Maxim X POD install

I have a 85 Maxim X that i recently purchased in non running condition. I have done the following to the bike.

*Cleaned and bench and wet synced the carbs
*Installed pod filters due to the airbox boots being missing as well as a cracked airbox.

The bike started and ran great once the carbs were cleaned and with a towel over the intakes, and before you say anything i did not rev the bike was just there to add resistance to the airflow.

I installed the POD filters when they came in the mail and tried to fire up the bike. it would start but idle low so i fine tuned the idle and found that it was only running on the inner two cylinders.

I am aware that i need to check my valve clearances as well but i will address that later in the post, i would like to get it running well enough for a test drive to check the transmission before i really dig into the project.


I was able to take the bag that the filters came in and use it to block off the airflow through the PODs and it began to run on all four.
I am wondering if i will be able to get any closer on a vacuum sync with it running on the inner two cylinders.

I know that i need to buy the jet kit as well but I feel that it should atleast idle on all 4 without the jet kit. Has anyone had trouble with getting all cylinders to run at idle with PODs?

Also i was able to use a coat hanger trick to check and replace the valve shims on my 550 without too much trouble, is it possible to do that on these 5 valve engines?

 

First step
Remove PODS
Second step
INSTALL STOCK AIRBOX

And your problems are SOLVED!
YAAAYY

 

Sounds to me something in carbs still not set correct or clogged. My 82 xj650 has pods, 4 into1 and started up fine after carbs been gone through and cleaned even with 110 mains 40 pilots. After test drive, installed 122 mains, made huge difference no flat spots but still a little lowend hiccup...but will be installing 41 pilots...this all AFTER checking valves....

I haven't even synced carbs yet and runs/idles fine...waiting to install pilots then final tune everything. Plug chops of now are tan/chocolate colored but thinking I might shine needle to get just a tad more fuel (richer)...


No xj expert but I would check valves first in your case then compression, then carbs again. That's my 2 pennies.

 

You should experiment with increasing the size of the AIR Jets.
Especially, the MAIN AIR Jet.

The AIR Jets on Mikuni Carbs are at 3 O'clock & 9 O'clock on the Inside Diameter of the Intake Horn.

http://www.motorcyclecarbs.com/Mikuni_A ... 97_C65.cfm

 

Unfortunately not. The shims are located under the buckets on the "X" motor; to replace them you need to remove the cams.

 

Well i guess i will be pulling the cams to check those valves, i would like to get a test drive in before i tear into the topend, if there are any other problems i may take the time to pull the engine and rebuild it.

Any other suggestions to get it to run on all 4 so that i can at least take it for a test ride?

Also what do you guys think about the dynojet carb kit, i know it may need fine tuning after the kit but is it a good place to start or are there better jets to chose to start tuning, and do i need anything besides the kit, i am not sure if it comes with air jets.

 

Hold on now. You don't pull the cams to CHECK the clearances; you pull the cams to swap shims. You can check the clearances the same way you would have on the 550; it's when it comes to actually replacing shims it's different.

 

See even I learned something on this post!
Ive always wanted an X

 

The "X" is the first-gen watercooled, 20-valve FZR motor shoehorned into a Maxim.

Some of the maintenance items are a beeotch. In RETURN, you get much extended valve-clearance intervals and--- well, an FZR in Maxim clothing.

But proper maintenance is extremely important; it's basically a half of a Formula One race car motor from that era. Yamaha was helping a couple of F1 constructors with the five-valve combustion chamber, and technology flowed both ways.

The "X" took the "racebike for the street" idea to a new level.

 

OK, lets check on some basics. You said the bike didn't run when purchased and you've cleaned the carbs. Carbs are on and it fires up. BTW, these bikes will run without an airbox, but not very well.

As you stated, it started and ran fine initially before the pods. However, with 38K on it, I would be checking for overly tight valve clearances and/or for an ignition problem. Both problems tend to be worse as the bike is warmed up, however the ignition troubles will keep it from idling properly when it misfires.

If you haven't gotten one already, get yourself a repair manual. And, if you have moderate mechanical experience, you'll be able to check the valve clearances yourself. If any are out of spec, make sure you follow the proper procedure as it will require removal of the cams and lots of patience.

Once that's done it's on to the ignition. The outer two cylinders on the X are fired off the left (drivers) side coil (#1 and #4). The inner two are fired off of the right (passengers) side coil (#2 and #3). This could be a combination of a few things. A coil that's no good (cracks causing it to ground out). Or, no power feed to the input terminal that signals the coil to fire coming from the CDI (not a common problem). Bad spark plug wires and/or high resistance in the plug caps, causing a lean misfire.

