Misfire at idle and low rpm

[azvampyre]

I got an old 92 blaster from a debt, but it misfire at idle and very low rpm. I rebuilt the carb and noticed the stock silencer (everything stock except a k&n filter, stock airbox) was hallowed, no packing at all.
Can this cause it to misfire and sputter at low rpm?

 

[Zwiser]

stock silencers have no packing just baffles and is it jetted for that k&n filter

 

[azvampyre]

stock silencers have no packing just baffles and is it jetted for that k&n filter

I just used stock jets which is what k&n product support insisted. Should change the main jet?

I noticed just now it smells like gas when I idle it to operating temperature.

 

[Zwiser]

yeah probably to a 250 or 260 and that probably wont do any thing for your misfire and hows the compression, any leaks, how are the reeds, are you using fresh 91/93 octane gas, good premix oil, new spark plug (br8es gapped at .32), is the expansion chamber clogged (if it was sitting for a long time could have mice in there)

 

[azvampyre]

yeah probably to a 250 or 260 and that probably wont do any thing for your misfire and hows the compression, any leaks, how are the reeds, are you using fresh 91/93 octane gas, good premix oil, new spark plug (br8es gapped at .32), is the expansion chamber clogged (if it was sitting for a long time could have mice in there)

I checked the reeds. They look new, but they're different from the ones on my 05; yellow instead of black and see through.
Put in a new be8es factory tapped; I'll check the gap tomorrow.
Using Royal Purple synthetic 2-cycle at 32:1 mix and RP max-cycle 10w40 wet clutch formula for the transmission.
The compression is 118 on the stock engine; I have a rebuild kit made by WSM I'm going to do after Christmas.
I didn't even look at the expansion chamber, could mice actually get in there, lol?
I'll get a leak down tester tomorrow to have on hand, where can I get one?
Thanks.

 

[Zwiser]

holeshotman sells a good one for $35 shipped just dont use compressed air even if the pressure is turned down itll pop the crank seals right out and 118psi is probably your problem since you have a piston kit already i say just keep running it and is the oil injection blocked off

 

[Zwiser]

and yes mice will craw down your silencer and make nests in the pipe if it sits for to long

 

[azvampyre]

and yes mice will craw down your silencer and make nests in the pipe if it sits for to long

Hey, thanks for all the help. And sorry about the slow response, there's no internet in Tonopah, 50 miles into the desert, so I'm on an Android.

Yes, it had the oil injecting block off when I got it. I took the RH Crankcase cover off to rebuild the starter and replace the Gaskets, and saw it had the plate and two ports on the cover were plugged with silicone. The carb just has a hose from the injection with a screw in it and only the left side drain tube, not the right, but I didn't think it mattered.

 

[Zwiser]

clutch cover side drain tube is soppused to be free of any cloggs

 

[azvampyre]

clutch cover side drain tube is soppused to be free of any cloggs

It may be clogged. I'll clean it and order a new drain tube.

 

[Zwiser]

you dont have to order a new one just blow threw it and see if its clooged

 

[azvampyre]

The clutchcase side never had a drain tube, so its possible the drain pipe is clogged with dirt or grease. I guess they put it there for a reason.

 

[Zwiser]

ok yeah then buy one

 

[royalt67]

low rpm misfire....try cleaning your carb again, especially the pilot jet and airbleeds.

You might want to run through the ignition checks in the manual, too (page 7-9). A weak coil or defective plug wire could contribute to a low speed misfire yet be masked at higher rpm.

 

[lowkhalbalr]

low quality fuel = preignition. ima have to go with royalt on the coil. remove it and ohm it out. coils should be zero.

 

[azvampyre]

Put a new reed gasket on after Xmas. Not sure if it was a coincidence, but it quit sputtering. I was going to replace the coil and wire just because its 19 years old, but I couldn't find one online.
But now I need new tires. The dirt road to my house had 4 feet deep water across it, so I went through the desert to get around it and plowed through a cactus patch masked by some tall bushes.

Anyone know where to get the cheapest wheel/tire combo?