[Jeff Savoie]

Update, as requested.

After my last posting, I noticed another issue that, to me, confirmed an incorrect adjustment. When using the cruise control if I touched the brake pedal the vehicle significantly slowed before (*and sometimes without) activating the brake light and cancelling the cruise control.

I finally took the car back to the shop in question, today. I’m pleased to report that the brake problem was cured and again I’m extremely grateful for the assistance you guys provided me. Having a good sensible position, and a resonable diagnosis, to negotiate from definitely helped.

Two weeks of driving with the brakes dragging didn’t do the pads or rotors any good, and I considered having the pads replaced… on their dime… but, considering that the rotors were only “good enough” (when the work was done), that I already have new ones for the back and will be buying them for the front, I didn’t feel like there was any real value in “punishing” the shop this way.

As an independent service technician he/we can’t know everything about a given brand of vehicle or job. We all learned something from this, and I find value in that (*at least equal to the cost of a few parts I have to buy eventually anyway).

The upside of all this is, I now have the confidence to install the rotors and pads myself, in no small part due to watching Eric’s Subaru brake job (and a couple other videos).

Krusty

[Jeff Savoie]

Update, as requested.

After my last posting, I noticed another issue that, to me, confirmed an incorrect adjustment. When using the cruise control if I touched the brake pedal the vehicle significantly slowed before (*and sometimes without) activating the brake light and cancelling the cruise control.

I finally took the car back to the shop in question, today. I’m pleased to report that the brake problem was cured and again I’m extremely grateful for the assistance you guys provided me. Having a good sensible position, and a resonable diagnosis, to negotiate from definitely helped.

Two weeks of driving with the brakes dragging didn’t do the pads or rotors any good, and I considered having the pads replaced… on their dime… but, considering that the rotors were only “good enough” (when the work was done), that I already have new ones for the back and will be buying them for the front, I didn’t feel like there was any real value in “punishing” the shop this way.

As an independent service technician he/we can’t know everything about a given brand of vehicle or job. We all learned something from this, and I find value in that (*at least equal to the cost of a few parts I have to buy eventually anyway).

The upside of all this is, I now have the confidence to install the rotors and pads myself, in no small part due to watching Eric’s Subaru brake job (and a couple other videos).

Krusty

[Jeff Savoie]

Barney,

Thanks for the reply.

Eric,

Thank you, too, for the reply.

By the way I found my way here, after watching you do the brakes and calipers on the ol’ Subaru (*after our car was already serviced). I’m a trained motorcycle tech and probably qualified to have done this work myself, but I don’t have a garage.
Boosters aren’t part of the motorcycle world so I had to do some research to understand it a little better.

While I can’t elaborate on why the booster failed, I can and will elaborate on why it was replaced.

About five days before I took the car in for service the brake pedal started the typical “pumping up” that accompanies a booster failure… the first press on the pedal I had brakes, the second time it got firmer and felt less powerful, the third press was fairly terrifying with nearly no power at all and a very stiff feel.

We live in the DC Metro area, traffic is pretty bad, and it got to where I refused to drive it in stop and go traffic (the last few days).
*You had to let all the way off the pedal for several seconds to keep the brakes fully functioning on the next press of the pedal.

So, the general consensus, through my research online, a stop at two of the local “big guys” repair shops, and a call my better half “had to” make to the dealership, was that the booster was indeed not functioning correctly.

When and if I take it back to the shop where I had the service performed, can you give me an idea of what I should be having them look at, and/or the kinds of possible “mistakes” that might lead to these kinds of symptoms?

Krusty

P.S. Yeah… hissing noise coming from the dash/firewall area.

[Jeff Savoie]

Barney,

Thanks for the reply.

Eric,

Thank you, too, for the reply.

By the way I found my way here, after watching you do the brakes and calipers on the ol’ Subaru (*after our car was already serviced). I’m a trained motorcycle tech and probably qualified to have done this work myself, but I don’t have a garage.
Boosters aren’t part of the motorcycle world so I had to do some research to understand it a little better.

