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Discussion Starter #1
So I have flushed and changed the fluid in the front brake and bled the lines. However my front brake still feels a little soft. Which is why I started this in the first place.

It stops fine enough. Just feels like it should be firmer. I've had the bike 2 years now so I'm not sure if it's worse than it was two years ago or not. Pads have about 1000 miles on them.

Is the soft front brake somewhat normal on this model? And maybe I'm chasing a problem that doesn't exist or do I have a problem?

When I pull the brake back I can get it within one inch or so of the grip at setting #1.
 

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"soft" and "firm" aren't objective qualities regarding brake since what is "soft" for one rider might well be "firm" for another, unless there is something else involved such as if the brake lever sinks all the way to the handgrip or it is "squishy." The front brake on my 900 is reasonably firm for me and that hasn't changed since I got the bike new in '07. I change the fluid and flush the system each two years, per the OM.
 

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So I have flushed and changed the fluid in the front brake and bled the lines. However my front brake still feels a little soft. Which is why I started this in the first place.

It stops fine enough. Just feels like it should be firmer. I've had the bike 2 years now so I'm not sure if it's worse than it was two years ago or not. Pads have about 1000 miles on them.

Is the soft front brake somewhat normal on this model? And maybe I'm chasing a problem that doesn't exist or do I have a problem?

When I pull the brake back I can get it within one inch or so of the grip at setting #1.
Kawi recomends replacing the brake lines every 4 years. The rubber lines can stretch and make the brakes feel spongy. Perhaps consider upgrade to Stainless steel braided lines. They should be good for a longer period.

WB
 

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Discussion Starter #4
"soft" and "firm" aren't objective qualities regarding brake since what is "soft" for one rider might well be "firm" for another, unless there is something else involved such as if the brake lever sinks all the way to the handgrip or it is "squishy." The front brake on my 900 is reasonably firm for me and that hasn't changed since I got the bike new in '07. I change the fluid and flush the system each two years, per the OM.
I get what you are saying, however by soft, as stated in my op, I mean I can pull the handle back within one inch of the grip. I don't remember it always being like that but maybe it was. I was hoping some 900 owners would chime in on the play in the front brake lever.
 

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Discussion Starter #5
Kawi recomends replacing the brake lines every 4 years. The rubber lines can stretch and make the brakes feel spongy. Perhaps consider upgrade to Stainless steel braided lines. They should be good for a longer period.

WB
I mean they are 9 years old so that is possible I guess. Would you be able to measure the expansion of the brake line if that were happening?
 

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The brake lines on my '07 VN 900 are nine years old and show no apparent sign of deterioration. It seems to me that Kawi's recommendation of replacement each four years is excessively pessimistic about line life. The front hydraulic brake line on my Yamaha XS 650D was 30 years old and was still good, even though the bike often was parked in strong sunlight during daylight as I used it to commute to and from work. If one replaces brake flexi brake lines with metallic lines there still will need to be flexible hoses employed at some point to allow for suspension movements.
 

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Really only 3 things cause this problem. Old fluid, air in the system, or bad seals/hoses. Being that you just flushed the fluid we can rule that out, the seals and hoses tend to outlast most interchange intervals by 3 fold so we will leave that for a bit. That leaves air, most likely caught in the master cylinder

We run into a similar problem fairly regularly on our training bikes.....and my Father in law's V-rod. Before buying any parts consider unbolting the master cylinder from the handlebars (leave the line hooked up) and pump the lever while holding the MC at a steeper angle. The angle needs to be sufficient to allow any trapped air to move either up to the reservoir or into the hose. On our training bikes I just slide it down the bars toward the risers, usually solves the problem in 3-5 minutes.

Alternatively you could have bad seals in the MC or bad hoses. If you squeeze the lever in all the way and hold it will it move closer to the bar the longer you squeeze it?
 

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The brake lines on my '07 VN 900 are nine years old and show no apparent sign of deterioration. It seems to me that Kawi's recommendation of replacement each four years is excessively pessimistic about line life. The front hydraulic brake line on my Yamaha XS 650D was 30 years old and was still good, even though the bike often was parked in strong sunlight during daylight as I used it to commute to and from work. If one replaces brake flexi brake lines with metallic lines there still will need to be flexible hoses employed at some point to allow for suspension movements.
Just because a nine year old, or 30 year old brake line holds fluid and pressure doesn't mean it is still as good as it was brand new. Synthetic rubber OEM brake hoses are some of the cheapest construction hoses made (I have been an engineer in hydraulic hose for 22 years). The outside may look ok, but the inner tube swells/softens over time, and contributes to the spongy brake feel. I would never spend one penny on original old style brake hose. Stainless steel braided hose is made around a Teflon inner tube which is VERY durable and does not degrade over time like the stock hose. Replace the stock hose with the S/S braided hose and you'll get much more firm response on the brake.
 

