Mechanicl Secondaries...HELP
11-14-02, 01:44 PM
#1
Mechanicl Secondaries...HELP
Ok, Sterling (or anyone else)...Please help out with this. I REALLY want to do your mods to my car (mechanical secondaries and what not, but Im a visual person. I have read your post many times, but for the life of me, I can picture it in my head. If anyone could describe what things look like, or take pics, that would be great. Personally, I think thats the only thing that article is missing. I think someone (cough cough Manntis) should make a "How-To" with pictures for converting to mechanical secondaries...It would be AWESOME! I took some stuff off my carb last night jusst trying to understand, but its just not working for me 
. I did take my secondary spring out, and it seems to have made a small difference, but I want to do it your way. Anyway, if anyone could help, that would be great.
~T.J.
. I did take my secondary spring out, and it seems to have made a small difference, but I want to do it your way. Anyway, if anyone could help, that would be great.~T.J.
11-14-02, 02:37 PM
#3
standard combustion
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You need to disconnect the afterburn valve on the rear right of the carb to gain easy access. Its held on by 2 10mm bolts and has a couple vacuum hoses and one larger one too. Then you will see there are 2 main shafts controlling the butterflys. If you have a friend press the gas, you will see only the one shaft moves, thats your primarys.
Now, the other side is the secondaries(right side of car) controled by the vacuum. You will be wiring them together with mechanics wire so that the little hook that connects it to the primary to the secondary will pull it open when ever throttle is applied.
Sorry no pics, keep waiting, someone has the pics of this mod.
After done, don't forget to put the afterburn valve back on.
Now, the other side is the secondaries(right side of car) controled by the vacuum. You will be wiring them together with mechanics wire so that the little hook that connects it to the primary to the secondary will pull it open when ever throttle is applied.
Sorry no pics, keep waiting, someone has the pics of this mod.
After done, don't forget to put the afterburn valve back on.
11-14-02, 04:40 PM
#4
I read your email
Also, the vacuum actuator is located at the front of the carb passenger side. I temporarily removed some sorta sensor to get at it. Anyway, you do not have to remove the vacuum actuator right away. Just disconnect the actuator arm from the butterfly. There's a tiny cotter pin holding it on. You can take the actuator off later when you need a tinkering job to do.
WackyRotary's description is pretty good. Have someone press down on the gas pedal while you play with the linkage. When their foot is about 3/4 pressed down you'll see a linkage move that releases the secondary butterfly linkage. You want to wire it so that this linkage PULLS the secondary butterfly instead of just releasing it. All you need is a piece of wire slightly bigger then a garbage bag twist-tie wire. That should do it. I hope this helps. Good luck!
WackyRotary's description is pretty good. Have someone press down on the gas pedal while you play with the linkage. When their foot is about 3/4 pressed down you'll see a linkage move that releases the secondary butterfly linkage. You want to wire it so that this linkage PULLS the secondary butterfly instead of just releasing it. All you need is a piece of wire slightly bigger then a garbage bag twist-tie wire. That should do it. I hope this helps. Good luck!
11-14-02, 05:35 PM
#6
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I started to work on this at one point, but I got stuck. After I removed the vaccum box for the secondaries I had nothing to plug the hole with. Any suggestion for something that would hold up and/or be removable? I'd use JB Weld, but I'm afraid of having it sucked into somehwere it ain't supposed to be.
11-14-02, 05:42 PM
#7
standard combustion
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Well, you don't need to do ANYTHING to the vacuum anything. Forget about that. It can be there and won't cause any problems. Mechanical is stronger then vacuum, it will work fine, i've done this to several peoples Nikki's.
Just wire the throttle shaft to operate the secondary shaft, its redicously easy. Less then five minutes work! Just need some mechanics wire or something simaler, 10mm socket wrench to take off the round afterburn valve to gain access in rear of carb.
Just wire the throttle shaft to operate the secondary shaft, its redicously easy. Less then five minutes work! Just need some mechanics wire or something simaler, 10mm socket wrench to take off the round afterburn valve to gain access in rear of carb.
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11-14-02, 06:18 PM
#9
Nikki-Modder Rex-Rodder
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Man I wish I had a digi-cam! Then that write up would'nt be so damn wordy!
The quick way:
Keep in mind two things...This was a while ago that I did this stuff, and my carb is a Yaw carb with very little extranious crap on it. It does NOT have the decelleration dashpot on it, the AC idle compensator on it, any choke **** on it, yaddayaddayadda. Soooo, I may be overlooking the fact that YOU might have to work around some of these things.
Leave the vacuum box in place. Disconnect the tiny cotter pin that holds the arm in the middle of that box to the 2ndary throttle shaft. (You may have to wire it up out of the way.) If you have already removed the vaccum box, thenthe vacuum hole really should be plugged with something...anything, really. You just want to be able to remove it later if this is'nt cool for you. Don't use JB Weld! That's a permanant thing. You can do that later on when you've made the decision that you like this mod. The reason it should be plugged is because it is acting like a vacuum SIGNAL leak. IE, it's air entering into the carb, but not through the booster venturi. It should be only coming through the booster venturi as that's what draws fuel from the main circuit. It's probably just a little bit of suction missed, but we're trying to squeeze everything we can out! It was NOT a leak when the box was on, as air did'nt go through it...It only sucked the diaphragm closed.