While I can’t elaborate on why the booster failed, I can and will elaborate on why it was replaced.

About five days before I took the car in for service the brake pedal started the typical “pumping up” that accompanies a booster failure… the first press on the pedal I had brakes, the second time it got firmer and felt less powerful, the third press was fairly terrifying with nearly no power at all and a very stiff feel.

We live in the DC Metro area, traffic is pretty bad, and it got to where I refused to drive it in stop and go traffic (the last few days).
*You had to let all the way off the pedal for several seconds to keep the brakes fully functioning on the next press of the pedal.

So, the general consensus, through my research online, a stop at two of the local “big guys” repair shops, and a call my better half “had to” make to the dealership, was that the booster was indeed not functioning correctly.

When and if I take it back to the shop where I had the service performed, can you give me an idea of what I should be having them look at, and/or the kinds of possible “mistakes” that might lead to these kinds of symptoms?

Krusty

P.S. Yeah… hissing noise coming from the dash/firewall area.

[Jeff Savoie]

In general, most modern motorcycles work the following way;

On one end of the crankshaft is a gear. This gear, through reduction (the gear on the crankshaft is around ten times smaller than the gear on the outer basket), connects to the clutch outer (*known as the basket). This reduction means that an engine can “trade” RPM’s for torque.

A stacked set of multiple plates, some with a fiber coating (*not unlike an automotive clutch) and some that are steel, stacked in alternation, these transfer the engines rotation to the tranmission.

The fiber plates have dogs around the outside edges (*sort of like a huge square toothed gear) and these dogs correspond with gaps in the basket known as fingers. The steel plates have a set of gear teeth on the inside edge that mesh with a geared inner basket which in turn is connected to the transmissions main shaft.
A series of four to eight springs “squish” this stack of plates to engage the clutch (*spinning both parts of the basket together)…. a throwout or thrust bearing is connected to the clutch lever, via a cable or hydraulic cylinder, which pushes the inner basket away from the outer, allowing the plates to spin freely of one another.
Again, in most modern motorcycle engines, these plates are “wet” meaning they are lubricated with oil to keep them from overheating.
*That’s just part of why the correct type of oil used in a motorcycle engine is so important… way back when Mobil introduced graphite into oils, lots of us ruined the clutch plates in our bikes.

So… you pull the clutch lever in, the outer basket continues to spin with the engine, and the inner does not (*if the motorcycle is sitting, stopped).
When you let the lever out, the inner slips until fully engaged, which sets the transmission mainshaft in motion. The abilty to slip is what keeps you from stalling the engine, or launching violently forward.

I suppose now is a good time to stop and explain the mainshaft and countershaft relationship;
As I stated the mainshaft is connected to the inner basket (via a set of splines)… lying alongside it is a countershaft. Each of these shafts is splined to allow some of a stack of gears to slide sideways on them, fixed in rotation with the shaft. Other gears are allowed to spin freely around the shafts.

Here’s the key;
If a gear on one shaft spins freely, its mate is fixed to the other shaft. Also, if a gear spins freely the gear on either side of it (*on the same shaft) is fixed.
On the sides of some of the gears are dogs, and on the gear next to them the gear has slots in it, that correspond to the dogs… these dogs and slots are what make a specific set of gears, let’s say first gear, to both become fixed (*on the mainshaft and on the countershaft).

A series of “forks” ride in slots on the various gears, and a “drum” with a series of odd shaped slots in it move these forks back and forth sideways, engaging the gears in order…. first through fourth, fifth or sixth, depending on the bike. The shift lever is connected to the shift drum.

On one end of the countershaft, is a sprocket (*the countershaft sprocket) and again through reduction this sprocket turns the drive chain, connecting it to the sprocket on the rear wheel (*the drive sprocket) which turns the wheel.

