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1Back to top Go down    Front brake lever travel on Thu Nov 29, 2018 5:50 am

audibob

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Hi All,

I can pull on my front brake lever a bit before the brakes are applied.

I do not mind it on the rear brake, but I prefer less free travel on the front.

What is the normal amount of travel on the front brake lever before it feels firm.

If I use one finger to pull the lever, I get 3mm between the lever and its housing.

Fairly firm pressure gives me a 4mm gap.

My first K100 was the same.

My system has been overhauled with a new master cylinder ( 13mm ) , braided lines, new fluid, new pads etc

and I have bled it several times.

I wander around the local bike shop now and again, and I have noticed some new bikes, even new ones, have

more travel on the brake lever than others.

Questions:

1. My new brake lever have an adjustment screw , If I use it to reduce the lever travel, I could get the brakes to

bind when the fluid cannot get back to the reservoir, so why the adjuster ?



2. Is my set up as it should be, or given the number of times I have bled the system,

could I still have air in it somewhere. I have tried all the usual "tricks "



3. Is there a possibility the ABS pumps are hiding something. I bleed the pump first , then the calipers.



4. Is there a way to force the ABS pumps to operate without riding the bike . I do not fancy a low speed

jaunt across a gravel path to get it to kick in, I recently dropped the bike whilst stationary,

do not want to do it again.

Bob

Thanks for any replies

Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

2Back to top Go down    Re: Front brake lever travel on Thu Nov 29, 2018 10:44 am

Laitch

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@audibob wrote:My new brake lever have an adjustment screw , If I use it to reduce the lever travel, I could get the brakes to bind when the fluid cannot get back to the reservoir, so why the adjuster ?
Please post a photo of this lever. Did it come with adjustment instructions?


__________________________________________________
1995 K75T 68,000 miles
    

3Back to top Go down    Re: Front brake lever travel on Thu Nov 29, 2018 10:57 am

duck

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I think he's referring to this one that has a set screw in it.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

4Back to top Go down    Front brake lever travel on Thu Nov 29, 2018 11:37 am

audibob

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Duck.

That is the lever I have.

Could the set screw be designed to be replaced if worn ?

There is no movement on the piston when the lever is fitted, it is a dead fit.

I presume on the k1100, the adjustment allows the position of the lever to be changed, without any action on

the piston.

Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

5Back to top Go down    Re: Front brake lever travel on Thu Nov 29, 2018 2:03 pm

Laitch

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@audibob wrote:I presume on the k1100, the adjustment allows the position of the lever to be changed, without any action on the piston.
There is a description of the lever adjustment procedure inthis post and the posts following it.


__________________________________________________
1995 K75T 68,000 miles
    

6Back to top Go down    Re: Front brake lever travel on Thu Nov 29, 2018 3:16 pm

duck

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@audibob wrote:Duck.

That is the lever I have.

Could the set screw be designed to be replaced if worn ?

There is no movement on the piston when the lever is fitted, it is a dead fit.

I presume on the k1100, the adjustment allows the position of the lever to be changed, without any action on

the piston.

Bob
I've adjusted that screw on my bikes before - but never very far in, just enough to get a better bite with less travel of the lever.

You're right. On the 4V bikes the adjustment is built into the middle of the lever and doesn't impact the lever interaction with the piston. (I really hate the 4V adjustable levers. I retrofited the old fixed version on my 94 K1100RS and much prefer it that way.)


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

7Back to top Go down    Front brake lever travel on Thu Nov 29, 2018 4:30 pm

audibob

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Thanks Duck.

I presume the set screw is for adjustment, otherwise the lever casting would be shaped so it sits against

the piston in its resting position.

But, it would take huge mileages to wear the set screw contact surface, even if you forgot to lubricate

it.

The link that Laitch posted gave me the impression that the k1100 has an adjustment to alter the position

on the piston, as well as being able to alter the lever starting position.

I know that too much adjustment could lock the brakes on..

I would prefer to find a tiny amount of air in the system, but given the number of times I have bled it,

I am not hopeful, unless I can force the abs pumps to kick in , then I will bleed it again and see.

If that fails, I will try a very small adjustment on the set screw

Brake lever " travel" is very subjective .

Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

8Back to top Go down    Re: Front brake lever travel on Thu Nov 29, 2018 4:41 pm

duck

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Where a lot of air can get trapped is in the "hump" in the ABS system that is between the modulator and the front calipers.

When I installed front SS lines on my K1100RS I took the calipers off and hung them by string from the garage rafters so that the air in the hump could rise to the bleed screws.

If you're just bleeding to flush the old fluid out with new fluid that shouldn't be necessary though.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S (K1 front end)
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

9Back to top Go down    Re: Front brake lever travel on Thu Nov 29, 2018 4:56 pm

Snod Blatter

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When we had a meetup for breakfast at the A46 cafe I had a try of everyone else's brake lever as I always thought there was surely something wrong with my system, all that travel and sod all braking.. But they were all the same! I blame the master cylinder, the lever is short and the piston too small.. But there's no way to change it so I just accept it now.


__________________________________________________
1989 K100RS SE ABS 8v VIN: 0149214
Others: 1.5 x Honda CBX250RS-E, '94 CB250, '95 TRX850, '16 Z250SL
http://justbikethings.blogspot.co.uk/
    

10Back to top Go down    Front brake lever travel on Thu Nov 29, 2018 5:26 pm

audibob

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I might try that Duck..

Snod,

I seem to remember trying someones clutch , but not the brake lever .

Does everyone who looks at bikes in the dealers try the brake and clutch levers .

or am I the only one..


bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

11Back to top Go down    Re: Front brake lever travel on Fri Nov 30, 2018 5:43 pm

Dai

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Count me in... affraid


__________________________________________________
'83 K100 upgraded to K100RS spec
Others...
'78 Moto Guzzi 850-T3, '79 Moto Guzzi 850-T3 California,'93 Moto Guzzi 1100ie California,
'03 Suzuki Blandit GSF600SK3 (NFS any more because wifey has claimed it)
    

12Back to top Go down    Re: Front brake lever travel on Fri Nov 30, 2018 8:54 pm

Two Wheels Better

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Moderator
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@audibob wrote:Does everyone who looks at bikes in the dealers try the brake and clutch levers .
bob
What, and not also twist the throttle and make playing card in the spokes noises with your lips like when riding your childhood bicycle?!


__________________________________________________

1987 K100RS, '93 Framed K11/K12 engine 'Big Block', '09 K1300GT, '07 K1200R, '04 R1150RT, '95 R100 Mystic, '77 R75/7.
Sniff...can you smell that? I think it might be bullsh*t.

    

13Back to top Go down    Front brake lever travel on Sat Dec 01, 2018 5:21 am

audibob

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Platinum member
I Should have fitted a playing card on the back wheel to drown out my old FD bearing drone.... lol!


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

14Back to top Go down    Front brake lever travel on Wed Dec 12, 2018 12:51 pm

audibob

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Platinum member
I tried to reduce the lever free travel by screwing the adjuster set screw in slightly, but I found that the braking

action became a little notchy.

The set screw was backed off, so just coming into contact with the piston in its resting position,

and the brake action was smooth again.

I have decided to accept the lever travel, whether I still have a tiny bit of air in the system,

or this is how it is.

The brakes are very smooth and sharp, so I am happy with that.

Bob


__________________________________________________
Yamaha 90
Honda CD 175
Honda CB 360
Triumph T 140V Bonneville
Triumph T150 Trident
Honda CB750 F1
Cz 175
Yamaha XS 750
R 100/7
R 80
K100 LT
K100 LT current bike
    

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