82 750 Maxim issues

Hey guys, had to chime in with some questions about my new XJ addition. I got this bike in trade for an old laptop. It registers just over 12,000 on the odo, but it's in pretty rough shape. It's been dropped and beat up a bit, but most of the damage, from what I can tell, is cosmetic. Dents in the tank, broken needles in instruments, scrapes here and there. But I took the bike knowing that it had running issues. So here's what I've got to work on.
Everything appears to be in stock form, but of course, the stock airbox is missing, as is the right side cover. I don't know what the obsession is with killing airboxes. I have been able to get it to start, but I've had to keep the choke wide open the whole time. I'm getting some strange noises from the starter area, but if I pull the starter and give it power, it sounds good, the bearings feel alright, and I've pulled all the plugs and tried to turn it over with no load, and it sounds fine. The sound is like a sloppy bearing rattling away right at the starter or the starter clutch. I plan to have the starter rebuilt anyway, as it's kinda weak. But would like some thoughts on that.
Ok, so on to the running issue. If I jump start the bike, I do have to crank for a good while before it fires, and it will fire up, but on first start it seems to blow back through carbs 3&4, mostly from what I see it's #4. It has a pretty heavy hesitation as well. I have pulled the carbs and cleaned the main places as it did have some gelled fuel in it. Maybe they need to soak. Anyway, my experience with backfiring has generally been a timing/spark advance type deal. Could this be an issue on the XJ, or do I just need to give the carby's some more attention. I'm trying to locate a stock airbox to put back on it, just need to track it down. I've read quite a bit about the importance of the airbox, and maybe it's the answer to the whole deal. But the starter thing is a bit of a bugger. Let me know what you guys think.

Thanks!
Scott

http://picasaweb.google.com/freewings/1 ... directlink

 

hey i have a stock air box. actually i have 2.lol one off of an 82 650 Seca and the other off of a 83 750 maxim but the air boxes are the same. i don't think its an air box problem. maybe the float levels are off or you just might need to soak them. There are very very little holes in the carbs that if they get clogged they can do that.

 

Well here's where I stand at the moment. I have ordered an airbox from ebay, which should be here this week, but something just hit me. I have read too many times that people hacked these things up to get them out, so how much fun am I going to have getting it in there? The new lights are here, and the mirrors ought to be here this week too. I also plan to try to get into the carbs tonight and be sure they're clear as well, again. Anyone had experience in getting these airboxes in and out without pulling the motor or chopping them up?

 

I'm going to be installing one later this week. I'll post here on how it went.

MN

 

Sounds great! Thanks!

I'm also going to have to replace the instrument cluster as it's in pretty rough shape as well. Broken needles, and peeling LCD film. I'm thinking about a set that I saw on JC whitney, just a basic speedo and tach. I think I recall someone saying that there may be some wiring involved, which I'm not afraid of. But as I research these posts, can anyone point one out that's particularly informative? Hopefully I'll find it today on my own, but we'll see.

Thanks!

 

If you can, you should obtain the schematic for your beast and sit down with the schematic that should be furnished with your new gauges and then play match up. There will be extra wires left over from the stock harness, you just need to cap them off. I'd be happy to walk through it with you provided you can send me good pictures.

 

I started on the electrical stuff last night, since my airbox still isn't here yet. I hope it gets here soon. Anywho, I installed the new turn signals last night, and they look great, and also swapped the headlight from my 81 XJ550 (round) with the one on this one (square) and am very happy with the change. I didn't swap the whole bracket, just the buckets and they fit perfect. Also was able to utilize some left over mounting points for my driving lights as well, and they will replace the old aux light.

I have the Hayne's manual for this bike, and I know they have schematics on there, I just hope they're good enough to get this done. We shall see.

 

Haynes Schematics are pretty good. I make copies so I can trace out the circuits if needed and keeps the original clean from my shop grime

 

Very good idea, mine's in PDF form, so I'll print them off instead of getting the lappy all greasy

 

I have a stock schematic that the original owner got from the dealer for my bike. I can try to scan it in and send it to you but the thing is in kind rough shape (wat you you expect for a 27 year old piece of paper)

 

That would be great, I'll PM you my contact info.

Thanks!

 

Also, since we're talking gauges, I'm looking around for different styles and such, where have been some good sources that you have seen? I can't go expensive, but I want to track down the basics. I need a speedometer, preferably with mileage tracking and a trip, or, if no trip, a fuel gauge so I can keep an eye on that. I'm also considering installing a temperature gauge at some point as well, just to keep an eye on things. To me a tach isn't important, since I shift by sound, not number. I'm peeking through the galleries for ideas too, just thought I would toss this in.

Thanks!

Scott

 

There's a thread here where a user swapped his gauge needles with ones he got from a Ford at a junkyard. He did this as part of a project to swap the bulbs in his gauges with LEDs.

As for the LCD film, that's been dealt with, too.

 

Cool, thank you for the links!

 

Alright, finally got the airbox and mirrors last night. I was able to install that airbox with little trouble. Only took about an hour with removing the carbs and boots and battery box, and putting it all back together. I may have to hook up the old cluster just long enough to see if I can get it to run, but I'm in the process of deciphering the schematic and preparing to begin the wiring work over to get some aftermarket gauges on here.

The mirrors were a different story. The new mirrors are perfect, nothing wrong there. But the brake handle wasn't threaded properly; should have been left thread, instead of right. So I'm working on swapping the controls off of my 550 for this as well. Right side, no problem, done. But I'm having to work a little harder to get the left side off. Looks like I'm going to have to slip the grip off to get it off. Anyway, there's the latest progress, and hopefully I can get this thing started tonight.

 

The reason I posted those links was to hopefully get you to the point where you wouldn't have to swap out the gauges. If the LCD film and the needles are all that's wrong with the gauge cluster... then those can be fixed.

 

I may still go that route until I get further along. My intent in replacing them is simply cosmetic. But for the moment, I'm going to attempt to repair it and just get running, then worry about the cosmetics later. I simply prefer a very simple, but uniform look about my bikes. The 750 is so round in it's body work (minus the lighting) and I'm attempting to further accent that roundness overall. That's why I've installed the round headlight from my XJ550 onto this one, as well as replaced all the turn signals with round ones instead of the square ones. It's just an attempt to satisfy my thirst for consistency. I plan to tear into that cluster tomorrow while it's raining up here, and see if the speedo and tach still rotate, or if they are firmly rusted up, since the clear cover is cracked as well. We shall soon see....

 

I hooked everything up last night, and tried to start it, and it tried, once, ran for a few seconds, and I let off the choke and killed it. Now it won't come back. I guess I'm going to have to soak these carbs and give em the good go around. I have to have this thing ridable by August for a trip I'm taking to Richmond, IN. We'll see how close I cut it to my deadline :/

 

Alright, an update with good news finally. I almost have the wiring done, so the new turn signals will be operational soon. And, I got the carbs all cleaned up, and it's no wonder it couldn't run. I forgot, when I did the initial cleaning, to clean the emulsion tube in the center. Big dummy. They were terrible. Got everything cleaned up, and reassembled, and was able to get it to fire right up. Didn't have to choke it long, and and it was purring and sounded great. I need to have the starter rebuilt, since it's making some bad noises when starting, either it is, or the starter clutch is. I'm PRAYING that it's the starter. Still working on the gauges, but they are second in priority, since I'm trying to prep for a group ride on the 8th, if I can make it reliable by then. I'll keep posting my progress as things go!