Opinion on my jetting

[Midway USA]

I have bascially a stock Banshee with FMF Gold Series pipes and FMF Power Core II mufflers. I am at 1780 ft and mostly trail ride. Not a lot of places to run wide open all out. My main is a 270 the pilot is a 25 and the needle is in the top clip. I have had issues with the left cylinder fouling. Oddly when it was cold out. It seems to bog a little of idle but runs great through the power band and wide open. One buddy at the Yamaha shop said it needed a 30 pilot and the needle clip in the middle. Another buddy at the same shop told me to leave it be. I just want to make sure I don't burn it up and can live with being a little rich over being lean at all.

[Midway USA]

I have bascially a stock Banshee with FMF Gold Series pipes and FMF Power Core II mufflers. I am at 1780 ft and mostly trail ride. Not a lot of places to run wide open all out. My main is a 270 the pilot is a 25 and the needle is in the top clip. I have had issues with the left cylinder fouling. Oddly when it was cold out. It seems to bog a little of idle but runs great through the power band and wide open. One buddy at the Yamaha shop said it needed a 30 pilot and the needle clip in the middle. Another buddy at the same shop told me to leave it be. I just want to make sure I don't burn it up and can live with being a little rich over being lean at all.

 

Didn't do the altitude thing right. I am at 1013 ft. Am I anywhere close on my jetting?

[dajogejr]

What is your air filter setup? If you already posted it...I didn't catch it.

 

One cylinder fouling out could mean a few things.

Plugged carb, bad spark plug, ignition issue, carbs out of sync....list goes on.

 

How is the overall health of this motor? Good compression, etc?

[Midway USA]

What is your air filter setup? If you already posted it...I didn't catch it.

 

One cylinder fouling out could mean a few things.

Plugged carb, bad spark plug, ignition issue, carbs out of sync....list goes on.

 

How is the overall health of this motor? Good compression, etc?

 

Forgot to list the air cleaner in this post. It has a single K&N with an aluminum flow adapter. Can't remember the name on the adapter. The air cleaner box and lid are untouched and I don't plan to modify them in any way. This would be the second time I have had the carbs apart. The first time one pilot was plugged but nothing else. This time I looked the choke and its passage over by recomnedation of one Yamaha mechanic. No issues there either. The first time I synchronized I did it by eye through the intake. This time I noticed there were sight glasses on the sides of the carbs to see the dimple drilled in the slides. I ended up totally changing things by doing it this way and it seems to run much different now. The bog off idle doesn't seem to be there. Haven't been able to ride it hard yet. Through a bout of forgetfullness and stupidity last time I attempted to go ride I lost the gas cap. I am waiting on one to get here and it should be here in a few days.

 

The cylinders are fairly fresh. I had to repair a stuck ring when I bought it. We had just freshly honed the cylinders for the guy about a year ago and they got something in the right cylinder. It didn't harm the cylinder at all but squashed the ring land just enough to stick the ring. I went ahead and honed the cylinders a few strokes to make sure but the orignal cross hatch was still there. I took a jewelers file and filed the ring land to get a ring to ride free in it and smoothed the top of the piston. I have not checked compression and the cylinder that is fouling isn't the one that had the damage.

[dajogejr]

Remove the snorkel on the airbox....you have a pro flow adapter.

The jetting is fine, if not a little rich (Probably need 250 main with a full airbox setup).

Do NOT put 30 pilots in there.

 

You have an electrical problem would be my guess, if the carbs are cleaned out and working properly. It's not your jetting.

[Midway USA]

Remove the snorkel on the airbox....you have a pro flow adapter.

The jetting is fine, if not a little rich (Probably need 250 main with a full airbox setup).

Do NOT put 30 pilots in there.

 

You have an electrical problem would be my guess, if the carbs are cleaned out and working properly. It's not your jetting.

 

I hope it isn't electrical but could be. Based on the way I originally sync'd the carbs and the difference it made when I did it using the sight glasses, I am leaning toward that being an issue. The bog seems to be gone off idle now and the idle is much smoother as well. Before I couldn't let it just sit and idle to warm up without it dying. I let it idle for 10-15 minutes last night and it never died and the idle speed was rock steady.

 

As far as removing the snorkel, is it removeable or is it something I will have to cut off the lid? Not really wanting to cut the orignal box or lid. If I could come up with another lid I would consider it. Thanks for the help.

[dajogejr]

It comes right off. I"m not sure if it's a snug rubber boot fit or a hose clamp, but it comes right off with no other mods.

[Midway USA]

It comes right off. I"m not sure if it's a snug rubber boot fit or a hose clamp, but it comes right off with no other mods.

 

Cool!! Thanks!! I'll mess with it when I get home from work tonight. Hopefully my gas cap will come in soon so I can ride and test the latest setup. Later. Jerry

[Midway USA]

Didn't even realize what the snorkel looked like beacuse it was already gone. Got my gas cap today and went for a ride on the trails at the spillway. My carb sync was the whole issue pretty much from day one. It ran the best it ever has. Not as much smoke, no fouled plugs, more power, and no bog off idle. It was great to be able to enjoy a ride!! Thanks for all the input. Jerry