everything.

[dingy]

I looked at doing it to get the larger piston size.

 

It appears the attachment angle to the handlbar was different also, aside from what Squeeze mentioned about diameter.

 

I would think the larger bore size would be a plus.

 

 

[ATTACH]39898[/ATTACH]

RSV master

 

[ATTACH]39899[/ATTACH]

1st gen master

 

 

Gary

Edited January 4, 2010 by dingy
spelling

[dingy]

I think I do remember something like that, but usually I can't remember what I talked about yesterday let alone 18 months ago. This set of 2ndGens are off a '99. There isn't a whole lot of difference between 14mm and 15.87 in the bore size. 2mm isn't that much. I would think leverage would be a bigger factor on the hydralic caliper presure than volume. My brake lever compresses about 2"/50mm with the OEMs. Push 20% more fluid thru the line and it might reduce the throw to 1.5"/37mm?? ...Rough estimates... And remember I just installed the R1 front brake caliper. On the clutch master I don't think it makes all that much difference??? Thanks for the input Squeeze. I guess the only way to tell for sure is do the swap. If it's going to try and send me over the windshield I can always undo everything.

 

 

Actually there is about a 28% increase in size from a 86-93 to a RSV

 

Below is a drawing I did for comparision.

 

Top line is bore size

 

Second line in MM Sq.

 

Third line is increase from 83-85 size.

 

Gary

[Squeeze]

Jack, I don't know if you delinked the Brakes also, but be assured, feeding two R1 Calipers with a 5/8 Master is too much. Let alone, feeding only one R1 Caliper. I've been there.

 

I don't know enough about your riding Style and Braking Habits, but if you getting on it in the Twisties once in a while, you not going to be happy with such a Setup. Riding in wet Conditions isn't any Fun too.

 

If you want to upgrade your Masters, take those from a earlier FJR 1300. They fit both to the Handle Bars and have adjustable Levers, plus the early Masters are 14mm. The Piston Size is casted in Letters near the Banjo Bolt, mostly on the underside of the Master.

 

If you don't trust me alone, OK, ask Pegscraper, we've been through this on his Bike too, he WAS in Doubt also.

 

Dingy, again, i really like your Approach. The Comparison between the Areas is one Key. 1.87 mm doesn't sound much but it makes World of Difference. Now, if you compute the Area Data with the different Leverages those Masters have, it would be perfect.

[Squeeze]

Oh, and to add, i feed both R1 Calipers on the front of my '93 with the stock 14mm VR M/C. Works just fine.

[dingy]

Dingy, again, i really like your Approach. The Comparison between the Areas is one Key. 1.87 mm doesn't sound much but it makes World of Difference. Now, if you compute the Area Data with the different Leverages those Masters have, it would be perfect.

 

I could probably work this out if I had some additional info.

 

I would need the distance from the brake lever pivot point in the master cylinder housing to the center line of contact with the plunger in master cylinder housing.

 

The length of the brake lever from the pivot point would be helpful to create a graph with. With this I could show what 1" of tip movement would create in fluid displacement.

 

This will vary for each different master cylinder, 83-85 ,86-93 & RSV.

 

I can get the 83-85. But what would be ideal is if one person could get all three measurements, this way they would all be taken using the same methodology.

 

Gary

Edited January 3, 2010 by dingy
quote messed up

[Condor]

I could probably work this out if I had some additional info.

 

I would need the distance from the brake lever pivot point in the master cylinder housing to the center line of contact with the plunger in master cylinder housing.

 

The length of the brake lever from the pivot point would be helpful to create a graph with. With this I could show what 1" of tip movement would create in fluid displacement.

 

This will vary for each different master cylinder, 83-85 ,86-93 & RSV.

 

I can get the 83-85. But what would be ideal is if one person could get all three measurements, this way they would all be taken using the same methodology.

