3rd day on the forum

From west tn and just want to say hello. Picked up a 700 maxim a short time ago off craig's. Has the hatachi 33 mm carbs and was reading some last night on here about adjusting the pilot air jets. Can anyone tell me how this is done? My other bikes have mikuni and keihin and the air screw is out in the open under a plug. That does not seem to be the case with the hatachi and my service manual says nothing about setting them. It looks like the ones under the diaphragm are the air jet but this cannot be where you adjust them.

So any help would be appreciated.

 

between the carb and engine you'll see a brass hex thing with the enrichment plunger going into it, beside that is a hole with the pilot adjustment screw in it or a cap covering the hole.
the screw isn't far down under the cap, careful with the drill.
when you get the cap off, the screw is in for lean, 2-3/4 out is a good place to start

 

Well I called myself looking but must have overlooked them. I saw the choke plungers (which is not really a choke but an enricher but I am old school and still call them a choke at times) but did not see the caps. I will have to look again tomorrow.

I have removed the caps before to set the air jets on my other bike and somehow the caps were useless. I mean they are factory anti-tamper so you will not fiddle with the adjustments. However when I popped the caps and counted the turns till seat they were way off and all were different. Now this bike had 10,000 miles on it and the caps had never been removed but one was over 4 turns out and one was almost all the way in. Of course when I got the bike it had not run in 7 years and one of the pilot jets the seller could not get out so he decided to sell it. That was the GPz.

The 454 had the caps already removed and the seller said he had already cleaned the carbs so I would not have to go in there. When I saw that he had the carb vent tube hooked up the the vacuum fitting of the petcock I figured I had better take a peek at those carbs. It is a good thing I did as they were a mess and there is no way the bike would run like that even though he said all it needed was a front MC.

 

WELCOME to the asylum from another from W TN!!! Where ya' located???

skillet

 

Just finished cleaning my '85 XJ700 N hitacha 33's and I have all my pilot screws set at 1 3/8 turns open. Like you, when I first removed my carbs for cleaning I found the pilot screws set anywhere from 5 open to almost closed. Turned out that the one out 5 had a bad intake gasket and was sucking air requiring the and very rich pilot screw setting. I discovered this using the colortune plug where I got no combustion on that cylinder at 2 1/2 turns because it was so lean. Have no idea why the others were set where they were. By the way, I started with mine set at 2 1/2 and that was very rich for my bike. I've measured all jets and needles and everything is stock.

 

The mixture screws were set the way they were from the factory because they used an EGA and tuned a brand-new, fresh motor so it would run CLEAN and pushed it out the door.

Now here we are, 30 years later; and nearly none of us EGA-equipped.

SO: If you want it to run right, you get the valves in spec, and set the carbs at a "baseline" mixture setting. Then you vacuum sync, and if you use a ColorTune, you have a "visual substitute" for the EGA to fine-tune the mixtures.

Except you don't care about hydrocarbon emissions, you want your bike to run right.

And the motor is now NOT "fresh" anymore, has had its valves bed in and be adjusted, etc...

So those 30-year old factory settings are worth about...

8O

 

Skillet I live in tipton county.

Yes I know the purpose of them being capped but was surprised they would change that much on their own since they still had the anti-tamper caps on.

I did find the plugs and managed to drill through one before I broke my drill bit. The bit was dull to begin with and I was pushing trying to get that #2 holed when it snapped. I picked up a couple new bits and will finish the job tomorrow. Those caps are thick brass, not like the thin steel ones on my kaws. They also were disguised really well as to their location. The one I did open the screw was set at 2 3/8 turns.

I checked the valves and have 3 that are a little tight. We are talking .0003 or less as the .0040 would go but the .0045 would not and the manual gave a minimum of .0043 on the intake. Weird that they would all be on the intake. Now I am going to have to pop those suckers out and see what size I need. I want to set them as close to maximum as possible so they will not need redoing for awhile.

The bike runs decent other than a fantom miss on #2. I checked the compression and it was around 160 and checking the fire it was a nice blue but the plug was wet. Also the #2 was the only one that had proper valve clearances. Definitely a carb issue.

 

I live in the Shelby Forest area...

skillet

 

Horn Lake MS here.

 

Welcome.