Honda XRV Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 · (Edited)
This is odd. I have a new/used 2008 Varadero with ABS. It runs great on the highway. However, twice now the same issue has cropped up.

Yesterday, riding home from the mall, it happened at a stop light. I stopped for the light, but when the light changed and I started to go, the brake would not completely release. It was not on full, but definitely on. The front hand leaver had zero slack and felt as if it was it was being applied. I managed to make it the short distance home without issue though the brakes were still pulling. ABS light was not on.

I scanned the forums and found that if there was a tire pressure differencial between front and back. ABS could be affected. I checked my tire pressure and it turns out the front was quite low. Thinking this could be the source I topped it up. Things seemed to be ok after.

On my ride this moring everything was good. I was about 15km into the trip and got stuck waiting to get on the highway at a metered on ramp. It was quite a long line to get on. The bike had been idling for about 5- 10 minutes when the cooling fan came on. Immediately, after the brake started to act up up again. It was grabbing on the front again. This is on the ramp, just as I was about to merge with the stop and go traffic highway traffic.

I pulled over, restarted the bike. But no change. I carried on to get to the next ramp to get off and find some service. By the time I got to the next ramp, all was good again.

This makes me wonder, what is the potential impact of the fan on the electrical system? Is the additional power drain going to have an impact on the ABS performance. Things seem to right themselves once I got moving and the air started flowing over the bike.

Some of the forum posts in my queries link battery and braking.

I have not tested the battery, but it seems to start the bike ok.


In the past week since I have had the bike I've put close to 500KM on it and this only seems to be an issue at stops when travelling at low or no speed.

Any insights are appreciated.



TC
 

·
Premium Member
Joined
·
6,168 Posts
Next time it does it try disabling the ABS by removing the two 30A fuses (in the separate fusebox) under the seat and see if that causes the brakes to release.

In saying that my money is on something sticking and non ABS related.
 
  • Like
Reactions: toc2

·
Registered
Joined
·
7,741 Posts
I'd second what Gordon say's, the ABS is a passive system - any malfunction & the brakes will operate as they would on a non ABS bike. Remove the fuses or unplug one of the sensors to disable the system.

I'd check the front lever & rear pedal pivots are free other than that, I dunno a problem/dirt in one of the master cylinders?

Phil
 

·
Registered
Joined
·
4,811 Posts
My guess is that it's unrelated to the ABS. (The ABS releases the brakes, it doesn't apply them!)

The first thing to check is whether the calipers are seizing. That happen if there's a build-up of dirt or corrosion inside the brake caliper cylinders. You'll need to remove the front wheel. Using a clean lever between the pad and the piston (not between the two pads) push each piston back. They may be a little firm, but the pistons should slide back smoothly.

You mentioned that the lever had no slack. This makes me think there's a problem with the master cylinder.

I've never had brake fluid boil, but apparently it can if there's dampness in the brake fluid. Does anyone know if this would cause the same symptoms?
 
  • Like
Reactions: toc2

·
Registered
Joined
·
1,007 Posts
I've never had brake fluid boil, but apparently it can if there's dampness in the brake fluid. Does anyone know if this would cause the same symptoms?
If there's water in the fluid, it boils well before the brake fluid ( 100+degC vs 500+degC) and turns to steam. Depending on whether fluid can escape back to the master cylinder, the brakes either go spongy, very spongy indeed, in fact, so spongy that you can cr*p yourself, or the brakes are forced on even harder. This, too, can result in soiling. It's unlikely to be the cause in this case, as it happened after a long standstill, and the water needs heat going into the brakes to boil. It could conceivably be heat soak, but you'd need the lever to be squeezed to stop fluid release, to cause locking.

I reckon you were right first time: master cylinder or caliper problem.

By the way, does the ABS on bikes have a pressure reserve and pump, like cars? I've never had a bike with ABS, so I don't know whether it just periodically releases the brake, or whether it then uses the reserve to re-apply them.
 

·
Registered
Joined
·
348 Posts
Check around the left front caliper there is a pivot bolt that operates the rear caliper via a slave cylinder under braking attached to the fork leg, I have seen these sieze and give similar problems, in the worst case the fork leg pivot can break.
 
  • Like
Reactions: toc2

·
Registered
Joined
·
367 Posts
hi, i dont know if this would apply to your bike. this happened to my dominator (non-abs obviously). it turned out to be the slider pins on the caliper sticking due to dirt, etc. the calipers wouldnt release all the way so it was always on and building up heat until eventually it would seize the pins solid hence the brakes. it would work again after it had time to cool down. after a good clean and grease, it has worked faultlessly. this was two years ago. while the calipers are out might be worth cleaning the pistons and lube them with brake piston grease. hoope this helps. regards. mark
 

·
My Blue Beast
Joined
·
756 Posts
i agree with Mark.......especially as you mention alls fine in between ramps:confused: ....as the bike gets a certain amount of cooling travelling along. look at the simple stuff before ripping sh&t out of the bike ( abs systems etc ) and maybe enter a whole world of hurt. good luck !
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #10 ·
Thanks.

My first plan of attack will be to clean and review the brake assembly. I picked it up in torrential downpour and had to ride two hours in the rain. Who knows what kind of grit found it's way in. I don't know the maintenance history, so this could be a worthwhile place to start.

Thanks
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #11 ·
As a first attempt at a fix I blasted the front calipers with brake cleaner. Rode in today without issue. Will need to see if this is the ticket.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #12 ·
Sometimes the simple stuff gets overlooked amongst the complexities. Barkbusters were binding on the brake lever. Adjusted and now all is good.
 
1 - 12 of 12 Posts
Top