50MPH stall, then transmission won't work

[Jlovvorn]

Update:

Took it out tonight, and it started and ran fine.

Came back after 20 mins, and I discovered an odd thing.

When you rev the bike up above 4,000, and then let off, it comes down and stalls.

Bike died in the driveway twice when I repeated the process.

If you turn up the idle to about 2000, it will come down and near stall, and then bounce back up to 2000.

So you really can't run the bike at less than 2000 idle.

So I think the bike died as I decelerated because I let off the throttle suddenly.

So, once again, we have a fuel delivery problem. (or so it seems).

I did the timing and valves this afternoon (hopefully I got it right). The timing was right initially and the valves were a little tight.

Plugs now look brown and reasonably dark - which seems like progress.

I don't have a timing strobe, so I buttoned it back up and will get a strobe this weekend to check the advance and finish the tuning recipe.

I am going to redo the float levels next, as I think maybe the bowls are emptying at high RPM somehow.

The core problem I need to trouble shoot is that the bike idles at one speed, and then drops down almost 1,000 RPM right after revving up and letting go. It doesn't return to normal idle.

That means if I set it at 1200-1500 and drive off, I am going to stall during the ride.

Runs around no trouble at 1800-2000 idle setting.

[mike in idaho]

Sounds like possibly a problem in the low speed circuit of the carbs. The slow speed jets/passages are blocked and won't meter fuel properly & the idle speed screws are turned in so far,to get the engine to run, that the engine is actually running on the main circuit, that makes fuel delivery & idle speed very erratic. When you are looking at the floats, pull the slow speed jets out and make sure everything is clean.

[Jlovvorn]

Thanks.

I am going to pull them off and go ultrasonic.

I am tired of screwing around with this.

I have cleaned the slow jets and the rest of the parts 5 times.

The idle screws are showing about 3 threads, which seems pretty far screwed in.

[mike in idaho]

Are the slides in the right way around, cutaways facing the air cleaner?

[Jlovvorn]

Yes, but I will double check. That would be embarrassing.

[jensen]

Hi,

Next time when the engine stalls, pull the carb bowls, and see if gas is flowing.
If not, or not enough, check the in-line gas filters (in the carb) and clean them if necessary.

Jensen

[mike in idaho]

Yes, but I will double check. That would be embarrassing.

I've found bikes with the slides in the right holes but the carb tops on the wrong side, binds up the cables and causes things to act funny.