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I have a set of SS brake lines, including the extended upper brake line for my '09 ABS Wee. My question is, is there any special procedure for flushing and bleeding the brakes on the ABS Wee. I have a shop manual, but it's not for the ABS version. Thanks.
 

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FORUM GODFATHER.....R.I.P. PAT
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The manual just refers to the pre 2007 page on brake bleeding. Some have said getting the front wheel up higher helps get air out of the lines to the pump but the manual say nothing about it.
 

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I found this post by searching brake line bleeding - glad I found it.

I just installed a set of Gaffer SS brake lines on the front end of my 2007 DL650. The kit I have is the one using two separate lines, with a double banjo bolt at the master cylinder. Everything went together fine, in the order it is suppose to.

I removed the master cyl cap to make it easier to add fluid, as I fed and bled two new (empty) lines. I started by opening the bleeder on the right-hand wheel cylinder. When I started pumping the brake lever, there was an initial push of fluid coming out of the clear drain line I attached. Then, it stopped and the system never built any pressure and the fluid level did not drop.

I closed the bleeder screw and moved to the left-hand wheel cylinder. I hooked up my clear drain line and opened the bleeder screw. Same thing happened - an initial push of fluid, and then nothing more. I closed that bleeder screw (both closed now) and pumped the brake lever (a lot) to see if any pressure would build. It doesn't.

I see that there's a bleeder screw on the front master cylinder. I haven't done anything with that yet, thinking instead I'd post this rather than make a mistake. What is the purpose of that bleed screw? Do I need to open that to help fill the empty lines? I think the fluid that came out of the wheel cylinders was old fluid already in them, and that air created by pumping the brake lever, pushed that small amount of fluid... not new fluid in the new lines.

BTW, I have installed and bled a lot of brakes on cars, bikes, go-karts, etc. This is the first time I have experienced "nothing" happening when pumping the master cylinder.

Thanks for any help you can provide.
 

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I found another thread on this topic and it seems I need to be more patient. It takes a long time to replace the air in a new line with fluid, just by pumping the brake lever. I saw a couple tips about opening the bleeders and tieing back the brake lever to create an open-ended system that will fill by gravity and atmospheric pressure. Okaaaaayyyyyy, if that's what it takes.

I'm still interested to know more about the bleeder screw on the master cylinder. And... I'm still open to suggestions, confirmations, condolences, congratulations and other forms or positive communications with humans... and dogs.

Cheers!
 

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FORUM GODFATHER.....R.I.P. PAT
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Are you talking about a bleed nipple on an aftermarket banjo bolt? The stock master cylinder doesn't have a bleeder screw.
 

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You are absolutely correct, the master cylinder does NOT have a bleeder, nor does the banjo bolt.

When the brakes didn't pump up pressure and bleed as expected, went back to the instructions provided with the brake line kit. The instructions said the master cylinder had a bleeder valve. Being very late, and already tired from a long day, I didn't do a full visual inspection.

I felt around the master cylinder and thought I found it. What I found was part of the brake light switch. My tired mind allowed me to believe the instructions and I was convinced I had found it.

I looked at it again after reading your reply. Duh! I had already talked to a couple guys today and they gave a few suggestions, which I'll try next. Mainly, to remove the banjo bolts at the wheel cylinders and pump fluid through the lines. Once they start passing brake fluid, reinstall them and start filling and bleeding the wheel cylinders.

Thanks for the reply. Pardon my whacky question - I'm normally much better informed when asking for assistance.
 

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a few things to remember

This thread is timely, as I've done this three times this month. I'll add a few things I've learned about refilling the braking systems on this bike:

  • The rear is tricky because the highest point in the system is the loop of hose near the exhaust. What worked for me was velocity: get fluid moving quickly by using lots of lever pressure.
  • For the front, the key is patience. It can take a long time for air to bubble up to the master cylinder. Start by letting fluid drain from the MC to the calipers by gravity; then bleed as normal. Once air stops coming out, stop pouring more fluid in; you're just wasting it (ask the man who has gone through a gallon of DOT 4 this month :headbang:). Let it sit for a couple of hours, with the bike on the side stand and the wheel full lock left (so the MC is the highest point in the system); work the lever slowly every few minutes. Pressure will eventually return.
  • The front was at about 80%, but still not quite right, after I was done. The final step to get the front to firm up to where it should be is to clamp the lever overnight (I used a velcro strap), with the wheel full lock left, to get it to burp. That did the trick for me.
  • I have and used a Mity Vac, but I don't think it was very useful. I wouldn't bother with it next time.
Hope this helps. For the record, mine is not an ABS model; YMMV.
 

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Bleeding the master cylinder is the tedious part, as dtalk describes. You can hold a rag under the banjo bolt, squeeze the lever, slightly loosen the banjo, bleed bubbles out, tighten, release the lever, add fluid if necessary, do it again and again and again. Air bubbles in the fluid rise, so give them a place to rise to and escape. Strapping the lever down overnight works.
 

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[*]The front was at about 80%, but still not quite right, after I was done. The final step to get the front to firm up to where it should be is to clamp the lever overnight (I used a velcro strap), with the wheel full lock left, to get it to burp. That did the trick for me.
Well, crap. It was great this morning, but as soon as it got warm, I was right back where I was yesterday. I think that clearly implicates some air somewhere, which expanded as the temp rose. I'll clamp it again tonight.
 

