Another new aussie

Hi all I have been a keen observer of this great site for a few months now reading through the forums and collecting heaps of great info on the way. I have 2 XJs a 1981 750 registered on road done 42000km just needs some TLC and a 1980 650 which Im in the process of rebuilding. It was in good going condition when I got it about 5 years ago but the motor has not been started in that time. Ive been busy doing up the frame, brakes etc and are now turning to the motor. Have just cleaned and bench synch the carbs and now wonder if I should pull the heads, check valves etc while the the motors out of the frame. Would appreciate your ideas.

Cheers Brian

 

Hi Brian,
Talk about a life-saver! This site I mean
As far as pulling the head and checking the valves etc and my experience with maintenance on the XJ goes... It seems to be a given that if you think something might need attention is probably needed attention a looong time ago, on my XJ at any rate.
But, I would check the valve shim clearances and then the compression before pulling the head since you may just be the lucky one!
Good Luck!

 

Thanks cds

At first that was all I was going to do, clean carbs and check valve clearances until a mate sugested that while the motors out pull the head a give the valves a bit of a grind. I guess if all the cylinders have similar compression it should be OK

Cheers

 

I had one cylinder, number 2, which appeared to have been overheating like crazy since number two header had a lot of the chrome burnt of it and the actual cam cover was/is yellowed above the cylinder's position.

After checking the shims it became clear that this cylinder(number two) was completely out of whack compared to the other three and when I pulled the head(I had an oil leak and was replacing the cam chain... maintenance!) and lapped in the valves, number two needed a whole lot of extra time and effort so...

I'm not sure if that's helpful but just a thought if you notice something odd between the cylinders it may be worth digging a little deeper while the engine is out...

Mind you, once you've pulled that motor out a couple of times I'm sure it will be like second nature!

 

Trying to eliminate how many times I do that! Ill take it one step at a time and see what pans out and thanks for your help.
Brian

 

Hello brianw2 and welcome.. See how you go with th comp' test wet and dry then take it from there, as cds said. Spose it depends on how much you intend on using th bike as to how much you put into it in th first place.And to what degree you enjoy / or not th hands on side of having a bike, I get th impression you like that part too.

Heres to good numbers on th test.

 

Hi Bushy

Yeh love tinkering away in the garage not a mechanic by any means but learning really fast with the help of this site. If I can get the time will do commpression test this weekend Let you know results. By the way were is Somers

 

South of Melb'.......aintcha got google?

 

Hello Brian. There are a few of us from Victoria. I have fond memories of the '81 XJ750. A mate used to have one, which was the first big(ish) bike I rode - about 15 years ago now.

 

Hi railtrolley
I reackon that Victoria must be the capital of XJs when I was looking around for a parts bike for my XJ 650 75% of them were in Victoria. I got lucky in the end and found on on my back door step 2kms from home the only trouble was that I had to buy his Xj 750 as well he wouldnt part with just one of them. Collection just seems to be getting bigger!! Ive got a 4 car garage lucky to get 2 car in at the moment! Any way having a lot of fun Its been 30 odd years since being on a bike slowly getting some confidence back

Cheers brian

 

Just done Compression test not so good they went
115,115,110,130 Dry
120,125,120,135 Wet
looks like a top end job coming up