certainly makes for a richer learning experience
Who understands the PAIR system to know I can clamp it off, leaving it in place?
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OP
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moddy
the mod
I don't have a mechanical background. My first car in 1987 a 73 Volkswagen Super Beetle was either fixed by me or it wasn't fixed at all.
I've been in the soup for making a repair whether I had time or not, so many times I've lost count.
The modification is going well. I have the flatbar mounted on the bellhousing beads attached and am hydrating before I drill the crossmember for mounting the servo cable. It won't be long now before I can test ride. I got sick yesterday and I've had to take extra time so I don't know if I'll ride today just out of having pushed and pulled so many things on the bike.
John OoSTerhuis
Life Is Good!
WRONG! The vacuum side of the Air Suction Valves (aka PAIRs) is a sealed, closed system. That 'line'/hose splits and leads to both ASVs' vacuum chambers with a diaphragm on one side. These diaphragms in the valves are drawn up in their sealed chambers only during periods of high intake manifold vacuum provided by #2 and #4 intake manifold vacuum ports. This occurs during engine deceleration after quick throttle roll off and engine braking like downhill running.
When the diaphragms are pulled up, this cuts off the filtered air from the air box that is provided through the valves to the exhaust manifold constantly during normal operation. The valves are closed to prevent afterburn (what is mistakenly often referred to as backfiring) during the time excessive unburned hydrocarbons are being dumped into the exhaust.
Please see the diagram and description of the Secondary Air Supply System on page 1-33 in the Honda Service Manual. I have a picture somewhere of the valves, their diaphragms and chambers if that will help understand how this simple system works.
Edit: and as mentioned previously, please see how to test the ASV (applying vacuum) on page 5-17 in the Honda Service Manual. Additional clarification provided on page 7-8 in the Honda Common Service Manual.
John
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John OoSTerhuis
Life Is Good!
N.B. Read my tip in this picture's caption/text: http://www.st-riders.net/coppermine/displayimage.php?album=33&pid=833#top_display_media
OP
OP
moddy
the mod
Tip noted. Did the arm you installed on the bellhousing hit the tank until you bent it slightly away?
John OoSTerhuis
Life Is Good!
Short answer: no. There should be no interference in the CC's operation with this install method.
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OP
OP
moddy
the mod
Hmm, mine did. The bump on the front of the tank, '91 black model. My arm went straight down 1.25" from the bellhousing. Now, there wasn't a problem til after I'd replaced the tank and worked the throttle, then it scraped along the front of the tank at half throttle. At this point, to correct it with a different connection, I would have had to pull the tank OR put a 10° bend away from the tank. If the test ride doesn't prove successful, I will pull the tank and attach the beads differently.
I remember you referring to putting in a bend somewhere, it was probably the bracket for the servo cable to better align a straight pull to the bellhousing.
OP
OP
moddy
the mod
Not realizing what the clearance would be, I used the bolt the threads stop short, allowing there to be space between the eyelet that holds the beads. Had I known, I could have used a much smaller profile hardware. I could also just change it before I test ride. The more straight it is, the less work it has to do and that coincides with the trouble I'm having. I may even have to install a relay to ground, like others have done, I have a small amount of voltage, 125mv, in the brake wire that disengages cruise...but, one thing at a time. If the relay was the issue, it wouldn't have stayed engaged for up to a minute long.
John, do you think it matters my vac canister is in the right front pocket and has a long small tube for supplying a quick enough reaction to the servo's need. Seems like I have a lot of vac line drag for the chamber to to deliver it's potential. Don't worry, I already know where yours is
John, do you think it matters my vac canister is in the right front pocket and has a long small tube for supplying a quick enough reaction to the servo's need. Seems like I have a lot of vac line drag for the chamber to to deliver it's potential. Don't worry, I already know where yours is
OP
OP
moddy
the mod
Changed the location of the VAC container from the right fairing to underneath the swing arm. I removed 21 inches of vac tubing that should reduce the lag time for the servo needs due to resistance of the quarter inch vac tubing. It's the difference between drinking from a 15 inch straw compared to a 35 inch straw.
John OoSTerhuis
Life Is Good!
No, it was in fact the pull lever I installed on the throttle bellcrank that I was referring to:
Without having to remove the lever...
Zoom in on this: http://www.st-riders.net/coppermine/displayimage.php?pid=814&fullsize=1
A straight lever works just fine, it was just me being anal retentive. Even with my bend though it still didn't interfere with any part of the ST.
No, IMO. The canister in normal operation has constant vacuum applied to it and when vacuum from the intake manifold(s) drops off, the one-way check valve snaps shut to retain the vacuum for the servo to use. However, a long hose to the vacuum reservoir does have a small risk of crimping/pinching, leaking, and/or collapsing. I know of one STrider who used a sealed tin container of some kind (coffee or cookies..?) for his vacuum reservoir only to soon find it crushed by the vacuum generated.