 

Gary

 

I'd be intrested in what the R1 masters are in bore size also Gary. And it may very well be better to install a set of MKII masters to improve performance since they are a larger bore than the MKI's. In answer to Squeezes query about delinking the brakes. Nope, everything is '83 stock as a rock except for the R1 Caliper mod. Squeezes suggestion about trying an early set off an FJR1300 might be a better way to go?? I'll look into those as well. I just thought the G2 masters were better looking than what's on there, and one of those triple accessory switch housings from Kuryakyn would have been in the future.

[GaryZ]

Can you add a pressure regulator?

[dingy]

Attached is a file containing a compilation of brake specifications.

 

83-85 Venture

 

86-93 Venture

 

99-09 Rsv

 

2002 FJR

 

R1 (? year)

 

85 VMax

 

Master Cyl dia., Caliper dia., Rotor dia. (all in millimeters)

 

As a good actor once said "Trust, But Verify" This list is for reference only.

 

I pulled info from various service manuals.

 

Gary

Edited June 21, 2011 by dingy
updated chart

[Thom]

i have been looking for fjr m/c and all i have found are the ones with the plastic res. and the cast on my 1 gen Mk2 m/c is 5/8 . i have the R1 mod and it is delinked , kind of a let down because i have to use a lot of lever pull and if i pull to hard it is graby . i was thinking about a bigger m/c with a longer lever mite help . i have never locked up the front tire and i have tried while moving .

what size m/c do the R1's use ? JimBob is using a m/c off a Sussy .

Jack , if you try it and shim the G2s don't use the steel tubing use the 1 in alum. , it is softer and will grab better .

[Thom]

thanks dingy ! so the R1 and the fjr are 14 mm too but what is the amount of fluid they are pushing ? the pistons are 14mm around but how long is the stroke ? or how many cc's of fluid is being pushed ?

[talonsx2]

I remember reading a post at one time of someone replacing the sight glass with the crystal (Glass) from a watch? Does anybody else remember this?

 

Mike:225:

[Condor]

I remember reading a post at one time of someone replacing the sight glass with the crystal (Glass) from a watch? Does anybody else remember this?

 

Mike

 

Yep, I remember that thread, and thought about that as an option. But I had a set of these nice looking 2Gen masters laying here..... If it gets to be to much of a hastle I may just go with a set of clean MarkII's for the 14mm bore, which is the same as the R1/R6 master, to match the R1 Caliper. I might even go with a little larger MKII rear master but keep the rear MKI caliper.

 

On the shim I thought I might check with Earl to see if he might be able to machine me up a couple of 7/8"ID to 1"OD shims out of aluminum.

 

All this for a couple of cheesy sight glasses......

Edited January 4, 2010 by Condor

[dingy]

[ATTACH]39923[/ATTACH]

 

Attached is a drawing of an 83 brake handle.

 

1" tip travel generates .1145" (2.9094 mm) of plunger travel.

 

This calculates out to 368.55 cubic mm (pi * radius sq * height) (3.1415 * 40.3225 * 2.9094).

 

I can do this for the other models in question if I can get a scan of the brake handles in jpeg format.

 

I can import the handle into my CAD program and draw the geometry over the scan.

 

This will provide a comparison of the various brake units operational characteristics.

 

Gary

[Condor]

One thing that has come out of this whole thing is that if anyone does the 83-85 to 86+ fork/R1/MKIIrotor transplant the brake master will need to be changed as well. The MKI master is smaller, and the MKII 14mm model master will be needed to match the 4 piston R1 caliper. I always thought the masters were the same.?? Also along that same vain if the anyone delinks the brakes so that the front master does all the work on 2X4 piston calipers, a larger 2ndGen master may be in order??? Gary I'm really impressed with the wealth of info you've been posting on this subject. Maybe a 2Gen owner can take a pic of their front master and post it??

[dingy]

Gary I'm really impressed with the wealth of info you've been posting on this subject. Maybe a 2Gen owner can take a pic of their front master and post it??

 

A scan will be much more helpful, but I could work with a photo if I had some dimensions on it.

 

The scan I can import into my CAD at a 1:1 scale.

 

The photo is a different critter though.

 

Gary

[a1bummer]

Hey dingy...

