XJ700N rebuild brakes and forks

Hello Fellow XJers,

My xj700n has a very cloudy master cylinder glass and original rubber lines. It didn't break as strong as my xv250 when I first got it but the braking gradually improved after I had been riding for a while.

@chacal sent me the parts to rebuild the MC, both calipers, and replace the lines with braided steel. Actually @Toomanybikes ordered them for me when he was helping me with my carbs.

Both the seals on my forks blew so I ordered rebuild kits from Len and I put off doing the brakes. I didn't want to get the calipers all cleaned up while the forks were still puking oil. As it is the oil has been exhausted and there is nothing left to leak.

I have all the parts now so I am going to get started on Friday after work. (Or maybe take the day off work because I'd rather be working on the bike). I have to remove the calipers to get the forks off so I guess I will be doing both rebuilds in parallel.

Haynes and Clymer didn't make a manual for 85-86 so I'll try and follow along using the 80-82 Haynes manual I have. I am starting this thread so I can post pictures and ask questions as I go.

Thanks for reading.

 

Looking forward to check your pics. I just replaced my brake lines and pads. I bought ss braided 1/8. Nice project.
I will do my forks later; after seeing your pics! I am focus on my timing/valve clearance checks. once that I get her rolling; I will finesse it.
700X

 

So I took the day off work because life is short.

Here is a pic of my master cylinder glass that I will be replacing as part of my brake rebuild. I will feel better when I can see the level.

 

I will be taking the forks off to do the rebuild. I was just taking a look now and I see that there are little chrome caps covering (I assume) the bolt heads of the lower fork clamps.

Can anybody tell me the best way to remove these caps without damaging them?

 

Pry them off with a thin flat-blade screwdriver, edge of a razor knife, etc. They have a small "tit" on the backside that fits into the recess on the top of the socket head screw below it; it's just a friction fit.

 

OK, first challenge was jacking up the front end. I contemplated weighing down the back end but I think I would need a couple hundred pounds to do it so that is impractical.

The manuals say to use a jack under the engine block to get some blocks of wood under it but I would have to remove the exhaust to do that which isn't mentioned in the manual.

The trick seems to be in getting the blocks of wood under once you have it jacked up because there is only about 10 inches forward of the balance point.

Easiest way to do it would be to have somebody weigh down the back end and then push the blocks under.

Anyways, I got it up on blocks. Can you tell I've never done this before?

 

I found these engine removal frame bolts were loose. I wouldn't want the engine dropping out doing 160 down the Patbay Hiway.

 

Starting by removing the speedo cable as per the manual.

Loosened it with some needle nose players then spun it off by hand.

 

Taking the brake calipers off now. Started by loosening the two chrome bolts holding them to the fork. I'm also rebuilding the brakes so I also loosened the brake line bolt while it was still attached so I would have some leverage.

I screwed the bolts back into the caliper so I won't lose track of them.

Once the wheel is off I will be able to unfasten the fork reflectors and get the calipers out of the way.

 

Loosened the Axel pinch bolt on the right; there is no pinch bolt on the left because the Axel is threaded and screws into the left fork.

I am letting the calipers dangle on the lines because I am replacing the lines with new steel lines. If you are not replacing yours you will need to support the calipers so the lines are not damaged.

I found that the speedo cable will drop right out of the 'hose' if it is just left to hang so I will probably have to hook it back up to the gauge when I am done.

Axel pulled out by hand with a little effort and twisting so the wheel is now off.

It feels like the speedo hub will come right off the wheel now so I will put the wheel aside and try not to disturb it as I am not planning on touching the speedo hub today although it might be a good Idea to grease it while I have the wheel off.

 

Turns out you don't have to remove the fork reflectors to unfasten the brakes from the forks. They just hook on.

It's starting to rain now. That's odd because it never rains in Victoria!

 

Took the calipers off of the lines so I can drain the brake fluid. The are labeled left and right so you don't need to worry about mixing them up.

I put the line ends in empty water bottles because the manual said to pump the brakes to expelled the fluid. This didn't actually work and no fluid was expelled. Could be because the line is open in two places.

This is concerning as that fluid is going to have to come out at some point and it would have been better if it was controlled.

I will remove the fender before I do anything else with the brakes so I don't get any fluid on the paint.

 

Four bolts and the fender slides right off. Bolts back in place so I'm not looking for them later.