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Just because a nine year old, or 30 year old brake line holds fluid and pressure doesn't mean it is still as good as it was brand new. Synthetic rubber OEM brake hoses are some of the cheapest construction hoses made (I have been an engineer in hydraulic hose for 22 years). The outside may look ok, but the inner tube swells/softens over time, and contributes to the spongy brake feel. I would never spend one penny on original old style brake hose. Stainless steel braided hose is made around a Teflon inner tube which is VERY durable and does not degrade over time like the stock hose. Replace the stock hose with the S/S braided hose and you'll get much more firm response on the brake.
Obviously what one does is a personal choice. My experience in about 50 years of riding is that I've never had to replace an OEM hydraulic brake line and I've not had any brake problems, and that includes no feeling that the braking has become softer because of brake line deterioration. Bleeding brakes hasn't shown signs of deterioration, either, such as bits of brake line in the bled fluid. None of those in my riding group has reported replacing their hydraulic brake lines either unless going to apes and some have been riding about as long as I have. If a brake line shows signs of deterioration obviously it should be replaced, but unless that occurs it isn't necessary unless one otherwise wishes to do so.
 

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I get what you are saying, however by soft, as stated in my op, I mean I can pull the handle back within one inch of the grip. I don't remember it always being like that but maybe it was. I was hoping some 900 owners would chime in on the play in the front brake lever.
When I bought my 900 used I first thought the brakes were too soft. Turned out the person who had owned it before me had adjusted the lever way too close to the grip for my liking. I adjusted it farther out and have been happy ever since.

If you are bothered by how close to the grip it comes, you might try the little adjustment wheel at the front brake lever.

Sometimes the simplest solutions are the best.
 

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try adjusting the brake lever to 3 or 4 and see how it feels and fits your hand. another trick is to open the top to the brake reservoir and tie your brake lever back and leave it overnight. if there is any small air bubbles they will work their way out.
 

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True, personal preference is part of it. My 43+ years of riding include everything from drum brakes (front and rear) on late 60's Yamahas to typical early disc brakes of the 70's to my 2007 BMW (which comes with S/S braided hose stock). My 94 BMW R1100RS produced much better brake feel when I changed the brake hoses to S/S braided style. My experience also in 23 years of teaching motorcycle safety courses, that when it comes to braking skills and practice, very few riders ever use their brakes to the full capability of the bike, that is until the panic moment comes and then all sorts of bad things happen. In practicing braking skills I have found that even on my BMWs I can almost get the lever back to grip during high effort braking, even with S/S braided hoses.

Keep in mind too, that many riders of many years, may not have ever gotten past 20,000 miles on one bike, to the point of repeated brake system maintenance. I have been riding my 94 BMW since Oct and am near 190,000 miles on it now, so brake maintenance and updates are part of those miles. Average annual mileage around the country and cycle styles is about 2500 miles, so even a bike ridden by one person for ten years will only have 12,000 to 15,000 miles. In that time the brake system may never get new pads, may never have the brake fluid changed. On the many many bikes I have worked on, I have seen many with deep brown or almost black brake fluid in the reservoir, and severely corroded brake systems (internally). Dark ineffective brake fluid is usually contaminated by water, but also largely by synthetic rubber brake hose inner tubes softening/swelling/breaking down. Its not a matter of IF, they ALL break down and contaminate the brake fluid, and produce a spongy brake response. Most riders never realize the difference because they "calibrate" themselves to the way the brakes feel over miles and years. Unless you have experienced the difference directly by changing over the brake fluid , or changing out the brake hoses you may not even realize the much better braking feel and control when the "spongy" effect is gone.

So, yes, it is the rider's choice, and old, contaminated brake systems with spongy brake hoses do still stop the bike (but with a lot more effort on the part of the rider). But the best upgrade for a brake system on a bike with synthetic rubber brake hoses is to change out the OEM hoses to S/S braided brake hoses.
 

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If you think you might have air in the brake line, a trick I have used is squeeze the brake lever and hold it with a zip tie. It doesnt have to be real hard. Leave it "squeezed" overnight. This will allow any trapped air to rise to the reservoir.
 

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Discussion Starter #14
Really only 3 things cause this problem. Old fluid, air in the system, or bad seals/hoses. Being that you just flushed the fluid we can rule that out, the seals and hoses tend to outlast most interchange intervals by 3 fold so we will leave that for a bit. That leaves air, most likely caught in the master cylinder

We run into a similar problem fairly regularly on our training bikes.....and my Father in law's V-rod. Before buying any parts consider unbolting the master cylinder from the handlebars (leave the line hooked up) and pump the lever while holding the MC at a steeper angle. The angle needs to be sufficient to allow any trapped air to move either up to the reservoir or into the hose. On our training bikes I just slide it down the bars toward the risers, usually solves the problem in 3-5 minutes.

Alternatively you could have bad seals in the MC or bad hoses. If you squeeze the lever in all the way and hold it will it move closer to the bar the longer you squeeze it?
This is a great tip. I will try it tonight. No. The lever does not move closer to the bar the longer I squeeze it.
 

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Discussion Starter #15
If you think you might have air in the brake line, a trick I have used is squeeze the brake lever and hold it with a zip tie. It doesnt have to be real hard. Leave it "squeezed" overnight. This will allow any trapped air to rise to the reservoir.
I did this on two separate nights. No change.
 

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Discussion Starter #16
We run into a similar problem fairly regularly on our training bikes.....and my Father in law's V-rod. Before buying any parts consider unbolting the master cylinder from the handlebars (leave the line hooked up) and pump the lever while holding the MC at a steeper angle. The angle needs to be sufficient to allow any trapped air to move either up to the reservoir or into the hose. On our training bikes I just slide it down the bars toward the risers, usually solves the problem in 3-5 minutes.
This worked. Thanks for the tip!
 

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Often times the most simple solution is the one most overlooked. Glad it worked and you got the firm lever back.
 
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