Air Shocks

[rewindgy]

So I had a Dealer replace the defective Right side shock and was running the shocks with out the Progressive cross over kit. Since I pull the trailer frequently I decided to put the cross over kit back on and noticed something odd? Lifted bike so rear wheel off ground and filled to 35 psi - put bike back on ground psi pops up to 45 psi. Hmm!!! I had left the pump on so to see if any fitting leaked down. So, I bounce bike up and down and guage goes from 25 - 75 psi. So, this may be normal but????
What I need someone with the stock single shock fill set up - hook their progressive pump up and read the pressure with bike on side stand - then take off side stand and let bike sit - then bounce it up and down. I need to know if the guage tracks the same as mine? Since I put Liquid teflon on the fittings I really don't want to take them apart unless I really have too!!

Thanks in advance.

[Yellow Jacket]

As the shocks get compressed the air pressure will rise. Haven't ever tried it with a guage attached but it has to do this. As the volume is decreased under compression the pressure can do nothing else but go up.

[cactusjack]

Doesn't the owner's manual say to fill/adjust the shocks with the rear wheel off the ground? Maybe this is why - so you get a consistent unloaded measurement.

[ringadingh]

I always check my shocks with the bike on the ground, I cant see jacking it to do this all the time.

[rewindgy]

I know every other bike I've had with Air shocks you had to fill with wheel off ground - but I never left a guage on them to see what happened! Ima guessing this is normal but since having one shock go south I really don't want to lose another - not a $550 a pop!!

[cnc]

Originally Posted by Yellow Jacket

As the shocks get compressed the air pressure will rise. Haven't ever tried it with a Gage attached but it has to do this. As the volume is decreased under compression the pressure can do nothing else but go up.

This is true.
The default setting from the factory is 0 psi with the weight of the bike off the back wheel. When I first put a gage on my shocks this translated to about 18 psi sitting on the ground. I believe there is something about this in the owners manual.

[dogdoc]

I've always filled mine on the ground like Ring. This might be wrong but thats how I do it and it works for me.

[watchman]

The owner's manual, page 136, does state," Raise the rear wheel off of the ground by using a suitable jack". The air pressure adjustment table in the manual states from Atmostpheric pressure to 300kPa ( 3.0 kg/cm2, 43 psi) depending on the ride your want. But then on the next page in the Caution Box is states, "Air pressure exceeding 500 kPa (5.0 kg/cm2, 71 psi) may damage the oil seal". So with 35 psi of air in the shocks and when bouncing the bike you are hitting 75 psi I would conclude that you should lower the air pressure until you do not exceed the maxium 71psi. This is just my reasoning and others may disagree.

[waterman]

Originally Posted by watchman

The owner's manual, page 136, does state," Raise the rear wheel off of the ground by using a suitable jack". The air pressure adjustment table in the manual states from Atmostpheric pressure to 300kPa ( 3.0 kg/cm2, 43 psi) depending on the ride your want. But then on the next page in the Caution Box is states, "Air pressure exceeding 500 kPa (5.0 kg/cm2, 71 psi) may damage the oil seal". So with 35 psi of air in the shocks and when bouncing the bike you are hitting 75 psi I would conclude that you should lower the air pressure until you do not exceed the maxium 71psi. This is just my reasoning and others may disagree.

Watchman,

I think that they take into account the bouncing and flucuation of air pressure. If you were to fill it up to 71 and then bounce it would blow the seals. However, who would want that stiff of a ride.

[samkjr]

I just had an AH HA moment here then. When my wife and I ride together we bottom out on bad dips and some road bumps. I have always filled from the side stand, and keep it at 38.

Are we saying I should jack it up and then put it to 38? That would be a much beeter stiffer ride when two up.

[cnc]

samkjr, Yes. If you consider what I experienced in my post you may only have about 20psi when the rear of the bike is off the ground.
It might be interesting to check your psi before jacking your bike and again after the back tire is in the air to compare.

CNC

[danleb75]

Originally Posted by samkjr

I just had an AH HA moment here then. When my wife and I ride together we bottom out on bad dips and some road bumps. I have always filled from the side stand, and keep it at 38.

Are we saying I should jack it up and then put it to 38? That would be a much beeter stiffer ride when two up.

Can you let us know what the 38 psi setting with the rear wheel in the air gives you when you set it back down?

Thanks.

[dogdoc]

I know what the manual states but I really can't see jacking the bike up EVERYTIME you need to make an air adjustment. I feel if you put 10-20 psi which is all I do, then your not ever going to hit 71 psi and blow the seals. Who really knows what one psi is jacked up vs same psi down on the ground. they would give a table i would think if it was all that important. IMO!

[danleb75]

Originally Posted by Doc (Lonewolf)

I know what the manual states but I really can't see jacking the bike up EVERYTIME you need to make an air adjustment. I feel if you put 10-20 psi which is all I do, then your not ever going to hit 71 psi and blow the seals. Who really knows what one psi is jacked up vs same psi down on the ground. they would give a table i would think if it was all that important. IMO!

True, at 10-20psi youèll never reach 71psi. However, at 10-20psi with a passenger and both bags full, the bike will bottom out. I'd like to find a psi that I can stick with, and just adjust the dampening I,II,III,IV depending on how the bike is loaded.

By myself, I'm 280lbs. Loaded with gear and wife, we're 440lbs.

[rewindgy]

Okay, so far on mine ( not sure about anybody elses) the difference from wheel on ground to wheel off ground is about 7 Pounds. Note: I have both shocks to a single inlet. ( I also checked this with seach shock individual!) So, with bike on ground with minimal junk in bags & trunk if I put 27 PSI in shock I actually have 20 PSI as per Mother Kaw wheel off request. I find that 35 PSI reading on ground is very good with 2 up and trailer. 25 PSI on ground is plush ( rebound @ 2) for 1 up not loaded to the nuts. Just an FYI.