 

OK, so I think I read somewhere that it is a good idea to loosen the damper rod securing bolt at the bottom of the forks while the forks are still clamped.

I tried to do this (8mm Allen) but the outer fork tube just spins without the fender (which includes the fork brace).

I put the fender back on and was able to loosen the left side but I think the damper rod is just spinning in the right. I will probably end up improvising Yamaha special tools YM-01326 and YM-1365 which are used in the manual instructions.

 

I removed the chrome caps on the lower fork clamps using a razor knife as Len suggested. They came off easily enough but I do t this k it is possible to remove these without causing some level of damage to the caps because the metal is so soft. Probably won't be noticeable once they are reinstalled. I wonder if @chacal sells replacements at XJForever. Wouldn't hurt to order some when ordering the fork seals, etc..

 

Removing the cap bolt covers. Chrome cover over a rubber seal. Looks like a little bit of water got in there and caused some rust.

Manual says to loosen the upper fork pinch bolts before using the Yamaha Special tool YM-01104 to remove the cap bolt. Hmmm.

 

We don't want to remove that cap bolt yet. Just loosen it while the fork is still held by the lower clamp.

Yamaha Special tool YM-01104 appears to be a 5/8th Allen. Maybe (or more likely) a 16mm Allen. I don't have anything near that large. Looks like I'm off to the store to see what I can find. I'll get some penetrating oil while I'm at it considering the rust.

 

Yes, he does!

HCP4957 OEM bolt head DECORATIVE CHROME CAP, this push-in chrome-plated cap (“cover”) fits into the socket head of the bolt, and makes for a nice pretty finished appearance. For the following models: Use 2 per side (4 total) on all XJ700 and XJ750-X models for the lower steering under-bracket fork tube cinch bolts, use 2 per side (4 total) for the handlebar riser clamps on all XJ700 and XJ750-X models, and 2 per side (4 total) for the optional tall backrest pad retaining bolts on all XJ700 and XJ750-X models. Each

 

OK, so Yamaha Special tool YM-01104 is a 17mm Allen. Don't bother looking at Crappy Tire. You need a proper tool store to find one of these.

Cap bolts broke loose easily enough with the right tool.

 

Loosened the lower pinch bolts and the fork dropped right out.

 

With the forks off the bikes look a little bit like Cthulhu.

 

I suspect that getting the forks off was the easy part. Now I have to disassemble them without the aide of the Yamaha damper tools.

Here are the contents of the rebuild kit that Len sent me.

I think the washer and piston rings are part of the brake and lever parts I ordered at the same time.

 

The fork cap bolt can out easily as it had been loosened already. The kit includes a replacement for the rubber o-ring around the cap. When the bolt is u screwed the spring does pop the spacer out but not too violently.

This is where it gets messy so you should have a container to catch the fork oil and some rags. If you tip the top of the fork into a container the spacer, followed by the spring seat, and then the spring itself will fall out along with all the fork oil. The spring is about 2 feet long.

 

There is also a drain screw at the bottom of the fork. The manual doesn't mention it but the kit includes replacements for both the screw and gasket.

 

I don't know what is supposed to hold the chrome dust cover on but mine were bouncing around loose for awhile and slide right off.

The dust seal (or fork seal) came loose with some gentle prying. The fork seals are included in the kit.

 

Looks like I was mistaken. The dust seal and the fork seal are not the same piece. The dust seal covers the oil seal clip which holds the oil seal in. The oil seal is included in the rebuild kit but I did not receive replacement dust seals.

The clip comes out easily enough with a long narrow flathead screwdriver and needle nose players if you use the screw driver to loosen it up on all sides first.

 

The manual wants the oil seal to come out next but I don't see a way to do this without prying it out and risking damaging the surface it needs to seal against. I will skip it for now.

The trick is to get the dampening rod out first. I was lucky that I was able to break one of the dampening rod bolts on the bottom of the fork loose while it was still clamped. This allowed me to remove the dampening rod without using the Yamaha Special tool.



With the dampening rod removed I was able to use the inner tube as a slide hammer to get the oil seal out.



Looking at the head of the dampening rod I can now see what I need to reverse engineer the Yamaha Special tool. Looks like I will need a large Allen (maybe 22mm) on a 22 inch extension. Then I will be able to break the other side. This will have to wait for tomorrow.

 

I was mistaken when I said that earlier.

There are two washers there that belong on the dampener bolts on the bottom of the forks.

