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Installing new Air Tubes on 1971 R75/5 (Questions)

jbf

New member
Hi all,

So I was reading around on various web forums and someone had mentioned something about mouting the left air tube upside down was common.

Can someone explain how I will know if I have installed the tube upside down? I installed them about a week ago and Im not sure if I did it correctly now.


Cheers,

Jonathan
 
Jonathan -

The air tubes that connect the air filter to the carb have different part numbers, so they are different left to right. You'll see when looking down from the seat that the cylinders are offset, so that means that one of the air tubes will be different shaped because of that.

I had to experiment with my /7 air tubes and noticed that they looked "wrong" when installed in one orientation. It seemed that they looked "wrong" when the section that was connected to the carb inlet was not parallel with the carb throat centerline...it had some slight angle associated with it. When I turned it around the other way, it made a straighter approach into the carb.

I suspect someone might remember if the slits on one of the tube needs to be at one end of the other...I don't.

That's all I can say...try it both ways and I think you'll see that one looks better than the other.
 
I'd say that if you got them on, and the bike is running that there's pretty good chance that they're in the correct position. The difference in length between the two makes it pretty obvious when it's not "right". Besides left to right, you can also have them "upside down" (just to keep you up at night wondering....)

But there's a clue that you've got them right, if they are the original tubes. Originally the air tubes were silver. After a time, exposure to the sunlight bleaches the plastic to a "natural" tan color on the top side. The underside usually remains silver.

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Can one even find original airtubes anymore? Wouldnt the plastic by now have started to harden/get brittle?


On a side note,

Anyone have tips for installing a new acid filled battery? Someone mentioned backing out the rear subframe bolts (under the seat) just enough to squeeze it in (after removing the hex bolts on the battery box to allow it to swivel).
 
Anyone have tips for installing a new acid filled battery? Someone mentioned backing out the rear subframe bolts (under the seat) just enough to squeeze it in (after removing the hex bolts on the battery box to allow it to swivel).

That's what I do with the "slosh" batteries on my /7...I prefer them. But there are sealed batteries that make it easier, such as WestCo, Odyssey, etc. You'll need to research to find the right model - cranking power, terminal location, dimensions, etc. Note that your bike was designed to work with a lead-acid sealed battery...you won't get the optimum charging for these newer batteries, but it will probably be good enough. Usually (being very general here), slosh batteries tend to give more of a warning that there is a battery problem; the other batteries tend to fall off a cliff and fail with no waring.
 
Yeah I already have the battery, I just need to get it installed. I realize that the honda dealership i ordered the battery from didnt give me the clear drainage tubing for the battery. Where can you find these?
 
most hardware stores like ACE have clear tubing in many sizes $ by the foot

some medical supplies also will work - check for tubing from oxygen using person
I seem to remember from my mother's gear 15 yr or more ago that some part of the
supply tubing or nasal canula was the right size
 
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