The Honda Aero 125 Thread

Hi, everyone.

I am starting this thread because I just purchased a 1984 Honda Aero NH125 scooter, and there didn't seem to be any other place catering to these rare, old 2-stroke bikes. As you may or may not know, Honda only imported them into the North American market for one year, and then dropped them in favor of the Elite.

The first time I ever saw one was when my daughter brought a gold one home last summer; she let me take it for a spin around the block and I fell in love with it immediately. It fit my 5' 4" height perfectly and it has that low center of gravity that made it feel really stable while being zippy and fun to ride.

I was determined to get one for myself, but only then realized how relatively rare they are. But after a short time, my bf was able to locate a red one (they only came in two colors that year: red and gold) on CL located not too far from our house — so the next day we went in our Montero to go pick it up.



How do you like it so far?

Here's the dash. Love that retro 80's vibe!!!!



Here she is all wrapped up in the Montero, headed to the beloved DMV for VIN verification. The scooter was licensed with Washington plates and had a problematic pink slip (but that's another story) and so the People's Republic of California had to make certain that nothing was amiss. What we do for love!



In the following weeks I'll be updating this thread as I iron out some of the mechanical problems that naturally come with adopting a 30 year old bike. These include mounting new tires, fixing a rough idle on the carb, and de-uglifying the torn seat. I'd love any input from you fellow inmates, particularly owners of Aeros or similar bikes of the same era. I'll be in the garage.

Motor Scooter Guide forum . . downloads.

Nice scooter. In my opinion, 12k miles is pretty high for a 2 stroke engine. You might think of doing major service to it soon. Including a new belt, all filters and a new top end on your engine. Check the brakes and tires too.

I see you have a trailer hitch already. If you bought a cheap scooter carrier for under $100 you wouldn't have to mess around transporting your baby like that. :eek1 Check craigslist in your area. There's always a few on there.

I just picked up an aero 80. I'd love to find a 125!

Sweet!

Good luck with it!

Welcome too!

tortoise ~

Thanks for the info on the scooter site; I'll check it out. My comment referred to the ADVrider site as far as finding an existing thread, but any info is greatly appreciated.

herman ~

I gotta say I love those new New York license plates. Just saw one out here in California recently and thought it looked like ours did back in the 1930s. Cool.

Your bike looks nice, too. A trailer would be a great idea instead of doing it Jed Clampett-style like a hick, but being Scottish I was able to save the $14.95 for renting one from U-Haul.

Does your scooter have a kick-start, and is the separate oil tank installed? Some PO decided to do a lobotomy on my scoot and removed the oil tank, forcing me to mix the oil and gas in a can and pouring this mixture into the gas tank directly. The oil nib on the carb has been closed off (That dull yellow thing just left of the intake mounting bracket) and I'm wondering if larger jets should be installed to accommodate this non-factory "upgrade?"



How many miles on your beast?

I bought an 85 Aero 80 last fall for $400. It had less than 1000 kms on it. It needed a new battery and a new front tire.

Look at the dry rot: (before)



New tire (after) … cost about $35



I loved my Aero - it was comfy, zippy, had a great putt-putt sound, was cheap to insure. Parts were easily sourced at my local Honda dealer and reasonably priced. Over the winter my buddy and I pulled the carb and gave it a good ultrasonic cleaning. It ran really well. Started getting noisy though. A little investigating and I discovered the nuts holding the exhaust to the engine were rattled loose. Replaced and tightened and the noise disappeared.

Bottomline: great scoot. I liked it as much, if not more, than the 85 250 Elite I had. I ended up selling the Aero due to having too many bikes. I sold it for $800 so I managed a profit but if I had my time back I would have made space and kept it. I really regret selling it. Yours is a nice, clean looking unit. Too bad the oil reservoir was removed. What a PITA having to do the mixing. I suppose you can do up a big container and just draw from it when needed. I'd be pissed about that. Ah well.

Keep us posted. I love old Honda scoots.

redarrow my 80 has only 140 miles. It wasn't ridden much! LOL.
It does have a kick starter & it still has the oil tank so mixing gas and oil isn't necessary. I'm sure you can find the parts you need to bring it back to stock condition. People get scared that the oil pump might stop working and the oil starved engine will sieze. I've heard of many overly paranoid people doing this and always shake my head wondering why they'd make life more difficult and their scootering LESS fun by mixing the gas and oil.