So (Car off!)- Now when you open the primaries by holding the linkage with your hand, you can use your other hand to find out that your secondary shaft can flop back and forth! hold that one open, and let the primary back down real slow. Soon it will "catch", and you'll feel the secondaries wanting to close.
This is because the primary shaft is in control of a spring that keeps the secondary held down shut. So even when you had alot of vacuum signal through the carb, those secondaries were'nt gonna open till the primaries were opened that far at least!
So now just move the primary shaft-slowly. You should be standing on the Passenger side of the car, BTW. (Unless you're 7 feet tall, I don't see how you could stretch the other way!) This time, watch the linkage and pay careful attention to what little parts are making contact between the primary and secondary shafts. These are the washers with the lobes that stick out that I describe in the text. As the primary opens further, a lobe on one of those washers eventually makes contact with one of the washers on the secondary shaft, But nothing seems to happen. But what's happening is that the secondary shaft washer that's spinning free on that shaft is really attached to a spring. The spring is kind of hidden, wrapped around the throttlebody part where the secondary shaft sticks out. It is taking the tension of that spring off the secondary shaft.
You need to observe, and fully understand just what is actually making all that hodge-podge work. Then it becomes SUPER EASY and clear that all you have to do is wire those two parts together so that the secondary moves when that washer moves.
But you just won't see **** if your carb is dirty and fulla black ****. Ya gotta clean it. And ya gotta get right down in there to see it all, too.
But I'll tell you this-
Once the lightbulb goes off in yer head and you see how easy it is, GO BACK AND RE-READ THAT WRITE-UP!!! There are pitfalls that you NEED to know about to ensure the best performance possible.
I'll keep checking back here, and you can all ALWAYS feel free to E-mail me.
I will do my best to get some pictures out.
The other mod is really for people who feel very comfortable with the idea of taking apart their carb. Having at least one re-build job under your belt will really help with that. Not that it can't be done by someone new to the Nikki carb; Just that when you're unfamiliar with the carb, it seems like more of a job than it really is.
Good luck, and keep in touch. I'm really excited to see more people playing with their carbs!
The quick way:
Keep in mind two things...This was a while ago that I did this stuff, and my carb is a Yaw carb with very little extranious crap on it. It does NOT have the decelleration dashpot on it, the AC idle compensator on it, any choke **** on it, yaddayaddayadda. Soooo, I may be overlooking the fact that YOU might have to work around some of these things.
Leave the vacuum box in place. Disconnect the tiny cotter pin that holds the arm in the middle of that box to the 2ndary throttle shaft. (You may have to wire it up out of the way.) If you have already removed the vaccum box, thenthe vacuum hole really should be plugged with something...anything, really. You just want to be able to remove it later if this is'nt cool for you. Don't use JB Weld! That's a permanant thing. You can do that later on when you've made the decision that you like this mod. The reason it should be plugged is because it is acting like a vacuum SIGNAL leak. IE, it's air entering into the carb, but not through the booster venturi. It should be only coming through the booster venturi as that's what draws fuel from the main circuit. It's probably just a little bit of suction missed, but we're trying to squeeze everything we can out! It was NOT a leak when the box was on, as air did'nt go through it...It only sucked the diaphragm closed.
So (Car off!)- Now when you open the primaries by holding the linkage with your hand, you can use your other hand to find out that your secondary shaft can flop back and forth! hold that one open, and let the primary back down real slow. Soon it will "catch", and you'll feel the secondaries wanting to close.
This is because the primary shaft is in control of a spring that keeps the secondary held down shut. So even when you had alot of vacuum signal through the carb, those secondaries were'nt gonna open till the primaries were opened that far at least!
So now just move the primary shaft-slowly. You should be standing on the Passenger side of the car, BTW. (Unless you're 7 feet tall, I don't see how you could stretch the other way!) This time, watch the linkage and pay careful attention to what little parts are making contact between the primary and secondary shafts. These are the washers with the lobes that stick out that I describe in the text. As the primary opens further, a lobe on one of those washers eventually makes contact with one of the washers on the secondary shaft, But nothing seems to happen. But what's happening is that the secondary shaft washer that's spinning free on that shaft is really attached to a spring. The spring is kind of hidden, wrapped around the throttlebody part where the secondary shaft sticks out. It is taking the tension of that spring off the secondary shaft.
You need to observe, and fully understand just what is actually making all that hodge-podge work. Then it becomes SUPER EASY and clear that all you have to do is wire those two parts together so that the secondary moves when that washer moves.
But you just won't see **** if your carb is dirty and fulla black ****. Ya gotta clean it. And ya gotta get right down in there to see it all, too.
But I'll tell you this-
Once the lightbulb goes off in yer head and you see how easy it is, GO BACK AND RE-READ THAT WRITE-UP!!! There are pitfalls that you NEED to know about to ensure the best performance possible.
I'll keep checking back here, and you can all ALWAYS feel free to E-mail me.
