bogging at 4k rpms in all gears

1985 yamaha maxim x. 18k miles. carbs just cleaned. New air filter. mixture screws at 3 turns. She bogs in all gears right at 4k rpms. Only when she is in gear though. screams out of gear no problem. Any ideas on why she would do this??

 

Possibly clutch drag or perhaps the mechanical advance mechanism (if we have one?) is sticking. Should be some counterweights behind the rotor for the ignition. cruzerjd

 

Don't bother looking, you won't find one, the bike has electronic ignition and the TCI does all the advancing for you!

 

The Carbs were ether not throughly cleaned ... or, there is some issue related to the Diaphragm Piston Assembly's that was overlooked during reassembly.

A loose Top.
A folded-over Diaphragm

Certainly Diaphragm's sticking needs to be investigated.

Even if the Carbs were cleaned just 10-minutes ago. If some particulate has blocked the Metering Ports on the Emulsion Tubes; the performance will be drastically affected.

 

Was the problem there before you cleaned the carbs?
Does opening the "choke" at 4000 rpm get rid of the problem?
What do your sparkplugs look like?

 

the no 2 carb body broke on me and I jb welded it up on the top left corner of the diaphram. I'll bet that is the problem

 

plugs are new. don't know what it ran like before. I pulled the fuel filter and it now goes to about five thousand. I pulled the air filter and it goes to about 8 thousand, but still bogs. I'm betting it is a fuel delivery problem, so off are coming the carbs....sigh....

 

Now you know why some places are telling XJ-Biker's to "Take-a-hike" when they bring-in their bike for a Carb-related problem.

There just ain't an easy way around pulling-off the rack and getting-down to stripping the Carb Bodies down to the brass tacks and getting real familiar with all the members of the Hitachi or Mikuni Family.

It's too bad we can't just shake-up a nice, frosty can of Bud Lite and Beer Grenade 'em back to being Clean ... inside and out.

Now the good part of my Reply to your Post is that I'm sympathetic for you having to go through the toil and trouble of worst part about cleaning the Carbs ...

Getting them you-know-what's off the darn bike!

The bad part is ... some Forum "Visitor" is going to be scanning the archives, read this wrong ...

And, ...

TRY IT!!!

 

Hey Rick, altho I haven't been able to test it out yet, I found out that no 2 carb piston was rotated about 35 degrees out. Meaning it wasn't seated correctly. This was after quite a bit of testing in other areas. I took the carbs off, and instantly saw that the piston was rotated. It wasn't that bad to get them off. I've almost (until this bike) had long discussions with xjs on getting the carbs back into the boots that lead to the head. Maxim x's (this is my second, my dad has the first) seem to be the exception.

I must have mad the motorcycle gods mad today, for everytime I went to go for a ride to check this thing out, it rained. The last time I went out, my arai fell apart on me. Somehow the shield had broken, and the side cover to the helmet as well. It was one of those days...

 

That nuts.
I saw that same situation recently.

I LOVE the design of the Mikuni's Yam hung on those X-Bike's.

They're so nicely cast and machined.
If you pay attention to detail ... you can make 'em really put-on the power.

Press-out the Nozzles.
Scrub the Inside Diameter of the Bore that the Nozzle is pressed-in too with a small-bore, rifle-barrel cleaning brush.
With the Nozzle removed ... Blow-out the Main AIR Jet Passage with a long stream of Carb Cleaner.
Clean-out the Inside Diameter of the Nozzle, itself, by folding a Pipe Cleaner in half and twisting it tight to make a scrubbing tool.
Clean-out every single one of the 20, little, Metering Holes, in the Nozzle, by sticking a Welders Tip Cleaning Tool ... in one side and out the other.

Ruin a few pair of old athletic socks by putting the nicest shine you, the socks, your fingers, and a Can of MOTHERS ... can put on the BORES that the Diaphragm Pistons fit into.

Tweak the urine* (*other word for) out of it.

Fill your pants pockets and jacket pockets with small rocks.

That will help keep the front wheel from lifting-up too far!!!