o6 yz450 stalling alot

:ride: I just went for a ride yesterday and the bike seemed to stall a lot more than the last time i rode it. It would happen after restarting the bike to take off, rolling through a tight turn with the clutch in, and at low engine spped when getting back on the gas. I havent been out in almost a month and the weather was a little cooler then. I am wondering if the jetting could be the problem due to change in temp. Last time out was 80-85deg this time 100. The only changes to the stock jetting are a 48pilot jet, 1.5turns on the screw. Also I'm pretty certain it wasnt just me, because i let my buddy ride it and he had stalling problem too.

I went back to a 45 pilot jet from a 48, seems to be a lot better now that it has warmed up.

:ride: I just went for a ride yesterday and the bike seemed to stall a lot more than the last time i rode it. It would happen after restarting the bike to take off, rolling through a tight turn with the clutch in, and at low engine spped when getting back on the gas. I havent been out in almost a month and the weather was a little cooler then. I am wondering if the jetting could be the problem due to change in temp. Last time out was 80-85deg this time 100. The only changes to the stock jetting are a 48pilot jet, 1.5turns on the screw. Also I'm pretty certain it wasnt just me, because i let my buddy ride it and he had stalling problem too.

I talked to Ty Davis's mechanic and he told me that they run a 45 pilot. Also, maybe drain the tank and add fresh gas after you change the pilot. :ride:

I myself may change my 48 to a 45, but check your idle screw.

The bike idles no problem. but i dont think its at the speed the manual calls for(1900-2100rpm) it doesnt sound like it is going that fast. oh yeah the altitude is 2500 to 5000ft. 100 deg 20%humidity

I turned my idle screw out as far as I could without it stalling, then it sounded like it was struggling, so I turned it in half a turn or so. I don't know how to tell if it's at the RPM's the manual calls for, thats one tool I don't have. But it sounds strong now.

I don't know about your problem though, what does the bike do when it runs, does it sound like it may die out?

i put an hourmeeter/tach on wich helped me set my idle, i was new to a 4 stroke and stalled it alot till i got it set in the 1900-2100 range. it sounded to me like it was idling high enough but it was only idling at 12-1400.

Where did you get the hour meter/ tach, and how much

Yep, grab yourself a tach/hourmeter. It's also real handy for knowing when to do an oil change and valve adjustment.

I'm running a #48 pilot at 2.5 turns out at sea level in the cold(about 16C), and although it'll still pop after chopping the throttle, it's spluttery down low at very low speeds. A #45 should be better for you, I'll probably be going to a #45 when the weather warms up. It's not a bad idea to turn your idle up a bit to help it from stalling if you have to, so that the engine's creating a bit more vacuum to suck the fuel mix through.

Where did you get the hour meter/ tach, and how much

You can get a Yamaha one, or just search for hourmeter on ebay or the web. I'm using an ENM hour/tachmeter. I bought three coz they had a 50% off sale. I've got one on my pitbike too. I mounted one to the handlebars on my 450 but it only lasted 8hrs before a diode broke off inside, I think it was too rough of a ride there. They sent me a new one free of charge, but this time I mounted it to the frame (so the ride isn't so rough) with velcro strips, it should be ok there.

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