Complete XJ650 Rebuild

Here is a crappy picture of where it goes (circled), hopefully that helps (Note that the engine is upside down in the picture).

 

It just slides into place. The tabs the fit into slots, and the clutch cover secures the oil baffle.

 

Gnat, your picture is upside down!

 

Ha ha, the picture is actually right side up, the engine is upside down, or maybe I was just sideways when taking it! Funny thing is, that is how I took it, but when I saved it to mark it up, it was rotated so that the engine was right side up, but when I uploaded it here, it is now back to "upside down"

 

Excellent, that helps big time.

 

Here were my two questions after being able to ride it around for a bit yesterday.

1. I finally got the bike to idle pretty well on the center stand between I'd say 1200 and 1600 rpm. When I jump of the stand and ride around, shift through 1st, 2nd, 3rd, and just barely get into 4th. Everything runs smooth. But when I get back down to 1st and try to throttle a little it speeds up very slowly and when I switch into 2nd, it gets worse. But if I stop and sit a little bit, it gets slightly better.
It feels like it is not getting enough gas, like I have lowered the fuel levels in the bowls and they haven't caught up from accelerating through the gears the first time?
I moved my tank from run to prime and that seems to help sort of.
Could this be a fuel levels thing, need to adjust my floats? I used the clear tube to test the fuel heights but to be honest, it is tricky to make sure all 4 are right. Gonna check them again.

2. I can shift through gears easy but after I am in a gear, I get some heavy clunking. The noise is hard to explain but I can defiantly feel it in my feet and it is pretty unsettling sound. Almost like the clutch is catching very hard. Not sure if my above post with the oil baffle is part of it or not.
I messed with the tightness of the clutch and it didn't seem to make much difference. It is also very hard to get into neutral while it is running. As soon as I shut the bike off, neutral is a breeze.
Not sure is something is sticking or off?


Looking to see if anyone has answers or heard of these problems. As always, anything helps!!!

 

Got it out again tonight and messed with the clutch. I actually think the clutch is alright but here is a video of me walking it back to my garage. The bike is off and in neutral.
(The video will not load from my phone)
I will try and find another way but where the rubber boot is that is between the swing arm and the back of the engine, you can hear the clicking in there. As I Walked it back to my garage, it would catch and stop me from moving while in neutral.

 

You need to load all videos and photos to a hosting site and embed/link.

Sounds to me like you have a u-joint that has failed. Peel the gator back and have a look at it. WIth the bike on the center stand and the trans in neutral you can spin the rear tire and watch the u-joint. There should be no slop in the cross-joint. If there is any then it will need to be replaced. Yamaha didn't make them easily rebuildable.

 

Got any tips on getting that gator off easily? That thing was a B to get off and on the first time.
I will have to take a look at it this week.

 

It just peels off. Warm it with a hair dryer to make it a bit more stretchy.

 

<iframe src="https://player.vimeo.com/video/176257527" width="640" height="1138" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
<p><a href="">Untitled</a> from <a href="https://vimeo.com/user54773176">Devin Zdanciewicz</a> on <a href="https://vimeo.com">Vimeo</a>.</p>

 

not sure it that worked and sorry for the shakeyness. hard to film and move the bike. at about 13-20 seconds you can see it catch and shake the whole engine. Every other time I moved forward and stopped was because it was catching, not me braking or anything.

 

Can you confirm that you really are in neutral? Try starting it without pulling in the clutch.

 

As far as I know, yes that is neutral. 1. My N light is on and 2. That is the only time I can roll the bike with it turned off. If I pushed hard enough to roll past that click it will roll freely for a bit and then catch again. It is completely random when it clicks. When I was moving while the bike was on in 1st or 2nd, you could hear it clicking like that sparadically.
I do not have the relay connected to start the bike only in neutral. So as long as I have the clutch pulled in, it will start. I had to by pass it for now. I know it is dumb to not have that safety connected. Not sure if that is what you are referring too.
Also not sure if this has anything to do with what is currently happening. But when the bike is on the center stand and in N. If I was to spin the back wheel by hand, you can hear that click happen slightly. Something it catching but I am not sure what. I know this is vauge, I am just trying to locate the possible problem before I pull everything apart.

 

OK. That pretty well seals the deal. U-joint failure.

Unless......have you lowered the rear suspension?

 

Nevermind. I looked back and see stock shocks on it.

Peel back the gator. I'm fairly certain that you'll find a sloppy U-joint.

