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advice for airbox installation

leo750k

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Well I finally got my air-box boots, any advice on installation is appreciated. My main question is do I attach them to the carbs first and then to the air-box, or vice-versa?
Thanks for the help
Leonard
 
I prefer to mount them to airbox first. The OEM install has them glued to airbox, they use like a contact cement there. It keeps them better in place when installing.
 
I have a couple questions: the tee between carburetor 2, and 3 that provides vacuum to the alum tube gallery, where does it draw vacuum from? there is a port on the #2
carburetor (between carburetor, and head) is that it?
If I remove the battery box to have more room to install the air-box, will I be able to reinstall the battery box with the carbs, and air-box installed?
Thanks for the help,
Leonard
 
Can't say battery box removal will help. It would likely be able to reinstall with box in place, but can't swear to that either. Most of airbox issue is with the striking and interfering with back frame backbone IIRC. Some have custom ground part of the AIRBOX backbone down a bit for more room.

The airbox always gives maximum fits going back in. I used pods and was able to always make them work fine but many do not keep engines in the kind of shape it takes to run them and why so many have major pod issues. The airbox DOES provide a slight low end torque hit the pods cannot, careful jetting can recoup some of that BUT again, the engine has to be perfect. I for one used an old school Kerker small tube diameter header that by design of the muffler section had the ability to make up for the lost hit, most headers cannot do that. The difference is in a LONG extremely SMALL holed baffle with ZERO packing that lets the engine feel the megaphone on end of pipe; that makes it act like the header is open when it is not. Most designs do not do that and if no meg on the end absolutely cannot go there. The Kerker result is a big hit of torque that a regular Kerker fiberglass stuffed header will not produce in strictly OEM form at all. Simply putting the packing back in kills it utterly.

I lucked out discovering that particular setup and it repeated on 3 different engines to run great, why I kept that header above others. The very small tubes and peculiar muffler design just work and work. It does not sound overly loud either and the noise is very controllable by simply screwing the throttle back.

Back to business..................the #2 carb vacuum port goes to the vacuum demand valve bolted on back of carbs, plug it if not using that valve. The 2-3 tee is a bowl VENT, leave it open to the AIR.
 
Ok thanks for the vent and vacuum port info. I actually did not have to bad a time installing the air-box, boots on box, make sure all tubes and wires were out of the way, then I held the air-box as far to the rear as possible, and tightened down the mounting bolt good and hard so it would not slide forward. Then just took my time, and kept my eyes om all 4 of the air-box boots as I worked the carb rack into place. It really went pretty smooth. I was certainly glad that I took the time to seek advice on installing the air-box, it saved me lots of frustration.
Speaking of frustration, now that its back together, I have no power to anything at all, (you gota keep laughing) my manual (16-2)) pretty much says if its not the battery or it's connections then its the ignition switch or the "main fuse". Page 18-1 shows a 30A fuse in the starting circuit, but that is not a "main fuse", although I would like to know where it is. In my wire harness, about 6 inches forward of the battery, on the left side is a large object completely tapped up, inside the harness. I have thought it was some type of resister, might this be a "main fuse" ?
thanks for your help
Leonard
 
The 30 amp IS the main battery power fuse, trace it down in the system to find it to be so. Replace it with a common blade type fuse, the OEM fuse is a piece of crap and deteriorates over time. It is NOT a starter fuse.

Your other article is a diode, test it both ways and one way flows power, the other doesn't. Needed to stop arguing between the clutch and neutral switches at starter button control, no diode lets power run backwards in a circuit to mess things up.

You have the main fuse and then the 4 that split up power further in the handlebar fuse box.

If the ignition switch is not original or is an Emgo brand then the bottoms of them come loose sometimes to make a no power error. The bottom plastic used there was too flexible and then the contacts can come out to mess the switch up.
 
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