View Full Version : Rear Shock Pressure
I am hoping the vast knowledge here will help me skip a little of the trial and error method on getting to the correct air pressure in the rear shocks.
I have ridden for a year with NO pressure in them and on occasion, though rare, will bottom out when riding two up or even scrap the V&H baggers (the nut/screw on the bottom) when pulling out of a parking lot too fast.
I am no light weight 270ish http://s2.images.proboards.com/shocked.gif and ride 2 up a bunch with my wife who is 120ish.
So, what pressures have you folks found to be the best?? (with rear tire off the ground)
I don't find any pressure to be neccesary. I'm slightly over 200 my wife is about 150. It seems like #1 on the shock setting is still stiffer than #5 was on my shadow.
I'm confused on what the difference is between the settings and the additional air? Does the added air just supplement the 4 settings or does one affect compression stiffness and the other for rebound pressure?
Seems like too much hassel unless there is any easy way to get the tire off the ground. If you do it on its side stand wouldn't the pressures be off due to more weight leaning on the left side?
Yes, its a hassle...have to get wife or one of the kids to help steady the bike and had to rig a sort of jig like on a car frame machine to lift it..finally found it easier to just do on the ground and held upright by one of those volunteers mentioned earlier. Just read a few post on different sites that said it adds 3-5 lbs pressure from your pump reading.
My understanding is that the settings on the shocks are for rebound and the air pressure affects the compression..but I am asking the question here so I could definitely be wrong. Never really been able to tell a bunch of difference on mine playing with the settings on the shocks.
blowndodge
08-12-2007, 02:36 PM
No air pressure is for a single rider at about 170lbs. Since you a big boy like some of us, I'm 225lbs, I run 15psi and the damper on the second click. It still is a soft ride but it doesn't bottom out.
You have to keep two things in mind when your talking about shocks. Air and/or springs determine how much resistance to your suspension movement is allowed "load" . The compression and/or rebound setting determines the speed of that movement "load".
Your bike would ride like a pogo stick without the dampning effect. Once the spring compresses in a bump in the road if allowed to expand back to its original shape without something to slow that expansion "damper" effect you would bounce down the highway.
Think of the compression and expansion damping as oil passing through a series of holes. Largers holes allow the oil to pass quicker than smaller holes for obvious reasons. Thus largers hole allow the spring to compress and rebound quicker than smaller holes. This is what the 4 position clicker on your shocks do. It changes the size of the holes in the shock to either slow down or speed up the movement of the "load"
Make sense???
So the air adds more resistance to the downward suspension movement and the 4 clicks change the speed of the rebound?
Mine seems to ride nice on #3 with no air single or 2-up
A chart would be nice to show ideal settings for any given weight.
Is it a comfort thing or safety? It seems like too much air for the load would make it more hardtail like possibly causing the rear tire to bounce off the ground if you hit a nasty bump?
blowndodge
08-12-2007, 05:50 PM
You got WM! Ideally for a cruiser rider wanting the most compliant ride you would add enough air to the riding situation to just stop short of bottoming out. Bottoming out, by the way, is harder on your shocks that you realize. Seals that contain that air take a beating becaue your hitting the stop inside the shock and its beating the heck out of the inside of the air bladder.
Many have thought that stronger damping with softer spring/air is the key but that can be overdone and let me explain:
Air inside the shock acting like a spring is compressed, the air is compressed and the resistance starts to increase. Mathmatically if you compress the shock one inch, the second inch takes twice as much to compress and the third inch takes twice that. It's ever increasing exponentially.
This is because air is compressible, remember it's how we inflate our tires. The oil inside the shock however is not. Liquid doesn't compress at all. Thats why liquids blow up in your freezer and why glaciers rip mountains apart.
Reducing the oil flow through the holes in the damper (1 to 4 ) makes the "speed" slower and you can "over damp" the shock and set it at no air pressure but too much damper and it won't let the shock compress fast enough and the ride will feel like you have 40 pounds of pressure in them. The oil will only move a certain speed through the holes because liquid (oil) is not compressible.
I had been on II rebound and no air...a little "bouncy" on rough roads....put 20lbs in today..cause me and wife scare the H&LL outta 400 lbs..mostly me in case she reads this. Rode very nice..stayed on II for rebound. I tried to hit every dip and road patch I could find and it never approached a bottom out situation. Maybe just a tiny bit stiffer...I am going to back them down a couple pounds at a time and see how that works.
