Weird idle/throttle issue

[ClunkintheUK]

Sorry this is not for an SV but at YBR125. I can't find any decent YBR forums. I'm trying to sort out my missus' YBR so we can sell it. She hates riding it so its been sat for a few months.

Now when I start it up, its quite difficult to get it started on the kick, and the electric start doesn't work (i'll get that sorted separately). once it does start it struggles to warm up and settle down. Sometimes the revs just drop and it cuts out, or as it gets a little warmer the revs start climbing up to about 4-5k, but as soon as you put the choke in it cuts out completely.

If you try the throttle at any point in all this it cuts out. It's a carb model. I've checked all the hoses going to the carb, there is a little slack in the throttle cable, I am not sure what causes these symptoms so any suggestions of what to check would be great.

[Craig380]

Is the carb slide actually bottoming out against the stop, or is it sticking slightly in the carb body? You could try whipping the top off the carb and pulling out the slide just to make sure it isn't sticking or snagging. A very thin smear of engine oil from your finger around the slide when you put it back it might help.

Check also the carb inlet rubber, and the hose from the air cleaner for a possible crack or leak. When the bike's running, try and hold it at a steady 2,000rpm and spray WD40 onto the rubbers. If the idle speed drops then raises again, there is a leak / crack in the rubbers.

The carb doesn't have any electrical connectors on it, does it?

[johnnyrod]

It goes up to 4-5k by itself?

[ClunkintheUK]

Yeah, I had to adjust the idle speed way up to even start it.

I checked the air lines to then took the carb apart to discover the pilot jet was blocked with a load of crud. Cleaned it out with a strand from a wire brush and it started up just fine. Throttle does what it should again.