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Maromero
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Discussion Starter · #1 ·
Yesterday I held my breath and took the plunge, I took my bike to the bikeshop and disassembled the "empty" leg of the Spinner, chopped 1 cm off both bumpers, top and low, changed the oil to 2.5 and set the pressure to 80 psi.
I haven't got a chance to test it, I'll do it tomorrow and will post first impressions after modifications, the only thing I know by this time is that the distance between stanchions and crown is 7 mm more than before.
Anyway, thanks to Slobdog, Nino and D8 for pushing me with their impressive posts.
 

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uhhh...

i wouldn't want my fork to become any longer!
that way you slacken the headangle. i would have cut only the bumber which prohibits the fork from bottoming. you also cut the top-out bumber so it moves farther out. we will see how that affects overall travel.

the change to thinner 2,5 oil alone works miracles!
 

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Maromero
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Discussion Starter · #3 ·
nino said:
i wouldn't want my fork to become any longer!
that way you slacken the headangle. i would have cut only the bumber which prohibits the fork from bottoming. you also cut the top-out bumber so it moves farther out. we will see how that affects overall travel.

the change to thinner 2,5 oil alone works miracles!
Well, let's see how it works. Anyway I wanted to increase the lenght a little, so let's see.
 

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Doesntplaywellwithmorons!
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7mm of increased length is NOT going to slacken the angles much. We're talking a third of a degree. You have to be majorly anal to worry about a third of a degree.
 

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bi-winning
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DeeEight said:
7mm of increased length is NOT going to slacken the angles much. We're talking a third of a degree. You have to be majorly anal to worry about a third of a degree.
i agree. "that is going to slacken the head angle" is a popular response on mtbr. Yes it will, but 7mm! come on. not a big deal.
 

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Doesntplaywellwithmorons!
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The most commonly quoted rule of thumb is 1" = 1 degree although a single issue of MBA once put it more precisely as 0.71" = 1 degree on a 42" wheelbase bike. That at least puts something else into the equation... on a longer wheelbase bike, raising the headtube 1" will have less effect than on a shorter wheelbase bike. Then there's the fact that because the fork is on an angle, increasing the length by 1" doesn't actually raise the front end height by 1".
 

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Doesntplaywellwithmorons!
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Then there's SAG... the 7mm increase was measured without him sitting on the bike I bet. So assuming a standard XC racer 20% sag rate... he's only increasing the sag height by 5.6mm ?!
 

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Maromero
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Discussion Starter · #9 ·
Well, tested today on a long climb with some technical parts, descending on dirt road + some technical singletrack.
Couldn't feel a lot of difference in the angle, but there is more travel, also there is some brakepad rubbing that wasn't there before, anyway it feels more plush, good or bad, I like it.
As a bonus, I lost 4 gr.
 

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I think you did the right thing. I would've cut the top out bumper a little in hindsight on my own fork. The brake pad rub is a little concerning. You can also still safely take another 5-7mm off the bottom out bumper. Check my old post for how much I slashed off - it was a little over 20mm iirc but right at the limit of what would otherwise create contact with the tire and arch.

How much 2.5w did you put in? @ everybody How do people accurately add oil, subtract oil and measure the distance to the top of the stanchion? I always found it a little awkward. I used an empty pen sheath to add small amounts of oil and then a narrow piece of paper to measure the depth while also watching the oil with a flash light. I could make a crease in the paper against the lip of the stanchion when it just touched the oil and then I could measure it. However all of this was a little awkward and "ghetto" i.e. not very professional seemingly.

I look forward to hearing how your fork performs as well as comparisons to other forks you have ridden. I keep running with lower psi to get a little more active fork. So far I think I would like to run oil around 60-55 but I'm not sure if this is best. I'm 196lbs.

The bolt on my right leg seems to be stripped because it isn't tightening anymore or loosening and come off. But the fork still works and the bolt is stuck in. ???
 

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Maromero
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Discussion Starter · #11 ·
The oil wasn't measured this time, I just poured in until it reached 4.5 cm from top, don't ask me why. Last time if I recall I used 145 cc of 2.5/5 w, but I couldn't notice any difference.
Compared to the SID's I had, this one is still more stiff even after the modifications, even considering the brakepad rub.
 

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doccoraje said:
The oil wasn't measured this time, I just poured in until it reached 4.5 cm from top, don't ask me why. Last time if I recall I used 145 cc of 2.5/5 w, but I couldn't notice any difference.
Compared to the SID's I had, this one is still more stiff even after the modifications, even considering the brakepad rub.
the further out the stanchinos are the flexier the fork gets since you have less overlap.
45mm is too much oil! lower that to 60mm and try again with the same pressure. also important to move the fork up and down after adding the oil to help any trapped air come out. as mentioned in the other thread i already get 73mm of travel without cutting any bumpers. no brakerub on my fork. maybe you should use some steel-bolt on axle in the front. this usually helps fighting flex.
 

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nino said:
the further out the stanchinos are the flexier the fork gets since you have less overlap.
45mm is too much oil! lower that to 60mm and try again with the same pressure. as mentioned in the other thread i already get 73mm of travel without cutting any bumpers. no brakerub on my fork. maybe you should use some steel-bolt on axle in the front. this usually helps fighting flex.
That's true - if you are using a ti skewer a steel one might help. I also found my tune hubs to be flexier than my Extralights! (however the overall 32 spoke tune wheel is probably stiffer and stronger)

Nino your fork must have been different than mine. My fork PHYSICALLY could not travel beyond 57 or so mm. At 55mm I was pushing into a very stiff bumper. I couldn't tell then when the fork was bottoming out really because, like doc says, it's such a stiff fork. TBH I can't really tell now when or if my fork bottoms. Travel coming from the bumper (beyond 55mm on my fork) could not have had very good shock absorbing characteristics. Mad Kocks also trimmed his Ares too in order to get a more reasonable amount of travel. I don't know what spinner was producing!?
 

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What does the fork weight?

What was the claimed travel of the fork before your modifications? I see that you are now getting 73mm of travel and I'm wondering how the fork tracks. Do you find stiffness to be an issue?
 

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Maromero
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Discussion Starter · #15 ·
MajorPain said:
What does the fork weight?

What was the claimed travel of the fork before your modifications? I see that you are now getting 73mm of travel and I'm wondering how the fork tracks. Do you find stiffness to be an issue?
Claimed travel is 80 mm. Tracking is pretty similar to what I had before, at least I can't feel a dif, the same can be said about stiffness.
Weight 1268 gr, minus 4.1 gr on bumpers;)
 

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Maromero
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Discussion Starter · #18 ·
updating

I just got back from a 2 day ride, 28 k ascent to a Biosphere Reserve to spend the night at 2100 m and 80 k of descent? (cumulated ascent first day 1650m, second day 1450m) to sea level.
First of all, the brake pad rubbing dissapeared, it happens that one brake pad was much closer to the rim and I didn't notice, after adjusting, voila, no more rubbing.
The fork is working great even without taking off some of the extra oil. The spul valve is active and the rebound is quicker than it was before. After some technical singletrack, rock gardens and dirtroads, the travel I got was 69 mm and stifness is still great.
I think the extra travel obtained is worth taking the risk.:thumbsup:
 
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