Too Rich OR Too Hot Outside?

[syscrusher]

The garage is getting pretty close to operating temperature this last week from the heat outside but I found that my 93 VR will start without the choke.

Does this confirm that it's adjusted too rich or something stuck or just fine?

 

It seems pretty weak after starting, almost like weak spark or missing. All pipes get hot, probably more hot if leaner, huh?

 

I had just two bars showing on gas gauge and added nearly full can of Sea Foam to gas. I went for short spirited rides for a few days letting it marinate over night.

I think the carbs are clean now. Engine didn't really seem to mind that level of SF when I was riding it.

 

I'm just wondering what I should expect. I noticed the choke thing when it also didn't run fast with choke full on but as I reduced the choke there was a point where it would run faster. Before I reduced choke it ran very rich each time with a smoky toxic smell of carbonizing combustion. I thought I'd try to see if ran without choke and it runs slow, around 600rpm. It needs a little throttle to fire but then it'll run slow at first until it's warm. When it's warm it doesn't seem weak anymore.

[lonestarmedic]

Mine will start without choke and run about 600. Warms up and the about 1000. And yes, warm weather a lot less choke. Full choke sends a lot of fuel through the carbs. Mine likes about 1/3 for a few minutes when first started. Maybe 2-3. It sounds like pretty normal, especially for hot weather. Think maybe you have been applying too much choke in the past. These bike carbs do not have a choke butterfly like an old carb on a car. When you choke the Mikuni carbs it pulls a plunger out that opens a passageway that allows more fuel in. Texhnically an enrichment valve. And the motor will run on a fairly heavy Seafoam mix. Just gets poor mileage. Maybe you had dirty jets and got them clean.

[MasterGuns]

It was so hot here in Aledo that my temp gauge was up to normal when I turned the key on first thing in the morning. No choke needed then either. Just kiddin.

[syscrusher]

Mine will start without choke and run about 600. Warms up and the about 1000. And yes, warm weather a lot less choke. Full choke sends a lot of fuel through the carbs. Mine likes about 1/3 for a few minutes when first started. Maybe 2-3. It sounds like pretty normal, especially for hot weather. Think maybe you have been applying too much choke in the past. These bike carbs do not have a choke butterfly like an old carb on a car. When you choke the Mikuni carbs it pulls a plunger out that opens a passageway that allows more fuel in. Texhnically an enrichment valve. And the motor will run on a fairly heavy Seafoam mix. Just gets poor mileage. Maybe you had dirty jets and got them clean.

 

At 1/3 my choke never seemed to do anything. It always took about 28 seconds before I had to move it from full choke to 2/3 to keep it from revving too high. I'm amazed that now full choke just makes it smell bad and run a little crappy but not revving fast as it always had before. Thanks for the Mikuni info, my DR650 also has a TM40 Mikuni with the enriching circuit.

[lonestarmedic]

Hmmm, I start full and drop to half within about 2 seconds.

[lonestarmedic]

1/3 gets about 2000 rpm cold for me.