XJ750 Engine removal and split - Pictures.

Definitely not!
Oh and I bought most of these parts ages ago... so it doesn't count!

 

cds - this is an awesome pictorial. So helpful! And your comments that go along with the pics are worth - well - they're priceless when you consider the time they may save another xj'er in the future.

 

And I bet you still believe in Santa Claus ;o)

 

You can make a Jig to hold the Pistons all-level at the half-stroke to make inserting the pistons back into the cylinders less of a chore.

Here's the Idea.
The measurements differ bike to bike.

http://books.google.com/books?id=x_qLnB ... ig&f=false

 

Mirco - You know looking through the pictures has made me stop and check things that I just wouldn't have seen originally. It's amazing how the camera captures so much more than you see while you're working on it.

Wiz - I started keeping a tally and freaked myself out and stopped. I now keep an eye out for bargains or swaps and also realise that it is a passion more than a necessity. Doesn't Santa claus sell cocaine infused tonics?

Rick - Excellent info! Thanks!

 

50. Clean barrel to case gasket face on barrels and fit jug o-rings and oil dowel o-rings.
51. Check barrel to head gasket face and re-face if gouged.(check with steel ruler across face.)
52. Put rear chain guide in before putting the barrels on. (the guide will wiggle through the chain hole in the barrels, after they are on, but tightening the chain guide retainer properly is difficult with the barrels in place.)
53. lower the 2 centre pistons onto the piston holding jigs.(I made these with an extra hole that the front of the piston would sit in. good thing to stop them slipping out when dropping the piston but bad thing to get out because you have to raise the piston a lot more than without the hole to slide them back out.)
54. Align the rings properly on each piston. No ring gaps above each other or facing the ports.(follow the manual for specifics)
55. Slop oil all over the pistons and barrels then lower the barrels gently onto the two pistons. Push and squeeze the rings into the piston ring grooves to allow the barrels to edge down slowly. Work on both the pistons equally to keep the barrels level with the case face. (Can't do this with gloves on. If the ring won't push into the ring groove, because its wedged, then tap the barrels upward with one hand and squeeze it in again. Take your time and be careful as it won't require any extra downward pressure to accomplish.)
56. Align the two outer pistons and do the same. (raising the 2 centre pistons and then removing the jig and putting it under the 2 outer pistons would be ideal but it seemed a bit too hectic to mess around with the jigs and the piston heights at this point so I put the outer two pistons in with patience and a few retrys to get them straight into the bores).
57. Tap the barrels down, evenly, onto the case face and oil channel dowels and tighten the front stud nut.(keep it level front to back and watch the front stud that it heads into the case hole properly.)

 

58. Fit Head and torque.(keep an eye on those YICS o-rings when lowering the head)
59. Fit front cam chain tensioner.(Make sure it is located correctly at the bottom of the case... use a torch)
60. Fit cams, fit tensioner, setup, fit cover.

 

Very nice CDS, thanks

just a quick question, was the chain(s) starting to rattle or just a precautionary maintenance replacement ?

 

Hi OzRoad,

The starter chain was making a slapping/knocking noise at idle which annoyed the hell out of me and I thought it was going to be a lot more stretched than it was.

The cam chain I have replaced previously because of the top end rattling/clicking it was causing.

The having to take off like riding a 125cc was what prompted the piston/barrel upgrade... plus darkfibre bought a big bore kit and I got his first purchase(the barrels and pistons) at a good price!

I had a lot of fun doing this... although those oil channel head stud bolts feel too springy for my liking!

 

I like this thread and all the pictures you took (that I forgot to) when dismantling the engine.
Gotta go with the idea to re-split the cases, which I have to do as well.
It's a pain in the butt, but you gotts to do whats you gotts to dos...

 

I know what you mean.
It was no where near the chore I thought it would be to tell the truth because the gasket was very easy to get off the 2nd time around, since it probably wasn't actually cured, thankfully!

The engine is all back together and in the bike now, so it's time to get the colourtune plug and carbtune out and make this thing purr!

I still feel nervous about the way those 2 oil channel head studs feel when you torque them up... I think it must be the copper washers or something that makes it feel like they spring back when you take the pressure off and it's probably the reason i stretched the hell out of them the first time I did the head gasket and had to replace the studs on this motor. Well that and I didn't use a torque wrench that time around... just my 'i think it will take more' sense of feel.

 

Just a Final followup -
I have put just over 200Km on the motor since re-installation and I now remember what a 750cc ought to feel like to ride.

It was well worth the time and effort.

sidenote: Oh and that springy feel on the oil channel studs must be normal... cause they ain't leaking, Thankfully!

 

Pr0n!

 

Hey CDS, can I ask you how the rods felt when you torqued them up to 18,1? Mine start to stick around 7,2 already...

 

Hi Erman,
Sorry I'm not sure what you mean by rods and the 18,1 and 7,2 have got me stumped also.

I didn't separate the piston rods from the crank, if that's what you mean though.

 

That was exactly what I meant. Thanks for the reply =)

 

mmm looking good<a href="http://s1291.photobucket.com/user/c...esktop - TONYS-PC/my xj750/IMG_16781.jpg.html" target="_blank"><img src="http://i1291.photobucket.com/albums...ket Desktop - TONYS-PC/my xj750/IMG_16781.jpg" border="0" alt=" photo IMG_16781.jpg"/></a>

 

Is there any chance someone has these photos downloaded and is willing to repost them?! Would love to see what I'm getting into next weekend.

 

I see the photos just fine. Try again, maybe there was a server bug on the hosting site.


EDIT: The photo hosting site is indeed beig slow. I had to reload the first page twice to see all of the photos.

 

Do I have to remove head an cans to split the case?