compressor leaks question

[Pineywoods36]

Over the last month I have noticed the compressor seems to run more often than I ever notices before, what is the best way to test for leaks?

 

[Highwayman2013]

It's usually the air bag, lots of soapy water will help.

 

[Roadster Renovations]

I used a bunch of soapy water and was unable to find the leak until after I removed the airbag and bench tested it.

 

[Pineywoods36]

I used a bunch of soapy water and was unable to find the leak until after I removed the airbag and bench tested it.

I am guessing there is a youtube video on air bag removal?

 

[Roadster Renovations]

I am guessing there is a youtube video on air bag removal?

This deals with the compressor replacement, but it gets you right where you need to be.

 

[oldguyinTX]

My dealer tells me that 99+% of the time the leak is either in the fittings or associated hoses/tubing. In fact, my bag is the only one he has ever replaced, and he's been a Spyder dealer since day one.

 

[2dogs]

Does anyone here understand the airbag function

I've had real issues with the air bag system on my 14 RTS SE6. After quite some time the dealer's service dept. removed the entire system and found a leak in the bottom of the bag. The bag was replaced and soon after, I purchased and installed the FOBO system. I placed one sensor on the Schrader valve under the seat to monitor the airbag pressure. I prefer to ride one up at approx. 35+ or - a little bit. That setting is generally the second one up from the bottom setting on the dash scale. Once set at that position the FOBO shows the pressure ranges from about 24 psi. to 57 psi. which makes the cornering at highway speeds a little interesting. Riding two up the pressure ranges from about 50 psi. to 85+ psi. and above. The FOBO alarm goes off at 85 psi because that it's the max pressure limit. So, what the pressure actually is I have no idea. I was told it was the ride height sensor that controlled the airbag pressure, not the other way around. I had a conversation with Steve at BRP and he said he didn't have an answer to the true function of the air bag, and he'd have to confer with one of the techs. I've not heard back from him in quite some time. Does anyone have any input as to how the airbag is supposed to actually function. I believe I'd prefer that it stay at one constant pressure which would make cornering a more consistent experience. By the way, my airbag bleeds out to 0 psi. over night. Is that normal? Thanks for any input anyone may have.

 

[Peter Aawen]

2dogs (nice username, that one, significant in any way??) Just about all air bags under vehicles will vary their pressure as the load & cornering forces change during operation, it's a function of the loading & height changes that occur as you ryde (& which must occur for proper suspension operation!) between the frame & the swing arm, which are the top & bottom mounting points for the air bag!! So you aren't gonna be able to get a 'constant pressure' air bag in there unless you disconnect & isolate it from one or both of those, & if it did remain at a constant pressure, it'd defeat the purpose of it being there!! This pressure increase during cornering is to your advantage tho, the increased pressure under cornering forces should help stop the rear squatting or lurching up & down as it would if it was just a constant pressure balloon fitted under there!! All this means is that it's true that the air bag works to maintain ride height & responds to changes in the ride height rather than trying to remain at a static pressure - in fact, it's pretty near impossible for an air bag used this way & installed this way NOT to vary it's pressure as you ride, & the 'piston' that the air bag sits on is designed & shaped just a little in order to limit any adverse effects on your ryding as you corner etc.

So what exactly is it that makes you think the air bag its pressure changes are what's making your cornering at hwy speeds interesting?? How are they interesting?? The bag & piston have been designed & tested not to make things interesting during cornering (despite the pressure changes which do & actually must occur) when they are functioning correctly; so if you are getting exciting events occurring as you ride & the air bags are functioning correctly as you've described their behaviour to us (apart from bleeding out overnight - that does suggest a slow leak somewhere) then there is probably something else wrong?!? Could be wheel alignment (& by that I mean not just toe in/out, but also camber & caster & all those other things that go into 'proper' wheel alignment on this sort of suspension!); could be failing DPS (Dynamic Power Steering)or a weak/dying battery causing the DPS to drop out every now & then; could be worn or loose components, A arm bushes, ball joints, tie rod ends, wheel bearings, etc; could even be dud shocks or springs.... Spyders are renowned for having 'interesting' steering, straight line tracking, & cornering straight out of the box &/or if they haven't had a good wheel alignment done (has yours?)

We really need a reasonable description of why/what it is that makes your cornering interesting before dissecting the ACS & compressor, it might be something else entirely!! :thumbup:

 

[2dogs]

2dogs (nice username, that one, significant in any way??) Just about all air bags under vehicles will vary their pressure as the load & cornering forces change during operation, it's a function of the loading & height changes that occur as you ryde (& which must occur for proper suspension operation!) between the frame & the swing arm, which are the top & bottom mounting points for the air bag!! So you aren't gonna be able to get a 'constant pressure' air bag in there unless you disconnect & isolate it from one or both of those, & if it did remain at a constant pressure, it'd defeat the purpose of it being there!! This pressure increase during cornering is to your advantage tho, the increased pressure under cornering forces should help stop the rear squatting or lurching up & down as it would if it was just a constant pressure balloon fitted under there!! All this means is that it's true that the air bag works to maintain ride height & responds to changes in the ride height rather than trying to remain at a static pressure - in fact, it's pretty near impossible for an air bag used this way & installed this way NOT to vary it's pressure as you ride, & the 'piston' that the air bag sits on is designed & shaped just a little in order to limit any adverse effects on your ryding as you corner etc.

