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Makes And Models => Zero Motorcycles Forum | 2013+ => Topic started by: WDavis4692 on February 07, 2017, 02:00:55 AM

Title: [2016 FXS] Rear brake light comes on way too late
Post by: WDavis4692 on February 07, 2017, 02:00:55 AM
The bike is new.  The first thing I did was lower the height of the brake pedal to suit my comfort.  Unfortunately, the point by which regen and brake light actuates is too late.  It's beyond the biting point of the pedal for sure.  The brake light comes on when the pedal is depressed around 40-50% of its full travel; so basically it's possible to brake in a gentle-moderate fashion without the light coming on.

The unofficial Zero manual online said something about adjusting a set screw in the lever somewhere that allows you to fine-tune the amount of brake pressure/lever travel required before the light (and regen) become active, but I can't for the life of me figure out where I'm supposed to be looking.

Is anyone here able to help, please?
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: 2ballde on February 07, 2017, 05:48:48 AM
The rear brake switch is activated hydraulically by pressure in the rear brake system. It could be you have some air in the rear system and needs extra lever pressure to close the switch. The threaded rod from the brake lever to the master cylinder adjusts lever height. This a SR rear mc no adjustments except for lever height. Switch is built into top banjo bolt.
 
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: domingo3 on February 07, 2017, 08:18:27 AM
The unofficial Zero manual online said something about adjusting a set screw in the lever somewhere that allows you to fine-tune the amount of brake pressure/lever travel required before the light (and regen) become active, but I can't for the life of me figure out where I'm supposed to be looking.

This is referring to the front brake (hand lever), which explains why you were frustrated looking for it on the rear.   :)
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: BrianTRice@gmail.com on February 08, 2017, 09:37:56 AM
Well, this is one way to fix the wiki manual!

I've added and referenced 2ballde's notes here at http://zeromanual.com/index.php/Unofficial_Service_Manual#Rear_Brake_Actuator (http://zeromanual.com/index.php/Unofficial_Service_Manual#Rear_Brake_Actuator)
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: WDavis4692 on February 08, 2017, 07:06:51 PM
Ah ok thanks so you can just unwind the banjo bolt slightly or something?  I'm not convinced the brakes need a bleed.  The bike is practically new out of the factory and I've rode it a few times, brakes feel responsive and fine.  I took the metal plate that guards the master cylinder off the bike to get to the cylinder so I can see the banjo bolt you refer to.  I'll dig around and see if I can also find some J-Juan nomenclature before I go fiddling with anything.
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: Fred on February 08, 2017, 07:35:07 PM
Don't "unwind the banjo bolt"! That will cause a leak and your rear brake to fail.

Bleed the brakes in the normal way if you think there might be air in there. (I'm sure a quick search will show up lots of videos showing how.)
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: WDavis4692 on February 08, 2017, 08:55:56 PM
Oh, no, I'm not convinced there's air in the brakes like I said :)  I just want to find out what element to adjust to make the light come on sooner.  Or were you trying to say this element cannot be adjusted at all?

Thanks for helping so far.
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: Richard230 on February 08, 2017, 09:22:15 PM
Oh, no, I'm not convinced there's air in the brakes like I said :)  I just want to find out what element to adjust to make the light come on sooner.  Or were you trying to say this element cannot be adjusted at all?

Thanks for helping so far.

I am pretty sure that a brake fluid pressure switch can not be adjusted.  If it is not working properly (after a good brake bleed) then it likely needs to be replaced.  My recollection is that Zero had a formal recall a couple of years ago for a similar problem.
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: Lenny on February 09, 2017, 12:28:50 AM
Just checked this issue on my FXS today, comes way to late as well. I'll do some further investigation as soon as I have enough time.
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: rayivers on February 09, 2017, 12:57:17 AM
To the OP - unless you can find an adjustable hydraulic-type switch to replace the Zero unit (I couldn't), I think you're out of luck with the OEM setup.  I understand why Zero went this route - it's cheap, easy to install, requires no setup, etc. - but IMO a separate adjustable switch (like the vast majority of performance-oriented street bikes use for their brake lights) is clearly the way to go if you're serious about getting regen-braking activation exactly right for your riding style & brake-pedal positions, & independent of anything else.

This switch (http://www.ebay.com/itm/Universal-Motorcycle-Rear-Brake-Light-Switch-Spring-For-Honda-Kawasaki-Suzuki-/322171215841?hash=item4b02e69fe1:g:jH4AAOSwukdXcPJp&vxp=mtr) is inexpensive and has an extra-long spring to reach the brake pedal, but otherwise I have no idea how good (or bad) it is.  To make it or something similar work, you'd need a frame bracket in the right spot with enough clearance to reach the brake pedal with the spring.  If it were me I'd also install a mating connector on this switch to connect it to the OEM brake-switch connector for regen triggering, then rewire the OEM hydraulic switch to activate only the brake light (independent of the harness connection). Yeah, it's a significant amount of work - if I had a one-tool, 5-minute fix I'd share it, believe me. :)

Ray

(http://i.ebayimg.com/images/g/jH4AAOSwukdXcPJp/s-l1600.jpg)
Title: Re: [2016 FXS] Rear brake light comes on way too late
Post by: 2ballde on February 09, 2017, 04:11:15 AM
rayivers is on to something as maybe this is a common FX problem. If the rear brake system is properly bled. You could mount the separate switch where it is most practical, cut the extra long spring to the length you need for proper actuation. The stock sw. wires go to a connector on top of the motor( on an SR). Cut the wires, connect up to the wires on the new mechanical sw. and you have an adjustable sw. you can have activate where you want it to for the brake light and the ABS just like the hydraulic sw,. Just leave the hydraulic mc,/sw. as is to avoid re-bleeding. Over the years I've re-purposed various simpson metal brackets( found at most hardware stores) for mounting stuff to motorcycles. A little paint and they look fine.