Sleeving a Master Cyl Bore Where Parts are NLA

[Cdn850T5NT]

I recently put up a topic re the trapezoidal reservoir master cylinder (with the cylinder itself and the piston with seals both being NLA). This is from the Lario, T5, the LeMans IV, and the V35 Imola II. As shown in that post, seals ARE available (without the piston).  Well it appears that the master cylinder itself can be sleeved to brass, to hardened SS, or to type 304 SS.  Here are two references for reading-up on the process...

Note that one 'real important matter is drilling the holes in the sleeve once done. They have to be properly deburred. They also CANNOT be oversized lest the seals start to want to extrude thru the hole!  So, hardened, drawn SS tubing can be a prb due to hardness, difficulty in drilling small holes with a pin vise.

Also, the sleeve needs to be reamed to size.

See below:

Practical Machinist. https://www.practicalmachinist.com/vb/general/resleeving-motorcycle-master-cylinder-365558/

Karps Sleeving Svce. http://www.karpspb.com/sleeving.htm

Also try Whitepost Restorations

[Roebling3]

Long way from your home base, but. In the past I've witnessed these folks doing the impossible. 

Quality remanufacturing. 565 E. 37th Street Paterson, NJ 07513-1179.

Marion Szostak.  USA 973-523-8800. 

    Good fortune,  R3~

[Cdn850T5NT]

Thx R3... Me, I am well provided for... but let's add that firm onto the list. Anywhere in North America is NP for any of us, I would wager.

Cheers!

[Chuck in Indiana]

Crap.. I meant to put the info on the master cylinder in my Lario Stuff file.. didn't do it, and now I can't find it. Can you point me to the other thread?
TIA

[moto-uno]

 It may be easier to have a sleeve made from aluminum , that's what the original is made of , and a crap load easier to work with .  Peter

[Cdn850T5NT]

Crap.. I meant to put the info on the master cylinder in my Lario Stuff file.. didn't do it, and now I can't find it. Can you point me to the other thread?
TIA

Try here, at the very end:

https://wildguzzi.com/forum/index.php?topic=109205.0

Note that Gutsibits in the UK have info on the NLA Brembo kit (with piston) that suggests they may have an alternative. I suspect they modify a PS-12 piston for a round reservoir master... I will have to find that link later.

[Cdn850T5NT]

It may be easier to have a sleeve made from aluminum , that's what the original is made of , and a crap load easier to work with .  Peter

Peter, the thinness of the sleeve wall and the collapse resistance also 'hafta be considered. Aluminum may also have to be anodized for corr. resistance?

[moto-uno]

 If you change fluid every couple of years it should be pretty easy to keep that nasty H2O out of the cylinder , no ?
I must admit I'm not all that familiar with the master cylinder you're referring to , but they usually have more than enough
material to bore out for a 2mm thick sleeve with a mild press fit . I give these as an example because of a recent experience I've had
with a rear master cylinder for a 1976 Honda Gold Wing that I made an aluminum sleeve for and it's working now . It may
very well be a case of B.S luck . I'm sure any experienced machinist in the lower mainland could do much better , there's
only 2 holes to be accurately located and sized before pressing into place . Peter

[Cdn850T5NT]

Cool. Two year fluid changeouts... I agree. Surprised you drilled the holes beforehand. I'd have worried about the sleeve spiralling on its way in...

Cheers, John.

[Cdn850T5NT]

Oh, BTW, Peter re familiarity with that master cyl: I guess you built up a Series III T5 when you lived in central Canada... which would have had that trapezoidal master... but I guess you changed out all of the switchgear and that master to Suzuki components...? I forget the name of the fellow you did it for. He's on this board. Looked it up: Geoff in Almonte.

Or do I have my wires crossed here?

[Chuck in Indiana]

Try here, at the very end:

https://wildguzzi.com/forum/index.php?topic=109205.0

Note that Gutsibits in the UK have info on the NLA Brembo kit (with piston) that suggests they may have an alternative. I suspect they modify a PS-12 piston for a round reservoir master... I will have to find that link later.