I will do my best to get some pictures out.
The other mod is really for people who feel very comfortable with the idea of taking apart their carb. Having at least one re-build job under your belt will really help with that. Not that it can't be done by someone new to the Nikki carb; Just that when you're unfamiliar with the carb, it seems like more of a job than it really is.
Good luck, and keep in touch. I'm really excited to see more people playing with their carbs!
11-14-02, 06:24 PM
#10
Airflow is my life
It does NOT have the decelleration dashpot on it
?????? I thought that we discussed that and it was a bad thing to do even though Yaw does it???? What did I miss? Your gonna make me do it to the daily driver now to test it! GRRRRR....
?????? I thought that we discussed that and it was a bad thing to do even though Yaw does it???? What did I miss? Your gonna make me do it to the daily driver now to test it! GRRRRR....
11-14-02, 06:27 PM
#11
Nikki-Modder Rex-Rodder
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It does'nt have it cause I've been to lazy...err, uh, BUSY to put it on there!
But hey, try it, Carl. I could be wrong. I put an SE diffy in and it always did whine like hell, so maybe the ring and pinion just have too much slack.
But hey, try it, Carl. I could be wrong. I put an SE diffy in and it always did whine like hell, so maybe the ring and pinion just have too much slack.
11-14-02, 10:47 PM
#14
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Originally posted by Sterling
CONVERTING TO...MECHANISISM?!?
You need to disconnect the throttle cable and choke cable before anything.
Now, yank off that vacuum box, along with the linkage. Well....don't "yank" it off, but remove it as if you were doing surgery on your dog. (You love your dog, don't you?) Don't destroy, or change anything that can't be put back the way it was. There are 3 holes on the carb where you took the box off; two for screws, and one where a short black plastic tube from the box went into. That hole is the vacuum hole, and should be plugged with perhaps a piece of rubber or plastic that you can remove later if you want to put everything back the way it was.
CONVERTING TO...MECHANISISM?!?
You need to disconnect the throttle cable and choke cable before anything.
Now, yank off that vacuum box, along with the linkage. Well....don't "yank" it off, but remove it as if you were doing surgery on your dog. (You love your dog, don't you?) Don't destroy, or change anything that can't be put back the way it was. There are 3 holes on the carb where you took the box off; two for screws, and one where a short black plastic tube from the box went into. That hole is the vacuum hole, and should be plugged with perhaps a piece of rubber or plastic that you can remove later if you want to put everything back the way it was.
11-14-02, 11:36 PM
#15
Right now rotormotordriver and I are going back and forth on IM, he's taking pics (i have no digi cam) and I'm doing a writup which I will put up on my website. Hopefully I'll be able to put it up tonight, but we'll see. I'll be sure to let everyone know when its done, it should clear up a lot of the confusion. I hope....
11-15-02, 12:19 AM
#16
Well, I've got something. Its not much, but it might just be enough. check it out: www.slegers.com/sites/sean then go to "tech writeups" then the mechanical secondaries one. Here it is 1:15am, I've been at this computer for 4 hours so I'm sure theres a lot of room for improvement in the writeup. Check it out and leave some feedback here. thanks.
11-15-02, 04:40 AM
#18
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Step 1. Remove the blue air box. This will reveal the carb. (This amused me, I don't know why )
It might be time to clean that carb... that's some mighty fine build-up. Good little write, should be helpful to others.
)It might be time to clean that carb... that's some mighty fine build-up. Good little write, should be helpful to others.
11-15-02, 10:50 AM
#20
Thanks for the compliments guys. haha, yea I guess that step 1 does sound kinda goofy.
maguire: you want me to just make a post out of my page? is that what you mean by mirroring it? If it is then its cool with me, I can do it later, I just came on here to check this really quick.
maguire: you want me to just make a post out of my page? is that what you mean by mirroring it? If it is then its cool with me, I can do it later, I just came on here to check this really quick.
11-15-02, 12:16 PM
#22
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I don't understand why it is necessary to mess with the vacuum linkage arm at all. Once you wire the secondaries up to the primary shaft, the movement of the secondary shaft is strictly controlled by the throttle pedal movement. The vacuum actuator will only mirror the movement induced mechanically, with some delay of course. So why bother?
11-15-02, 12:18 PM
#23
I read your email
Originally posted by Strider
I don't understand why it is necessary to mess with the vacuum linkage arm at all. Once you wire the secondaries up to the primary shaft, the movement of the secondary shaft is strictly controlled by the throttle pedal movement. The vacuum actuator will only mirror the movement induced mechanically, with some delay of course. So why bother?
I don't understand why it is necessary to mess with the vacuum linkage arm at all. Once you wire the secondaries up to the primary shaft, the movement of the secondary shaft is strictly controlled by the throttle pedal movement. The vacuum actuator will only mirror the movement induced mechanically, with some delay of course. So why bother?
11-15-02, 12:56 PM
#24
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Originally posted by inittab
Good point!
Good point!
Personally I don't think that is such a big issue though, and the stress relief on the mechanical linkage due to the vacuum linkage might be better for longevity of the linkage and throttle shaft seals.