KLX250 ~ Thanks for writing. Sounds like you had a great bike. I wish I could walk into my local Honda dealer and find walls of parts. I guess that's what I get for falling for a one-year import. I don't know what's exchangeable between the Aero 80 and the 125, or the Aero, the Elite and the Spacy, for that matter.

Yeah, they're cheap. Mine was $550 and my daughter got her's for $600. It still amazes me that such a cool scoot is so affordable. Did yours run poorly at idle before you cleaned the carb because that's where I'm at now.

Maybe you can pick up another one some day...

Herman ~

Wow, 140 miles! How did that happen? It must have sat for quite a while. How does it run? It sure looks nice. These are really fun bikes when they are tuned properly. Keep me posted on what you do to it.


Carb update.

First of all, I spent the day removing and cleaning my carb, which is a Keihin PB02B with a 18mm venturi. Naturally, it took five times the time I thought it would because I wasn't sure how much pressure it took to yank the carb out of the airbox, dealing with 30 year old rubber and plastic parts. The PO had complained about stalling out during deceleration and even gave me a work invoice from a repair shop that replaced an o-ring at the intake housing but failed to list anything else that actually solved the problem.

The Aero ran great at full throttle, but wouldn't really hold an idle past a minute before committing hari-kari, scooter style. I played with both the mixture and idle screws but still no joy, so it was time to dive in and do the inevitable carb cleaning boogie. When removing the carb I also found the air cleaner dirty, so now I've got to deal with that as well as the carb.

Everything went fine taking the carb apart and I was happy to discover that the main jet was the proper size (#105) for standard elevation. For those of you who live in the mountains, you need a #100. A sticker warning about this is under my dashboard next to another one asking us all to respect nature and always wear a helmet. Right on, Honda!

But as I removed the fuel bowl I saw that the o-ring looked like it had seen better days, and even though it hadn't been leaking, I didn't want to risk it, so it was off to the local parts store to try and find a replacement while my jets soaked in a toxic stew.

I'll post some pictures tomorrow and can't wait to see if a clean carb & air filter solves my idling problems.

~ Tootles


New day. Haven't put the carb back on yet, but got it all cleaned up. I have to go up to the city today to earn some bucks so I can afford to reupholster my seat. So I'll leave you with a reminder that everyone thinks their ride is the best one. This is my daughter on her 1984 Aero 125. She almost bit my head off when I told her that I bought the same bike LOL. Kids...

I'd love to pick up another Aero some day.

The one I had idled fine before the carb was cleaned. It was leaking if I recall correctly.

I'm not sure about the interchangeability between the 80 and 125.

Here are a couple pics of my disassembled carb (if it helps):

Thee Aero 125 is a wonderful old scooter. I just love 2 strokes. Well designed, but as you said, very rare. And there lies it's biggest problem. Lack of parts. Here is a good place to get what new parts are still available.

http://www.cheapcycleparts.com/oemparts/#/l/hon/5053e04ef870021c54be04a0/1984-nh125-a-parts

Wow. Great responses, everyone. I'm still trying to figure out how to answer everyone that makes sense LOL.

JerryH ~ Thanks for the link. Maybe they can source me some needed things. I love 2strokes too

JerseyBiker ~ Your welcome is welcomed. Hope you lurk back.

Klx250 ~ Great photos. Beautiful burgundy scoot! Now I don't feel so bad trying to save a few bucks by not renting a trailer. Maybe we should start a thread on Jed Clampett Bike Moving Photos — we have a great start already. (I wouldn't want to try this with a Harley, tho.)

My tires aren't quite as bad as yours were, but the back one does need replacing so I went ahead and ordered two new Michelin Reinforced S83s and some tire spoons so when they arrive I'll have that little task to look forward to. Should be fun.

When I took my carb off, I realized that the air cleaner foam was hanging on by a thread and I'm afraid that if I try to remove it to clean it, it'll tear apart completely and the stupid thing is no longer in the Honda system. I'm considering getting some foam and making my own using hot glue. Any one know if this works or not?

So here's my carb with the bowl removed, showing the main jet, slow jet and the float. I was concerned that the main jet was the smaller high altitude one which would make everything run to lean. Super bad juju for a 2 stroke.:eek1



Jets soaking in old cat bowl. The bowl's old, not the cat. Good news is that some of those tiny holes were completely clogged and YIPPY the main jet (the little guy in the middle) was the right size (#105) for where I live, where I can gaze at the Pacific from my front porch.



But the scooter gods giveth and they taketh away. I found the o-ring that seals the lower bowl was pretty gnarley. Here's the offending part, along with its replacement — more Frankensteining ahead to make my scoot road-worthy.



