Airbox

JoeInTUS
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Re: Airbox

Post by JoeInTUS »

It mounts under the igniters. Held by a rubber strap that is usually broken at this point.
IMG_0274.jpeg
Somebody on the forum had replacement straps for sale. Tevan maybe?
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tevan
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Re: Airbox

Post by tevan »

You are correct Joe I have new straps that work great! $15 plus shipping

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oroepke
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Re: Airbox

Post by oroepke »

Oh that’s where it goes! Weird, I mounted my new reg/rec right in that spot in the center. I need to take another look. For now I put a plug over the airbox drain.
Tevan, I may be in Touch about the strap after I figure things out.

On another note, I got everything set up for syncing, interestingly, contrary to what others said, I can reasonable well access adjuster screw 5-6 with my long tool, however 3-4 is difficult to get to because the coils are in the way. Any ideas?
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JoeInTUS
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Re: Airbox

Post by JoeInTUS »

It looks like you have a Dyna ignition. If you do, then you no longer have the igniters and a place to mount the “spooge” tank. In that case I usually use a few inches of 1/2” Tygon tubing with a PEX plug at the end.

https://www.homedepot.com/p/Apollo-1-2 ... /301541173
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oroepke
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Re: Airbox

Post by oroepke »

JoeInTUS wrote:
Sun Aug 06, 2023 6:27 pm
It looks like you have a Dyna ignition. If you do, then you no longer have the igniters and a place to mount the “spooge” tank. In that case I usually use a few inches of 1/2” Tygon tubing with a PEX plug at the end.

https://www.homedepot.com/p/Apollo-1-2 ... /301541173
Sounds good! I'll go that route, thanks!
New 1980 CBX owner as of January 2023!
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Re: Airbox

Post by 512tr »

On another note, I got everything set up for syncing, interestingly, contrary to what others said, I can reasonable well access adjuster screw 5-6 with my long tool, however 3-4 is difficult to get to because the coils are in the way. Any ideas?
If that is your only problem, temporary loosen the coils and extend the wires if needed, and reinstall after sync is done.

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oroepke
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Re: Airbox

Post by oroepke »

512tr wrote:
Mon Aug 07, 2023 10:01 am
On another note, I got everything set up for syncing, interestingly, contrary to what others said, I can reasonable well access adjuster screw 5-6 with my long tool, however 3-4 is difficult to get to because the coils are in the way. Any ideas?
If that is your only problem, temporary loosen the coils and extend the wires if needed, and reinstall after sync is done.
I agree sounds like the best option. Thanks.
New 1980 CBX owner as of January 2023!
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oroepke
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Re: Airbox

Post by oroepke »

I started syncing the carbs, however I must say I don't really trust the cheap vacuum gauges that I have (the set of four you see everywhere). I am not 100% sure if they are reading the same vacuum. Even after adjusting them with the little screw I am not convinced.

Has anyone gone the route to use just one gauge and a "gang-valve"? That would eliminate any possible error in readings from one gauge to another, and seems reasonably convenient to switch over between carbs. Any thoughts? Anyways, for 10 bucks on Amazon you can't get wrong so I am going to give this a try as well. I have the feeling this will not be my only sync session, so I want to make it as convenient as possible!
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Re: Airbox

Post by daves79x »

The 3-4 sync adjuster has the tool pretty tight against the coil frame, but you should never have to loosen the coil pack to get to it. Get six gauges and the process will be much easier. You are asking for real trouble trying to use just one gauge. You don't want the engine idling any longer than absolutely necessary to do this.

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Re: Airbox

Post by 512tr »

I did a simple box to sync the gauges.
Those cheap gauges could be adjusted to O without vacuum, but could be out of sync when you apply vacuum. I sync the gauges by vacuum from my car to avoid overheating the CBX.
Skjermbilde 2023-08-08 153824.png
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oroepke
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Re: Airbox

Post by oroepke »

daves79x wrote:
Tue Aug 08, 2023 8:12 am
The 3-4 sync adjuster has the tool pretty tight against the coil frame, but you should never have to loosen the coil pack to get to it. Get six gauges and the process will be much easier. You are asking for real trouble trying to use just one gauge. You don't want the engine idling any longer than absolutely necessary to do this.

Dave
Dave you are right, It was a tight squeeze but I was able to get around the frame and reach to 3-4. Started syncing 4-5-6 with 3 gauges yesterday. At 100F in the garage I stopped after a couplke minutes, the engine seemed to be very hot already, I will do this in stages spread over multiple days. I have six gauges available, so we'll see how it goes. Maybe when I am done, I just switch gauges around to see if I am still synced.
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oroepke
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Re: Airbox

Post by oroepke »

512tr wrote:
Tue Aug 08, 2023 10:37 am
I did a simple box to sync the gauges.
Those cheap gauges could be adjusted to O without vacuum, but could be out of sync when you apply vacuum. I sync the gauges by vacuum from my car to avoid overheating the CBX.Skjermbilde 2023-08-08 153824.png
Good idea. In place of the nbox I could use the splitter.
New 1980 CBX owner as of January 2023!
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Previous bikes: Several SOHC Hondas and KZ's, a few BMWs, Honda CT, HD Fatboy, XL 500, DR 750, RD 350, CB250....

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oroepke
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Re: Airbox

Post by oroepke »

So I finished syncing and all went really well. I ended up using all 6 gauges, it turned out they weren't too far off from each other. Coming off idle is really crisp now, but I still have the stumble between 1500-3500. My "fear" is that it's the slow jet and I have to go back in there, even though I cleaned everything really well, even extracting the slow jets. But then the carbs sat on the work bench for a three months....

Anyways, for now, I will put some miles on the bike, maybe I am lucky and carbs free themselves up! Just need to keep it above 3500!
New 1980 CBX owner as of January 2023!
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oroepke
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Re: Airbox

Post by oroepke »

Happy Saturday everyone! I would appreciate any suggestions on what I should tackle next, to get rid of the stumble, here a summary of what I have done in the last days:

Rode the bike for 20 mls or so, ran great above 4,000 and below 1,500, I think the carb sync at least was a success. I had the feeling that the bike was running lean betweeen 1500-4000. I took out all plugs after riding a few miles with less than 1/4 throttle and in fact they looked a bit to whitish to me, however not totally off. To test for vaccum leaks I sprayed starting fluid around the outside of the carbs and manifolds with the engine running, no change in idle, so I don't think there are any vacuum leaks. I then took out the paper air filter and covered 50% of it with tape. With that, the bike runs much better now, I have a stumble only between 2000-3500.

Does that mean I should try a larger pilot jet? I am reading some folks drill theirs to #36.5. Or should I use #38? Carbs are all stock now (pilot #35, Main #110, Needle 55A), I still have the 6-in-1 with Super Trap muffler on there, currently running six discs in the muffler, which I believe is comparable to stock. And I forgot to mention, looks like I also have polished intakes.

I'd hate to take the carbs off again, but I am aware, that the average wrench has to take them off about 3 times to get it right! If that's true, I have 2 more to go, lol! Thanks anyone for any ideas you may have!
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Re: Airbox

Post by hondaman160mph »

If you have to cover half of the air cleaner to get it to run better your carbs/jets aren't clean.
I have an 82 with stock jets, a Kerker 6 into 1 with a Supertrapp canister with a straight through silencer.
It runs perfect from idle to redline with no flat spots or hesitation.

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