 

So I think I found out what my problem was

These are 3 of the 4 bolts that connect the u-joint to the engine... F me

The 4th is yet to be found but sounds like it is in the swing are itself.

No idea what happened to it or how it came loose. Need to take apart the whole swing arm and check the damage.

 

Umm......crap. That's not supposed to happen. Someone had that apart before; the bolts are normally somewhat difficult to break loose.

 

Yea was not happy to find that but at the same time, glad I could find the problem that quickly and have it be that blatant.
2 bolts were off, one unfound so far, one laying inside the gator. The 3rd came off with a little pressure and the 4th was pretty difficult to get off.
Like I said, gonna take the swing arm off and check everything out, hopefully nothing bad.
When I go and put it all back together with new bolts was thinking about adding thread lock to them?
Is there any reason why I shouldn't?

Hopefully after this I can be back to riding around and doing final adjustments.

 

They should definately have thread-locking compound on them. Medium strength.

In terms of cost, be very happy that the problem was loose bolts and not a failed u-joint. Getting a good used one can be tricky, and new costs $$$.

 

Good news! No damage (outside of the bolts getting chewed up)
Replaced them today and added loctite.
Took it out for a little roll around and things seemed to be very smooth so hopefully that problem is in the past.

Next question, which was looked over before.
I start the bike and it idles between 1200-1500 rpm. Can get into 1st, 2nd, 3rd pretty good. When I slow down and drop back to 1st it is almost impossible to get it into neutral. Just skips right over it. On top of that when I come to a stop it revs up to 2500-3000 rpm.
Eventually I will try moving again and try and get through gears but now it is struggling.

In my mind I think my bowls have not filled up with gas, also my like I have "used up" what's in there and the tank can fill fast enough. Not sure if that is even a thing.

I am running air pods and have changed my main fuel jet to 120's and pilots to 41's. I aslso have PVC tubes in the pods to help control the air flow direction. I know pods are always a debate on here but the PVC had got me the closest to controlling idle. I feel like this is not about the pods but more about the carbs, etc.

I am not worried about proformance, etc. right now. Just looking to ride.

Any ideas or suggestions?

 

Took my first ride around today! Very pleasing feeling after almost 2 years of this rebuild.

Couple things I was hoping to see if anyone had suggestions on to help me feel more comfortable on this.

1. After riding for a while, I get white smoke coming out of my shifter case. Pouring out. I have a little pod filter on there because I have no air box. Not sure if that is normal or something I need to correct.

2. 2nd gear is kind of a SOB and it was this way when I bought bike 2 years ago. My friend rode it and said there was a problem. Not knowing, I tore the whole engine apart and found my 2nd fork snapped. So I want to figure out what that is before I snap this one. 1st and 3rd, 4th, 5th... All very smooth no catching. But 2nd will catch accelerating and when I am trying to pull out of a rolling stop from 2nd, very catching, jumpy.
I have read a lot about different oils, etc.
Along with this I have a very minor oil leak. Maybe .5 oz. a day, again coming from the shifter case (not sure if that is the right name)

3. Finally, bike will not start cold at all. Need to use starter fluid. Then when I have it somewhat warm. One push and it starts everytime, no choke needed.

 

1. Oil mist. Get a length of oil line and run it yp along the frame so the filter is tucked in out of the rain. The mist will collect in the hose and run back down into the sump.

2. Sounds like the dogs on #2 may be worn. Did you replace the alternator chain guide when you had the cases split?

3. What is the idle set at when the engine is fully hot? You need to find a middle ground between full hot idle and just warm idle, or you'll have cold-starting problems. Don't trust the tachometer to be completely accurate about what the idle speed really is. The idle when fully hot will be a bit higher than when just warm.

 

1. Can do. Does the length matter or just far enough to tuck away?

2. Yes I replaced the chain guide. The large black "plastic" (not sure if it is or not) piece that bolts in, yes. Hopefully it isn't something else I missed. I have just read a lot about slipping wet clutchs and then grabbing hard, so that is in my head everytime it catches:/

3. After my ride, I had a great idle at 1050-1150, sounded very good. But the engine was pretty hot. At just warm, 1200 and up seems to be where I need to keep it before it wants to die, then after it gets warmer, I can get closer to 1100. Still sounds a little fast at just warm but again I messed around with my carbs and jets. So I imagine things are gonna be slightly different.
Could I be too rich at cold start? 41 pilot jets right now... Not sure if that could be it.
I color tuned it pretty warm twice this weekend and feel good about it but after how the bike sounded after the ride today and the idle after. Makes me want to try it again.

