My 2003 ST1300 (non ABS) has 102,000 miles on it now and I recently found a very hot rear disk while I was on a weekend ride. I couldn't feel any difference in the usual operation of the brakes but thought I noticed a drop in gas mileage. So I checked the rear disk and found it very hot to the touch. After I got the bike home I started to research the problem through the forum here and decided to call Larry (Igofar) and see if he would help me find out what (if anything) was wrong with my brakes. I can't say enough about Larrys' help and know many of you relied on his expertise also. I have bled (flushed) my brakes and changed pads but that was the extent of my maintenance experience. After talking to Larry I began to work through his trouble shooting procedures and the disk is running cooler now and I feel much better about the health of the braking system.
Before I discovered the hot rear disk I had flushed the system and I'm not certain I got a good bleed. It is possible that I did not get a proper bleed. The first suspect was the SMC. I took it apart and found no corrosion under the boot and the piston moved freely in the bore. Since the bike is over 100,000 miles I followed Larrys recommendation and replaced the SMC. I checked the pivot needle bearings on the left caliper assembly, it all looked good. I added fresh silicon grease to the bearing and checked the top mounting bolt and washers. I bleed the system again, only i pumped the lever and pedal to bleed versus the Mity Vac vacuum method. I then pulled the rear caliper, cleaned and greased the sliding dowels and replaced the pads with new OEM Honda pads. I also ordered new OEM pads for the fronts and changed those, cleaned the pistons and lubed the sliding dowels.
I'm not able to say which if any single thing that was changed solved this hot rear disk issue. I did a lot of test rides and started using an infrared temperature gun to see if the disk temperature decreased and it did. Is it normal now? I can't say what that normal temperature is if you just jump off the seat after a ride and check it?
My disk temperature went from 71F (cold) to 88F after a 10 mile ride (no hard braking). The maximum temperature I read was 117F before most of the maintenance was done. It was just a crude method of trying to get some relative meaurements to verify improvement. I'm sorry to be long winded here but I mostly wanted to share my observations and thank Larry for all his knowledge and help. He really hung in there with me by phone, text and PM during a pretty lengthy process.
I know it's not easy guiding an Olegeezer with limited skills through a braking system this complicated.
Safe riding and efficient braking to yuns.
Before I discovered the hot rear disk I had flushed the system and I'm not certain I got a good bleed. It is possible that I did not get a proper bleed. The first suspect was the SMC. I took it apart and found no corrosion under the boot and the piston moved freely in the bore. Since the bike is over 100,000 miles I followed Larrys recommendation and replaced the SMC. I checked the pivot needle bearings on the left caliper assembly, it all looked good. I added fresh silicon grease to the bearing and checked the top mounting bolt and washers. I bleed the system again, only i pumped the lever and pedal to bleed versus the Mity Vac vacuum method. I then pulled the rear caliper, cleaned and greased the sliding dowels and replaced the pads with new OEM Honda pads. I also ordered new OEM pads for the fronts and changed those, cleaned the pistons and lubed the sliding dowels.
I'm not able to say which if any single thing that was changed solved this hot rear disk issue. I did a lot of test rides and started using an infrared temperature gun to see if the disk temperature decreased and it did. Is it normal now? I can't say what that normal temperature is if you just jump off the seat after a ride and check it?
My disk temperature went from 71F (cold) to 88F after a 10 mile ride (no hard braking). The maximum temperature I read was 117F before most of the maintenance was done. It was just a crude method of trying to get some relative meaurements to verify improvement. I'm sorry to be long winded here but I mostly wanted to share my observations and thank Larry for all his knowledge and help. He really hung in there with me by phone, text and PM during a pretty lengthy process.
I know it's not easy guiding an Olegeezer with limited skills through a braking system this complicated.
Safe riding and efficient braking to yuns.