So what exactly is it that makes you think the air bag its pressure changes are what's making your cornering at hwy speeds interesting?? How are they interesting?? The bag & piston have been designed & tested not to make things interesting during cornering (despite the pressure changes which do & actually must occur) when they are functioning correctly; so if you are getting exciting events occurring as you ride & the air bags are functioning correctly as you've described their behaviour to us (apart from bleeding out overnight - that does suggest a slow leak somewhere) then there is probably something else wrong?!? Could be wheel alignment (& by that I mean not just toe in/out, but also camber & caster & all those other things that go into 'proper' wheel alignment on this sort of suspension!); could be failing DPS (Dynamic Power Steering)or a weak/dying battery causing the DPS to drop out every now & then; could be worn or loose components, A arm bushes, ball joints, tie rod ends, wheel bearings, etc; could even be dud shocks or springs.... Spyders are renowned for having 'interesting' steering, straight line tracking, & cornering straight out of the box &/or if they haven't had a good wheel alignment done (has yours?)

We really need a reasonable description of why/what it is that makes your cornering interesting before dissecting the ACS & compressor, it might be something else entirely!! :thumbup:

The handle 2dogs is a hold over from the days of CB radio, which no longer exist I guess because of cell phones and Bluetooth. Anyway, the interesting part of cornering is after riding two up for a while the spyder becomes, how could I explain it, soft and squashy in the turns. Not solid and firm. Particularly in corners at the end of long straight a-ways. Checking the FOBO readings for airbag pressure prior to entering corners at the end of straight a-ways, show inconsistent readings from the low 50's psi to 85 psi. When riding one up it doesn't seem to very pressures quite as much or quite as often. The folks from Los Vegas did my alignment and I have Ron's sway bar with spring stiffeners on the front shocks. (Total miles now are around 18k.) All that and a little less throttle seems to have helped things immensely. Prior to those up grades I felt as if I was riding a marshmallow at times. Currently the interesting feeling comes in just about at, or prior to the apex of the turn. I guess I'm just used the having a non-self adjusting suspension. If the airbag would remain at a constant preset psi, life aboard a RTS SE6 would be much more pleasant; from my point of view that is. By the way Peter thanks a bunch for response. Hope I answered some of your questions.

 

[Peter Aawen]

It certainly did answer a few of them 2dogs! :thumbup: But as always, answering one lot really just creates a whole heap more questions! :shocked:

First up, what sort of spring stiffeners do you have? Could be irrelevant, but if they are 'bolt style' stiffeners rather than full coil dia tension/pre-load adjusters, that might not be a great thing!! Come back to that later, but still, from what you are telling us, it really sounds to me like it's your shocks that are going off & making things feel 'soft and squashy in the turns' rather than being solid and firm!! I might clarify just a bit on my background before I go too far ahead, just to help explain to you where what I'm suggesting is coming from - I've done a lot of professional vehicle & tire testing over the years, including testing full air-bag replacement suspensions & air-ride/height adjustment systems, so while my opinion here is largely speculation, it is vaguely educated speculation (still only worth the paper it's written on tho, there's a whole lot of guessing & assuming about your specific issue going on here - so read it & do with it as you will, & at your own risk of course! pps: )

Anyhooo - Rear suspension air bag pressure will naturally reduce while you are braking at the end of a straight - the vehicle loading/weight transfers forwards onto the front wheels under braking, lifting the rear suspension & taking the weight off the rear tire, & the air bag & shock/spring, stretching them out a bit larger in fact; but then as you get off the brakes & back onto the throttle, the front wheels/suspension unload, the weight squats back onto the rear tire & then loads up outside front wheel as you steer thru the corner, & the air bag pressure goes up! How steady you are on the throttle & steering thru the corner will govern how steady the air bag pressure is thru the corner, small changes in steering angle OR throttle will vary the loading on the outside front wheel & the rear wheel, so the air bag pressure will vary as that occurs & as the suspension reacts to road surface irregularities too - but the volume of air in the bag will not usually change much at all while all this is going on, and it sounds like it's all happening the way it should!! Unless of course your air compressor is hammering away while all this is going on, but then they don't usually make any significant changes while this sort of thing is happening anyway - yours isn't, is it?!

