Fork tube jammed

Very little, till I got it into my head to fit some hyperpro springs.
All was going well till one of the forks locked down necessitating strip. The culprit seems to be the oil lock (an innocuous looking little sod), but a strip that far means a new oil seal - these have been ordered and I have been driven to string drink.
It's a sad and sordid tale...

I had that lockdown issue. On one occasion I managed to 'pull' the top half free but twice I had to dismantle the forks again. Some kind of vacuum forming in there?

Déjá - vu

I also had the same problem while fitting my Hyperpros the other week after setting the oil level on the fork. Managed to pull it back down after clamping it back into the head stock after much cussing.
The same happened on one of my burgman forks on a rebuild last year........

Be safe, be seen!

steve_h80 wrote:

(Snip) The culprit seems to be the oil lock (an innocuous looking little sod)(Snip)

Oil lock? Steve, what’s an oil lock?

Cosmic_Jumper wrote:

steve_h80 wrote:

(Snip) The culprit seems to be the oil lock (an innocuous looking little sod)(Snip)

Oil lock? Steve, what’s an oil lock?

Item 11
https://www.fowlersparts.co.uk/parts/4896162/fjs600a6-2006-e-abs-mph/front-fork
For some reason the oil lock jambs itself solid in the bottom of the fork tube, which is what causes all the hassle trying to rextend the fork.
I think know a way to unlock it insitu using judicious violence but that's a last resort.
I didn't have this hassle last time I changed the fork oil...

Does one of the admins want to split this thread or change the title?* It's gone off topic and is setting off my OCD

*Done. Thanks for the suggestion.

Thanks for that.
The fork rebuild I now on hold pending delivery of parts: fork seals, oil stop, seal driver, a new box of matches...

It's frustrating, so I had to make sure that the top half of the fork didn't make solid contact with the bottom half while I was rebuilding. Naturally, I grew an extra pair of hands to accomplish it.

It's something to note mentally for future reference...and step away from the matches!

I've been researching.
The oil stop getting stuck thing seems to be a common problem and just the nature of the beastie. I found a couple of good leads on the Web explaining what the oil stop is all about and a U-tube of some guy cussing at a Suzuki Bandit fork - same design and the same problem.
Anyway the postman has delivered the fork oils seals and the oil-seal-basher-innerer so sometime later in the week I will head into the shed and start the rebuild.
Expect swearing.

I didn't quite get the science behind it but it felt like a suction vacuum being formed between the oil lock and the fork top-half when it bottoms out. I was able to release it by brute force on only one occasion.

I've already got my ears covered for the forthcoming swearing.

I wonder if a judicious cleaning of the fork tube would go towards reducing that tendency. Back in the day I was advised to add a healthy quantity of mineral oil after emptying the fork tube of fork oil. Then pump the tube up & down several times and empty the mineral oil. Do this until the mineral oil came out clean. Then thoroughly drain the tube and proceed with the fork oil procedure.

Anyway just a thought.

I did notice an awful lot of Gunk sitting in the bottom of the lower fork so I completely de-greased the inside and made it shiny new again. It took about 4 attempts to shift it.

Well that's the forks reassembled.
I just  managed a short test ride up the road before more snow sent me scampering for home, the forks do feel more planted though although a longer rode is needed to make a real assessment.
The oil lock did stick the tube down again during the rebuild, but now I have a suitable broom handle that fits down the top tube, hold the top tube, tap the top of broom handle with a mallet and it frees off. There isn't any vacuum involved, just friction.
Apparently the oil locks function is to rapidly increase the damping force as the forks approach full compression, whatever it doesn't jamb with oil and springs in place.
So that is the good news