*Conversely the countershaft can drive a belt pulley, or a drive shaft that is connected to the rear wheel…. but that’s another thread, in and of itself.
**As mentioned, in some (*generally older) bikes, the engine and tranmission are housed in separate cases… this is known as “pre-unit” construction, and then, rather than by direct geared contact the crankshaft is connected to the clutch via a belt of more usually a chain. In the case of pre-unit construction the transmission functions in the same manner as above, and connects to the rear wheel via chain, belt, or shaft.

I hope this helps more than it confuses y’all,

Krusty

[Jeff Savoie]

In general, most modern motorcycles work the following way;

On one end of the crankshaft is a gear. This gear, through reduction (the gear on the crankshaft is around ten times smaller than the gear on the outer basket), connects to the clutch outer (*known as the basket). This reduction means that an engine can “trade” RPM’s for torque.

A stacked set of multiple plates, some with a fiber coating (*not unlike an automotive clutch) and some that are steel, stacked in alternation, these transfer the engines rotation to the tranmission.

The fiber plates have dogs around the outside edges (*sort of like a huge square toothed gear) and these dogs correspond with gaps in the basket known as fingers. The steel plates have a set of gear teeth on the inside edge that mesh with a geared inner basket which in turn is connected to the transmissions main shaft.
A series of four to eight springs “squish” this stack of plates to engage the clutch (*spinning both parts of the basket together)…. a throwout or thrust bearing is connected to the clutch lever, via a cable or hydraulic cylinder, which pushes the inner basket away from the outer, allowing the plates to spin freely of one another.
Again, in most modern motorcycle engines, these plates are “wet” meaning they are lubricated with oil to keep them from overheating.
*That’s just part of why the correct type of oil used in a motorcycle engine is so important… way back when Mobil introduced graphite into oils, lots of us ruined the clutch plates in our bikes.

So… you pull the clutch lever in, the outer basket continues to spin with the engine, and the inner does not (*if the motorcycle is sitting, stopped).
When you let the lever out, the inner slips until fully engaged, which sets the transmission mainshaft in motion. The abilty to slip is what keeps you from stalling the engine, or launching violently forward.

I suppose now is a good time to stop and explain the mainshaft and countershaft relationship;
As I stated the mainshaft is connected to the inner basket (via a set of splines)… lying alongside it is a countershaft. Each of these shafts is splined to allow some of a stack of gears to slide sideways on them, fixed in rotation with the shaft. Other gears are allowed to spin freely around the shafts.

Here’s the key;
If a gear on one shaft spins freely, its mate is fixed to the other shaft. Also, if a gear spins freely the gear on either side of it (*on the same shaft) is fixed.
On the sides of some of the gears are dogs, and on the gear next to them the gear has slots in it, that correspond to the dogs… these dogs and slots are what make a specific set of gears, let’s say first gear, to both become fixed (*on the mainshaft and on the countershaft).

A series of “forks” ride in slots on the various gears, and a “drum” with a series of odd shaped slots in it move these forks back and forth sideways, engaging the gears in order…. first through fourth, fifth or sixth, depending on the bike. The shift lever is connected to the shift drum.

On one end of the countershaft, is a sprocket (*the countershaft sprocket) and again through reduction this sprocket turns the drive chain, connecting it to the sprocket on the rear wheel (*the drive sprocket) which turns the wheel.

*Conversely the countershaft can drive a belt pulley, or a drive shaft that is connected to the rear wheel…. but that’s another thread, in and of itself.
**As mentioned, in some (*generally older) bikes, the engine and tranmission are housed in separate cases… this is known as “pre-unit” construction, and then, rather than by direct geared contact the crankshaft is connected to the clutch via a belt of more usually a chain. In the case of pre-unit construction the transmission functions in the same manner as above, and connects to the rear wheel via chain, belt, or shaft.

I hope this helps more than it confuses y’all,

Krusty

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