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Honda Aero 125

Posted: Thu May 23, 2013 8:44 am
by mikep317
Hi Honda fans.
I am at my wits end. I have a 1984 Honda Aero 125. I had Honda shop bore and I installed new piston and ring set. Now scoot starts and runs great-for 5 minutes. Then it dies and will not restart. Plug is wet(fuel). I it sits overnight it starts right up and runs 5 minutes again. I cleaned carb, looks ok. Spark is not super great but ok. Compression is about 100 or so (piston/rings not broke in yet)

Is the bystarter bad? If so is one avaialable for this antique?

What replacement carb will be a bolt on replacement?

Any help would be greatly appreciated.
Mike

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:06 am
by swimmingfree
start it run it till it dies the check the carb and see it it has gas in it by using the dran screw on the bottom of the carb...
swimmingfree

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:20 am
by mikep317
Carb is full of gas after stalls- seems the carb is flooding the motor after 5 minutes. Bystarter?

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:22 am
by swimmingfree
have you done a test on the bysteter???
swimmingfree

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:28 am
by mikep317
I am doing today- 10ohms right?

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:31 am
by swimmingfree
dont no for sure i test them with a tape measure... i pull it then measureit put the power to it let it setwith the wower to it and re measure it shood be longer...
swimmingfree

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:35 am
by breaze
Double check with the service manual but that sounds right - service manual available here:

http://www.hondaspree.net/phpBB3/viewto ... 11&t=17085

There is an elaborate vacuum test in the manual but I've found that the simplest way to test is to connect the bystarter to a 12 volt battery, wait 10 minutes, then check to make sure the needle has protruded about 1/8" further. The idea is that the needle and collar/slide protrude to block off the passageway just like turning off a manual choke.

I've found that setting the bystarter by a ruler and noting where the tip of the needle is when you start works well.

Re: Honda Aero 125

Posted: Thu May 23, 2013 9:52 am
by mikep317
THanks guys- I will check today. I saw a Mikuni vm 20 carb will bolt up- I may try that next.

Re: Honda Aero 125

Posted: Thu May 23, 2013 12:26 pm
by nhaven
Unplug one of the wires to the bystarter. Run the scooter. If it still runnning after five minutes, then the carb is still clogged somewhere and your bystarter is most likely in good condition.

Re: Honda Aero 125

Posted: Sat May 25, 2013 12:21 pm
by DeathByFox
I have an aero 125 in parts and live by ohare airport if your interested.

Re: Honda Aero 125

Posted: Sun May 26, 2013 8:47 am
by mikep317
I took the bystarter off and connected it to a battery. It Slowly extends about 1/8th ". Still starting problem. CDI box?

Re: Honda Aero 125

Posted: Sun May 26, 2013 8:49 am
by mikep317
DeathbyFox
I may want to look at your scooter parts. Any pics? I may need carb and /or few other things.
Mike

Re: Honda Aero 125

Posted: Sun May 26, 2013 9:39 am
by breaze
Sure sounds like it is idling based on the bystarter supply of fuel, then bystarter warms up, closes off, and idle circuit in carb is not sustaining the idle. Especially if it has to sit overnight to crank again (bystarter cools off and opens again)

Hard to say for sure, but I would re-check/re-clean that idle jet.

Re: Honda Aero 125

Posted: Fri May 31, 2013 9:53 am
by mikep317
Guys- Success! I gave up on original carb and found one on Ebay- $29! Direct bolt up, original air filter fits like glove. I have to fix up a choke lever but runs better than it ever did!

Re: Honda Aero 125

Posted: Sat Jun 01, 2013 8:05 pm
by motormike
mikep317 wrote:Guys- Success! I gave up on original carb and found one on Ebay- $29! Direct bolt up, original air filter fits like glove. I have to fix up a choke lever but runs better than it ever did!
Please report back to us all Mike, after you've put some miles on it.
I will never go back this route, but the future owners of carb-less Aeros will be wanting to know.
I know of another who has tried this cheap carb and had less than perfect results.
Best of luck.... :hi: