Bike is shop bound.....

[Guest]

Thanks guys. I drove out today to west 60 Cycle and bought a box from the salvage yard.....and what do you know.....IT WORKS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!

MIND BLOWN!! Carbs need synced, but it runs. And it runs strong. Backfires a little on throttle down but I can deal with that.

Once again thank you guys for given me a gentle kick in the ass.

Is it a backfire or just a popping sound? If it's a popping sound, your sucking cold air into the exhaust as you let off the throttle, thus causing the popping sound. Might want to check for hole in the system or a loose connection(s) somewhere.

[chuck hahn]

Or the backfiring could be timing, carb syncing, too lean or too rich on the mixture screws. Point is to check each and every one of these items. Where is the mixture screws set at now..when its back fiiring?? Most have found that 2 1/2 out from LIGHTLY seated is about right mand you fine tune from there.

By LIGHTLY seated we mean you turn the screws in easy and when they stop going in you DO NOT force or thighten them any more. Take a sharpy and make a mark in line with the slot and use that as a reference point to count the turns out.

The you can do the highest idle method to get a good sound. Set the ilde at around 1200 to 1500ish Start with carb 3 ( 3rd from the left side of the bike ) and slowly turn the mixture screw in till it starts to sound like its gonna stall. The turn it out and youll hear the RPMS go up. Watch the tach also as you adjust. Once its set at the highest idle it will reach, readjust the idle back down to the 1200 to 1500 original point and do carbs 1, 2 , and 4. reset the idle after each carb as you go.

[kdupont]

Its more of a popping noise.

When you say mixture screw do you mean the one that comes from the factory covered by a plug? Because mine is still plugged.

[chuck hahn]

The one on top and at the back of the throats.

[chuck hahn]

Take the tank off and hook up an auxillary tank. Be sure to plug the petcock vac line that comes off carb 2 also.

[kdupont]

Yea those screws are capped, Ill have to pull them out before I can make any adjustments. The only other screw I have access to is the pilot air screw?? I think is what its called, its on the venturri opening on the air box side.

Anyone use a colortune to adjust mixture?

[chuck hahn]

The one on the front is the air jet and that gets screwed in all the way and snugged down..not anything adjusted there.

[kdupont]

Those screws are turned out. Ill screw them back in.

[kdupont]

I turned the pilot air screws back in, pulled the plugs out of the mixture screws and adjusted the mixture to two turns out for starters. I also sealed the air box boots up right so theres no leaks. After putting it all together it wont start.

[chuck hahn]

You turned the pilot screws all the way in..as in the ones on the bottom by the bowls??? NO!! In your previous post you said the front of the venturie had a screw ( should be on the left bottom side ) ..thats the air jet i said gets tightened down and there is no adjustment for that!!


If you thightened down the BOTTOM screws and "snugged them" like i said for the FRONT air jets, you probably have jammed every needle tip in and broke them!!! For god sakes PLEASE PLEASE be exactly clear in what your describing to us.................FLUCK!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!

[chuck hahn]

From post #36...

"The only other screw I have access to is the pilot air screw?? I think is what its called, its on the venturri opening on the air box side."


This led me to believe you were describing the air jet thats on the front of the carb throat on the air box side...which in turn prompted my response that it just bgets screwed in and tightened down. If you jammed the bottom PILOT SCREWS down you may have broken all the tips off in them ports.

Nowhere did anyone mention to turn them in and leave them. Lets get some ternminology out of the way here.

MIXTURE SCREWS...The ones on the top rear of the carb throats that you can see from above when the carbs are on the bike.

PILOT SCREWS..The ones on the bottom in the back behind the carb bowls ( VM carbs )..you can not see them when the carbs are on the bike.

AIR JETS..The brass ones on the bottom left of the carb throats on the airbox side. You would be looking straight down the carb throats to see them.

Which one of the above 3 did you turn all the way in? AND if it was #2, did you get physical and really tighten them down like you would do when just putting in a bolt or something??

[kdupont]

I turned the air jet screws in. The bike started this morning and is running fine. Im missing two air jet screws. My mixture screws are fine and I don't see and "pilot screws" on my carbs, but I have CV carbs, not VM carbs. Where can I get replacement air screws?

[chuck hahn]

Take pictures of what you want and point to it please. You keep saying air jet SCREWS and there is no such thing!!!!!!!!!! You have air JETS and you have mixture SCREWS. The mixture SCREW is the ones on TOP of the carbs and at the rear behind the top covers.

Air JETS are in the front of the carbs throat at the lower left side. Brass slotted jet.

Which are you specifically saying are missing?

[chuck hahn]

These are air JETS and get tightened in and are not adjusted....



Back here is the mixture screws which ARE adjusted to tune the carb to the cylinder.....

[kdupont]

Air Jets are what I am missing. Im missing two of them. Bike still seems to run fine without them. Still would like to get them back in.