Air pump problems

[gunner]

2020 RTL was riding stiff like the rear suspension wasn’t absorbing bumps.

1. Jumped up and down on trailer hitch, very little movement, measured distance from hitch to floor 12”.

2. Checked psi in bladder 51 lbs.

3. Emptied bladder to O psi measured distance from hitch to floor 13 1/4”

4. Started bike, let it run 5 minutes shut it off and checked pressure 0 psi.

5. Still at 13 1/4”.

Any suggestions? Thx

[bikerchris1270]

2020 RTL was riding stiff like the rear suspension wasn’t absorbing bumps.

1. Jumped up and down on trailer hitch, very little movement, measured distance from hitch to floor 12”.

2. Checked psi in bladder 51 lbs.

3. Emptied bladder to O psi measured distance from hitch to floor 13 1/4”

4. Started bike, let it run 5 minutes shut it off and checked pressure 0 psi.

5. Still at 13 1/4”.

Any suggestions? Thx

Recheck with engine running, foot on brake, place it in gear, park brake off….no warnings on dash…..wait 30 seconds.
Also check that actuator arm is attached to height sensor and rear suspension arm.

[Peter Aawen]

When you let it run for 5 minutes, did you have it in gear with the Park Brake OFF, did you? .

The air compresor in the ACS won't run if the Spyder's not running, in gear, & with the Park Brake off - and even if all that is in place, many (if not all?!) Spyders with the manual AND automatic ACS (ie, those Spyders that also have a 'Hard/Soft' switch that lets the operator add or release air pressure in addition to the Auto Pre-set system) will report a fault & flash 'Manual' whenever the switch is activated on an empty air bag - apparently there NEEDS to be some air in the air bag or the system will report a fault & call on the operator to manually add some air pressure to the Air bag, just to be sure, to be sure!

As for the change in height of the hitch - if it's an OEM Hitch, then the hitch itself is fixed onto the end of the swing arm, so the air pressure that will vary it's height the most will be the pressure in your Spyder's rear tire! . The change in height you measured as described above will most likely be due to the pivot point end of the swing arm on the frame (ie, the other end of the arm to the hitch... That swing arm pivot end is the end holding the frame & weight of the Spyder off the ground by the wheel & axle & the air pressure in the tire ) going DOWN as you emptied the air bag. The height variation you saw at the hitch end was the swing arm/hitch assy acting as a simple lever (ie Load on one end; Fulcrum being the axle in the middle under the Lever; Force pushing down on the other end to the load... ) with the 'Force' in this case being the weight of the Spyder pushing down on the Swing arm pivot end; the Fulcrum being the axle held off the ground by the wheel & tire air pressure somewhere in the middle of the Swing arm/hitch assy, aka the Lever's total length; and the Load end (ie, the hitch) being raised as the Force pushes the other end of the Lever (at the Swing Arm end) Down! Juuust like a see-saw/teeter totter - one end goes Down, the other end goes Up cos the Fulcrum is innthe middle!

In your case gunner, as you've described above, the hitch height change is pretty much exactly what you should've expected by measuring the hitch height; and I suspect the issue with the compressor not running is that you didn't have the Spyder running, in gear, and with the Park Brake OFF... this catches everyone at least once!

So I'd suggest that you measure height changes on some other part of the body or mudguard, somewhere that's carried by the suspension, not anywhere that's carried only by the wheel, and that you start with at least 10 psi of air in the bag. Start by adding some via the Schraeder valve under the seat if necessary and checking the air bag pressure with an independent gauge so that you know what it is/it's at least 10 psi; measure the 'suspension carried body height' as outlined; and then go for a ryde of a few hundred metres or so before coming back to your start point & returning the Spyder to it's original position; where you should re-measure the body height and the air bag pressure. THEN tell us what you've found...



Edit: Sorry chris, I didn't check for any replies made while I was drafting mine, which ended up taking a fair bit longer than originally expected due to unavoidable interruptions.

[Peteoz]

Actually, Peter, I just put a KOBO reader on my shraeder valve to check the difference in pressures on my ‘21 RT. Sitting unstarted, it was around 62 psi. I then started the RT and climbed aboard, still in neutral, and it climbed to 75psi. I then put it in gear and headed out on the road, and about 1km later, my FOBO warning went off as it had reached 82 psi. The ‘20+ RT may behave differently to what it used did on earlier models.

Gunner, park your RT about 4’ from a wall and start the Spyder without you on it. Mark the top of the headlight beam on the wall. Sit on the rear seat of the Spyder and you should see the light beam rise above the wall mark. Within say 10-20 seconds max, the beam should come down to your original mark, if the auto pump is working correctly. It is not a big jump on the wall, maybe only 1/2 to 1”.