John
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OP
OP
moddy
the mod
I saw the picture of that vac container, it still worked as I remember. It also seemed smaller than the volume of my vac container. I think my system vac isn't able to produce meaningful vacuum for use or storage.
Went out for a test ride, all changes in components, moved connections to bellhousing and a shorter run of vac tubing to a 1 1/2 by 8 inch vac container.
Things I'm sure of and don't need to triple check.
1. vac container does not leak.
2. All new tubing used in the placement of vac system, good, tight seals around ports for vacuum. (Doesn't mean I don't have a system leak somewhere, it sure acts like it.)
3. Orientation of the one way valve. I am "T'd" into the connector between cylinder #4 and the "T" connector between #2 and #4.
4. Does not hang up in the the actuation of the cruise links or manual throttle movement.
5. Soldered and shrink tubed pig tail connections at the coil ground, constant brake light power and signal brake power for disconnecting cruise with brakes.
6. Servo settings 1 and 7 are on, 2-6 are off.
Observations on the test ride.
1. Initiated cruise at 55mph on flat ground with a small hill coming. That doesn't describe much, so it was about 20ft high over 300ft long, a welcome first test.
As I began to slow, the servo pulled with the systems vacuum. Son of a gun at the apex of that hill it kicked off.
2. Initiated cruise on flat ground at 65mph, mild hill coming, half the size and distance of the previous hill, disengaged cruise immediately.
3. Pull over, disconnect and ground the purple wire in case the 125mv I was experiencing with a voltmeter is why it is disconnecting, now my brake will not disengage cruise.
4. Engage cruise at 55mph on flat ground, no hills, disengages in about 20 seconds.
5. Engage cruise at 65, flat ground, begins disengaging immediately.
My electrical connections are good. My vacuum system reads between 10.5 to 11.5 inches, what vacuum should I have, what do you get?
Engaging cruise while parked, in neutral, shows the vac system going to 5 inches with the initial set. It obviously disconnects immediately because the rpm's are all over the place but the test was designed to watch the vac system reaction to the efficiency of my engine producing vacuum and the container I made to hold the vacuum.
The servo pulls very hard, it aggressively sets and resumes, almost like it's driving down the vacuum so low it disconnects on purpose.
It seems as if there was a way for it react more slowly it wouldn't impact the total system vacuum, giving it a chance to catch up.
I am considering attaching all 4 cylinders for a vacuum source because I'm running out of ideas unless I put a watermelon size vac container in my left side case. I don't think making a vac container 2 inches by 8 inches will make much difference.
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OP
OP
moddy
the mod
In the meantime, while I'm waiting for responses. I will be checking what I can do with servo settings. I remember there being a setting for larger under powered engines. I'm not setting it because I think the engine is underpowered. I'm setting the servo for an engine that if it were underpowered and not producing as much vacuum won't pull so aggressively on the cable. I don't need it to go crazy, I just need it to stay consistent.
If that test ride doesn't prove successful and I haven't heard from anyone, I will add cylinder #1 and #3, because I'm running out of things I can do short of a larger vac container. Not a much larger one can be contsructed and I don't think that's my problem. So, servo setting first..
If that test ride doesn't prove successful and I haven't heard from anyone, I will add cylinder #1 and #3, because I'm running out of things I can do short of a larger vac container. Not a much larger one can be contsructed and I don't think that's my problem. So, servo setting first..
John OoSTerhuis
Life Is Good!
- resistance, binding, or friction somewhere in the ST's throttle control system (handlebar grip housing, cables' tension or return spring or sleeve, carbs' linkage). How much effort does it take to roll the throttle on? When released does it return smoothly/easily to the idle stop?
- vacuum leak. Unplug the hose from the check valve and apply vacuum to this hose (that leads, is connected, to the servo and reservoir) with a MityVac, or other tool with a gage. Wait and watch the gage. If it bleeds off you've got a vacuum leak. Until you do this you can't claim you don't have a leak.
- defective servo. There are a few cases that I know of where the servo vacuum solenoid started to bind, but only on old, hard used ones. My friend Jim Neagle documented his repair to return his servo to function (I'll look for it if asked). But I doubt that's your problem.
Something's missing...
John
- vacuum leak. Unplug the hose from the check valve and apply vacuum to this hose (that leads, is connected, to the servo and reservoir) with a MityVac, or other tool with a gage. Wait and watch the gage. If it bleeds off you've got a vacuum leak. Until you do this you can't claim you don't have a leak.
