Reviving my 81 xj 550 maxim

Still had to weld up the tips of the mufflers. The exhaust was rusted all of the way around. The drilled exhaust I did when I was young and didn't know better.





I found some galvanized conduit to sleeve the exhaust and then welded it in.



That ought to help with back pressure. I'll probably plug the holes with JB weld. I would just weld the 1/4" holes shut but I can't get a piece of copper behind the hole to weld against.

I bought some exhaust paint and painted the mufflers. It felt weird sanding them down and not polishing the crap out of them. I'll have to be careful with them until I get the bike started to cure the paint. The wife won't let me use the oven to cure them. Something about the smell in the house blah blah blah.
Over all they turned out good







Gonna paint the collector next but it needs cleaned up more before I do.

 

Nice work so far. Isn't it fun welding anything galvanized? :lol:
Gotta ask, why all the work on the mufflers when you could just buy some aftermarket ones for 30 to 60 bucks or some uesd Sportster mufflers on Ebay?

 

Thanks.

Couple reasons:
1. I'm cheap
2. I've got the welder so why not put it to good use?
3. I just want to return it close to stock back pressure.
4. Would rather spend the money on carb and valve shims/tools.

I will eventually get some different muffs further into the build. Don't want to dump money into a bike if I can't get it going.

It has 29,744 miles on it. I never did the valve clearances & I put 9,000 of those miles on. Chances are, neither did the other owners. My valves could be hashed.

 

I have side panels ill sell you for ten bucks plus shipping, seeingthat you don't have them

 

Thanks for the offer, MotoMat, but I do still have mine. They're not going back on though. Do you happen to have an extra #2 carb body? I'd gladly buy that from u.

 

I picked up a cb 750 tank while hitting the salvage yards this weekend. Only cost me 10 bucks so if I ruin it, oh well. It probably sat there for at least 10 years. I heard liquid sloshing around in there & when I took off the petcock it was all varnish. Good sign. No water = no leaks (hopefully). Don't know yet if I'll modify the tank or the frame to fit it up. That will come once I get it running. Some picks of the mock-up. It still needs to move about 2" down and 2-2.5" forward. The front tank mounts are holding it up. They either need cut off the frame & skinnier ones welded on or the front inside of the tank will need to be cut out & patched.

+ my yamaha key opens the tank cap! Must be a simple lock.

 

I hope you do modify that tank to fit the bike, I think it would be a nice look. I am also curious as to how you would go about that. I would be interested for future projects of mine. Do you mod the frame or tank?

 

Don't know. Could go either way. If i did the tank, I would need to braze over my welds after. I'm still in the planning phase but that original tank will not be what I end up with.

 

I am just unsure of how moding a tank would be done. I could weld up a tank, but I am afraid I would have a bunch of poris holes, I guess brazing would fill them in. If only I could affored a tig.

 

Someone put a Honda tank on an XJ before with little mods. I think it was Schooter, look through the threads. I'm sure you'll find something helpful in there somewhere, best of luck.

 

@ Haysersys: a tig would be mighty nice. I think my dad has one at work he can use so I may do all of the fitting and tack it all in then have him finish it off. I've had a hard time dialing in my Hobart 187 handler mig for thinner guage metal. Even very quick tacks I can blast right thru if I'm not extremely careful. I got it for working on the thicker metal on my jeep.


@OnB: I'll look for that thread. I'll definitely have to pound in some of the bottom of the tank to clear the 2 frame rails in front of the seat. As for the front mounts of the tank, it may just be easier to drill the spot welds on the frame mount to pop thos off.

I'll still look for other tanks. I really dig the boxyness of XS500, RD 400, SR2 or the old Honda dream 50 cc tanks.

 

Got my carb parts on order so I need to get my exhaust back on this weekend before the parts come in next week.

Does any know what material the header pipe to collector gasket is? 1 of them disintigrated during tear down. Was thinking I would use some fiber glass wrap or some cork paper (for making your own gaskets).

