some questions about 85 maxim x

I wrote a decent sized post, but when I clicked "create thread" it said it wouldn't post because it was "spam like".
Edit: Okay, now that the thread has been created, basically I just bought an 85 maxim x and have a few questions about it.

First, does the maxim x have any type of fuel filter? I don't see one anywhere. I'm afraid I just clogged my carbs with stuff from my tank via sea foam. Stupid me.

For you guys with maxim X's, how hot do they run? Mine is only a shade below the middle line on the highway steady 65mph, all other times it's above that, creeping toward the red in town. Cooling fan does work. New coolant too. I'm actually kind of afraid it's running lean, if I don't just need a new thermostat.

Thanks for any info, I appreciate it.

 

Please understand that this site has (in the past) been the target of repeated spam campagins that were making it nearly impossible to see legitimate posts.
The limitations placed on new members were not taken lightly, and have resulted in a near lack of spam posts for over a year (which took several years to accomplish).

New members cannot link to outside websites or post photos until after their fifth post. There is also a limit on word count for those first five posts.
You should be able to post a paragraph per post until then.

 

Welcome to the forum, congrads on the bike. Even a X, the old water cooled bundle of joy

I think most of the bikes have a basic filter on the inside of the tank that is part of the petcock. Don't count on it doing much for you. A new filter put inline between the petcock and the carbs is the way to go. The ones with the gold in them that are see through are a good choice.

The X is a great bike, just make sure that if the valves have not been check for a while this should be done. Read up on it and take your time doing that project. The shims a the "under" type and a very small and look like a hollow pencil eraser. The air cooled shims are more like a quarter design.

As for the temp, I would just make sure your cap is on correctly, the coolant is in good shape. Have you tested the fan yet? Or should I say is your fan turning on when it gets warmer? As long as the fan is kicking in and the temps stays below the red line, you should be good to go.

 

The reason I bought this particular bike is that with 22k miles on it, it's still under the 26k mile first valve service. I figure 99% of people will not do the valve service, and will just risk their motors, I don't want any part of that.
Yeah, I don't have a problem with the anti spam strategy, I just wish I knew that before taking the time to write out a whole thing, I can't even remember half of what I posted now!

 

Anyway, what I'm really trying to figure out at the moment is what I just did with the sea foam. The bike ran fine before, good idle, response, good power, after I poured a little sea foam in, it ran worse and worse until I got home, now it sounds like it's not even running on all 4 cylinders, it bogs bad off idle, I even stalled it just twisting the throttle a little. I just I hope I don't have to tear the carbs all apart. I read a how-to showing the petcock rebuild, it doesn't look like there's any kind of filter built in to the petcock, I have no idea.

 

How much Seafoam to how much gas?

There is a large screen that's part of the standpipe assembly on the petcock, and each carb has a mesh screen at the fuel inlet (IIRC). Otherwise there is no filter.

As far as the temp gauge goes, that's normal (based on reviews and member posts). There is a different thermo-switch that can be used to make the cooling fan come on sooner, but I'd have to look up which one it is.

 

That's crazy to me that there's no filter. Thanks for that info, I was afraid of that. As far as the sea foam, I poured 4 oz of it (the "maintenance dose" recommended on the maxim x site for a full tank) to what I thought was maybe 2/3 of a tank, but I'm thinking now it was maybe closer to 1/2 a tank. I wish it had a fuel gauge. So I guess it would qualify as a "soft treatment" concentration, (1/2 can to full tank) but at a lower quantity, since it was only 1/4 can that I poured in. I haven't even owned this bike long enough to know how many miles it gets on a tank either.

 

Squidx, Welcome aboard!
Well there's no filter in the line, but the one in the tank and the "beanies" on the float valves are filters.
Adding a clear sintered bronze one is a wise addition and good insurance of keeping the fuel to the carbs clean.

As k-moe said, the temp gauge reading and cooling fan cycling is within the normal range.
The thermo switch can be changed to one that will cycle it sooner, but the fan will draw more on the battery at idle
because it'll be on a higher percentage of the time. Here's a thread on it:
https://www.xjbikes.com/forums/threads/maxim-x-radiator-fan-switch-modification-update.40133/

Top off the gas you have in the tank with some premium fuel. If you can get ethanol free in your area that's your best option.
Seafoam is a solvent and doesn't burn like normal gas and an over-concentration will cause your engine not to run as crisp and responsive as it should. Keep in mind that it won't correct issues with vacuum leaks, sticking slides, clogged pilot jets, or issues with diaphragms. Because the bike is "new to you" I would be thinking of doing a complete overhaul on them. That way you know their good and clean.

Also, don't put off the valve clearance check. That really should be addressed before fine tuning the carbs. I've come across ones with very tight clearances at even half the recommended interval.

Tony

 

I definitely will check the valve clearances, I set them on my old cummins and on my accord within the last year, although they didn't require shims.

But I know that's not the cause of this current malarkey since it was running well at the start of my last ride and then 20 or 30 minutes later after running the sea foam it's now running like crap. I will add some 91 no ethanol fuel and see how it runs then, I just hope I don't have to take the carbs all apart. Oh well if I do I guess. I definitely will add a filter. I just hope the sea foam didn't melt anything in the tank and send it into the carbs. Do you guys know what people coat tanks with to prevent rust? It's some kind of brown stuff. Hopefully the sea foam didn't dissolve any of that!

