Alright brake guru's, let me know what your thoughts are on my issue.
Yesterday was the first commute to work on the scoot. It's about a 30 mile ride in to work. Leaving work all is fine until I get less than a mile down the road from leaving the parking lot and the front brake locked up while going down the road at 60 mph. Yes, as I'm going down the road and I begin to feel the bike bogging down while I'm giving it gas but it's continuing to slow down. I look down to the front wheel and see smoke starting to come from the front brake/rotor. I get pulled over to the side of the road, and I have to use both hands in order to pull the brake lever in. It would not free up. So out comes the multi tool and I do a quick bleed of the front caliper. That free'd it up, and I was back on the road but with a mushy brake lever. By the time I pull up at my house, (30 miles back home), the brake lever was back up to pressure and functioning as it always has. I completely flushed & replaced the brake fluid, removing the original brake fluid from when I got it new in 2000, at the beginning of last year with no issues last year. Is it time to rebuild the caliper(s), or should I just do another brake fluid flush/bleed job?

 

I had this happen on my last bike and found that the plunger at the master cylinder was being slightly pushed on by a new set of levers...the adjustment screw that is. check the clearence between the brake lever and the plunger...I cant visualize it as I am at work.

 

yes...to the first one

 

Do your laundry yet?
For something that serious id probably either go to the dealer or replace every thing from the pads to the lines.
Probably water in the system, but how did it get there? When was your last fluid flush?

 

Have you installed new lever recently? That can cause your brakes to lock up, had it happen on a CBR. Also, the pistions in the caliper my be dirty, causing them to stick. I would check my levers, and take the calipers off the bike clean the pistons with a q-tip and cleaner. Then bolt it back together and rebleed the system. Make sure to use the correct brake fluid. My 00' calls for dot 5.....check what yours is.

 

No need to launder the shorts. I don't have the dealer service my scoot. I do the services. Last fluid flush was spring time last year. Replace all of the fluid in the both the front and rear.

 

To Aaron and Emperor, no new levers. Still using the oem/stock levers. Brake acted fine once I did one bleed cycle on the side of the road. It's been fine all night while running from daughter's basketball game then to her softball practice, and then back home again, and it has acted normal on the commute in to work today.

 

You may have had a piece of debris in the plunger that bled out and was maitaining pressure.

 

OK, Update!!! Front brake did not lock up this morning on the 30 mile commute into work at ~60 degrees. The bike sat in the parking lot in the sun all day long while the temp heated up to about 80 degrees. The daily temp change was about the same both days. This time I make it less than two miles up the road before the front brake locks up with me only being able to make it about one foot off the road with tractor trailer/cars flying by. I do not remember, either day, if I grabbed the front brake lever to slow down due to traffic ahead. I had to do another one bleed cycle of the brake on the side of the road to free it up. This time the mushyness did not go away after about a 50 mile trip back home & running to a couple other needed spots. I had to use the rear brake solely. I'm running out right now to do an actual brake bleed to see if I can get it to clean out better. I'm thinking I might need to just do the front caliper rebuild because I've always mainly used the front brake during slowing/stopping with only some use of the rear. However, I'm wondering if there might be an air bubble heating up during the day locking the brake up shortly after I begin rolling after work.

 

Also, NO, I can't take my truck to work until I do the caliper/master cylinder rebuild on the bike because my truck has been in the shop since Monday getting a new parking brake assembly/axle gaskets redone because the parking brake assembly decided to break apart destroying the entire driver side rear brake assembly, which I do/did not have time to fix myself due to a variety of issues.