|Topic Review (Newest First)|
|02-08-2019 09:57 AM|
|nhsnowbird||My bike has ABS. I should have noted in my previous post that if you have ABS, you should find a safe place ( I use a nearby gravel parking lot) to CAREFULLY activate both your front and rear ABS a few times prior to bleeding. After bleeding it once, I again activate the ABS and bleed again. This is to ascertain that I have replaced as much of the brake fluid as I can. This method has worked very well for me and does not require a lot of time.|
|02-08-2019 09:43 AM|
|nhsnowbird||In lieu of speed bleeders, I have found that removing the bleeders (I use the rubber bleeder cap to plug the threaded hole temporarily) and wrapping the threads with Teflon tape and re-inserting makes the job much easier. Then use either a Miti-Vac or an assistant to make the job easier.|
|01-09-2019 12:47 AM|
In case it helps, I documented my experience with this problem:
TL;DR: this bike (which I'm still riding after 11 years and 60k miles) is wonderful, but its brakes are just crappy. I tried everything imaginable to fix the inconsistent lever travel, including a complete rebuild of everything except the caliper bodies. In the end, replacing the entire brake calipers was the only real fix. I have no freaking idea why.
I no longer waste my time refurbishing them; I flush them annually, and completely replace them every 4-5 years. This bike has been so reliable that it really isn't very expensive to do this when amortized over its life, especially if you're doing the work yourself. (Then again, understand that my last bike was a BMW K75 which I calculated cost me roughly $1 per mile to ride, so my frame of reference may be a little crooked ...)
YMMV. Good luck!
|01-07-2019 02:07 PM|
Originally Posted by Ratchet View Post
Yea bleed the brakes and check the pistons and stuff like everybody is saying.
Thing is though the 650 brakes aren't firm compared to a bike with really good brakes. I spent a few years on the 650 before going to a Gen 2 1000. Front brakes are night and day in regards to power and feel at the lever.
Some change out the 650's 2 pot calipers for 4 pots and switch out the master cylinder That would probably be the solution to get better brakes on the 650. Type of fluid, pads, lines, etc. aren't going to make much of an improvement, IMO.
|01-07-2019 11:23 AM|
Originally Posted by notacop View Post
|01-07-2019 11:17 AM|
If you're going to bleed the brakes, this makes it easy, one person job.
|01-07-2019 09:07 AM|
When you change the fluid I have gone to either Super DOT 4, or DOT 5.1. Both have a higher boiling point that DOT 3, so better performance when really hot or overheated.
I recently had a spongy front also, replaced all fluid with Super DOT 4 and changed the HH pads out to Ferodo:
I reverse bleed the system and make sure you get all the DOT 3 fluid out since combining/mixing DOT 3, 4 or 5.1 can possibly cause master or caliper failure. The front brake lever is now firm like it is supposed to be and I like the Ferodo's over the EBC HH's.
|01-07-2019 03:56 AM|
Originally Posted by Hatchi View Post
I had a Harley V-rod come to me with such a soft spongy lever it was dangerous to ride. The issue was.. caliper piston seals sticking to the pistons and retracting them into the caliper bores when the lever was released. Found by being able to insert a .025" feeler gauge between the brake pads and the rotor 5 seconds after brake application sitting in my garage. The pistons themselves were free, but the seals kept pulling them back into the bore. Talking with the local H-D dealer's parts guy, he told me this was a very common situation, caused by brake dust on the outer seals.
The repair was to replace the the piston seals. I have had pistons stuck in the caliper bores from old fluid and rust, but the symptom was dragging brakes pads and overheated rotors not a spongy lever. This H-D used silicone fluid(H-D recommended), and the spongy lever wasnt from boiling fluid from overworked brakes when hot.
|01-07-2019 02:49 AM|
Cleaning the caliper and pistons is worth doing, for some reason the 650 pistons are crap magnets, particularly for small pieces of tar coated gravel from new seal.
eBay rotors are relatively inexpensive if it's a warped rotor.
Wheel bearings are also a possibility.
Another possibility - aka the nightmare scenario. Crap in the ABS valve. Symptoms there are if you get the brakes firm and hold them the lever slowly heads for the bars. That's sometimes fixable.
|01-07-2019 02:40 AM|
Originally Posted by Hogges View Post
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