Next time you start it, after the valve clearances are done of course, pull a plug wire off one at a time to see if that cylinder dies off. Hopefully this will help you pinpoint your troubles.

Now, as far as pods and tuning go, I would recommend sticking with the stock air box. The stock airbox intake tubes act as velocity stacks and are critical in providing the proper airflow signal through the airhorn on CV carbs.

Tony

P.S. Shameless Plug: I have a complete airbox set-up for the X model with a K&N filter that's ready to install if your interested.

 

You should grab that Airbox and Tune-up that X-Bike, ... stock.

Once you get the Valves in specs and those Mikuni's Cleaned and Clean-tuned; you can tune that baby to pull hard and get high-on-the-tach quick.

Clean the Carbs, ... thoroughly.
Polish the Diaphragm Piston Bores meticulously!
http://xjbikes.com/Forums/viewtopic/t=1 ... rt=15.html

ColorTune the Pilot Mixture a little beyond the Blue. (Slightly Rich)
Get out-of-the-hole like a sprinter.

You can dial that bike in so that you can let the other guys see your brake-light come on when you go light-to-light.

If those Coils are acting-up, get-rid of 'em and buy a set of high-performance Coils from DYNA or ACCEL.

Get that bike on the hairy-edge and you'll have a blast playing with the guys who ride street-fighters.

 

As Rick said:

Both of my X's were purchased in non-running condition. You do take a risk, but is well worth the time and effort. Here's some inspiration:

A video of the 700X before I sold it.

And another of my current 750X that has approximately 39K on it.

Both bikes are set up with a K&N and an airbox modified for additional airflow. That mod does require slight jetting upgrades.

The X's, when properly tuned, are a blast to ride and surprise most anyone that dares to mess with you.

Tony

 

I am planning on building a homemade manometer tonight so that i can atleast try to get the carbs closer in sync and see if that helps, I know that it is 1 and 4 that are not running due to temperature of the exhaust pipes, they are cold. Like i said it started to fire on 1 and 4 when i introduced a restriction to the pod filters so i believe that it is vacuum related, wether it is the valves or maybe i did a bad job of bench syncing the butterflys. I am aware that i need to measure the clearences before the cams come off.

How much would you want for that airboxs?

 

Cold pipes on 1 and 4 are usually an indication of no spark on those cylinders.
Don't mess with the carbs until the ignition is working properly.

PM'ed you on the Airbox.

Tony

 

when i put pods on the 750 x , i had to go up quite a few sizes on the main jet before it would even rev out.

was surprised such a difference pods makes in the jetting.

also, the valve clearances shrink over time. so what this means is that eventually the valves will never close and the bike wont start; or have a hard time starting.

since shim availability is so rare, i actually (gasp) filed down the top of the shims until proper clearance was achieved.

 

Hey Tony
In your YouTube vids you mention the Dyna Coil upgrade, do you still have the part number around.

Cheers, Graham

 

Graham,

I did the Dyna Coil Mini's on both my bikes, and I sourced them through E-Bay at this retailer:

Dyna Mini Coils DC1-2

Much easier to install on the X compared to the standard Dyna coils. If you decide to get a set, let me know. I can walk you through getting them set up on your bike.

Tony

 

The Quick Test for a Bad Coil is:

Un-plug the Coils.
SWAP the Plug-ins to the Wiring Harness.
Plug the 1/4 Coil into the 2/3 Harness
Plug the 2/3 Coil into the 1/4 Harness.

If you had 1/4 not firing BEFORE you swapped, ... and 1/4 IS firing AFTER the swap and 2/3 are dead, ... If the Signal from the Box is OK at the Harnenss, ... that Coil is bad.

 

Ok after spending some time in the cold with my bike today i was able to get the carbs in tune as well as fgure out the running problem. It seems that the problem was with the mixture. I began to back out the mixture screws 1/2 turn at a time and found that it finnaly started to run well with the screw out over 5 turns. I guess Jets in store for me before i can even take the thing for a ride.

I know that i can buy jet kits, but the ones that i was looking at do not come with pilot jets so i would have to order those sepretly. Do you guys recommend the jet kit or is it a waste of money. I can get the jets for much cheaper but i will not be able to get the adjustable needles, as well as the "Proper size drill" for the venturi holes.

