NOT STARTING...PLEASE ADVISE!

In the same boat and similar mileage too

 

well palmer650, It sounds to me like 1 of 3 things is happening.

1. Your carbs are leaking at the bowl ontop of the carbs there is an o ring in each carb that goes bad. Causing the fuel to leak down the caarb by the filter.

2are you jetted properly for your elevation, i.e. did ur dad live in montana and u took th bike back to nj. Cuz that could cause a random starting problem. Cold days it will start hot muggy days it wont.

3. The last one i could think off is a combo vacume leak with bad timing.
Check the valve cover gasket for any air leaks.

Oh did u fiddle withh the the idle screw that seemingly goes into the block under the carbs?

Best of luck mate, ull fugure it out im sure

 

here's my situation...

im having a bit of a hard time to start the bike. it needs a spray of fuel in the carbs for "faster" start-up, unless it'll drain the battery... when it starts. idling levels goes up then down then up until it shuts off...

tried to sync the carb's vacuum and had a hard time, until i read about the "YICS"

does the YICS / vacuum has any relation to a hard starting xj400z-s
OR does my carb still needs to be cleaned out again. (already cleaned it for about 5 times i guess)

inputs, comments and suggestions are all appreciated.

 

okay well ur problem seems to be a dandy one huh. Did you replace any jets when you cleaned the carbs? IF not try replacing the main jets and the idle jets. And as to the YICS i still don't fully understabnd it, but from what lil i know about it, its a design flaw. Make sure you do not have any air leaks on the carb boots,valve cover gasket, or base gasket. Cuz it still sounds like you have a a vacuum leak. Oh and did you check your fuel lines mabe they are clogged. Cuz by u having to spray ether in the carbs is telling me that you are not getting enough fuel on start up and then u get only miniscule amounts of fuel while idling. Just keep tinkerig on it youll get it eventually.

 

When the time comes to sync the carbs, the YICS port needs to be blocked off. The YICS port moves fuel between the cylinders and when you are trying to sync the carbs will throw off your readings. Chacal makes a YICS tool for doing this. Or you may be able to make one. Basically you need something to put into the YICS port on the side of the Cylinder jugs to block off that system.

As far as the starting problem, when the bike is at idle all the fuel goes through one very small opening right in front of the butterfly's on the top of the carb. On the opposite side of that hole is the Idle Mixture screw. When you put that in did you tighten that screw all the way down? The screw is right next to the enrichment circuit plunger attached to the bar that the "Choke" cable manipulates. The starting point for that Idle Mixture screw is 2 1/2 turns out from tight. If you tightned it all the way down there is no fuel going to the engine at idle. Something to check. Hope that helps.

 

One other thing that I forgot to mention, you said that you have cleaned the carbs several times. But something that gets overlooked is the starter jet in the float bowl itself. When you take the bowl off you will see a small brass tube that goes into a hole on the side of the bowl. Way down in there is a tiny jet for the enrichment or "choke" circuit. It is very easy for that jet to get blocked and if it is, you have no "choke" which will make it very difficult to start the motor. Something else to look into.

 

oo i forgot about that. listen to this guy he knows his carbs. I forgot u had 400 sounds like your carbs ar way different from 750 carbs

 

Umm... guys...

This thread is originally from 2008. I doubt the OP (Original Poster) is still fighting his issue.

SirMikel, we've been responding to your new posts. Please post your current questions in one of those threads too, this 4+ year old thread is in regard to a Hitachi-equipped 650.

 

If you are still having trouble starting that bike ... (Not uncommon inn late Fall and Winter) ... start your own thread.

We'll put this one to sleep.