Air pressure in rear shock .....

[bmwlarry]

I have a 2015 RT Limited with the automatic air level adjustment. My 2015 has always rode a lot harder and bumpier than my 2011 Limited. Dealer checked it over and said all was normal. I checked the air pressure on the rear shrader valve under the seat and it was 12 lbs. We added air up to about 40 lbs. I called the tech and he informed me it does not matter what you manually add, when the bike is started, in gear - the auto system will correct it to where it should be. Last week while on a ride with a friend, also with a limited, we noticed that while the bikes were parked and unloaded, mine was about 3 inches lower that his at the lowest part on the rear fender (I checked the air pressure when I got home and it was sitting in garage - 31 lbs) . I never seem to hear anything when we get on and start it but his makes a noise. I am hard of hearing and it may just be me. Do I have a bad air pump or bag??

 

[Devious56]

I too have a 2015 RT Limited, and unfortunately I can not tell you what your rear air suspension system is doing. I have never heard my air pump run, and to be on the safe side, I have gotten in the habit of checking the pressure in my bladder before every ride, just like I do the pressure in my tires. I try to keep 60 pounds in it as I usually ride two up. If I lower or increase the setting with the switch, it seems there is a difference in the ride (softer or firmer). but I don't want to be caught in a situation where I don't have enough air in the bladder. Good luck with you situation, and if I come up with a way to tell for sure (yes, I have followed the instructions in the shop and owners manual) I'll post something back here.

David

 

[Highwayman2013]

I have a 2015 RT Limited with the automatic air level adjustment. My 2015 has always rode a lot harder and bumpier than my 2011 Limited. Dealer checked it over and said all was normal. I checked the air pressure on the rear shrader valve under the seat and it was 12 lbs. We added air up to about 40 lbs. I called the tech and he informed me it does not matter what you manually add, when the bike is started, in gear - the auto system will correct it to where it should be. Last week while on a ride with a friend, also with a limited, we noticed that while the bikes were parked and unloaded, mine was about 3 inches lower that his at the lowest part on the rear fender (I checked the air pressure when I got home and it was sitting in garage - 31 lbs) . I never seem to hear anything when we get on and start it but his makes a noise. I am hard of hearing and it may just be me. Do I have a bad air pump or bag??

Have you adjusted the air ride on the dash? If you set it harder it will maintain more air pressure. It has a leveling system so if set lower it will leave air out. The compressor is fairly quiet so you may not hear it. To test it you could let air out of the shader valve and then start the bike, put in gear, and release the brake and see if the rear of the bike rises.

 

[Frank G]

If you want to see your air suspension work, do this. On a level surface, at night or low light, lights on low beam pull up to any wall or garage door about 20 to 30 ft away. With the engine running, in gear, parking break off, foot on brake. move the suspension switch up or down and watch your headlights move up or down the wall. If nothing moves something is wrong. It's as easy as that. Have the wife get on the back and watch the bike adjust to the proper alignment. :cheers:

The system will normally over correct with pressure then release some air.

Some air pumps are very quiet and others can be herd at speed.

 

[bmwlarry]

Soooo .... I put started my bike, put in gear chucked the front wheels and released the brake & attached an air-pressure gauge to the valve.

With no body on the bike:
shock setting - air pressure read - rear lower fender height
softest - 0 - 14 in.
+1 - 0 - 14 in.
+2 - 8 - 14.5 in.
+3 - 18 - 14.75 in.
hardest - 19 - 15. in.

with me (150 lb) on bike - didnt have anyone to check height
shock setting - air pressure read - rear lower fender height
softest - 8 - 14 in.
+1 - 20 -
+2 - 30 -
+3 - 35 -
hardest - 40 -

Soooo the pump is working.
I checked the air pressure over the next three hours and it held for the first 2 hours and then went to 0. airbag leak??

 

[finless]

Yep... it's leaking... It should not go down on it's own that fast.

Could be the bag, valve, or something at the pump.

Bob

 

[bmwlarry]

Soooo .... I rode it to the shop yesterday and mad an apt to have the belt replaced. On the ride home I set the shock to the hardest setting. When I shut it of at home around noon, the shock was at 44 lbs and fender height at 16 in.

This morning it is still at 40 lbs and fender height is 15.75.

Go figure!

 

[Frank G]

Soooo .... I rode it to the shop yesterday and mad an apt to have the belt replaced. On the ride home I set the shock to the hardest setting. When I shut it of at home around noon, the shock was at 44 lbs and fender height at 16 in.

This morning it is still at 40 lbs and fender height is 15.75.

Go figure!

Depending on how you are checking the pressure you may loose 4 PSI Just checking it. There is not a lot of air volume in the system. As for the height difference :dontknow: