Let the PO bashing begin...(forks)

Tonight I started the tear down of the forks. No rust on the inners, so that's great. Got one out, torn down to where it's time to remove the damper rod bolt. This is where the PO comment begins: The 6mm hex fitting is boogered. Not bad, but enough you can tell someone's tried and failed before. So, I thought I'd try using my impact screwdriver (it works with sockets too). Tapped the allen head socket down nice and tight, attached the impact driver and started in with a 12oz hammer. After a couple nice whacks it's turned 1/4 turn, so I pulled impact and used a ratchet. Very little force later and the wrenches fall out, revealing a nicely rounded hole where there should be a hex shaped hole. DANGNABIT!!!

It's soaking in more PB overnight, but I'm thinking it's going to require some heavy artillery to get that dang thing out. Anyone have a trick to get the oil seal out WITHOUT disassembling the damper rod bolt?

 

No.
Drill the "Allen Head" off the body of the Bolt.
That will let you extract the Damper with the body of the Headless Bolt still attached.

 

Good advice.

Proceed carefully, using ever-larger drill bits until the head comes off the bolt.

If the "stub" still doesn't want to come out, judicious application of heat will help.

 

Just to add a bit of a hint, you will see copper of the washer once you have gone through the bolt. You want to stop there pretty quickly!

 

Thanks guys. Looking like a rainy day here today, so I'll be doing some careful drilling today.

 

Just incase things go bad.... Some monthes ago I saw
a pair of polished xj forks go for between $60/75.
It was here or ebay.
They looked unbelievibly fine. If I had't just done mine I would
have snapped them up.
So deals are out there!
good luck.

 

Good luck on that fork job.

There was a thread some time ago called "Stupid PO Tricks" I think, and had some pretty amazing stuff in there. I started a list of my own encounters but it got too long and depressing.

 

Well the drilling is complete on one fork. It's actually pretty amazing how soft that bolt is! I have some Dewalt bits that the tip have a little section that helps locate/pre-drill for the bigger section. I just drilled down a small ways (Basically eyeballed what I thought was the depth of the head). Gave it a tap with pin punch and the head broke off. A 5/16" bit is just a hair smaller than the bolt shank size, so if someone reads this down the road don't go any larger than that.

I did figure out that I totally forgot the dust seals when I made my order from Len, so that'll be on the next round of parts. Now I need to do a search to verify that I've got the damper rod/ anti-dive parts laid out in the correct order/orientation. Pretty sure I can find the bolt I need at the local hardware store, so I'll get everything but the dust seals put back together.

 

Re: Finding the bolt at the local hardware.

Only maybe. Yamaha tends to use odd thread pitch fasteners compared to those commonly available, be careful.

 

Thanks for the warning. Actually that bolt is pretty standard. M8-125 x25 was a perfect fit. Of course, they don't have 'em in stainless, so for now it's just gonna be a placeholder. I also picked up some socket head cap screws for the carbs to replace the ones in the upper and lower mount brackets. ~$10 for everything. The smaller ones are M5-.80x10, the larger ones are M6-100x12.

I'll upload some pics here when I get a chance.

 

Some pics:

the offending bolt:


The solution, good Dewalt bits with the little pilot bit tips:


Just before a quick tap with the punch:


The result:

 

And my interpretation of the FSM's version of how things are arranged, (also, this the way they came apart:

From the left
Damper rod, flat washer, spring washer, valve, valve body, damper rod bolt. (the FSM uses different terms, but you get the idea)


Finally, the OE bolt. If someone sees this in the future it might help to know how much you need to drill out. The trick is GO S L O W L Y!

 

Nice piece of work!!!
Looks like you caught that Bolt ... right ... dead .... center!!!

Great Pictures!
People learn about what stuff looks like when you supply great accompanying images.

Looks like Nylon Slider Time.
Was it a fight getting the Bolt out of the Damper?

 

Thanks Rick. Those drill bits made all the difference. re: nylon slider, why do you say that? Maybe you're seeing something I missed. I hope not.

The bolt just unscrewed with finger pressure. My guess is the head was just frozen enough to the lower tube that it wouldn't move. I was ready to go at the threaded portion with vice grips but it was very easy with just fingers.