2ndGen Masters on a 1stGen

[Condor]

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

 

Since the MKII master on your '89 is the same size as the R1 master there isn't a need to up grade. The need to up grade would be for the smaller '83 MKI master, which from a lot of reports is inadiquate to begin with. In the case of the MKII/R1 mod it's the easiest mod to do. Just R&R the calipers and bleed, unless you feel a need to de-link the brakes. Personally with all the stuff that had to be done to my '83 I still didn't feel there was a need. At a later time I might replace the rear master with a MKII, but I'm going to have to do a little research to see if there's actually a difference between the rear I & II??

[a1bummer]

Hey A1Bummer,

On the MKII VR BOTH front Calipers are 4 piston Calipers.

 

Ya, I knew that. For some reason I keep thinking of only one half of the calipers. MKI has 2-piston calipers and the MKII has 4-piston calipers. Thanks for the reminder. Probably due to all the years of working on cars where they usually have a piston or pistons on one side of the calipers.

 

That's my story and I'm sticking to it.

 

And thanks for the clarification on the piston sizes too. That's what I was picturing in my head. Now I have to wonder about the people who are putting both front calipers on the front master cylinder. One caliper would grab before the other and cause the forks to twist and pull the bike to one side. So I would think anyway.

 

But now that I think about it some more, I'm guessing that similar happens when I hit just the front brake or just the linked brakes. I better just quit thinking maybe.

Edited January 6, 2010 by a1bummer

[a1bummer]

On a second note. I see that the MKI, RSV, FJR and R6 all have 298mm diameter front rotors. Are any of them interchangable with the MKI's front/rear potors?

[dingy]

On a second note. I see that the MKI, RSV, FJR and R6 all have 298mm diameter front rotors. Are any of them interchangable with the MKI's front/rear potors?

 

 

83-85 rotor thickness is 8.5mm

 

86-93 rotor thickness is 7mm

 

rest are 5mm

 

one millimeter is .039" for reference, about half the thickness of a nickel.

 

Gary

[Condor]

On a second note. I see that the MKI, RSV, FJR and R6 all have 298mm diameter front rotors. Are any of them interchangable with the MKI's front/rear potors?

 

I had to install MKII rotors for the R1 calipers. The MKI's are cooled by internal viens and thicker, while the MKII's rely on gaps in the rotor face for cooling. The R1 calipers also don't have the pad dust cover like those found on the MKI caliper. I thought they might have been missing from the R1 set I had, but someone straightened me out...Squeeze I think....and they are left off for better air flow.

[Squeeze]

On a second note. I see that the MKI, RSV, FJR and R6 all have 298mm diameter front rotors. Are any of them interchangable with the MKI's front/rear potors?

 

YES, all of them will fit much better to the MKI. Not sure if the rear Rotor on the MK1 is a straight Type or if those are set off Style.

 

The different Thickness is because the the MKI Discs are rigid and air vented, whereas the newer Bikes all are bored and have "floated" outer Rings where the Pads are biting to.

[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

 

Since my acquisition of a 1988 parts bike I have been able to add the 1988 brake handle geometry to the previous 1983 brake handle for comparison.

 

See attached PDF for comparisons

 

The leverage for the two handles is identical for practical purposes.

 

There is a .06 mm (.0025") difference. That is totally within the accuracy range considering that I drew these handles from a scanned image.

 

If some one wants to send me an RSV handle scan I will add it.

 

I don't think I will be getting an RSV parts bike anytime.

 

No fast parts on them anyways !!

 

Gary

[Thom]

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..

Jack , what did you do with those 2nd gen masters ? for some reason i have mk1 masters [ did not know it until i reread this thread ] and am used to them now but they are wearing out and would like something shinier .

Thom

[Condor]

Jack , what did you do with those 2nd gen masters ? for some reason i have mk1 masters [ did not know it until i reread this thread ] and am used to them now but they are wearing out and would like something shinier .

Thom

 

Never put them on the '83 Thom. Sold the bike before I did. But I still have another 5 1stGens to go so finding another bike for them isn't going to be much of a problem. If you're looking for a set the season is starting to heat up and I bet there'll be a few listed on Ebay this summer. Just ask about the sight glass before bidding and be picky on the condition. That's what I did.