- defective servo. There are a few cases that I know of where the servo vacuum solenoid started to bind, but only on old, hard used ones. My friend Jim Neagle documented his repair to return his servo to function (I'll look for it if asked). But I doubt that's your problem.
Something's missing...
John
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John OoSTerhuis
Life Is Good!
Correction - Jim Neagle, STOC #8083, used the info and pictures of Paul Wilhelm, aka NikonHonda, STOC #8598, to repair his:
https://www.st-owners.com/forums/showthread.php?112500-Need-opinion-on-CC-wiring-re-do
Edit: at this time my guess is a vacuum leak.
John
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John OoSTerhuis
Life Is Good!
The 1.25" figure is the distance measured from the center of the bellcrank to the hole/attachment point for the AudioVox pull cable (the ball cage piece). The arm should be mounted on an angle as mentioned in the text/caption for the install picture (http://www.st-riders.net/coppermine/displayimage.php?album=33&pid=813#top_display_media) and shown in the next (http://www.st-riders.net/coppermine/displayimage.php?album=33&pid=814#top_display_media), NOT straight down. At about the 7:30 o'clock position.
Just to be clear. The CC has to have that range of movement to operate correctly, IMHO.
John
OP
OP
moddy
the mod
No resistance binding or friction in the throttle control, it's beautiful. No effort to roll the throttle on, it feels as though nothing is attached to the throttle. Full on to closed throttle is consistently smooth.
Switching the dip switch #5 to on had no difference that I could tell from it being switched off.
I cut the vac tubing to place another "T" connector to test the system with engine running at idle in the garage, 10 inches. When I took off again, because I'd placed another "T"connector, I preemptively placed another vac line from cylinder #1. I'm trying to rule out why the servo quits with no other kinks or throttle obstructions.
My last test ride, cruise set at 55mph but it didn't take, so I just pressed the button again, prepared for the strong lurch, and the speed set properly. On the first incline, it cut out half way up the hill.
Next try, 65mph hoping for a stronger vacuum and different experience, no avail.
Last time I set the cruise on the way home it cut out after 10 or 15 seconds on flat ground!!
I appreciate all the help, you guys really care or the exchange wouldn't have gotten to nearly 100 posts on the subject. I'm not done trying to get it to work yet, but after 8 days total of deliberations I have to put it to rest for now. I'm still looking forward to my ride to Louisiana then Texas then home to Indiana. The bike works, it's just not playing well with the Audiovox and I am so close. Til the next time..
OP
OP
moddy
the mod
The range is good. When my throttle is at zero, the servo cable is completely extended and there are 1 or 2 balls of slack as to not put any burden on the servo cable, keeping the throttle from returning to zero. It has been cutting out about mid throttle, well before any cable tension would develop in the servo.
I agree with you that it is a vacuum issue, just don't know why. Even with a leak in the system, you'd think 3 cylinders pulling vacuum on the manifold would maintain 60mph on flat ground.
John OoSTerhuis
Life Is Good!
Not to beat a dead horse here but... you've reduced the range by half. On mine, that first 30° of rotation are just getting the throttle to the middle of its range. On yours you may be just reaching it and can't rotate any further. Did you follow my install tip... where was the end of your lever with the throttle set wide open?
This may not even be your big problem but it's an important part of the mechanical install.
Have a look at the repair thread I posted. Maybe you should look at a sticking solenoid in the servo...
John
OP
OP
moddy
the mod
I did look at the repair post and like the idea of the attention the solenoids might need. I don't know how long the Audiovox sat in it's box before I came into it. I should have time after next Sunday to get into the servo.
I want to carefully describe the travel my throttle has compared to the servo cable, to insure we're solid on how it's set up.
My reference to the servo cable extended, is all the way out and able to retract fully, due to the vacuum operation of acceleration.
With the throttle at zero, the servo cable hardware is mounted so there is a little slack at full cable extension. This is obviously so the throttle is allowed to return to zero without being restricted by the full extension of the servo cable.
At full throttle, there are 1 or 2 beads of slack the servo is not able to take up. I don't know what can be done about this, favoring the slack with the throttle at zero.
I have also noticed, many times, the servo is disconnected at mid throttle range, 65mph on flat ground, not giving it a chance for much cable movement.
Last observation. When it does disconnect, I immediately hit resume, sometimes immediate disconnect, met with an immediate resume, then disconnect THEN, when I resume the 3rd time, a 4 to 5 times the length of acceleration to get back to the original speed set. Query. How could it do that if there is a vacuum leak and not a problem with a little servo R&R?
OP
OP
moddy
the mod
Just noticed this. My arm is at the same angle as your with 0 throttle. I probably meant that's the position it was making contact with the tank.