Thanks for that..

[n3303j]

My T3 front and rear master cylinders (Brembo) had bores specified in metric units. Turns out converting the metric specs to SAE came out exact fractions of an inch. K&S makes thin wall seamless brass tubing for the hobbyist in fractional sizes. This tubing was perfect for relining the master cylinders on my T3.

Reamed cylinder 1/32 oversize. Cut tube to length and bonded it in with Loctite RC680. Drilled and demurred cross holes and called it done. That was 75,000 miles ago. It's worked so far.

[Cdn850T5NT]

That's excellent!

[moto-uno]

Oh, BTW, Peter re familiarity with that master cyl: I guess you built up a Series III T5 when you lived in central Canada... which would have had that trapezoidal master... but I guess you changed out all of the switchgear and that master to Suzuki components...? I forget the name of the fellow you did it for. He's on this board. Looked it up: Geoff in Almonte.

Or do I have my wires crossed here?

That would've been me . I had installed Yamaha switch gear and master cylinder on my Le Mans 2 even earlier and it's still there and working just fine !  Peter

[Cdn850T5NT]

Nominally called "PS-12"... I think bore is exactly 0.500"...

[Antietam Classic Cycle]

Nominally called "PS-12"... I think bore is exactly 0.500"...

The PS12 has a 12.84 mm piston, 12.84 mm = .5055"

[Cdn850T5NT]

Oh... Not 'gonna find a reamer of that size, I imagine... ???? Is that data from a trap. reservoir master or a round reservoir master?

[Chuck in Indiana]

Oh... Not 'gonna find a reamer of that size, I imagine... ???? Is that data from a trap. reservoir master or a round reservoir master?

Oh, yeah.. .005" over is common on reamers.

[Cdn850T5NT]

The PS12 has a 12.84 mm piston, 12.84 mm = .5055"

I found some contradictory info, albeit from a vendor, rather than the Mfr.  Is it possible that you viewed the rear master, at 15.84mm, and figured that the front Master was 12.84?

Please see these snaps...

And of course, there is a diametral clearance between the bore and the diameter of the piston.  I wonder what that is, and is it the same, for a range of nominal sizes of cylinder...??

[n3303j]

Please see these snaps...

1/2 inch and 5/8 inch respectively.

[Cdn850T5NT]

That makes a lot of sense... 0 500 and 0.625".  The 12.67mm piston size gives ~ 0.0012" of diametral difference between bore and piston. The 15.84mm piston gives similar diametral difference.

I conclude that the round reservoir piston diameter, stated at 12.7mm, is a round-up from the correct number of 12.67mm... simply as 12.7mm piston dia. would be size-on-size... and that would not work.

So in conclusion, that's cool: these master cylinder bores are Imperial sizes 😃. Easy peasy.

[geoff in almonte]

Oh, BTW, Peter re familiarity with that master cyl: I guess you built up a Series III T5 when you lived in central Canada... which would have had that trapezoidal master... but I guess you changed out all of the switchgear and that master to Suzuki components...? I forget the name of the fellow you did it for. He's on this board. Looked it up: Geoff in Almonte.

That would be me.  And it was Yamaha switch gear.  I last saw that bike (85 T5) at the National in NH a few years ago.  The silly thing had over 400k km on it and the owner said it was working great.

G

[Cdn850T5NT]

That's cool, Geoff!  400,000 km... (250,000 miles) - amazingly durable!

On another note, and related to the above thread:  folks might want to view this:  http://www.brakecylinder.com/index.htm

Those folks retired in 2013... but there is good instructive material in there, still, and it would appear that they do maintain their website.  They reference two of the outfits above that do sleeving.  They used to do sleeving to tempered brass, as mentioned in the graphic I attach.

[Furbo]

A newer, better MC is not a great expense.......why not just replace the silly thing and be done with it?

[Cdn850T5NT]

A newer, better MC is not a great expense.......why not just replace the silly thing and be done with it?

All of the switchgear, lever perches, throttle assembly, etc. are integral with the master... and for the LHS... switches and lever perch is integral.