 

1. Just long enough to tuck away, but longer is better than shorter so the oil doesn't soak the filter.

2. Good deal. Try a smooth-firm shift. It may just be your technique not playing well with a 30 year old machine.

3.
I have the hot idle on my 750 set to around 1200 RPM and it starts well when cold. Every bike will be a bit different for a great number of reasons, all having to due with wear as the engine gets used, so play around with your idle speed until you find that happy medium.
If it starts on ether then you aren't too rich when cold.

 

Got some good and bad news about this project.
Crashed the bike on a turn the first couple days out:/ That's the bad news.
Good news is I'm ok (outside of some scratches and two broken bones in my hand) and the bike still runs outside of a completely ruined headlight (looking for a replacement. mainly the ring and blub, my bucket might be ok), bent exhaust mufflers, bent handlebars, and a clicking/rubbing in my swing arm which seems to be just past the U-joint.
Back to wrenching so I can get out again maybe in a few weeks

Oh yea, wear a helmet if you don't. That is the only thing I remember about my crash and they are worth every dollar.

 

Wow that's too bad about your bike but glad you're ok!

 

Hope you have a speedy recovery, and that the hand issue isn't too disruptive.

 

Back to fixing some stuff on the bike after the crash now they gave me the go ahead to move my fingers;/

Looked at all the damage and everyting is good but have some sound coming from my swingarm, a rubbing sound when I spin the back tire.
I thought that possibly the U-joint got slightly bent and was barely touching the inside of the swing arm, so I replace the U-joint and inspected the drive shaft. All looks good and the sound is still there.
So I am wondering if the Middle Gear (the part that sticks out of the back of the end of the engine, not sure if that is the right term) is bent slightly?

Attached is a video of the sound, you can't see, but the engine wiggles back and forth when it rubs.

 

Pull the wheel.
Look and liaten as you spin the drive splines.
Pull the final drive.
Look and listen as you spin the drive shaft.
Pull the driveshaft.
Check for straightness.
Basically pull a part off and see if the sound goes away. Repeat until you find the culprit.

My guess.... the tire is rubbing. The question is why.

 

Hey guys, been a while.
Got the bike back on the road last night for the first time in almost 2 months! Felt pretty good

My hand seems to be back to normal and think I repaired all the problems on the bike. Leaking a little Oil which took a new gasket. Got a new headlight which was damaged in the crash. New handle bars. And while in the process upgraded to a Mac 4 into 1 exhaust.

Finally got it started last night which sounded pretty good overall. Had a little problem getting it started, had been siting for a little bit.

Question and this was happening before the crash.
I can not get it to start with out spraying some starting fluid in the carbs. Once it fires up things seem to run fine. Before the crash if I shut the bike off it would start up fine (being that it was warmed up) but a cold start never happened.

Last night once I had it running I took a little spin around the neighborhood, overall it seemed to idle pretty well at 1100-1200 RPM but at that moment I realized my choke was on the whole ride. Once I shut the bike off and turned the choke off, it wouldn't start again.

Am I running Rich or Lean, where to I start to get this thing to start cold?

 

I'd start by looking at the plugs. Are they a tan-brown color? If not, you have some adjusting to do.
Not starting, even with choke on, leads me to think the enrichment circuit(s) are gummed up or blocked. I will say, I find how much choke I use depends on outdoor temp. Too much or too little and it won't fire.

 

I checked one last night and I would say slightly black, dusty.

 

I ended up finding out that 4 bolts that held my U-joint to the Middle gear output shaft, I had put new bolts on there and they were maybe 2 cm too long and were rubbing on the inside lip of the swing arm. Ground them down and no sound at all. Sometime so small...blow my mind really

Just need to get this thing to start without starting fluid and I am good to go

 

Devin,

There are those of us (ahem.....) that are affectionately known as 'Parts Hoarders"--- if you need parts, contact me ( ahem....I mean US), and I'll (cough cough,I mean WE'll) see what parts are laying around. It'll cost a whole lot less than Ebay!!!

Glad you're on the sunny side of the dirt.

Dave f

 

Considering it's getting cold, have you checked the status of your battery? If it's not too strong, you''ll turn the engine over just fine, but there's not enough juice to actually get a spark going.

As far as enricher---sounds like you have some clogged jets somewhere.......