1985 xj700X Maxim X 1st valve adjustment

Well I have owned this bike many years, not original, but since 90. Anyway its up for its first valve adjustment this winter. Is it hard to fine the shims (pads) for this bike? Where is a good place to get them? Looks like a challenge. Any info would be appreciated.

Thanks

 

Sorry, no idea on availability. Only thing I can see is that your bike uses the bucket over shim setup like that used on Kawasaki's, rather than shim over bucket of other XJ's.

This means that you'll need to pull the cams if any shims need to be changed. The shims look pretty small from the parts diagram... maybe the same 9.5mm as used on newer Kawasakis?

Please take and post some pictures once you've got the valve cover off. I would really like to see what that cam and valve setup looks like!

Thanks,
Paul

 

Chacal stocks them, unless I miss my guess. Last I knew he only had OEM as opposed to aftermarket, but it's worth a shot.

 

The adjustment shims (called pads on the X) are easily available from Chacal, Zanottimotor.com, or there is a pad pool run by HAP on Maxim-x.com.

The pads are under the bucket so the camshafts have to be remove to replace the pads. With 20 valves the job requires a high level of organisation and care.

 

Hi cr7198,

to do a valve adjustment is fairly easy. If you follow bigfitzs' instructions. You don't have to take any cam apart. It is on AIRHEAD VALVE ADJUSTMENT

http://www.xjbikes.com/Forums/viewtopic ... valve.html

All you have to do is just a search and there it is with pictures, step by step instructions.

 

I'd just like to remind you that the title of this message thread says "Maxim X". The X is watercooled, and the shims are mounted under the bucket, rather than on top. If he needs to change any shims, then the camshafts are going to have to come out.

 

I did this on my X this summer. Scariest thing for me was taking the cams out (actually the scary part was getting them back in correctly).

I'd recommend the shim pool from HAP. See this link

Other tips (I realize you didn't ask):
- I replaced the valve cover gasket and rubber washers at the same time.

- Pulling the lifter buckets up was kind of tricky, the oil seals them and they resist being pulled out. Some pulled out with fingers, others I *gently* used a crescent wrench to 'pinch' them on opposite sides and pull them up. It didn't appear to leave any marks. I was barely using any force, certainly wouldn't want to use vise grips or something with a knurled face.

- The manual said to remove all the locating pins between the cap caps and the head, but some were pretty tight. I think I left a couple in. Some came out with the same wrench trick.

- Tightening the bolt on the cam chain sprockets was tough... hard to lock down the cam and keep it from moving while you're torquing the bolt on the sprocket. I had a 19 or 21-mm open-end wrench that I ground down so it would fit better. This was still tricky. I cheated a little and used a wrench on the timing plate under the left side cover. This is bad because it applies torque through the cam chain, but not as much torque as the bolt sees because the chain is farther out from the axis of rotation; you get a leverage effect. I'd actually like to hear some other suggestions from people who have done this.

- The instructions for the cam chain tensioner from the service manual were good. When removing it, you want to loosen the end cap bolt first, otherwise it's hard to apply leverage when it's off the bike. I put a new gasket on between the tensioner body and the engine - when I reinstalled the tensioner body, the gasket slipped down on one side, so only one bolt went through the gasket... this caused a leak that took me a while to figure out.

 

I'll chime in with a couple tips:
To get the buckets out of the head, I used a valve lapping drive. (a suction cup on a wood handle). Slipped them right out.

The shims usually "stick" to the inside of the bucket when you pull them up due to the precise finish and film of oil. DO NOT drop one down the engine!

Leave the plugs in the holes (see comment about dropping stuff into the engine)

I removed one drive screw on each camshaft gear and then rotated it 180 degrees and then remove the other two. THEN use wire ties to secure the chain to the gear so you don't need to worry about the timing. Mark the direction of the cam on the gear before you spin it.
I also wired the chain up on the front and back so it didn't skip a cog on the crankshaft.
Once the screws were out I slid a 5/16" threaded rod through the center of the camshaft and tightened nuts down on each side to make it easy to spin the camshaft without turning over the engine. Once the rod was tight, I could turn it by cranking the nuts (trying to tighten them)

You need a NARROW feeler gauge set to get into the intake valves. About 3/8" wide will fit. The set will need to go down to .0015" or .002"

HAP's shim pool is great but it will take a little time to send the shims back and forth so don't expect to get them back in a day.
Some of us have a bunch of spares on the shelf so start a thread when you figure out what you need and we'll check our stash.

Go slow, plug the camchain slot with rags and don't drop anything.
Do NOT overtorque the camshaft caps or you will be bumming!

 

thanks for all the great info everyone. I have done valve adj. on other bikes, but this one makes me a bit neeeeeeervous.
OH, the other question......valve cover gaskets? I see that places like bike bandit do not carry them anymore. I haven't checked my local dealer. Any other place?

 

I replaced my valve cover from the dealer, they still have them.

Mike, I have to bring you down here to help me with my valve adjustment. It sounds like you had an easier time than I did wtih mine...

 

1. It is VERY important to measure and document the existing gaps carefully - double check them as they form the basis for recalculating the new pad size. You will find that the gaps are very small or non existant with some valves.

2. There is a downloadable Excel spreadsheet (see maxim-x.com) which calculates the minimum number of pad sizes needed to get them all into spec, by redistributing the existing pad sizes in the most efficient way.

3. I used a magnetic pickup to lift the bucket off the valve, do them one at a time and write down the pad size. Make sure you put the bucket back (minus the pad) on the same valve. Then move onto the next valve.

It is not a difficult job just take the time to do it carefully and methodically.

I have done 4 maxim Xs with no problems yet anyway.

 

I'd love to come down, but the family and work have me tied down tight.

The first one I did was on the bench after I lapped the valves (learned a lot with that one)
The last one I did in the frame and, you won't believe me....but I didn't even pull the carbs! Don't ask me how I got the tensioner off or more amazing how I got it back on and tightened down. You gotta love those whobble head extensions.

I cut a standard set of feeler gauges down and curved the ends to follow the lobe better. The right tools and good workspace help a lot.
It doesn't hurt that I just had the whole bike completely apart 4 months earlier. I was kicking myself for not touching the engine when it was out!

 

how often do these adjustments need to be done? I know its about every three thousand on airheads....