So from what you've told us so far, I suspect your air bag is working OK & your concerns should be directed elsewhere! It could be your springs that are off, maybe they are not suitable for the loads you are imposing on them while you ride; and be warned, on other vehicles those 'bolt style' spring stiffeners have been known to put 'point load' stresses on the metal of the coil springs in a way that really isn't good for them (ultimately to the extent of breaking springs!!) &/or the coil spring's performance, so that could be an issue, altho I don't think a Spyder is going to be heavy enough to worry about them in the short/mid term; but seriously, because it comes on after a while & usually with a greater load aboard, it sounds like your shocks are fading due to over-heating &/or 'aerating' to the extent that as they are loaded up & then released, they aren't really doing much at all, let alone functioning properly!! So after a while the ride thru the corners feels 'soft & squashy' - I'd guess that if you stop for a long lunch the ride feels OK again for a while afterwards, but after ryding for a while & warming everything up, it once again starts to feel 'soft & squashy'.....

So on to more questions!! pps: How old are the shocks on your Spyder? What make/style of shocks are they? What type of Spring Stiffeners are they? Got any pics of them in/on the coils? Which year & model Spyder is it for that matter, & a rough idea on how heavy it all might be all up when this is occurring could help explain better & narrow it down to the true cause, be it shocks or air-bag issues. But over-all, given what you've described so far, I do reckon it sounds like your air bag is working the way it should & you are probably reading too much into the info your TPMS/FOBO is providing!! You should expect the Air bag pressure to drop as you brake at the end of a straight, then increase as you get back on the gas, vary somewhat as you corner & your suspension responds to the road surface & cornering forces as well as your gas & steering inputs, then it should all return to 'normal' once you straighten out again - altho even ryding straight & level will generally see some responses as the air bag reacts to your suspension absorbing road shocks & dropping into depressions etc. But by watching all this happen, you've been given a handle on something you don't necessarily understand fully so you end up worrying needlessly about the ride & the air bag, & maybe you are 'reading into it' things that aren't really an issue - there again, the soft & squashy feeling may well be 'shock fade' due to worn out, leaking, or over-heated shocks that have aerated the oil inside them & aren't working properly; or maybe it could be damaged, over-loaded, or over-stressed coil springs letting the ride wallow a bit. :dontknow:

Sorry about the essay (again...) but I reckon it's an interesting issue & worth trying to sort out, isn't it?? But please Zip, don't always hit the 'reply with quote' button & duplicate all my guff just to respond - I'm sure seeing it just the once is more than enough for most! The red '+ Reply to Thread' button is below & to the left.

 

[bmwlarry]

Be sure to check "under" the airbag itself. I got into some fresh chip seal, popped five holes in my belt & on replacement we found about 10 very sharp chips under the air bag that would have worn holes in the bag - eventually!

 

[2dogs]

Yes Larry, the first leak was under the airbag at the bottom where it attaches to the swing arm. A very small leak, and the airbag was replaced. Peter, the bike is a 14 RTS SE6 as I mentioned before, with 18k on factory front shocks. I bought rubber donut style Mr. Gasket brand spring spacers and installed one in each front shock coil spring. They only cost $7.00's and made a world of difference. Improved performance in handling by 50%. They did not raise the front end but took up the space between two coils eliminating about 1" of coil compression. After installing the spring spacers I installed the sway bar, which now made little difference. I removed the spacers and test rode the bike (one up) with just the sway bar, and again noticed very little difference. I reinstalled the spacers and now enjoy a rock solid front end feeling with both the sway bar and spring spacers together. Dodging surprise obstacles in the roadway now isn't quite as scary as it used to be. Seldom do I brake prior to entering a curve when riding like one should ride. I judge my distance and my surroundings and use engine deceleration to reduce my speed when entering a curve. I do not experience much load/unload on the rear suspension as if I were breaking to slow my speed. However, I know what you're talking about, loading and unloading the suspension using the brakes and throttle. You are correct regarding the FOBO and it's response time to accurate readings. I've paid close attention and when approaching a curve and the pressure reading on the airbag remains high, the G forces throughout the turn seem less than when the airbag pressures are low. The interesting part is not knowing what the given airbag psi is going into the turn. I do like the ability to adjust the airbag psi when I want to change it. I just don't care for the airbag changing it's self without me knowing it. Obviously I'm still alive so you know I don't press every corner to it's threshold. I don't ride like that anymore. Again, I would suspect that an adjustable rear (or any) suspension should remain at a preset until changed by the operator. When a suspension system changes it self without knowledge of surround conditions it makes for some interesting riding situations. IE; oop's I wasn't ready for that one! :yikes: Yes, I've been told the BRP oem front shocks are not the best and probably should be replaced ASAP with a more quality shock. And although I know you're aware but you didn't mention it, any outside influence to the rear suspension immediately transfers it's self to the front end, again making things interesting at times . I've owned bikes before that had air compressor adjustable suspension systems, but none of them adjusted themselves without operator input.