By the way...If anyone intends on doing this, make sure to use a suspension pump (about $40). I takes very little air to make 20lbs pressure..high pressure would damage the shocks and you could never get accurate pressure with a standard bicycle pump.
It gave you a scare? Elaborate if you could....
dogdoc
08-13-2007, 08:01 AM
Ihave never checked my air in my shocks but run the setting on ll and it was fine even 2-up. Then I added V&H bagger pipes and when I pulled out of the drive with the wife, it made a scrapping noice(bottomed out), thought it was the baffle scres but they looked clean. Might have been the tire hitting inside of fender? I set number to lll and seems better for 325 lbs of riders. Thought you could use any low volume pump(I.E. bike pump)??
Doc
I run mine the same as Wolfman....#3 and no air in the shocks. Never had any problems.
Sorry Nico...I should have been more clear....
I meant that the wife and I scare the h*ll outta 400lbs when we are both on the bike....no scares on the ride..just a little stiffer ride...I barely noticed and the wife said she thought it was the same.
I too have scraped the V&H baggers with 2 up and need to replace one of the bolts that holds the baffle in. I tend to lean the Nomad over to its limits sometimes though ;)
Ahh... Good to hear you didn't have a scare on the bike.... whew~~
Doc,
A bike pump will put air in the shocks fine..but you will lose some pressure when you take the connection off of the schrader valve..then when you check it with an air guage you will lose a little. It takes such a small amount of air that this can make a difference and you can have really different pressure on one side vs the other.
The suspension pumps do not allow any air to escape when you disconnect and you can be precise with each shock..or you can install the equalizing system I have seen on Gadgets page to make sure they are equal.
I had mine bumped up druing break-in service since I'm not my mother's smallest child, and the fact that I didnt like bottoming out riding two-up. Shop told me they put about 50% of the max air charge in and I havent bottomed out again. I switch the damper to the 3rd setting for riding two-up.
toxictavrn
08-14-2007, 12:50 PM
dang!!!! i run 50psi in my rear shocks with me and my girl and cargo, i figure 450lbs weight or so, i dont know how in the world you can run on no air pressure in the shocks! i d be dead!
Total weight 2 up 420 lbs. 36psi at 4 is very smooth. It took a lot of trial and error.
Excellent...Another man of my...uuhem...stature!!! :-/
:-/
I will give it a try..right now the 20lbs seems to work but have not been to the mountains on it yet.
davidjones1
08-14-2007, 09:16 PM
Hi, new to this site, really like the info, I do have a question is it the lower the number the siffer the ride or is it the other way around.
Had been riding mine on level 2...... lowered it today to 1 to see how it was.... felt like I was in a cadillac with worn shocks.... raised it to 3 and it's nice and stiff... I'll leave it there.... smoothe.... I have no idea how much air I have in there... ::)
blowndodge
08-14-2007, 10:11 PM
Nice and stiff huh? Gee, couldn't have said something like "ride feels more controlled". Nice and stiff..
Freudian slip...................
Been spending too much time on the "BABE" thread huh Nico!?!?! That'll get you the 4 setting :)
socwkbiker
08-15-2007, 12:17 PM
Get you there in a hurry too.
Well, I finally decided to check the air pressure in my rear shocks.... had 22 psi in the right one and 12 in the left...... took a TINY bit out of the right one and it went down to 10 psi !!!!! So............... like an idiot, I decided I could take out a miniscule amout out of the left............. it went to 8 psi !!!!!!! I left it alone for now.... geez...SUPER sensitive.......
Yep, doesnt take much to change it which is why you need that susupension pump..ask around before you buy one...you probably know someone close to you with one that you can use..if not, and this is going to be HARD to beleive, HD shops sell em for $39.99...cheaper than online....and you will have something with that pretty little emblem on it (scratched mine off http://s2.images.proboards.com/cheesy.gif http://s2.images.proboards.com/cheesy.gif http://s2.images.proboards.com/cheesy.gif
No chace with a bicycle pump??
I couldnt make it work to balance the two...you lose some when you disconnect and when you check the pressure since it takes so little to air loss to change...although sounds like you didnt have to much problem with the two unbalanced. You might have better luck than me.