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That didn't work. Again, it was much better in the morning, but softened up as it warmed.

How is clamping the lever overnight expected to help, anyway? I can't understand how merely compressing the fluid will change the fact that air can't (or shouldn't be able to) migrate upward beyond the primary cup, unless the cup is worn and in need of replacement.

I have tried bleeding the MC at the banjo bolt, with the wheel full lock right to ensure that the banjo was the highest point in the system. It's slightly better, but still feels a good deal softer than I think it should. In any case, the fact that I get more lever travel with the same amount of hand pressure when the system is warm seems to indicate that there's still an air bubble somewhere.

It would be great if there were some objective measure of success in this operation. It's frustrating to have only subjective "feel" to go by. I even stopped by a dealer on my lunch break to compare the lever feel of a new Strom, and it does offer decidedly more resistance than mine (with lever adjusters set to 1 in both cases).

How do shops do this? Do they use pressure bleeders?
 

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I wonder if it might be worthwhile to unmount the reservoir from the handlebar and fix it temporarily so that the MC is nearly vertical.

The threaded part of the bore is not concentric with the smooth part, and is offset toward the bottom of the bore, leaving a shoulder at the top -- it seems entirely possible for a small bubble to be trapped there at the top of the bore. Mounting the MC near-vertical (just enough off vertical so that the hose doesn't rise above the height of the fitting) might fix that.

Again, I'd love to hear how well-equipped shops deal with this ... it's definitely the least fun of any maintenance chore that I've done. :headbang:
 

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I've always said that one of my favorite tools is the vacume brake bleeder. Around $50, no waiting for hours on end, and the bleed is a 15 minute job after installing new lines or master. When used correctly it's a one shot deal
 

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I've always said that one of my favorite tools is the vacume brake bleeder. Around $50, no waiting for hours on end, and the bleed is a 15 minute job after installing new lines or master. When used correctly it's a one shot deal
I've already sucked a pint of fluid through both calipers using a Mity Vac. I don't think that's going to fix my problem, unless I'm doing something wrong.
 

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Use teflon tape on the bleeder screw threads

When using the Mity Vac, first make sure that no air passes between the threads of the loosened bleeder screw on the caliper. If air leaks through, you will just be sucking air through these threads when using the Mity Vac. If air does leak through, you should wrap a few layers of teflon tape around the threads of the bleeder screw and then re-install on the caliper.

This worked for me.
 

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I've already sucked a pint of fluid through both calipers using a Mity Vac. I don't think that's going to fix my problem, unless I'm doing something wrong.
Unusual. Is your fluid from a new, unopened container? Correct DOT #? It's entirely possible your master cylinder is bad but I would first double check that all your line fittings are tight and correctly threaded. Was a new banjo installed? If so , were new washers used and in the correct order? Heat related fade away is usually due to contaminated fluid or a bad master. Interesting scenario you have here considering you have done this proceedure before, presumably your master was fine before the new lines, and you have flushed enough fluid through to remove any contaminats
 

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Unusual. Is your fluid from a new, unopened container? Correct DOT #? It's entirely possible your master cylinder is bad but I would first double check that all your line fittings are tight and correctly threaded. Was a new banjo installed? If so , were new washers used and in the correct order? Heat related fade away is usually due to contaminated fluid or a bad master. Interesting scenario you have here considering you have done this proceedure before, presumably your master was fine before the new lines, and you have flushed enough fluid through to remove any contaminats
To be clear, they're not "fading"; i.e., braking effectiveness is not reduced, nor is the force required. There's also no gradual "creep" in lever travel when I clamp it, as I'd expect if the MC primary cup was bad or worn. It holds pressure just fine. There's just more total lever travel when warm.

It's all new fluid; definitely not contaminated or old. There are no leaks (which exonerates the washers, which are new). Master cylinder was fine before the new line was installed, and has been completely disassembled and cleaned.
 

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What happens when you pump brakes to bleed rather then use vacuum assistance is that the master cylinder piston is forced beyond its normal travel into where all the gunk accumulates at the end of the cylinder. The piston has either reversed a cup or been damaged by the gunk in the cylinder i'd say.
Steve
 

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Things I have found bleeding brakes.
Use new fluid that has sat on the bench for a day or two. If someone shook the fluid to mix it, dropped it or brought it home on their bike it will have air dissolved in it. Cannot bleed the system with aerated fluid. Push the pistons into the calipers. Tap the calipers with a screwdriver handle to dislodge air bubbles. Keep the front wheel straight ahead. When using a bleeder bottle and hose make sure the end of the hose is submerged in fluid. You may have to put some fluid in the bottle. If you tie down the brake lever over night any air in the system will dissolve in the fluid and form bubbles when the pressure is released causing a soft feeling lever. Work side to side. Try one side a bit then move to the other. If not going well have a beer and try again later. Be patient.:yesnod:
Good luck
Tom Hart
 

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I gave up and paid a shop $40 to do it their way. Now the front brakes are consistently mediocre -- i.e., normal. :beatnik:

Based on all the information I have available, they seem fine by this bike's standards. The brake feel is consistent with all the other complaints I've read about this bike. There is abundant stopping power, even though there's still a lot of lever travel.

I can't imagine anyone using anything other than position 1 on the lever cam, though. You certainly can't 2-finger at anything lower than that. At 5, it bangs against the handgrip very readily. :jawdrop:
 
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