Pete

[Peter Aawen]

Actually, Peter, I just put a KOBO reader on my shraeder valve to check the difference in pressures on my ‘21 RT. Sitting unstarted, it was around 62 psi. I then started the RT and climbed aboard, still in neutral, and it climbed to 75psi. I then put it in gear and headed out on the road, and about 1km later, my FOBO warning went off as it had reached 82 psi. The ‘20+ RT may behave differently to what it used did on earlier models.

.....

Pete

Not sure that your reasoning actually holds true Pete....

Consider this.... Your air bag, which started out containing 62 psi of air, sits between the swing arm & the frame ahead of the shock, and it's meant to be the shock & spring that actually carries the weight, right?? So it was holding that 62 psi before you started it & sat on it, then after you started your Spyder and sat on it, which would've compressed the shock and the spring and also the air bag, the air bag pressure went up to 72 psi.... aaand I'd suggest that's exactly what it should do even if you HADN'T started your Spyder!! . By adding weight to the load, enough to compress the spring & shock even just a little, means it also hasta compress the air bag a bit, doesn't it?? . If I recall the few things I know about all these laws & stuff that they call physics properly, if you compress a given volume of gas into a smaller volume, then you've increased it's pressure.... isn't that right?! . So it doesn't matter what the Spyder engine is or was doing, if the air bag is holding air & already under pressure when the Spyder's unladen & not running, then regardless of anything else, the air bag pressure MUST increase when you (or anyone else) climbs aboard said Spyder cos it's ride height & therefore the air bag is going to be compressed by the increased load!

And then the air bag pressure increased even more once you put it in gear & started ryding it . I'd suggest THAT second increase was due to the compressor working exactly as I described earlier and because you put it in gear & turned the Park brake off, it started adding air to the air bag in an attempt to maintain the preset ryde height under the dynamic load you & the weight of the Spyder put on it while ryding... only it took a km or so to do that, after all, it's only a little compressor. So that too fits with what you should expect if everything works as I explained earlier, right?! Clear as mud, isn't it?!

Anyhow, I'm not convinced that anything has actually changed for the ACS on the 2020+ RT's Pete Not yet, anyway....

[gunner]

Thanks everyone who responded, I’ll do what was suggested 1st think in morning and get back to you hopefully with good news.
Do you have any thoughts on why it’s riding like a Buckboard.

[Peteoz]

I’ll take your word for it, Peter. I’ll need a coffee before I try to digest that ��

Pete

[Peter Aawen]

Thanks everyone who responded, I’ll do what was suggested 1st think in morning and get back to you hopefully with good news.
Do you have any thoughts on why it’s riding like a Buckboard.

What tires are you running?? Are they still the OE Kendas?

Due to their lighter construction than any other car tire, the OE Spec Kendas & any of their clones (Kanines, Arachnid etc) will need at least the pressures shown on your Tire Placard, just to carry the load of the Spyder, and you pay the penalty in the ride, traction, & handling, et al!

But if you're running 'proper' car tires (ie, any other brand of car tire with a higher load &/or speed rating and the stronger construction necessary to carry a normal car, which is a significantly heavier vehicle ) then they are made a fair bit stronger than the Kendas/clones so you don't need to run pressures that high & you shouldn't - you'll get a much better ride & improved traction, handling, wear, etc by running non-OE car tires at 16-18psi.

[Snowbelt Spyder]

If I may...

Gunner - seems like everything is working as designed. Go out and look at the trailer hitch again. Unlike your pickup truck, the Spyder trailer hitch is not mounted to the frame - it's bolted to the rear axle, which is attached to the wheel, which is attached to the road. So, of course there won't be any movement when jumping up and down on the trailer hitch, because it's not a suspended component.

If your "buckboard" issue is all about the trailer feeling every bump in the road, then yes, it will. That's because the trailer hitch is also going to feel every bump in the road. It's just the way it's designed.

Your butt is attached to the seat which is attached to the frame and IS a suspended component. Jump up and down on the seat, instead. Or more easily, put the 50# back in the air bladder, and while you sit in the seat, have your helper bounce the rear suspension with the passenger handles. It should work normally. You measured pressure at 50#, which is quite normal for air pressure for a single rider of average weight. And, gives indication that your air pump is working, otherwise you would not have had any pressure when you checked. Take it out and ride it around again for a few minutes, and then immediately measure air pressure. If it returns to around 50#, and you are of average weight, then it's working. Your Spyder automatically adjusts the air pressure in order to maintain a pre-programmed ride hight as the weight on the suspension changes.