Yeh.... it's so sensitive I know you're right about getting the good pump.... I couldn't believe one little Pshhh... and went from 22 to 10 psi just like that.... so maybe I'll make it a half day project to save $40.. and drive myself crazy.... then still get the good pump after I frustrate myself to death!! lol Thanks for the help Toddster..... 39 more posts and you too will be reach wacky staus!!! :)
Nico
We can meet 1/2 way and you are welcome to use mine....say somewhere in Arkansas??? http://s2.images.proboards.com/grin.gif http://s2.images.proboards.com/grin.gif http://s2.images.proboards.com/grin.gif
<marquee> http://s2.images.proboards.com/shocked.gif</marquee>
blowndodge
08-15-2007, 05:34 PM
That doesn't count as a post. TRIP!!!! Two star Postitho reduction!!!
<marquee> http://s2.images.proboards.com/shocked.gif</marquee>
http://s2.images.proboards.com/cool.gif http://s2.images.proboards.com/cool.gif http://s2.images.proboards.com/cool.gif http://s2.images.proboards.com/cool.gifWe are meetin in Arkansas on Saturday to add 2 lbs to Nico's shocks.... http://s2.images.proboards.com/cool.gif http://s2.images.proboards.com/cool.gif http://s2.images.proboards.com/cool.gif Anything to save a Madder 40 bucks.
blowndodge
08-15-2007, 11:00 PM
You ought to see him try to put gas in his tank! He goes to the full service isle....
They're hard to find, but they do lay out the red carpet.......
D*mn.. just realized I had the bike on the side stand when I checked it....... now it's REALLY off!!!
http://i170.photobucket.com/albums/u272/DrNickDC/SMITE.jpg
socwkbiker
08-16-2007, 08:52 AM
Last night I changed the setting from 2 to 1 and did notice a difference in the ride. So, to simplify this mess, the lower the number, the firmer the ride, correct?
flightdoc
08-16-2007, 09:09 AM
My wife works for a sporting goods company and she bought me a bicycle pump for the rear shocks. The pump has a special valve on it so it does not allow air to escape when removing it. It's supposed to be a high end pump. I've seen it advertized by motorcycle suppliers at 2x the price. I'll find out the manufacturer and pass it on to you all.
Also, it is a pain in the a** to get the bike off the floor. I purchased a floor/auto jack from sears. I have to drive the bike up onto 2 pieces of 1/2 inch boards to get it up high enough for the jack to fit under it.
Last night I changed the setting from 2 to 1 and did notice a difference in the ride. So, to simplify this mess, the lower the number, the firmer the ride, correct?
The fatter you are, the higher the number. (per the manual)
yeh... When I had it one #1... it floated (soft)... went to #3 and stiffer.... or however BD put it..... lol
blowndodge
08-16-2007, 11:16 AM
I didn't put it anywhere???!!
Nice and stiff huh? Gee, couldn't have said something like "ride feels more controlled". Nice and stiff..
::)
blowndodge
08-16-2007, 11:38 AM
Flew right by you did it??? LOL
socwkbiker
08-16-2007, 11:42 AM
Crap, do they have a setting of 20?
<marquee><-----------------------Woosh............................</marquee>
flightdoc
08-17-2007, 07:59 AM
Here's a link to the pump I mentioned the other day.
vin
http://ecom1.planetbike.com/1031.html
Thanx Doc!
http://i170.photobucket.com/albums/u272/DrNickDC/BIKER1.jpg
If they make one that only measures up to 60psi you might want to try that one..since the max pressure in your shock is around 43lbs (I think if I am remembering..out of town traveling this week)....just a little easier to get precise with the larger increments. Bicycles use much higher pressure.
After messing with it, I have about 8 psi in each one and I've got it set to #3 with 40psi in the Dunlop 404 and it feels great!
blowndodge
08-17-2007, 09:10 AM
After messing with it, I have about 8 psi in each one and I've got it set to #3 with 40psi in the Dunlop 404 and it feels great!
Yea, but what about the bike??? ::) ::) ::) ::)
blowndodge
08-17-2007, 11:37 AM
ZOOOOOOOOOOOOMMMMMMMMMMMMM Feels great. Less filling feels great, less filling.
ponch
08-18-2007, 05:12 PM
RTFM. The owners manual has a chart.
