What is the logical order of things to do to make my '81 650 Maxim the best it can be?

You guys have all pointed me in the right direction so far. I want to make my bike run the best it possibly can.
What I've done so far:
-Cleaned gas tank rust
-Cleaned and partially rebuilt carbs including new needles and main fuel jets (didn't do the vacuum sync yet)
-Added pod air filters (because my bike did not come with the boots that go between the air box and the carbs, but I still have the air box)
-Replaced intake boots (aftermarket Damineding boots seem to work well and were made in the non YICS orientation)
-Replaced fuel and vacuum lines, added fuel filter
-Oil change (my new oil is black after 950 miles)
-Added a fuse box (it didnt have any fuses at all) and a battery (motobatt)
-Chased some electrical gremlins around with tape
-NGK Iridium spark plugs
-Replaced front brake line with SS lines from Hel
-Rebuilt front brake caliper and master cylinder (do you use sintered brake pads or organic? I used sintered.)
-Changed tires to Metzeler Cruisetec
-Cleaned rear brake and added the wheel spacer that some PO lost and nobody told me about.
-Reshaped the seat, added a gel pad, made my own leather seat cover because I'm too cheap to buy one
-Adjusted clutch free play (I haven't seen anybody here mention this, but mine was all wrong I rode around like that for a while and now its fine)


The bike runs well enough to haul me around, but I think it could pack a little more punch and probably get better mileage if I worked on it more and tuned it up better.

Up next, I plan to get the valve clearance check kit from Chacal. Is there anything else I should do while I have the valve cover off? When I changed the spark plugs, what I could see of the piston heads looked like a BBQ. Should I think about doing a top end rebuild? I can see that there is a leak on the exhaust side of the valve cover.


I also need to fix the slow oil leak, it's leaked about 1/2 of a quart (an eighth?) over the last 2 months. I have 2 gaskets coming for the oil filter and oil cooler, I think that's where the leak is.


I'm planning on waiting until riding season is over for me here in upstate NY to do the valve clearances, and whatever else the experts here recommend that I should do to get this bike running the best it possibly can.

Thanks for your help everybody, let me know what you think I should do or what I've done wrong or missed.

 

The oil filter o-rings never get changed and they get hard and leak.
A bit of carbon on the piston tops is nothing to be worried about, as long as the bike is running fine. You can add some Techron to your gasoline or fill up with Top Tier gas as much as possible and that will clean the combustion chambers for you. Seriously, it's about the only fuel additive that isn't snake oil.
Google for Techron.

 

My $.02: Some things you might want to consider, may or may not be needed, but made a big difference for me:
1. Steering head bearings
2. Wheel bearings
3. Speedo - clean and lube the speedo clutch and gear unit in the front wheel, clean and lube speedo cable, replace if speedo is "jumping bean"

 

Do your valve clearance check first and swap replace shims if required. Then do a compression check before considering any top end work. Engine is unlikely to need top end repairs. Valve cover bolts rubber rings, you could replace them and the gasket if you have any oil leak at the joint.

 

start by doing all the routine Maintenace on the list

this would be oil filter and related o rings and crush washer.
check valve clearances. bring into spec
clean the gas cap and ignition switch.
clean controls elec contacts.
inspect and lube all cables.

look at brake systems rebuild calipers and master cylinder.
ohm out ignition system and charging system

make a list of repairs

cleaning carbs and replacing all o rings and shaft seals.

 

If the bike was run without the spacer or even just torqued together without it I would be worried about damage to the rear wheel bearings.

sorry to tell you this but that means putting the airbox back.

I would also replace those bolts holding your exhaust in place with the OEM exhaust studs and nuts. You don't want to stress those aluminum threads in the head more than they can take.

 

Simmyis right , if you want your bike run right the stock airbox is the way to go xj4ever has the airbox to carb boots . My opinion PODS suck on CV carbs on flat slide carbs they are fine . You will end up changing jets and might run okay one day and not so much another day. Good luck .

 

Fork oil/seal change and steering bearing replacement while forks are off. The aftermarket o-ring that came with the parts store filter was not very robust when I changed and it leaked the same way so ordered a handful from Len and no worries since.