Finally got the old steed up n running again. And low n behold, I’m here with what I hope is an easy diagnosis.

Ripping around the neighbourhood in 1-3 gear, running like a top. But if I get it good and warmed up, riding it hard in to 4th or 5th it runs great, but stalls out if I clutch and slow down.

My thoughts are, float bowl is running dry or idle set two low. But what do I know?

Wondering in what order, and how, you’d go about checking, and how would I adjust?

Dont want to chase my tail around this carb. Other than stalling out on deceleration, runs nice and pulls strong.

appreciate the help!

Clean the carb the tube from the inlet hose to the float bowl and make sure the pilot is clean and lastly the petcock can be full of stuff. How does it idle when you first start it firstly with the choke on and secondly when you shut the choke off. If it quits then it probably the pilot
Doug

Be good to hear & see it doing that. Not easy to record while riding. Video of it idling stationary & a bit of a rev then let it slow down to an idle & see if it stops.
Wouldn't like to guess without hearing.
You say 'Clutch & slow down'. I think i'm reading the wrong thing into that, but are you just coasting to a stop by closing the throttle grabbing the clutch.
Another thought--have you accidentally left the choke 'on' & it flooding it up while slowing.

Thanks for the input. 

Petcock is clean and getting good flow to the carb from the tank, new fuel. Idles great when it first starts with choke on, and also great with choke off. I can rev it good in neutral, or with clutch in, and it doesn't stall when I release the throttle and drop the revs down. 

The stalling only happens when I decelerate after riding at speed in third to fifth for a longer stretch (sorry don't have a tach so not sure the RPMs). When I pull off the throttle to start slowing down (with clutch lever engaged), the engine just kinda gently dies out. Usually I'm able to just reengage the clutch and bump start it back up. But not ideal when slowing down into an intersection.

I've got good power through the whole range of throttle. I've attached a photo of the plug. It's a new plug, probably ridden about half an hour. Not an expert at reading plugs but maybe this can help?

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Carb needs to be completely stripped, and very carefully cleaned with carb cleaner and compressed air. Then rebuild, check float level, and that the parts fitted are correct.

Thanks, the carb has been cleaned thoroughly and rebuilt.

So all considered, would this be the right process to approach this.

-Adjust float to allow for more fuel in the bowl

If problem persists

-Adjust idle screw to idle higher

If problem persists

-Look at adjustments to pilot screw

Thanks,
b

It probably isn't this, but what condition are the petrol cap seals in? Maybe do a short run with the cap open and see if the problem persists.

I'm with Uncle Al on the gas cap. Had pretty much the same thing happen to a 78'
DT125.
Loosened the cap and ran great. Blew it out with compressed air to find a spider hiding inside.
Kinda reminded me of a vapor lock of sorts. Motor just quits.
( * spiders love 2-strokes too .)

Is the gas cap venting working.. Its an easy test
Just a thought

Thanks again. Spark plug is new, and spark is strong. Will check the gas cap venting.
If this doesn't solve the issue, is this the right next moves?

-Adjust float to allow for more fuel in the bowl

If problem persists

-Adjust idle screw to idle higher

If problem persists

-Look at adjustments to pilot screw