So the air adds more resistance to the downward suspension movement and the 4 clicks change the speed of the rebound?
Mine seems to ride nice on #3 with no air single or 2-up
A chart would be nice to show ideal settings for any given weight.
Is it a comfort thing or safety? It seems like too much air for the load would make it more hardtail like possibly causing the rear tire to bounce off the ground if you hit a nasty bump?
flightdoc
08-20-2007, 09:03 AM
I thought the rear shocks took a max of 20lbs
I thought it took up to 40... but I'll check my manual...
"And what pressure? The good news is you need to go for a ride (take the pump with you). Ride the roads you normally enjoy traveling on. Are they billiard board smooth? You'll need little or maybe zero pressure. Got dips? You'll need a bit more. Got potholes? A lot more. Speed bumps are the worst. If any of these things cause your bike to bottom out at speeds you'd normally hit them at, put in some air. If you generally ride two up be sure and do this test with your passenger. When the bike doesn't bottom out any more under the most severe test you expect to give it you've found your pressure. Remember if you're on a trip carrying more than the normal amount of gear you might need to add a couple of pounds. Never exceed the manufacturers suggested 43 pound maximum."
by Gadget
dogdoc
09-21-2007, 04:56 PM
Thx Todd, So far Im riding no air and setting on 3 or 4 and working fine with 2 up riding.
Generally, 20lbs, rebound on 2. Set rebound to 3or 4 two up. Now, if I load the bags and the rack and go two up 40lbs.
bobzinger
09-26-2007, 10:08 AM
1 up at 280lbs I have 20psi, set on II (bike level sitting on ground).
2-up with gear (we're pushing 530lb) 30psi, set on III
ringadingh
09-26-2007, 11:55 AM
I rin mine at setting #3 with 35 lbs of air, cured the bottoming out and rides much better than no air at all.
spork
09-26-2007, 03:24 PM
If anyone is in the Houston area and wants to use a suspension pump, I have one and my shop is always open.:)
I will also bring it to the Rally in ES so we can use it then also if needed.
I was just given the Motion Pro pump by a former Classic owner. He apparently has no need of it with his new Concours 14.
Here's a link to the pump I mentioned the other day.
vin
http://ecom1.planetbike.com/1031.html
That's a good price. I paid more than that for the Progressive brand, and it looks to be the same thing. Also heard, Harley sells a progressive pump (with their label) for less than Progressive.
flightdoc
09-27-2007, 07:51 AM
I'm confussed about the max air pressure for the shocks. I don't have access to my owners manuel for anopther 2=3 weeks. Could someone look it up for us? I was definitley told that 20lbs was the max pressure. I'd love to know and sure many of us need to know.
Top Cat
09-27-2007, 05:04 PM
My 2007 manuel says 43 psi is max.
oldmanriver
09-28-2007, 09:59 AM
2005 my manual says 43 lbs also is max.
flightdoc
09-28-2007, 01:09 PM
thanks guys
"i run 50psi in my rear shocks"
I believe 43 is the max that should be put in the shocks. Per mom.
spork
10-01-2007, 06:32 PM
I just wanted to thank you all for the information in this thread. This is why I love this type of environment. Great knowledge floating around in this place.
I checked the shocks and they were at 2 pounds a piece. I thought there was nothing wrong with the ride with shock setting at 3 when solo and 4 when taking a trip and loaded down. I just went to shock settng 3 and 26 pounds in wach and this thing is like a totally new ride. I can't wait to get it out on the road and see if some of the pogo stick effect resolves in the corners.
Thanks!
flightdoc
10-02-2007, 03:40 PM
thanks for the info gang
"And what pressure? The good news is you need to go for a ride (take the pump with you). Ride the roads you normally enjoy traveling on. Are they billiard board smooth? You'll need little or maybe zero pressure. Got dips? You'll need a bit more. Got potholes? A lot more. Speed bumps are the worst. If any of these things cause your bike to bottom out at speeds you'd normally hit them at, put in some air. If you generally ride two up be sure and do this test with your passenger. When the bike doesn't bottom out any more under the most severe test you expect to give it you've found your pressure. Remember if you're on a trip carrying more than the normal amount of gear you might need to add a couple of pounds. Never exceed the manufacturers suggested 43 pound maximum."
by Gadget
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