I recently purchased a 2017 Zero FXS electric motorcycle, it's been a blast for commuting so far.
Riding it home though, I noticed the brakes were a little squishy and the fluid in the reservoir was dark, so one of the first things I did was flush and bleed the front and rear brakes. I definitely purged the air and the lever felt nice and firm after the flush. However, the next day, I went to ride it and it was squishy again. As I pulled the lever, I could see air bubbles coming out of the master cylinder into the reservoir. As I flicked the lever, more bubbles came out and the lever got firmer. Thinking I left a bleeder loose, I tightened the bleeders (at the caliper and MC) and tried checking the banjo bolts, which all seemed tight. Next day, same thing, squishy lever.
After some googling, I found the suggestion to use a bungee or zip tie to hold the lever down over night to let the air out. I did that and in the morning, the lever felt firm again. I've been doing that every night just to get by, but I swear, within my ~30-45 minute commute, I can feel the lever get squishier.
FWIW, the caliper and MC are J.Juan brand, and it does have a Bosch ABS system. I didn't check the banjo bolt connections to the ABS system yet as that goes into the chassis. Also, I haven't noticed the fluid level in the reservoir change in the past 2 weeks since I flushed it, so I don't *think* there's a leak.
Any suggestions on what to check next? Since holding the lever in seems to keep air out, I'm inclined to think it may just be the seals in the MC and I need to rebuild it.
Thanks for any input!
Riding it home though, I noticed the brakes were a little squishy and the fluid in the reservoir was dark, so one of the first things I did was flush and bleed the front and rear brakes. I definitely purged the air and the lever felt nice and firm after the flush. However, the next day, I went to ride it and it was squishy again. As I pulled the lever, I could see air bubbles coming out of the master cylinder into the reservoir. As I flicked the lever, more bubbles came out and the lever got firmer. Thinking I left a bleeder loose, I tightened the bleeders (at the caliper and MC) and tried checking the banjo bolts, which all seemed tight. Next day, same thing, squishy lever.
After some googling, I found the suggestion to use a bungee or zip tie to hold the lever down over night to let the air out. I did that and in the morning, the lever felt firm again. I've been doing that every night just to get by, but I swear, within my ~30-45 minute commute, I can feel the lever get squishier.
FWIW, the caliper and MC are J.Juan brand, and it does have a Bosch ABS system. I didn't check the banjo bolt connections to the ABS system yet as that goes into the chassis. Also, I haven't noticed the fluid level in the reservoir change in the past 2 weeks since I flushed it, so I don't *think* there's a leak.
Any suggestions on what to check next? Since holding the lever in seems to keep air out, I'm inclined to think it may just be the seals in the MC and I need to rebuild it.
Thanks for any input!