Trouble with 86 Maxim X

I have a 1986 Maxim X that I am doing everything I can to get it up and running. This was going to be my very first bike. I didn't want to spend much because I thought I would lay it down and didn't want to be out that much OR I thought what if I don't like it. Well I got the bike and was told it was in perfect working order....it wasn't.

After practice riding the bike in my yard (it's a big yard), it was starting to sputter and I could smell gas. When I parked it, it started to leak. I am not what you call mechanically inclined. So I took it a motorcycle shop and let them work on it. They fixed the leak buy rebuilding all the carbs.

Now here is where the trick comes in. When I took it to them there was WAY!! to much flow. It was pouring gas out. Now, they say that it doesn't have enough vacuum to pull gas through. They are telling me that I need the original air intake. Now, I don't know if they are right or if they have done something wrong and just don't want to fix it. I am attaching a picture of the bike. Hopefully, you can look at it and tell me if the air intake that is on it now should be ok.

I have contacted some salvage stores and may have found an original air intake in CA but I live in NC and that is a heck of a lot of cash to bring in for something that I might not even need.

That is everything that I could think to provide, but if you have questions please ask. I do not have the bike with me. It is still at the store. I could drive it home but it needs gas shot into the air thing to start it and then I have to keep revving it to keep the gas coming through. If I let it die, which I did once, it sometime will fire back up, but if it doesn't on the first try then you can forget getting it to crank again with out shooting some stuff into it.

 

I would say the problem is with the pet cock, it needs very little vacuum to operate, unless it is split, also the fiter in the tank may need cleaning ( it's fixed to the top of the pet cock.

 

The mechanic is probably refering to airflow. Since the bike has airfilters on each carb it is drawing more air than a stock air filter box, therefore it it running a very lean air/fuel mixture. This will make for poor acceleration and throttle response. Most people who install these "pod" filters don't change the carb jetting to compensate for the added airflow. While it does look good it makes the bike run like crap.
I had a Maxim X with the same setup and it was difficult to get it to run properly. It took many tries changing the carb jets .
You have two options now;
1) remove carbs and rejet,remove carbs and rejet,remove carbs and rejet,remove carbs and rejet,remove carbs and rejet,remove carbs and rejet, yes you'll have to do this many times. Pod jetting is a trial and error process.
2) Find and install stock airbox and intake.

Post your location in NC, there are many XJ members here, maybe there is one near you.

 

I live in Morganton, NC. Hopefully I will be able to call Tuesday and find out if the original air box is in CA. If so, I will have it shipped out down here. With the rejetting though, and this is just due to my lack of knowledge, how would they go about doing this? Or is this something that they probably know they could do but just don't want to do it?

 

First, welcome to the forum, 2nd welcome to the world of P.O. lying piece of shit bastards.
Now that I've vented.....
Before you try and start it and ride it anymore, pull a spark plug and see what colour it is, actually pull them all. Then take nice clear pics and post them up for us to see. My understanding is these bikes were set up lean originally from the factory to comply with pollution controls in place at the time. So if the "Nice" P.O. just stuck a set of pods on there it could lead to major mechanical failure.
Also, if it was pissing gas that bad, unscrew the oil filler cap and take a good sniff, if it has a gas smell to it, stop riding period until you have the petcock sorted and done an oil change.
Now, what is your wrenching skills on a scale of 1 to 10? Do you have a manual?
There are a lot of knowledgeable folks on here that will go to no ends to help out a fellow XJ'r, but we do need to know some things in order to help out.
There are not a lot of shops that can deal with these older bikes, you may have better luck advertising locally for a retired mechanic that knows older bikes, or even go to a track that has Vintage racing as they may have more than a passing understanding of your bike or at least know someone that does.
Keep us informed on how it goes, it'd be nice to see another X back on the road. They are not really rare, but you rarely see them.


Cheers, Graham

For example, this is how mine looks right now (sigh)

 

See that picture right above my post? That is pretty much what you have to do to get a stock airbox in or out of this bike. I had to rebuild the top end of my bike, had the carbs and cylinders off and still could not get that airbox out. The motor was still in the way. For what it is worth I just thought I should tell you that.

Another thing you should do is do a compression test before proceeding. If that turns out bad, IE one or two or all cylinders down below 100psi (130-150 is considered very good if I remember correctly) then the least that needs doing is a valve adjustment....that takes expertise and from what you said you will not be able to do it. IF some valves have no clearance then valve lapping or grinding will be necessary, for they probably will leak even when closed now. You did not mention how many miles are on the bike, that could be telling also. Never buy a bike like this without doing a compression test or taking it for a good ride to prove it is running perfectly.

