front end

[Flying Scotsman]

12 mm.I just bought one for my forks.They are sweet now.I am going to rebuild the front forks on the 86 as well now I know how to do it.

[Arnie]

The internal hex socket is 27mm.   The head of a 3/4" bolt happens to be 27mm (1 1/8) so you can use that welded to a rod.
Check with Randy for a repair kit with seals, metals, and dust covers.

Arnie

While Im on the subject of front end my bike has gone eskimo and blown my fork seals. R/H one leaking pretty badly.... what size ( if anyone can help that is) is the hex to hold the damper rod while you undo the bottom bolt? is it a hex or a spline... due to time restrictions (need it for work) getting allllllll the stuff together before removal.
cheers in advance.
neil

[RichBaker]

I used a broom handle last time I did mine.... Just stick the end in the damper rod, put the other end on the floor and put pressure on the whole thing, while using a 10mm allen to break the damper bolt loose.

[oldktmdude]

  If you have access to an impact gun you can usually undo the retaining bolts without holding the damper rod. When re assembling, it helps to secure the damper rod just to make sure you have enough tension on the retaining bolt.  Regards, Pete.

[Kopfjaeger]

  Thank you! Got the 27 mm one sorted Arnie, and I have done the broom handle trick before but that was on a DT175, didn't know if the FJ was going to be more difficult. For the record there are very noticeable handling differences!!!! Thinking it would be a good idea to get hoses, seals and bearings, pads and brake seals and do it alllll at once.
thanks again
neil

[Kopfjaeger]

OK. After being with flu for a week and ordering the parts on Tuesday, got the front forks done... just bumbling slowly through it... something about work being a timid animal... Got Pictures to show, RH fork was easy as to get out and undo, seal popped out no worries... as you will see the damping rod had a burr on the lower end where the retaining bolt goes into it, I dressed it back and cleaned and washed and reassembled. I found reassembly easy? and this concerns me as it surely cant be that easy. Once I had the fork leg apart I removed the upper from the triple clamps, removed seals, spacers,bushes etc, cleaned, reassembled, Used a bit of rubber grease to aid the seal on, slid the damping rod and spring through the fork leg upper, put the funky aluminium cap with its thrust washers in place, ( it states in the manual that i should have 2 other flat washers, but when i removed all this , all i got was 2 thrust washers....),line up notch in damping rod end to spigot in lower fork leg, slid fork leg upper into fork leg lower, insert Special tool No. 2  ( Broom handle). make sure damping rod is on spigot and tighten bolt into damping rod. Done. Still tinkering away, havn't decided wether to put Loctite on the damping rod retaining bolts or if a good clean and a run over with a die nut  and set to tension will do. Included in the pics are my front fork special tool.

High tide marks. part of my clunk was the horn bottoming out on the mud gaurd.



Undone.Hope you like my budget bike stand.



The culprit.



Bits



Damping rod burr. LH side was way worse almost all the way round.





SPECIAL TOOL!!!!!!!



Thanks for your advice fella's. Moving slowly onto my brakes now, got the new seal kits for them. Must be coffee time first but!!!

[RichBaker]

I've seen that burr before, it comes from NOT lining the locating notch up with the locating screw.....

[Kopfjaeger]

Yeah its funny hey? All the while I have been bitching about not having a rattlegun or an air compressor, I'm observing what happens (potentially) if you rush things and perhaps use BFI instead. still having trouble with LH fork, isnt seating right, don't want to pop the seal and check in there because I'm thinking it will destroy the seal, trying broom handle and wieght and see how we end up, have cleaned the thread and moved things round and felt things out. in no rush.

[Kopfjaeger]

Allright got it together. The LH damper rod didn't want to seat on its notch, on closer inspection ( and some bearing blue) established the tip of the stub had sheared off, so loctite on the bolt, got it seated and got to tension. Oil in forks, no leaks really firm, in a good way. Brakes still dragging, with the callipers off the wheel spins fairly freely, noticed that the LH side calliper inner piston was extended more than the outer. pumped the inner all the way out and cleaned it and then pumped the outer piston out and cleaned it and pumped it back in. With just the LH calliper on, the wheel has a little drag on it, but no where near as firm as it was, was unable to turn the wheel backwards with out major effort before, and now it feels like they are juuuuuust dragging a little bit, nowhere near as bad, did the same to the RH side, feels pretty good going to leave it now, been looking at it and tinkering away for two days on it now. Might go for a spin tommorrow, weather and enthusiasm ensuing.

One side out more than the other.



Pumping out Piston.




Dirty?



Clean!




Cheers.