It starts and idles, but throttle stops the engine

My '85 XJ700NC is finally starting after about 3 weeks of re-wiring the bike from scratch! It idles beautifully at about 1K rpm's, and it didn't even need the choke to start the bike. However, when I give it throttle the bike just shuts off. Can anyone tell me what this is, or could you direct me to a good thread about this subject?

You should also know that I have a custom tank, so there isn't a PRI setting. I have also done away with the stock air filter, and replaced it with four small air filters off each of the carbs.

 

The Engine is not designed to run on an Unrestricted Supply of Intake Air.
I strongly suspect that the Straight Pipes and Pods has your Intake Mixture entirely too LEAN to Run the Bike upon coming Off Idle.

Get yourself some Aluminum Screen.
Cut a strip of Screen as wide as the Filter Element.
"Line" the INSIDE of your Pods with Screen to REDUCE the VOLUME of AIR through the Pods.

You will have to:
Re-Jet the Carbs and Adjust the Volume of Intake Air to FIND the right Volume of Air and Fuel for running the Bike.

Good luck.
Getting the Bike to run good on Pods ain't easy.
You can get it to run pretty good after fooling around with it for 15 or 20 years ...

But there's very few people who run Pods and Open Pipes that can say they're Bike runs great.

 

Rick is absolutely right in regard to pod filters; do a search on "tuning for pods" or "reverse engineering pods" to get a start. CV carbs aren't happy with unlimited intake air volume so it creates a lean condition and a tuning challenge. You will need to re-jet; unfortunately there is no "set" formula for doing so.

 

My wines bike does this too...with no modifications...unless you choke it for a long warmup. After it warms up well it is fine. I suspect a carb sync and rebuild may be in order (the intake boots are cracked with dryrot). 8O

 

Regardless, ...

After you Re-Jet ... you'll need to restrict the Air Flow through the Pods.
Adding a "Perforated Insert" might be a step in the right direction to solving the Pod Air Flow problem.

Companies like this one would have Perforated Stock prefabricated in sheets to cut-out and line the inside of the Pod.

http://www.mckey.com/docs/products/perfstock.htm

 

Wow, I read a lot of threads about pods and they sound very tricky. Unfortunately the previous owner installed them and there is no going back, becuase my bike is completely chopped at it is awesome.

With that in mind.....the rest of the bike is immaculate, so it is very possible that the previous owner re-jetted or that re-jetting was not necessary. It also seems odd that the bike would idle perfectly but cut out completely on the slightest turn of the throttle. What else other than the pods could cause something like that to happen? How can I confirm if it is the excessive air or somethhing else?

 

Pull the Plugs and line 'em up 1 ~ 4 and Post a pic of the Business ends.
Pretty much the whole bottom of the Plugs but showing the Center Electrodes.

If the Plugs are Clean ... You'll have some Jetting to do
If the Plugs are Dark ... You'll have some Tuning to do.

 

I have the same exact problem right now with my xj650 and everybody seems clueless on where to start. I have a vance and hines full exhaust and a kandN filter and the bike bogs and dies right past idle when you first give it throttle. I have been scratching my head for weeks and am ready to shove the bike off a cliff at this point.

 

Look at the Plugs!

I'd guess you have enough Pilot Mixture to Idle and not nearly enough to SUPPLEMENT the need for Fuel at precisely Off-Idle.

You need Pilot Mixture to Idle.
Supplemental Richness to sustain Ignition of the On-rushing Fresh Air preceding the Air/Fuel Mixture of Main Jet Supply.

Look at the Plugs.
If they are CLEAN or Really Light Brown ... Up-size to a Bigger Pilot Fuel Jet.

(Check for proper placement of the Air Jets)

 

I did step mine down from a 205 to a 195. I felt that the bike was running too rich. That plate that you talk about. Well the original carb has one, but the carbs I am using are from Canada and dont have a plate. I tried to screw the bolt in and put it on but the whole isnt even threaded. Could this be my problem. If I can get it to just start now. It would fire up every time. I checked the plugs and there isnt a hint of fuel, but fuel is flowing. I set my mixture screws at 2 1/2 out just like the manual says. Should I go farther out with my setup? The full exhaust and the kandN filter. I have finally got the cracks in the rubber boots sealed with Plasti dip and the carbs are now leak free. The silly thing is that the bike ran when the carbs leaked and now that I have them sealed off it wont run at all. This has been the craziest bike ever to get running correctly. If somebordy could please help I would greatful. I thought I was a tunning gurus because I have tuned on my R1 and never had any problems. It always came out close to where I wanted it and now its perfect. The xj I have about 100hrs into the process of taking things apart to check for dirt, changine gets, taking the carbs off 50 times just to put them back on for dissapointment every time.