So, if your "buckboard" issue is about the feeling in your butt, then you'll have to decide if it is bottoming out or measure the air pressure to see if it is over-inflating and have it looked at under your warranty. But, just to repeat, your trailer hitch has nothing to do with your suspension.

[Mikey]

Gunner if your bike is riding like a buckboard like you say it is then maybe you need to take it back to the shop and have them put it on BUDS and make sure that the limits have been set the way it's supposed to be. The problem with computers is its garbage in and garbage out, and if someone slipped this is what you get!! It's a new bike, use your warranty!!! You payed dearly for it!

[gunner]

Peter I did exactly what you said this morning. I added air, 15psi to bag, measured mud flap to floor 5 3/4” started the bike let it run for 5 min. in gear, E- brake off, then went for ride. When I returned the flap measured 6 1/2” from floor and pressure in the bag was 37. For clarification I only weight 135 lbs. When the wife gets home from work this evening I’ll have her take me for ride and see if the air pressure in the bag goes up with her, she weights 115 lbs. Does this sound right so far?

[gunner]

What tires are you running?? Are they still the OE Kendas?

Due to their lighter construction than any other car tire, the OE Spec Kendas & any of their clones (Kanines, Arachnid etc) will need at least the pressures shown on your Tire Placard, just to carry the load of the Spyder, and you pay the penalty in the ride, traction, & handling, et al!

i
But if you're running 'proper' car tires (ie, any other brand of car tire with a higher load &/or speed rating and the stronger construction necessary to carry a normal car, which is a significantly heavier vehicle ) then they are made a fair bit stronger than the Kendas/clones so you don't need to run pressures that high & you shouldn't - you'll get a much better ride & improved traction, handling, wear, etc by running non-OE car tires at 16-18psi.

Peter I’m running on back General Altimax RT 43 215/60 RT15 17psi
Front Vredesten Quatrain 175/55 R15 16ps

[Peter Aawen]

Peter I did exactly what you said this morning. I added air, 15psi to bag, measured mud flap to floor 5 3/4” started the bike let it run for 5 min. in gear, E- brake off, then went for ride. When I returned the flap measured 6 1/2” from floor and pressure in the bag was 37. For clarification I only weight 135 lbs. When the wife gets home from work this evening I’ll have her take me for ride and see if the air pressure in the bag goes up with her, she weights 115 lbs. Does this sound right so far?

Given that you both are pretty light & barring anything else really odd going on with your shocks/springs etc, it does sound as tho things in the ACS are working the way they should.... possibly you could try dropping the rear tire maybe another psi or 2 to try & improve your ride further, but you really don't want to go any lower than 14-15 psi in the rear - nor much lower than the pressures you've currently got up front!

Maybe you could try 16 psi in the rear Altimax, just to see if it'll soften the ride just a little more, but if it's really that harsh at 17psi, you'd hafta think something else besides the ACS &/or the tires was wrong... have you tried loading it up as much as you can & seeing if that makes a difference?? Or compared your tire pressure gauge to anyone else's/another one?? Could it be that your gauge is out a bit, & reading more than just a psi or 2 lower than actual??

Those possibilities aside, I'd hafta add to what others have said, & suggest that if you're still getting a really harsh ride on those tires running pressures low enough that they SHOULD make it ride better/softer, less harsh, give you greater traction, longer wear etc, & DO do all that for everyone else running them, then it's probably time to use that warranty & get your Spyder properly checked out! And if the dealer/tech has no idea but toes the BRP line anyway & says "it's the non-OE tires" cos that's what his script says, tell him to stick that BS in his pipe & smoke it, & then come up with something useful instead of parroting over-ripe BS at you; cos no pnuematic tire gives a harsher ride as its pressure is reduced; they don't work that way & never have, not once in the last 150 years or so since they first got put on a vehicle, probably never will either; & haven't done that for any of who knows how many users of auto tires on Spyders, nor for any one of all the millions of users of pnuematic tires on other vehicles besides!

Sorry I can't offer more atm, not from here in Oz anyway; so it's over to you... Good Luck!

[gunner]

Thanks Peter and everyone else that helped.

[Peteoz]

Not sure that your reasoning actually holds true Pete....

Anyhow, I'm not convinced that anything has actually changed for the ACS on the 2020+ RT's Pete Not yet, anyway....

Ahhhhhh yes. That makes complete sense, Peter. I stand corrected. I didn’t think of the compression of the airbag once I applied my lightweight frame to it. I will try checking the psi if I sit on the RT without even starting it, which should provide the same initial increase……just for info…..Thanks.👍

Pete