You state that the front caliper pistons on an MKII are 32.10/33.96. I know that they are 2 piston calipers. Now does that mean that both pistons in the caliper on the left side are a different size than both the calipers pistons on the right? Or does that mean in one caliper the two pistons are a different size? I'm assuming both pistons in one caliper are the same size. And the difference would be in left or right calipers due to "linked" brake system.

 

Just curious

 

Oh ya, if ya can put a ruler or tape measure in the picture next to the levers, you can use that to find the actual dimensions of the lever.

[dingy]

Hey dingy...

You state that the front caliper pistons on an MKII are 32.10/33.96. I know that they are 2 piston calipers. Now does that mean that both pistons in the caliper on the left side are a different size than both the calipers pistons on the right? Or does that mean in one caliper the two pistons are a different size? I'm assuming both pistons in one caliper are the same size. And the difference would be in left or right calipers due to "linked" brake system.

 

Just curious

 

Oh ya, if ya can put a ruler or tape measure in the picture next to the levers, you can use that to find the actual dimensions of the lever.

 

I didn't know how to interpret front caliper sizes for RSV, FJR & R1.

 

The 83-85 has dual piston.

 

The 86-93 detailed in manual, Right/Left with different sizes.

 

The RSV, FJR & R1 just listed two different front sizes.

 

Attached below is cut from manual showing brake specs, at bottom of each sheet is model ID

 

 

Putting a ruler in picture will work. I would need the photo to be straight down on the handle.

 

Gary

[skydoc_17]

Hey A1Bummer,

On the MKII VR BOTH front Calipers are 4 piston Calipers. The Caliper on the right side, (activated with the right side hand lever) has 4 pistons that are 33.96MM in diameter.

The left front Caliper, (activated by the foot pedal in conjunction with the rear Caliper on the linked system) has 4 pistons that are 32.10MM in diameter. The rear caliper on the MKII is a 4 piston Caliper with all 4 pistons being 33.96MM in diameter. The problem that I discovered with the stock MKII calipers is the 2 piece design. (right and left caliper halves, bolted together) which caused brake fade at the beginning of a braking cycle, (caliper halves flexing) then caliper lock-up due to caliper collapse. (the 2 caliper halves coming back together after they reach full flex) This is why I went to the R1 Calipers. One piece design, progressive piston engagement, multiple piston sizes in each caliper, better rider "feel" at the brake lever. I also found that the bike stops faster and straiter with both front calipers working together and the rear caliper working with the foot pedal. The last thing I found was that I was able to take better advantage of the use of the "friction zone" with the rear caliper disconnected from the left front caliper. This suited my riding style MUCH better.

I hope this answers your questions,

Earl

[warthogcrewchief]

Hey A1Bummer,

On the MKII VR BOTH front Calipers are 4 piston Calipers. The Caliper on the right side, (activated with the right side hand lever) has 4 pistons that are 33.96MM in diameter.

The left front Caliper, (activated by the foot pedal in conjunction with the rear Caliper on the linked system) has 4 pistons that are 32.10MM in diameter. The rear caliper on the MKII is a 4 piston Caliper with all 4 pistons being 33.96MM in diameter. The problem that I discovered with the stock MKII calipers is the 2 piece design. (right and left caliper halves, bolted together) which caused brake fade at the beginning of a braking cycle, (caliper halves flexing) then caliper lock-up due to caliper collapse. (the 2 caliper halves coming back together after they reach full flex) This is why I went to the R1 Calipers. One piece design, progressive piston engagement, multiple piston sizes in each caliper, better rider "feel" at the brake lever. I also found that the bike stops faster and straiter with both front calipers working together and the rear caliper working with the foot pedal. The last thing I found was that I was able to take better advantage of the use of the "friction zone" with the rear caliper disconnected from the left front caliper. This suited my riding style MUCH better.

I hope this answers your questions,

Earl

 

 

Thanks for the clarification! I was wondering if I would need to upgrade my master brake reservoir if I do the R1 brake mod.