1986 Honda Aero NB50 strange Auto Bystarter stalling issues.
Posted: Fri Jul 07, 2023 2:58 pm
Hey all! I just picked up a 1986 Honda NB50 and this is my first moped. Outside of some minor tinkering on a 73 Honda cb350 I have near no mechanical experience. I'm doing lots of research lol.
I figured out the Aero has a cheap Amazon carb, and the Auto Bystart was left unplugged. But it seemed to run fine by my standards minus some mid range jutteriness. It tops out at about 35 on flat and 40 downhill.
I decided to try tuning the carb after reconnecting the Auto Bystart and taking a 15 minute ride. I went through some steps from another post here to tune it.
Now I have the Bystarter connected, it starts fine, but until the bystart turns itself off the engine loses power and dies close to half throttle. Wider throttle is great, acceleration is pretty quick.
This issue goes away when unplugging the autobystart, which sounds wrong. From my understanding when unplugged the autobystart stays in the enriched "choke" state.
I have no idea about how the variator is supposed to feel when it shifts and rides, but I did pop off the cover and check everything out in there. The clutch pads dropped a lot of debris, but the pads looked smooth. I didn't have the right size to open up and look at the rollers to check for flat spots, that's on my todo list.
I'm hoping to address this issue and fix the speedometer, as well as gain some performance. I hear stock Aeros can get closer to 40 on flat if set up right.
Thanks for any info you guys have!
{Edit: corrected bypass to Bystarter for clarity}
I figured out the Aero has a cheap Amazon carb, and the Auto Bystart was left unplugged. But it seemed to run fine by my standards minus some mid range jutteriness. It tops out at about 35 on flat and 40 downhill.
I decided to try tuning the carb after reconnecting the Auto Bystart and taking a 15 minute ride. I went through some steps from another post here to tune it.
Now I have the Bystarter connected, it starts fine, but until the bystart turns itself off the engine loses power and dies close to half throttle. Wider throttle is great, acceleration is pretty quick.
This issue goes away when unplugging the autobystart, which sounds wrong. From my understanding when unplugged the autobystart stays in the enriched "choke" state.
I have no idea about how the variator is supposed to feel when it shifts and rides, but I did pop off the cover and check everything out in there. The clutch pads dropped a lot of debris, but the pads looked smooth. I didn't have the right size to open up and look at the rollers to check for flat spots, that's on my todo list.
I'm hoping to address this issue and fix the speedometer, as well as gain some performance. I hear stock Aeros can get closer to 40 on flat if set up right.
Thanks for any info you guys have!
{Edit: corrected bypass to Bystarter for clarity}