Any recommendations on what jet sizes to get or whether or not to purchase the jet kit would be extremly helpfull.

 

That you have the Pilot AIR Screws -- 5 Turns Out, ... means they are Wide Open.
You should probably "Up" the Pilot FUEL Jet to regain a Fine Tuning feature.

Increase the Main AIR Jet.
Add some new Air Bleed Holes in the Main Nozzles.

Experiment with different sized Holes at the Bottom of the Diaphragm Piston.
Punch Holes in Wafer-discs of Brass Shim Stock to sweat on the Bottom of the Diaphragm Piston to alter the size of the Vent on the Piston's bottom.

A Leather Punch Set would cut a hole in Shim Stock.

http://www.rjtool.com/12pc-leather-holl ... 4Aodj2cA-w

 

I like the idea of using shim stock to resize the vents at the bottom of the diaphram piston but that is something that will help with fine tuning of the midrange and i have to get the main and pilot jets set first.

When you say Up the pilot jet i am aware that it needs to be richer, and from what i have read it should only be brought up +1. Is this +1 in the pilot jet going to be enough to compensate for the extra 2 1/2 turns that is needed on the mixture screws to bring it back to factory setting?

Also i have read a number of things about the main jet that are recomending increasing from +2 to +4 is there a better one to start with.

 

It's great that you got it running. However, don't get ahead of yourself in trying to set up the carbs without verifying the basics. Make sure your valve clearances are within spec, the compression is good across the cylinders, and your ignition is in top condition.

With that said, the fuel delivery to the idle screws has to be good and the tapered seat for the tips needs to be clean (a pipe cleaner and a wooden BBQ skewer works well). I'm sure you replaced the idle screw o-rings/washers when cleaning, and also cleaned the pilot fuel delivery circuits, so you're probably all set there.

Let me just say, your in uncharted territory when tuning for pods, but I'll try to help. What size pilot jets are you starting out with, 35's or 37.5's? I've seen both on the X carbs, and it will help in determining which ones you need. Going up one size will help get you in the ballpark. But make sure you dial in the mixture screws with a colortune, and you've verified the basics previously mentioned.

And, before you spend any time on setting up the main jets (which are probably 105's), be sure to check the emulsion tubes and verify they aren't worn out. Going up a size at a time (107.5, 110, 112.5, 115, etc.) to get the mixture dialed in at the upper rpm range. Like you had said, only then you can start working on the diaphragm hole size and needle position for tuning the mid range. Keep in mind that any tuning you do in cold weather will likely be off when warmer temps hit in the spring.

Any carb kit will only give you a baseline to work off of, so getting an assortment of jets will be your better option. Check on the parts and jets you need by hitting up Len at info@xj4ever.com.

Tony

 

For what it's worth, I've got an '85 Maxim X Canadian version (750) and pods. It runs well, I've got 117.5 jets in it.

Note that vales are in spec, colortuned slightly rich at idle and sync'd. I'll note that the inner two cylinders (2&3) show signs that they are running slightly more rich. Probably due to less air getting to those cylinders.

 

Mikey,

That sounds about right on the 117.5's, although each bike, including altitude you ride at, will require individual tuning. And, by the way, the mains can be staggered on your bike by running 115's for 2&3 to help with the flow imbalance. Matter of fact, I run a size up on 2&3 on mine because the design of the stock airbox with a K&N flows more air to the center two cylinders, which is just the opposite.

Tony

 

Keep in mind, ...
No matter what size Main FUEL Jet you install, ... the problem you face is getting the Main Jet Fuel siphoned up and out of the Main Nozzle (Emulsion Tube) into the Intake Air at the right Volume AND atomized sufficiently to make power.

Consider installing a set of Mikuni Short Velocity Stacks.
You can get them Screened or "Improvise" ... and figure-out some way to marry the Pod to the Stack in order to Speed-up and Shape the Intake Stream from turbulently swirling into the Carb and becoming a fast-rushing column of air.

http://www.google.com/imgres?hl=en&clie ... 2,s:0,i:90

 

OK so i have finaly got the carbs off again to check the sizer of the jets.

Here are the stock sizes,
Main 105
Pilot Fuel 35
Pilot air 140

From my calculations i need to up my main jets 2 sizes, and my pilot jet 1

Does this mean that it goes up from a 105 to a 107.5 or two steps up to a 110
also on the pilot jet, i would go one step up to a 37.5 there seems to be no one number up

Also do these seem to be a good place to start or would someone recommend different sizes?