gl1100 front brake master cylinder upgrade?

[Smokey66]

NOT TRUE! Has nothing to do with how much fluid the resivour holds:On my custom bikes I`ve used a master cyl. from a sport bike that came with a remote resivour which I REMOVED and replaced with a two inch piece of clear hose with a plug in the top.That thing holds about a tablespoon of fluid.When the system is full its full and it don`t matter if the thing holds a gallon its not going to change anything!Piston dia in the cyl is important cause its all about how much fluid the piston can push,or better said how much volume it can displace.And that piston don`t care if one or ten calipers are attached to it.Check the piston size on both systems;there the same.

 

[slabghost]

NOT TRUE! Has nothing to do with how much fluid the resivour holds:On my custom bikes I`ve used a master cyl. from a sport bike that came with a remote resivour which I REMOVED and replaced with a two inch piece of clear hose with a plug in the top.That thing holds about a tablespoon of fluid.When the system is full its full and it don`t matter if the thing holds a gallon its not going to change anything!Piston dia in the cyl is important cause its all about how much fluid the piston can push,or better said how much volume it can displace.And that piston don`t care if one or ten calipers are attached to it.Check the piston size on both systems;there the same.

Read again. Displace means push more fluid to supply two calipers. I agree the the reservoir capacity has little to do with function.

 

[dan filipi]

I've never actually tried it but pushing 2 calipers must have to require more fluid than pushing 1 since the volume of space is doubled, no?

 

[slabghost]

Correct! Number of pistons per calipers is also a factor. Some of the newer calipers can be had with 3 or 4 pistons each. Thus requiring more fluid per pump of the master to actuate.

 

[Smokey66]

Look up the piston sizes of bikes with 1,2,4,and 6 piston calipers.My old fz750 has 2, 2 piston calipers and my fzr 750 has 2, 6 piston calipers,but the piston size in both masters is 5/8".Most newer bikes have 14 mm pistons,real close to 5/8)some serious race stuff(Nissan makes aftermarket units) has 20/22 mm piston size.Like I said,I`ve done this many times and even the German TÜV approved it(here every modification has to be tested and approved by an Mechanical Engineer) .

 

[Smokey66]

OK folks this just wont let me be either...heres some info I found concerning this subject;apparently piston dia is not as important as piston STROKE and LEVER/PEDAL RATIO!
https://www.outlawdiscbrakes.com/faq.html
https://www.hotrodders.com/forum/master- ... 64432.html
this might help clear things up

 

[joedrum]

thanks smokey i didnt get a lot out of it the first time through but im going to sit on it awhile and read it again later ....thanks :mrgreen:

 

[thewhiterhino]

A larger piston size on the master cyl will increase the force required to apply the brakes while the smaller piston in the master cyl will require less force to apply if the mechanical linkage is the same. The mechanical linkages that are involved in the master cylinders would be adjusted by design to yield a target PSI of pressure. The piston area of the calipers can be varied according to the desired braking force at the designed PSI applied. Larger caliper piston more brake pad pressure, smaller caliper piston less brake pad pressure.
My 83 Aspy has linked brakes and the right caliper on the front has much smaller pistons than the left and are the same size as the rear caliper. I know that I can apply much more pressure with my foot than my hand and I suspect that is why the differences in caliper piston sizes.
I am still considering unlinking the system but would need a right caliper with the same size pistons as the left.
:salute:

 

[slabghost]

A larger piston size on the master cyl will increase the force required to apply the brakes while the smaller piston in the master cyl will require less force to apply if the mechanical linkage is the same. The mechanical linkages that are involved in the master cylinders would be adjusted by design to yield a target PSI of pressure. The piston area of the calipers can be varied according to the desired braking force at the designed PSI applied. Larger caliper piston more brake pad pressure, smaller caliper piston less brake pad pressure.
My 83 Aspy has linked brakes and the right caliper on the front has much smaller pistons than the left and are the same size as the rear caliper. I know that I can apply much more pressure with my foot than my hand and I suspect that is why the differences in caliper piston sizes.
I am still considering unlinking the system but would need a right caliper with the same size pistons as the left.
:salute:

Correct or one would lock first.

 

[jdegase]

very good info guys... thanks for all the input.
I dont mind the linked break system so far, so I decided to stay with the stock master and just replace the tank...
next I will replace the lines with stainless and possibly paint and rebuild the calipers in the spring .

 

[joedrum]

the 83 i got jim totaly surprised me .....i live around a lot of gravel roads and was sure that the linked brake system was going to be a problem .....butit seems that it was well behave on gravel roads around here .....i didnt ride it a whole bunch before i decided it was a winter project to get right and started riding the 82 which gets you in trouble easier.....ive been thinking jim that maybe on my mongruel project of hooking the link brake system backwards as to to have the two brakes hooked up to the hand brake with a master cylinder from a two disc setup ....as i might go with forward controls on it that has been in the making for yrs in my mind

but anyway i cant find any faut to the system as i use it so far ....good on gravel around here :mrgreen:

 

[scdmarx]

i cant find any faut to the system as i use it so far ....good on gravel around here :mrgreen:

I don't have any problem with mine either. The linked idea seems to work pretty good, I think. Guys who are dumping their bikes and blame the linked system makes me wonder if maybe something else is wrong. Maybe there is something to do with front pad contamination, or something causing the front to lock up?????
All I know is I'm starting to really like the linked system. The only problem I have found is difficulty useing the rear brake and clutch technique for slow riding and u turns in parking lots and the slow moving line of traffic at stop sign intersections. (I forget what it's called)