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SP1 front shocks bottoming out after fork seal replacement.

3K views 8 replies 5 participants last post by  Johnny34 
#1 ·
Like the title says, my RC has been a great bike, but I am getting sick of the little niggling maintenance issues. I just got the left fork seal replaced, because it was leaking, and now the suspension is bottoming out, with everything on the same adjustment. SO I raised the preload and put everything stiffer, and it still bottoms out while hard braking and if I hit any sort of a bump. It did bottom out sometimes very slightly before the fork seal change.

So, question: did I do something wrong, or are the springs toast? I am 255 lbs with gear, and maybe I am just too big for this thing?

Is there a common mistake in doing the fork seals that might make the bike bottom out? any help appreciated. 2000 Sp1, about 20K miles, wrecked many times, basically a stunt bike.
 
#2 ·
DId you verify bottoming out with zip tie on the fork or is this what you are feeling thru the bars? If it’s actually blowing thru the fork travel I might suspect incorrect oil level. What fork oil are you using? Stock SP1 fork, valves and spring? Did you verify full range of rebound and compression settings after seal replaced?
 
#3 ·
thanks for gettine back to me.

I did not verify with a quick tie, but it is bottoming visually as you rock back and forth, standing with the front brake on.

I measured the oil volume i forget the exact number 514mL? something like that. It was the stock honda oil reccommended by the book. red oil, I forget the number honda ss8 10w.

Everything is stock, as far as I know. Everything on this bike was pieced together from ebay, and random places, ao I do not know the history of anything.

The range of settings (im not sure what you mean by that) but the adjusters work, and I have everything on almost full hard, and preload cranked way up. like 8 turns out.

I am pretty sure in feeling the fork tubes as they bottom out, the left one is bottoming, and I am pretty sure I did something wrong in changing the fork seal.
 
#4 ·
Your fork oil type and amount are correct per the manual. Did you bleed the cartridge after filling and check the oil level? Should be 135mm from top of outer tube. Reason I asked about zip tie is sometimes you will feel a shock thru the bars when the suspension doesn’t respond fast enough and might feel like it bottomed out. What are your sag numbers? That might give a clue as to what’s happening.
 
#5 ·
Thanks for everything. I am just going to take the shocks apart, and see what I did wrong. Something is not right, I can feel it, and the shocks are definitely bottoming hard, metal on metal.

I just like to ask a question to see if there is a common simple mistake I made, looks like there is not.
 
#6 ·
2000 SP1 is fixed!

I can have the fork leg off and rebuilt in about 15 minutes. I have done this three times, because each time I did something stupid, but I thought i'd post in case it helps someone.

First time, I did not seat the top slider in the fork properly, and that was causing the bottoming out. The top fork slider was sitting on top of the chrome fork tube within the gold exterior, and bottoming against the black rubber washer on the white top spring part (not sure about terms)

Then the next time, I was in a rush, slightly drunk and had a long day and FORGOT THE WASHER between the seal and the lower fork tube slider. What a dumba$$!!

No damage, just do it again. I destroyed the seal driving it in, when I took it apart, the little springs in the seal had been destroyed.

Fourth time, that was the charm.

If anyone is worried I am out there working on machines and ruining them, well, Im usually pretty good. Just effed everything up on this bike.
 
#9 ·
I can have the fork leg off and rebuilt in about 15 minutes. I have done this three times, because each time I did something stupid, but I thought i'd post in case it helps someone.

First time, I did not seat the top slider in the fork properly, and that was causing the bottoming out. The top fork slider was sitting on top of the chrome fork tube within the gold exterior, and bottoming against the black rubber washer on the white top spring part (not sure about terms)

Then the next time, I was in a rush, slightly drunk and had a long day and FORGOT THE WASHER between the seal and the lower fork tube slider. What a dumba$$!!

No damage, just do it again. I destroyed the seal driving it in, when I took it apart, the little springs in the seal had been destroyed.

Fourth time, that was the charm.

If anyone is worried I am out there working on machines and ruining them, well, Im usually pretty good. Just effed everything up on this bike.
Since you've got the fork assembly down you should consider swapping in some correct springs for your weight. Then again, if your just going for the sick whoolies who cares.
 
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