FF: Forks Girdraulic eccentric shimming method

[Albervin]

I cannot see how you can install more than 20 balls easily. I have used 19 balls for decades. Now I have managed to fit my fork blades and that was a day job. First of all there was a very small burr on a spindle that I didn't see so it would not enter the blade or the bush. Fixed that with a fine file after a little bit of cursing. Then with just some light oil I attempted to assemble the fork blades. Initially there was swearing! I was only using a light plastic mallet but I couldn't square up the links. Then I just raised and lowered the links a few times and all fell into place. I am now in this situation where there is a slight (40 thou) variation in the full extension of the forks (no damper and no springs). Not sure if this is acceptable so some input please.

 

[greg brillus]

Actually the bike with the extra ball, was some other chap who rebuilt the bike himself........2 possible items there for you Alyn, Ok first it looks like your lower spindle is the wrong one.......it should be the one with the short 7/16" thread, so only a single thin nut on there only..........Second item which might explain the clearance issue, it looks like the eccentrics are not in the correct spot against the trail stops, thus if they are out of alignment that will cause the difference in spacing.

 

[timetraveller]

I'm not sure that I understand the question. The photograph shows more of a gap between the fork blades and the eccentrics on one side compared with the other. Is that the 40 thou? With the way that I set up JE front ends it is the damper which limits the travel, both up and down so it the problem is that in principal the forks could move more on one side than the other before hitting the eccentrics then once the damper is installed that should not come into it. If I have not understood properly then sorry but give some more details.

 

[Albervin]

Actually the bike with the extra ball, was some other chap who rebuilt the bike himself........2 possible items there for you Alyn, Ok first it looks like your lower spindle is the wrong one.......it should be the one with the short 7/16" thread, so only a single thin nut on there only..........Second item which might explain the clearance issue, it looks like the eccentrics are not in the correct spot against the trail stops, thus if they are out of alignment that will cause the difference in spacing.

Greg, the drawings clearly show the FF14 X 2 spindles. Upper and lower links. They also show 2x 570 nuts for upper and lower links. The trail stops are dead centre for left and right.

 

[Albervin]

I'm not sure that I understand the question. The photograph shows more of a gap between the fork blades and the eccentrics on one side compared with the other. Is that the 40 thou? With the way that I set up JE front ends it is the damper which limits the travel, both up and down so it the problem is that in principal the forks could move more on one side than the other before hitting the eccentrics then once the damper is installed that should not come into it. If I have not understood properly then sorry but give some more details.

TT. This is the extreme range of the forks with no damper or springs attached. Of course it will not reach this extreme once the limits of the springs and damper is attached. I was just curious as to whether the alignment may be awry. I do like to rebuild my Vincents only once as it leads to more road time and less shed time later.

 

[Bill Thomas]

Is it just more meat on one leg ?.

 

[timetraveller]

OK, my guess is that you will be alright but I would just check with a Vernier the diagonal distance across the eccentrics and the fore and aft width of the fork legs. Bill's suggestion of different fork legs might be right Are they both original or is one a modern milled from solid item? If the diagonals across the eccentrics are the same and if the fork legs are the same then there is something else which needs to be investigated.
Greg is correct regarding only one nut on the spindle for the eccentrics. The reason for two on the rest is to allow adjustment for the clearance to allow the dust covers to rotate. The spindle through the eccentric has to be fully tightened and does not need a lock nut. I think that if you look at the old original drawing again you will see that it is easy to confuse the front and rear spindles.

 

[Bill Thomas]

Looks like one .

 

[Albervin]

TT. Yes, I misunderstood Greg. The eccentrics were rebuilt by Ken Phelps so I have to assume the job is correct. There appears to be more metal on one side of the top link, looks like it has been like that forever. With one blade now fitted the links move smoothly throughout the range of movement. I will fit the other blade today and that should prove whether or not all is well. I will then disassemble and grease everything before final fit. Thanks for the input from everyone. Sometimes reading the books is not enough.