With the temp gauge, if this was a car I'd change the thermostat immediately, considering how it doesn't hold the temp steady. I'll do that later and update the results. But with this bike, I'm actually also concerned that the motor is running lean and overwhelming the cooling system a little. I really wish I had a wideband 02 sensor on it.

Last night I was reading the thread about changing the rear brake shoes, yikes! So are the maxim x shoes the same way? (held on with adhesive, not rivets, and with no machined surface on the shoe to hold the friction material from moving if it does delaminate?) I know this can be no joke, my dad's volvo 850 rear parking brake shoes came apart and locked up the left rear wheel, fortunately it happened at 5 mph about a block from the house. I took it apart and just removed the parking brake, I wanted to fix it properly, but he just wanted it out.

 

1. Assume that the rubber parts in the carbs are original. Rubber ages-out. It's best to service the carbs so that you know they can be relied upon.

2. You don't need an O2 sensor to monitor fuel mixture. Pull the plugs and read the color. If you really want to see what's' going on in real time, buty a Gunson Colortune. Either method is more than sufficient for setting a proper fuel mixture.

3. Yes, the rear brake shoes are held on by adhesive. Check them.

4. (I cannot stress this enough) Check the date codes on the brake lines, and plan on rebuilding the whole system. You have what is essentially a sportsbike engine in the frame of a cruiser. Stopping is far more important than going.

 

Brake lines are 1985, 34 years old. Any recommendations on pads? I was looking up some ebc pads last night, they come in a variety of grades for the front pads, but I guess only offer one grade from the rear shoes.

Out of curiosity, I just did a little test with some sea foam. I poured about half the can into my push mower's half full tiny gas tank, and proceeded to attack tall, wet grass and weeds in my back yard. My hypothesis was if sea foam is a lousy fuel, and doesn't burn as well as regular fuel, the mower would run badly regardless of whether the carbs had varnish or anything to be dissolved. But the mower ran fine, as I went up and down row after row. All I noticed was a little blue/white smoke at shutoff. So I bet I will be going into the carbs on the maxim x, despite the previous owner telling me they were "gone through" when the tank was coated, a year ago. I know they were, the screws are all chewed up, but I also know whoever worked on it was a complete moron. They didn't even install the correct airbox to carb boots, they glopped silicone all over it trying to seal it up, the boots didn't even fit on the carbs. I had to order new ones. They also let it leave the shop with the right side upper frame bolts completely missing, I replaced those with some bigger ones from a parts store. (I ordered the factory yamaha ones and they are way undersized, loose in the holes, no wonder they're known for falling out)

 

welcome to the DPO
dreaded previous owner

 

If you haven't been yet, the link below will take you to a very sueful site. The archive is full of good info (linked on the notes page).

http://www.maxim-x.com

 

There's a thread for that:
https://www.xjbikes.com/forums/threads/previous-owner-masterpieces.57929/

I mentioned in a previous thread recently that a lot of previous owners are barely competent enough to add gas and check tire pressures.
Sounds like you'll have a few things that need to be addressed before it's truly safe to ride.
I see the frame bolt issues on the Fazer models too as they have the same set up. Red loctite is your friend on those when torquing.

EBC HH pads are a great upgrade for the front. Remember to get two sets, one for each caliper. Gotta rebuild the calipers and master cylinder too. Also, Len at XJ4ever.com (our resident parts guru) has a stainless braided line kit option, as well as standard lines.

The rear brake shoes are only available as standard replacements, but be sure to get the best quality ones you can afford.

If the tank was coated it may be degrading, and could be causing a fuel starvation issue. I have trusted Caswell coatings for the kits on the ones I've done. Biggest issue in your case would be getting the old liner cleaned up so it's prepped properly.

Tony

 

Oh, I forgot to mention that I discovered the intakes and o-rings in the condition pictured below:

 

Oh, I forgot to mention that you may discover intake o-rings in the condition pictured below:



Make sure you check them while you have it apart. Maybe yours won't be that bad, but you don't want to be chasing a vacuum leak after resetting the valve clearances and going through the carbs.

Tony

 

Welcome to the forum , definitely up grade to the stainless braided steel brake hoses and go to top if page click on xj4ever ordering parts seems strange at first but do it a couple of times and is easy. Chacal offers great service and parts are first class quality . The other thing read the information overload hour lots of good info. Cheers

 

Yesterday I pulled the tank off and dumped the fuel out. The tank liner looks good, not coming apart or melting or doing anything weird, but the filter/standpipe thing was just floating around in the tank, not in place on the petcock. It actually does look like a decent little filter though.

I've also been trying to research stainless brake lines, I looked in the xj4ever catalog and they're $175 + shipping, hmm. I guess apex makes a kit but people give them bad reviews, say the fittings rust, the lines fall apart, etc. Galfer makes a set for the xj700 maxim, I assume the x700 and the xj700 "X" use the same lines, they're $123 + shipping ($136.80 total) so I might just pick those up. Still researching the brake pads and shoes.

I also bought a windshield, I might install that later today and post up a couple pics here.

 

The standpipe is plastic, does not filter well at all, and can be either replaced, or staked back into place (dimple the inner sides of the mounting boss with a center punch) depending on the condition of the thing.

Rebuilding the Yamaha Vacuum Fuel Valve w/pics

 

seafoam is a safe stabilizer. on their web site they soak seals in seafoam for several years with no affect. it will help clean the carbon out of the cylinders as far as a carb cleaner it is useless. it is more of a fuel stabilizer for winter storage.

manual says not to be concerned about temp reading unless it goes into red zone