Surge at low rpm

[5str48]

Just bought an 88 1500 that starts up beautifully and runs smoothly. However, it surges at low rpm and idle, otherwise runs great. I'm not too familiar with this bike so I'm open to suggestions as to where to look. My guess is a vacuum leak, bur not sure.

[Snowmoer]

Sounds like the recall was not done back in 89. Look just above the foot peg on the frame on the right side when you are sitting on the bike. There should be an X marked on the frame if the recall was done. My 88 did not have it done. You need to pull the carb and replace the pilot jet with a #55. It came from the factory with a #50. All the kits out there come with #60, but these are to much. Putting in a #55 will fix about 95% of the surge. It did on my 88.

Here is a link to get the correct jet.

https://www.jetsrus.com/a_jet_kit_stree ... 8-1991.htm

It is also a good idea to replace the S shaped vacuum line that is under the carbs. These dry out over time and cause problems. You can still get them from Honda.

I replaced most of my vacuum hoses when I had the bike apart. Some were drying out and cracking, so I did it so I would not have to tear the bike apart again. All these hoses are metric, and they are not found at your local auto parts store. I found mine in bulk on Amazon. Look on a parts fich and it will list the MM size of the hose you need.