The 'piston rings' that I thought might be for the brakes are actually for the dampening rods.

It all starts to make sense once you get them all apart and can see how everything goes together.

What a great day. I can't wait until I'm retired and I can do this everyday. @Toomanybikes

 

Yep!

Good job on the right-up and images, thanks for documenting this!

 

^^^
I agree, nice write up. But boy is your wife gonna be pissed when she sees the fork oil stains on the carpet!

 

Yes thanks for the pics and a well documented job. With the mess that happened with "P bucket" this is great to have back on the forum.

 

Back at it this morning.

I was unable to locate a 22mm Allen socket for the dampening rod head. I thought of making a tool out of a piece of threaded rod and a 22mm but bit I could not find the materials. I have a sparkplug socket that has a 22mm hex on the top but it is not invertible. I couldn't find one to buy that was invertible either so I bought a length of 1/2" aluminum tube, flattened the end with a hammer then wedged it into the business end of the sparkplug socket. It too a few tries to get it wedged in tight enough but I was eventually able to break that dampening rod bolt.

It would be cheap and easy to order a proper 22mm Allen head socket off the web so I would recommend that you do that and be prepared rather than try to improvise a tool in the middle of the job.

 

Everything is apart now and looks in fairly good condition (bedsides the oil seals) so I will spend some time cleaning up the forks before I start the reassembly.

I'll be happy when the bike is resting back on 2 wheels.

 

Everything cleaned up to my satisfaction. Polished the inner tubes to remove a tiny bit of rust left by the clamps. Paid particular attention to the top of the inner forks where the dust and oil seals seat. Used some degreaser to break down the hardened fork oil and a bent paper clip to clean out the oil seal clip groove.

Replaced the cap o-rings and damper piston rings.

I will start the reassembly now.

 

First pop the tapered spindle into the bottom of the inner tube narrow end first.


Put the damper spring on the damper rod then slide the damper rod into the top of the inner tube so that the damper rod seats in the tapered spindle. You may need to shake it around a bit to get it into the spindle.

Slide the inner tube I to the outer tube and then fasten the damper bolt into the end. You should use some lock tight on the BT to make sure it stays put. Use the damper tool to hold the damper rod still and tighten up the bolt.

 

Slide the guide bushing and oil seal washer onto the inner tube followed by the oil seal. I lubed up the seal and bushing with some fork oil to make seating them easier in the next step.

 

To seat the bushing and oil seal I used a 1 1/4 abs coupling and a length of 1 1/2 abs pipe as per the advice I found searching XJBikes. The post suggested PVC pipe but PVC is not widely available here so I used ABS. The material isn't really important but it is important that the coupling is able to fit in the oil seal seat. My coupling was very snug so I used a hacksaw to cut a slice out of it so it would fit nicely.

Place the coupling on the oil seal then use the length of pipe as a slide hammer to seat the oil seal.



Drive the seal down until it is past the clip grove then install the clip. Make sure the clip is able to sit properly in the grove because it is the only thing keeping the oil seal in when you hit a pothole doing 80km on a back road.

 

Once the clip is in place you can put the dust seal back on. The coupling can be used to get it seated easily.

 

Drop the spent into the inner tube with the tight coils at the top then place the spring seat on the spring followed by the spacer.



Pull the inner tube out as far as it will go and then fill the tube with the specified amount of oil. For the xj700n this is 8.6 oz of 10w fork oil.

 

Once the oil is in the tube you can put the cap bolt on the end of the spacer and push down with your hand against the spring and twist to get the thread started.

Then you can tighten it up with your 19mm Allen.

 

I cleaned out the clamps then slid the fork up until the top of the tube is flush with the top of the upper clamp.

I guess the rest of the installation is fairly straight forward so I won't detail it all here.

I still need to continue with the brake rebuild though.

 

Oops! Looks like it is 13 oz of fork oil for the xj700n, not 8.6 oz as I said earlier. I was looking at the wrong model.

Good thing I caught this before I put everything back together!

 

Brilliant!
So question for you or someone who might know...
Is there a difference between your XJ700 forks and those from an XJ650?

P.S> love the hack with the aluminum rod!

 

Looking at the Haynes manual I can see that the fork cap is held in using a circlip on the 650 and 650R instead of the threaded cap bolt on the 700. The cap on the 650 also has an air valve. The rest looks very similar. The 750 and 750R forks are quite different with their adjusters and anti-dive units.