Brake Lever Swap Question

[droo]

39 minutes ago, DieselnDust said:

car serviced every 15000km religiously - brakes serviced= brakes don't fail = great brakes

bike serviced and jet washed after every ride - brakes not serviced = brakes fail = crappy brakes

 

????

90% of the time the problem is between the saddle and the bars...

[DieselnDust]

11 minutes ago, droo said:

90% of the time the problem is between the saddle and the bars...

90%… 

Im certain it’s closer to 100 than 90????

[Hairy]

38 minutes ago, droo said:

90% of the time the problem is between the saddle and the bars...

WHAT .,.. the top tube causing chaos!?!?!

[DieselnDust]

50 minutes ago, Hairy said:

WHAT .,.. the top tube causing chaos!?!?!

Only if it’s a canyon

[Mountain Bru]

4 hours ago, droo said:

Shimano levers and calipers all work together. Swap away. And as a bonus the lever sets are cheap as chips, if you can find them.

 

(Assuming you're talking about swapping complete lever assemblies and not just the blades, cos that probably won't work.)

When you say that they all work together, do you mean same oil and fittings, or same lever throw and actuation etc. 

I would assume that it's not the same, and that the same lever throw would cause different pressure in the hoses, and therefore different travel on the pistons?

[Mars1967]

3 hours ago, DieselnDust said:

This has nothing to do with the compatibility of the mating parts.

Both use mineral oil and Shimano fittings.

The only issue will be the lever throw. Does the lever master cyclinder of the BL 445 match that of the Deore BL6100? From what I can gather they are similar and therefore should not represent a problem to swaparoo.

I was working on the assumption (based on what is provided in the post) that he is referring to swapping the levers only and not the entire brake lever master cylinder assembly. That makes a huge difference.

Edited September 13, 2021 by Mars1967

[droo]

52 minutes ago, Mountain Bru said:

When you say that they all work together, do you mean same oil and fittings, or same lever throw and actuation etc. 

I would assume that it's not the same, and that the same lever throw would cause different pressure in the hoses, and therefore different travel on the pistons?

Lever feel will be very different - but this is good, those 445 levers are about as long as Hobie tillers and feel like utter poo.

 

As far as I've seen the caliper pistons on all Shimano brakes have the same surface area, which means they all need the same amount of fluid to work properly. This means that you can use any Shimano lever (and as Jewbacca said, even Magura work).

[Headshot]

Nope, I think you'll find brakes on cars work for tens of thousands of km without the need to worry about bleeding them even once a year. Brake services don't happen every oil service/bleed and usually only when the pads require changing. 

 

[Brett CT]

1 hour ago, Mars1967 said:

I was working on the assumption (based on what is provided in the post) that he is referring to swapping the levers only and not the entire brake lever master cylinder assembly. That makes a huge difference.

I would like to replace the entire master cylinder assembly. I am working under the assumption that as long as the brake lever assembly that I swap in is also designed for a 2 pot caliper that the volumes of the pistons for both the lever and caliper are similar and should therefore be able to be swapped without issue. This seems to be the general consensus from the Hub.

[Jehosefat]

41 minutes ago, Brett CT said:

I would like to replace the entire master cylinder assembly. I am working under the assumption that as long as the brake lever assembly that I swap in is also designed for a 2 pot caliper that the volumes of the pistons for both the lever and caliper are similar and should therefore be able to be swapped without issue. This seems to be the general consensus from the Hub.

The 2 vs 4 pot doesn't matter either. As far as I am aware the Shimano 2 and 4 pot calipers use the same levers (at least Deore, SLX and XT do, not sure about Saint).

[DieselnDust]

46 minutes ago, Brett CT said:

I would like to replace the entire master cylinder assembly. I am working under the assumption that as long as the brake lever assembly that I swap in is also designed for a 2 pot caliper that the volumes of the pistons for both the lever and caliper are similar and should therefore be able to be swapped without issue. This seems to be the general consensus from the Hub.

and designed to use the same type of brake fluid i.e. mineral oil in your case

[droo]

1 hour ago, Jehosefat said:

The 2 vs 4 pot doesn't matter either. As far as I am aware the Shimano 2 and 4 pot calipers use the same levers (at least Deore, SLX and XT do, not sure about Saint).

Correct. The surface area of the 4 pistons combined is the same as the 2 on the 2 pots.

[Rolf Hansen]

7 hours ago, Hairy said:

WHAT .,.. the top tube causing chaos!?!?!

What he meant was that the problem is usually the nut that connects the handlebars to the seat. 

[Hairy]

1 minute ago, Rolf Hansen said:

What he meant was that the problem is usually the nut that connects the handlebars to the seat. 

Or a bit of RTFM