Sorry to be the bearer of bad news, but it is looking like there may be much more to this than you bargained for. Do the compression test first that will tell you a lot. If it is good, then get the valve lash checked and adjusted if necessary, then on to the carbs even though they are rebuilt they still could be a bit finicky, or that possible petcock problem. When these are running good they are a sweet ride.

Ps. You will also need new rubber grommets to fit your carbs to that airbox, old ones shrink and harden...Add about $50.+ for them. IF it were my bike I'd try to make it work with what you have.

 

Hopefully they will have the stock airbox, it would make it much easier. Install it and ride, after all thats all you want. A reliable bike to ride.
There really is no set forumla for jetting carbs for pod filters. It is not something you want to start paying a shop to do. It will take several attempts to get it right and lots of money.

 

Hey dustyt28655
Below is a post I sent to another member with the exact same issue you have, how to get the airbox in without pulling the motor.
He tried my suggestion and it worked for him. Take a look and see what you think.
It's still a lot of work, but that in itself will give you some better ubderstanding of how things work on your bike. But, like I said in my previous post, try and find someone with knowledge of older bikes, because unless you are independantly wealthy, a Columbian drug lord or have a job that pays retarded (sorry for not being PC) money, taking it to a shop will at least cost a bunch for labour, at worst they'll screw up the bike even worse because they have no idea what they are doing.
Good luck with the project and keep the pics and updates coming.
On a side note, my bike has been sitting like that for months due to trying to renovate my Mum-in-laws house for renting, and yesterday I took a nose dive down the basement steps and now have a seriously sprained ankle that requires me to stay off my foot for at least 3 days and expected recovery time of 4 to 6 weeks!!
In other words, expect the unexpected!



From: Maxim-X
To: tumbleweed_biff
Posted: Sat Jun 18, 2011 2:31 pm
Subject: Re: Hello ... maybe an assist?
Hi Michael
I've posted the engine removal sequence out of the Yammy service manual. I don't know if you can take any short cuts but I'm pretty sure the rad, exhaust and carbs will have to come off for sure. Any nuts and bolts should be sprayed with KROIL before attempting to dissassemble anything, especially the exhaust studs as they have a tendancy to break. I'm thinking that once the other stuff above as well as the frame side rail is removed except for the rear motor mount, with a small jack and block of wood, see how far you can lower the motor in the frame. You may be able to laeve the drive sahft attached as it will pivot a little bit as the motor tips forward. That's about all I can think of, here's the link:

http://s192.photobucket.com/albums/z90/ ... 0TECNICAL/

 

NONE of this is something you want to pay a shop to do, it will get expensive QUICK.

The X-Model engine requires camshaft removal to adjust the valve clearances; but they can at least be checked without pulling the cams.

Reinstalling the stock airbox requires a LOT of disassembly and might even require pulling the motor. However, it's still preferrable to the alternative, (trying to get it rejetted to run correctly with the air filters that are on it.)

Old bikes are NOT a "turn key" proposition; even moreso one like this, that's "halfway" modded. You're going to need to learn to do a lot of the required stuff yourself or you'll end up spending 4X what the bike is worth, and it still might not be right.

 

I think your problem may have to do with you not having petcock. I have an '86 and the petcock/gas vavle is on the left side just in front of that big ugly nut someone stuck into the bottom of your tank. The petcock switches your fuel supply from "reserve" to "normal' then to "prime". If you have no valve/petcock then you are run fuel constantly to carbs as if it were in "prime' mode on the petcock. Sounds like some "expert buggered it up good. good luck. If its any consolation you would have probably had to rebuild the petcock anyways, because of the age of the bike.

 

Sorry for the lateness of a reply I have had some issues with my dad being sick, but any who.

The bike does have a petcock I'm pretty sure it isn't the original, but it does work. I did order an original air intake from a salvage shop and it is on it's way being sent to me.

Once it gets here and installed I'll tell you if it fixes it or if we have more work to do.

Thanks for all your replies!!

 

Can you get some good pictures of the petcock that is on the bike? If it looks like a "big nut" it may be a pingel. If it is, they are usually manually operated and has to be turned off whenever you park the bike, otherwise you could get any amount of gas bypassing the float needle and seeping down through the cylinders and filling up the crankcase.