Bring on the Krazy Glue...



Let's hope it works, LOL.



Presto! Here's the carb back together, clean and better than new (knock on wood) and ready to be reinstalled.



As you can see, the limiter at some point in time had been removed from the mixture screw on the left (Idle speed is the one on the right). Before disassembly, I'd seated both and then turned them out 1 & half turns to get a starting point for setting them once I get the darned thing fired up, which will happen once I get the air filter element situation rectified. One thing seems to lead to another on these things — unless you happen to be lucky enough to find one with only 140 miles on it.

I still can't believe that in this age of ebay and Antiques Road Show that stories like that are even possible. That should give us all hope.

~ Tootles

Thanks everyone for posting. My full reply along with my carb rebuild photos are awaiting clearance by higher authorities.

Meanwhile, keep those great posts coming.

Sounds like you've got some fun ahead of you! The Honda scooters from the 80's are my favorite, and they can keep you moving for years with some maintenance. You can check with Jack Stanley at jack@jacksscootershop.com for parts and you certainly can get some info at his website. He's close by, somewhere in the San Jose area.

Also, there is info to be had, and a fair amount of young male posturing, at www.hondaspree.net which is really a website for any 2 cycle Honda machines.

Welcome to the world of old Honda scooters. You'll wonder why there aren't thousands of them running around.

Wentwest ~

Agreed. These old Honda scooters are the greatest!!!

Thanks for sharing those links. Super helpful, especially considering the lack of scooter shops here in Santa Cruz. You would think, being a college town, that there would be one on every corner, but no. According to the old timers, there used to be some, but they've all folded for one reason or another. We're lousy with surf shops and bike shops, but only so far we've found this one guy named Wayne who runs Cycle Revolution (I'm not affiliated ) who kindly let us go through a box of O-rings in order to find a replacement for my carb bowl along with the tip about the Krazy Glue. He didn't charge us for it, either.

It's such a cool thing how this hobby brings you in touch with so many great people who are willing to help each other, profit aside. Everyone take a bow.

I got the air filter sorted out, which was in better condition than I had first thought. I'll post pics soon, and hopefully I can get her back together and running today to see if cleaning the carb actually accomplished anything. Keep your fingers crossed.

Just buy some filter foam and cut a new one

Thanks, Forde. My foam was about a quarter inch thick and finding replacement foam would have been no problem; what I was mostly concerned with was what kind of adhesive to use that would join it together, as not every kind of glue likes mixing with gas & oil fumes. I did use Krazy Glue on the carb o-ring and it seems to not be leaking but I don't know how it would work on the foam.

Turns out that my foam element was sown together with something like a fine fishing line, which kind of surprised me. I used a K&N filter cleaning kit; I know there are probably cheaper ways to accomplish the same thing, but since this was my first time doing it, I thought I'd go with a tried and true brand.

Here's the filter removed from the holder, ready for cleaning.



As you can see, it's not in too bad of a shape, although it's a lot dirtier than it looks.



The first step is to spray the cleaner into the foam, working it in with your fingers.



Let it sit for about 10 minutes, but not so long that it dries out. Next, I got a bucket of cold water, and dunked the foam in it, gently squeezing. The gunk turned the water a foamy black immediately. I was surprised that the engine could run at all with all that dirt in there. It made me realize the importance of making sure the air cleaner is clean whenever you go to the trouble of cleaning your carb.



I did a second bucketful but as you can see the filter was pretty well clean after the first rinse.



Let it dry completely. You don't want water in there when you apply the filter oil. I'd say I let it sit out in the sun for about three hours (hoping that a seagull wouldn't take off with it) . Next, I sprayed it down with the K&N filter oil, making sure to cover it completely, both inside and out. The red color of the oil makes it easy to see if every bit of the foam is covered.



There she is, all cleaned up and ready for reassembly. Looks good enough to eat! Chocolate cake!



Installation of the carb and firing up next to come!

I'll be in the garage.

Nice job!!

First thing I did was pull the old spark plug and replace it with a new one, an NGK BPR6HS, for a standard heat range. The old plug looked a bit oily.



The plug should be gaped between 0.06mm and 0.07mm. Putting the carb back on the bike was quite easy; a few tight spots, mostly on the nut closest to the engine cover. Here's the carb being mounted to the air intake. There's not really room for fingers back there so you've got to use something like needle nose pliers to hold the nut in place until the bolt seats itself. Also, the auto bystarter (basically, an electric choke) is held on by a large nut which I found easier to connect to the carb before mounting the carb back on the air intake due to similar access issues.



