So long Mac.

Discuss all things 1970 & later Airheads right here.
Major Softie
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Re: So long Mac.

Post by Major Softie »

I really like the BT45's - have them on the K and the little Honda V500 Ascot - but I don't buy them for mileage. For feel, they're great.
MS - out
ME 109
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Re: So long Mac.

Post by ME 109 »

Chuey, My RS doesn't have much clearance using a 110. A 120 would fit at a squeeze, and might require a longer top hat to give satisfactory swing arm clearance.
What size tyre did you buy?
I would expect mileages much better than 5 and 6 thousand k's can be achieved with a bt45 rear.
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dougie
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Re: So long Mac.

Post by dougie »

I recently mounted BT45's, and it is my understanding that the rear has the "dual compound".
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.
John Falconer
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Joined: Tue Aug 03, 2010 11:34 am

Re: So long Mac.

Post by John Falconer »

I used the Mac50's exclusively for several years ... then they became too difficult to find and I switched to the Avon Roadriders. They're available in the correct sizes and actually have some attributes that are a step ahead from the Mac50 (for example, no continuous center groove means less tendency to track rain grooves).

John Falconer
ME 109
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Re: So long Mac.

Post by ME 109 »

I had a pirelli sport demon fitted today. A good deal cheaper than a Mac50.
$165 fitted for the pirelli compared to $205 for the mac.
It will be interesting to see how it performs/lasts.

Bought a handle bar master cylinder from motobins, cost me $168 compared to $350 list price from munich cycles.
I'm happy with that.
And happy that I no longer have a leaking master cylinder.
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SteveD
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Re: So long Mac.

Post by SteveD »

ME 109 wrote: Bought a handle bar master cylinder from motobins, cost me $168 compared to $350 list price from munich cycles.
I'm happy with that.
Jeff, 13, 14 or 15mm?

Oh look! An edit button! Bewdy.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
ME 109
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Re: So long Mac.

Post by ME 109 »

15mm Steve. I thought about finding a s/hand unit but after seeing the price of a brand new one from motobins, I thought it was the way to go.
The mc housing was really beyond restoring due to pitting in the bore and corrosion elsewhere, so a 'kit' was not the solution.
Time to find a good s/hand unit was against me also, as the leak became substantial.
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George Ryals
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Re: So long Mac.

Post by George Ryals »

Save the pitted one and have it bored and sleeved to 14 mm. You will get a little more lever travel, better feel and more power with the same hand squeeze.
Smile it's contagious!
'74 R90S, '67 /2 Conv w/sc, '66 R50/2
'74 Harley FXE, '72 Harley FLH w/HD sc
'69 BSA 441 Victor Special, '74 R90/6 Basket case
'85 R80RT wreck for parts
ME 109
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Re: So long Mac.

Post by ME 109 »

Interesting modification George.
I noticed the main difference between the bore sizes (13, 14, 15, and 16) was different types of piston/brake lever configurations.
What other mods are needed to be compatible to the 15mm set up?
My old mc has corrosion around where the circlip seats. Still serviceable but perhaps not worth the effort/expense in this case.
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George Ryals
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Re: So long Mac.

Post by George Ryals »

The main difference is that the smaller MC diameters give higher line pressure with the same hand pressure than the larger diameters. The lever travel is a little longer with a smaller dia. to get the same caliper piston travel.

If you had a 16 mm mc before, you will notice better braking with a 15mm.....less hand pressure for the same braking as with the 15 mm mc. There are no equipment mods needed to change mc sizes other than changing the mc.

I think when the mc is sleeved, the sleeve wall thickness is eonugh for a new circlip groove.
Smile it's contagious!
'74 R90S, '67 /2 Conv w/sc, '66 R50/2
'74 Harley FXE, '72 Harley FLH w/HD sc
'69 BSA 441 Victor Special, '74 R90/6 Basket case
'85 R80RT wreck for parts
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