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Discussion Starter #1
I just bought a 2001 RC51 and on the ride home noticed that the front forks are leaking. Wondering how hard is it to change the seals and if anyone can help with how to do it. Thanks for any help and sure I will be asking more questions in the future.
 

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Take a look on youtube....there are quite a few videos that walk you through it.....if you don't think you can do it take it to the dealer.
 

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any update yellow00ltr i bought mine last saturday and i notices 3-5 droplets the next day after riding it, im not familiar with replacing fork seals, and one have any advice, and will the dealer rape me?
 

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If you don't have the tools, I'd take the forks to a reputable shop and have them do it.
It not difficult, IF you have the tools.
While your forks are apart for the seals, now would be a great time to check the status of the bushings for wear and replacement if needed.
 

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I rebuilt my forks this winter.
Like Sub said, it's no problem with the right tools. The Fork spring compressor, and fork seal driver are a must. I built my compressor myself, but ordered the seal driver from Motion Pro.
Bushings are inexpensive. I ordered seals and bushings from Ron Ayers.
 

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I rebuilt my forks this winter.
Like Sub said, it's no problem with the right tools. The Fork spring compressor, and fork seal driver are a must. I built my compressor myself, but ordered the seal driver from Motion Pro.
Bushings are inexpensive. I ordered seals and bushings from Ron Ayers.
Also replace the dust covers when replacing the seals.
The UV and ozone harden the rubber and they don't wipe the slider as well when they get old.
 

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Discussion Starter #13
You fill it from the top before you reassemble everything, fluid goes in before the spring and other parts do.
 

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Ordinarily, you unscrew the fork cap, compress the spring and the spacer, then remove the adjust case.
The decompress the spacer and remove the spring.
You can then use the holding tool on the cartridge along with a 10mm allen bit to loosen the centering bolt at the bottom.
The cartridge the comes out.

If you loosen the fork cap and then loosen the centering bolt, the entire cartridge/spring assembly will come out as a unit.
 

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sorry to threadjack but...... a friend of mine did my forks over the weekend with me slightly helping lol. one thing i have read since is that the preload adjustment needs to be backed all the way out before disassembly. pretty much all he did was take out bottom bolt, drain fluid, take off top cap, remove cartridge in one piece, replace seals and wipers, and reassemble with new fork oil. is it normal for the preload adjusters to be difficult to turn? (have adjuster knobs on them) did we mess something up?
 

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I believe you're referring to the SP2 forks with the black preload adjust nut?
They will have some resistance as you're compressing the spring, but they shouldn't be excessively hard to turn.
No more difficult to turn than the SP1 or any other fork.
Don't apply excessive force as you might round off either the preload adjust nut, or worse, the adjust case assembly.
Since that part of the fork wasn't disassembled from your message, were they always difficult to adjust?
 

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i never messed with them before the other day. i was given the adjustment knobs and stuck em on after we did the forks. i test rode it and while the front deff seemed stiffer, i am betting thats due to the 500ccs of fluid we put in. since it said 498 +\- 2.5 cc's btw.....its a sp2

would it have been possible to damage the internals having done it this way? or am i just being paranoid as usual?
 

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For the SP2, the preload adjust nut spins the adjust case, which is inserted into the adjusting plate. The adjusting plate rotates up and down the threads internal to the fork cap.

Here's a photo of the adjust case


And here's a photo the fork cap (upside down) showing the adjusting plate inside.


If the spring preload is very hard to adjust, the problem may center around the adjusting case movement.
Oil level would have no affect on this as oil level only comes into play as forks reach full compression.

The 489cc oil level for SP2 forks is with the oil lock piece in place.
If your forks are revalved, the company doing the work may remove the oil lock pieces.
In that case the oil level will need to be increased to prevent bottoming of the forks under heavy breaking.
The oil level in that case usually is around 120mm with springs out, or around 525cc.
 

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so would it have been possible to damage them without touching the black nut or messing the internals at all? literally we did the exact steps i posted earlier. the forks are stock as far as i know. if they were re valved then i was never told.
 
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