 

You can't really make your own.

They're metal rings, filled with an asbestos-like material. There are two "styles" and I included pics of both styles here, toward the end of the article: http://xjbikes.com/Forums/viewtopic/t=29356.html

You really need to replace them with the correct parts.

 

Oh, I'm sorry, you said "header pipe to collector."

Those are a similar composite part made of special material; again something you really can't make yourself.

Don't have a pic of one handy.

 

Iii don't have just the number two, buut I do have have a completely dissaasembled and freshly cleaned and machine boilded carb rack, guranteed to have all the piieces minus gaskets

 

Ok, I'm ready to fire it up.

As of now I have, COMPLETELY (except for throttle shafts) disassembled/cleaned/polished/reassembled carbs. Polished slide bores, cleaned all passages, emulsion tubes, Replaced all 4 pilot jets, Replaced all 4 needle valves & needle valve seat o-rings, added all 4 washers and o-rings to the pilot mixture screws (they were missing when removed) and reset to 2.5 turns out, checked diaphrams for pin holes (all good), replacement #2 carb body from chacal (thanks), floats set, all 4 carbs bench synced with business card strips, Marvel Mystery oil in each cylinder for over a week (turning engine over manually every day), bike had new plugs already (from PO who couldn't get it running), cam chain adjustment set, all exhaust holes patched, rust cleaned out of gas tank with the electrolysis process (worked great!), petcock rebuilt/cleaned/polished, replaced fuses/cleaned fuse box & have been charging the battery every other day (hope it has enough to start it up).

So, does it sound like I got most everything covered for a fire up?

I am DEFINITELY going to do a valve adjustment as I'm certain it needs it. With 29,000+ miles I hope it didn't ruin anything.

Again, I just want to hear it fire up and at least run rough before I dump the money into it that needs to be dumped to make it road worthy (valve shims/valve shim tool, tires, rear brakes, front brake line, YICS tool & such)

 

Pretty much. Have you run a compression test yet? Might want to do that first, just in case. It would be a good idea to at least be sure all 4 cylinders can do their basic function before trying to fire it.

You can also CHECK the valve clearances with nothing more than a feeler gauge. Yes, the tool is preferred for re-shimming, but you can at least check clearances. If you've got a dead-tight valve or two, it could keep it from running.

If you get wonky compression test results, checking valve clearances will be the next step. I'd do it first myself.

 

I can do a compression test. My feeler gauges got rusty, I don't trust them giving me a correct reading with the surface rust. I need to get new ones. + donuts & probably a valve cover starts running me up in parts again (before I even know the shape of the engine). I understand the extreme importance of proper vacuum & valve clearances with cv carbs so valves will not go undone. Just gotta tool up first.

Compression test should yield more info. If my battery is weak will that scew my #'s?

 

You don't need donuts and a valve cover gasket if you're not planning on actually riding the bike; it's not gonna leak that bad.

The valve clearances are important to more than just vacuum for the carbs-- they can throw off your compression test results, as can a weak or low battery.

Go ahead and run a compression test; but if you get seriously low numbers on a couple of cylinders, then check the valves before jumping to conclusions. (I would still check the valves first to avoid possible consternation if you get uneven results, but that's me.)

A new set of metric feeler gauges, like K-D Tools' 2274, runs less than $10.

I've gotta add "my feeler gauges are rusty" to the ever-growing list of excuses I've heard for not checking valve clearances. At least it's not as bad as "a fat disgruntled old guy told me they'd be ok."

 

Now my curiosity has been piqued......with everything you did to the carbs, why did you stop shy of taking that last two steps and doing the fuel rail o-rings and the throttle shaft seals? Geez Louise.........now you're gonna have to take everything apart AGAIN. Hmmmmmm.....that sounds like a lot of US who have taken them apart too many times LOL

Dave F