New to the XJ world

Well i just got my first xj. It is a 1981 XJ550, that is about all I know of it. I'm not restoring the bike, just the motor. I don't know how it is going to work, but I plan to put the motor on my Johnny Pag Spyder. I just finished rebuilding the motor and a few minutes ago found out how to re-time it. So I hope soon to be posting pictures. When i'm done I will have several left over parts that are in pretty good shape. Is there anything else I might have to worry about with this motor?

 

** BUMP **

Left-over parts? That statement needs clarification.

The best course of action for you is to BUMP this Thread until you catch one of the 550 Boys willing to send you the Play-by-play for Timing the Engine.

Setting the Timing is done by following a precise order of instructions.
Each XJ Model varies slightly; but the basics are the same.

My advice to you is to acquire a Manual.
Nothing is better than having the most critical procedure detailed and illustrated when you need to do something like Re-Time the Plant.

 

The parts I was talking about is items such as both fenders, both wheels, forks....etc. I have it timed now and doing good except I'm getting no fire at all. I have been reading older forums on here trying everything talked about. As i was about to start re-checking the wiring harness, I discovered it had a kill switch on the kick stand. (This only being my second bike ever, I'm still learning) I followed that wire and discovered most of it had been cut off the bike. So tomorrow I will work on that and then check for fire.

 

OK! no more shade tree mechanics for me. I have been waiting for the manual to arrive in the mail. (I think I look a little crazy standing next to the mail box all excited like a young child) Anyways, I was told how to time the engine, well it was wrong. So it's been tough the last couple of days trying to figure out what I did wrong. BTW I copied and printed how to do it the proper way off one of the forums and will be doing it the RIGHT way tomorrow. But the good news is I completely figured out what was wrong with wiring and I'm happy to say I have power to everything. ( In case your wondering, I'm not trying to turn it over at all!) Only problem I for see right now, remember I'm only restoring the engine, is that I cant find the correct torque for the cam cap bolts and the sprockets. If anyone could help, it is greatly needed!!

 

Any progress on this... I like the look of the Johhny Pag spyder but always thought that a 200cc engine is just not big enough....
When you get the 550 in there that will really haul a$$...

 

Only update I have is that both motors are out, and just waiting on a gasket kit I ordered to come in. The wiring seems pretty much the same, and it will take very little fabrication for the motor mounts. I hope to have the engine finished, painted, and mounted by this weekend. Will have some pics up soon.

 

definetly wanting to see this project with pics.....this sounds unique. I like the pag bikes but 200cc is crap

 

That is the biggest reason I started this. It's a blast to ride. But the motor is made from the cheapest metal possible, and it's just a piece of junk. The frame is good and well made. Its just a horrible motor on it. A chopper shop did this with a cb750 and a 650. They have had an easy time doing it, of course they have way more time, tools, and know how than I do. But it is fun and i'm learning a lot.

 

Update..... The motor is on the frame, not on motor mounts till tomorrow. I went through the wiring today and hooked everything up. GOT FIRE!!!! So I figured out what was wrong before, the regulator wasn't working on the XJ frame. Got the pod filters in the mail today, brake light tomorrow, and hopefully the gaskets Monday. Painting it Wed., and hope to test ride by Fri. ( trying to post a pic, lets see if it works)

 

Maybe. Did you split the cases?

And I have another concern in regard to this whole idea: What rear wheel and sprocket are you using for this bike?

Does it have an internal drive cushion like the one on the XJ?

Have you done your math on the sprocket ratios?

I have a feeling this thing may work, but not for long. Seriously.

 

Did you start with a 500 Seca or Maxim? If it was a Seca, Do you have a good tank and side covers available for sale?

 

No I didn't split the cases. And i'm a little clueless to the internal drive cushion is. But I did have the sprockets taken care of.





And i'm using the motor of a XJ550 Maxim

 

If you take the rear wheel assembly that came off the Maxim and PULL the sprocket and hub out of the wheel you will find a series of rubber blocks that engage "paddles" on the hub (or vice-versa.) This "cush drive" is the shock cushion for the driveline. Virtually every real motorcycle has some sort of provision for this engineered into it.

Without any cushion in the driveline, the transmission, clutch, and in the case of the 550 Yamaha, primary chain and tensioner, will take one heck of a beating. As will the chain, and frame/suspension of the motorcycle.

I took a look at the Johnny Pag website; you're putting a motor from a 400+ pound motorcycle into the frame of a bike that was designed for half of that. The XJ550 motor makes just about double the HP of the anemic little 300cc twin whatzis that JPM designed their "bikes" around, with TONS more torque, and the ability to generate WAY more speed than the rest of the chassis was ever designed for.

While this thing might work, I'm concerned that all you are building here is a recipe for disaster. If it does work, it's gonna shred itself in relatively short order, and hopefully NOT you in the process.

I honestly feel this project needs a re-think, before you hurt yourself. Sorry.

 

My chopper has a rear wheel set up pretty close to what you described. and to let you know the Maxim is 407 lbs (185 kg) and the Spyder is 360 lbs (163.3 kg). So I don't believe 47 lbs is going to make that much of a problem considering the frame is rated for 360 lbs with up to an additional 300 lb person riding it. I have also seen and spoken to people who have done this with bigger motors then what i'm using. And they have been almost daily used for more than a year each. I'm not using this for drag racing or trying to show off speed or take off. I am not that type of rider. I always have a gentle take off and get to a good cruising speed and leave it there. but I will use the extra torque to get out of the way if needed. I would much rather have a twisted frame instead of being hit. I understand the possible need for other modifications and what-not in the future. But i believe, and will continue too, that this will all be worth it to me.