How do you like my expensive carb throat protector? That white thing covering the carb was the cap to a water bottle, but it fit good and kept random things from falling inside.

With the carb back where it should be, it's simply a matter of reattaching the cleaned air filter to its housing in the air box. A label on the back of the air filter holder says UP. Put it on that way.



Last thing was screwing in the throttle cable into the top of the carb, replacing the fuel line and adding a new fuel filter. The fuel line might have been a tad too small, because it took a heck of a lot of effort to get it seated on the filter. Maybe the filter was too big.:eek1 I used some zip ties to make sure everything was snug.



So..... I wheeled her out of the garage and fired her up. Always a great moment, right? Wow, what a difference a clean carb and air filter make! Here I am in my mechanic's moment of triumph! Who says I'm all thumbs?



Where before she couldn't even hold an idle, now it's steady & strong. I had to fiddle with the mixture screw a bit, but not too much. Sadly, my funky rear tire prevented me from taking a victory lap, so it was back into the garage to change out my tires, which, as luck would have it, arrived that same day.

Here they are, fresh from the UPS truck, along with two Motion Pro spoons. (You really should have three.)







Because the way the stand is situated on my scooter, I decided to change one tire at a time to avoid a teeter-totter situation and give me more leverage for removing the big 22mm rear axle bolt. First things first. Remove the three bolts and two nuts that hold on the muffler. Turns out you don't have to remove the two nuts that hold the exhaust pipe to the cylinder completely because the flange is slotted and the whole thing just slides out sideways. The things you learn as you go!



Next, remove the lower shock bolt, the fender bracket and the swing arm.







Here's the 22mm rear bolt. It's torqued to between 58 - 72 ft lbs and the wheel just spins unless you stop it somehow. This was a two person job, and my bf did the spinning while I put my weight to good use sitting on the saddle. Between the both of us, we got it done.





Now the real fun begins: Getting the tire off the rim. If there are children present, you may want them to leave. What follows may be too disturbing for younger viewers. You have been warned.

I like your can do attitude and look forward to your ride reports!

Great job!

Thanks, KLX. My inspiration came from another inmate in Hawaii who took an old, rusted Honda Elite that I wouldn't have even touched and brought it back to life as a bastard Ruckus. Not my riding cup of tea, but his determination was remarkable.

If I can find the thread, I'll put the link here: http://advrider.com/forums/showthread.php?t=867934


That said, changing my tires kicked my butt.

I've never done it before, so naturally I checked out YouTube for pointers. Getting the tire off the bike was easy; it was getting the tire off the rim that was near impossible. The videos we saw made it look so easy to break the bead, so my bf and I set out with high hopes and all the necessary tools.



Turns out missing from that happy picture was the 800 pound gorilla, a Thesaurus for looking up new cuss words and a box of Kleenex for our bitter tears. All of those are needed for the first-time tire changer.

What is needed is the knowledge of how much force to apply where at the right time. If you've never done this before, you don't really have a good idea of these mysteries, and so you tend to flail away with misdirected fury. Soapy water is your friend. Here's the steps as we tried and tried...

Step one. Use a doohicky to remove the thingamajig from the valve stem.



Step two. Place ill-fitting red clamp on tire. Yes. It's got to be red.



Step three. Add lubricant. Windex, soapy water or even spit works. Here's where a rabid dog would come in handy.



Not really step four, but if you want to protect your rims from scratches, you can shell out for fancy rim protectors from a motorcycle store or you can do like my bf here and butcher and old garden hose and basically wind up with the same thing. Of course, after losing them inside the tire, I could appreciate why the fancy ones have strings attached.



Finally, after tugging, stepping and cursing, we were about to take a break and crawl into a wine bottle when the bead just sort of popped without any pressure at all. Kinda like fighting with a jar of pickles; at some point it just gives. We both actually laughed out loud at how ridiculous it made our previous efforts seem.



With the bead broken, it was time to bring the tire irons to bear. This was the easy part.





Gus approves our work.



Getting the new tire back on was simply a matter of reversing the deal with the tire irons, with a lot of soapy water to ease the way. Our stupid home compressor is on the fritz, so we have to take the tire to a local bike shop to "pop the bead" and re-inflate it to 28lb and remount it on the bike. Gotta love that free air!

Oh, and while the wheel is off the bike, it seemed a great time to make sure the lining was still within specs. It is, as you can see.



That's it for now. Any questions or suggestions of successful bead breaking methods greatly appreciated.

~ Tootles