adding air to shocks

I just received my repair manual in the mail today, it says I should put my bike up on the center stand before adding air to shocks. The center stand is not on it, and when I attempted to put it on it looked like the exhaust would have to be removed first. The guy I bought this bike from had it removed because the spring was weak. There is no mention in this repair manual about the center or side stand, I'm wondering just how good this manual is. Does it make much difference to have it on the center stand before adding air?

Yes, it will make a difference. You need to find a way to raise the rear wheel off the ground, like those stands the racers use that raise the rear at the axle.

I asked a mechanic at a local Harley dealership after I posted and he said it shouldn't make any difference. I'd like to have the center stand back on just because it's supposed to be on there. I don't want to do it yet because I don't have exhaust gaskets in case I need them.

chiaronate wrote: I asked a mechanic at a local Harley dealership after I posted and he said it shouldn't make any difference. I'd like to have the center stand back on just because it's supposed to be on there. I don't want to do it yet because I don't have exhaust gaskets in case I need them.

:laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh:

You're kidding right? A Harley mechanic knows more about Kawasaki suspensions then the guys who wrote the Kawasaki service manual? No offense intended, but it sure sounds like you are simply believing what you want to hear. Ed

Perhaps you can tell me the difference between the Harley and Kawasaki shock absorber technology that makes putting the Kawasaki up on the center stand necessary? Do you take your car tires off before putting air in them?

650ed wrote:

chiaronate wrote: I asked a mechanic at a local Harley dealership after I posted and he said it shouldn't make any difference. I'd like to have the center stand back on just because it's supposed to be on there. I don't want to do it yet because I don't have exhaust gaskets in case I need them.

:laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh: :laugh:

You're kidding right? A Harley mechanic knows more about Kawasaki suspensions then the guys who wrote the Kawasaki service manual? No offense intended, but it sure sounds like you are simply believing what you want to hear. Ed

I figure the only reason it says to use the center stand is so the added air pressure doesn't make it fall over. It is a Japanese motorcycle, maybe it just didn't translate right into English.

Putting the bike on the centerstand takes the pressure off the shocks and gives you a realistic reading. If you have weight on it you increase the indicated pressure, but it is not the true pressure.
And just because he works on motorcycles does not mean he is all-knowing. Just my two cents worth.
As I always say, its your bike, do as you wish. Me, I follow the book, but that's just me.

I can't follow the book because the center stand isn't on it. On the plus side, if I just take the mufflers off I can bolt on the center stand. I was looking at them and saw that removing the mufflers is all I'll need to do. Should they come off fairly easily, or should I not bother to try because they're probably welded from rust and heat?

koolaid_kid wrote: Putting the bike on the center stand takes the pressure off the shocks and gives you a realistic reading. If you have weight on it you increase the indicated pressure, but it is not the true pressure.
And just because he works on motorcycles does not mean he is all-knowing. Just my two cents worth.
As I always say, its your bike, do as you wish. Me, I follow the book, but that's just me.

chiaronate wrote: I figure the only reason it says to use the center stand is so the added air pressure doesn't make it fall over. It is a Japanese motorcycle, maybe it just didn't translate right into English.

That simply is not the case. It's your bike, so do what you want with it, but for anyone else who might read this thread and who might have other wise believe your Harley guy I offer the following thoughts...

FORKS ELEVATED:
The bike in this case is sitting on the center stand and we use a bottle jack under the front of the engine to lift the front of the bike (forks, wheel, and all) off the ground. The forks are now fully extended. The top fork bolts are out of the forks, so there is zero air pressure inside the forks at this point. Now we install the top fork bolts. We now have a column of air trapped inside each fork tube, but there is still no air pressure inside the forks. Now we add 7 psi of air. The air pressure is now 7 psi inside the forks. If we now lower the bike off the jack and off the center stand we have approximately half the weight of the bike (let’s say 200 pounds after accounting for unsprung weight) applying downward force on the forks which already had 7 psi of air inside. This downward force on the fork tubes will further compress the air trapped inside and cause the air pressure inside the forks to rise above 7 psi.

FORKS NOT ELEVATED
The front of the bike is not elevated; the bike is sitting upright on both tires. Approximately half the weight of the bike (let’s say 200 pounds after accounting for unsprung weight) is applying downward force on the forks. We open the Schrader valve and adjust the air pressure to a total of 7 psi. We’re finished, and the air pressure inside the forks will be 7 psi.

It should be clear that under the first scenario the resulting air pressure inside the forks when finished will be greater than that of the second scenario. It may not be a huge difference, so again, do what you like.

A bigger question is when was the last time you changed your fork oil, and how will you do that if you can't lift the front of the bike off the ground? Of course, you may chose to try to do that with the forks on the ground, but I wouldn't recommend it even if the Harley guy thinks it's a good idea. Ed

chiaronate wrote: ....Do you take your car tires off before putting air in them? ...

No; is that what your Harley guy recommends? My goodness, he does offer some unusual advice. Maybe that advice came from a Harley Service Manual. Ed

The point is if a tire that goes onto a multi-ton automobile can be inflated to the right pressure and not have to be adjusted after it has the vehicle's weight on it, a few hundred pounds of motorcycle shouldn't make any worthwhile difference. I also see a lot about not using an air compressor to add the air because it will blow out seals. I used gas station compressors to inflate the shocks on my 1982 Nighthawk without issues. I do like the accuracy that the Harley shock pump is supposed to provide, I'm eagerly waiting for it to be delivered.chiaronate" post=602533]I figure the only reason it says to use the center stand is so the added air pressure doesn't make it fall over. It is a Japanese motorcycle, maybe it just didn't translate right into English.[/quote]

That simply is not the case. It's your bike, so do what you want with it, but for anyone else who might read this thread and who might have other wise believe your Harley guy I offer the following thoughts...

FORKS ELEVATED:
The bike in this case is sitting on the center stand and we use a bottle jack under the front of the engine to lift the front of the bike (forks, wheel, and all) off the ground. The forks are now fully extended. The top fork bolts are out of the forks, so there is zero air pressure inside the forks at this point. Now we install the top fork bolts. We now have a column of air trapped inside each fork tube, but there is still no air pressure inside the forks. Now we add 7 psi of air. The air pressure is now 7 psi inside the forks. If we now lower the bike off the jack and off the center stand we have approximately half the weight of the bike (let’s say 200 pounds after accounting for unsprung weight) applying downward force on the forks which already had 7 psi of air inside. This downward force on the fork tubes will further compress the air trapped inside and cause the air pressure inside the forks to rise above 7 psi.

FORKS NOT ELEVATED
The front of the bike is not elevated; the bike is sitting upright on both tires. Approximately half the weight of the bike (let’s say 200 pounds after accounting for unsprung weight) is applying downward force on the forks. We open the Schrader valve and adjust the air pressure to a total of 7 psi. We’re finished, and the air pressure inside the forks will be 7 psi.

It should be clear that under the first scenario the resulting air pressure inside the forks when finished will be greater than that of the second scenario. It may not be a huge difference, so again, do what you like.

A bigger question is when was the last time you changed your fork oil, and how will you do that if you can't lift the front of the bike off the ground? Of course, you may chose to try to do that with the forks on the ground, but I wouldn't recommend it even if the Harley guy thinks it's a good idea. Ed[/quote]

Also, why let out air after taking it off the stand? The manual doesn't mention that.