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Old 07-13-2010, 07:41 AM   #19111
Bbasso
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"air gap" What's that?

I'm pretty sure that changing the oil won't be enough... I am really pushing the limits of the suspension :p
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Old 07-13-2010, 07:57 AM   #19112
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Quote:
Originally Posted by Bbasso
"air gap" What's that?

I'm pretty sure that changing the oil won't be enough... I am really pushing the limits of the suspension :p

Well then just freekin STOP IT then..






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Old 07-13-2010, 08:10 AM   #19113
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Air Gap

The Air Gap is the measurement from the top of the oil to the top of the fork leg with the spring removed and the leg compressed. The lower the measurement the more oil in the fork = stiffer action. More measurement = softer/less oil.
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Old 07-13-2010, 09:11 AM   #19114
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Quote:
Originally Posted by kenny61
Ill give it a try. The PO has the top nipple (pic1) and the round thing on the side (pic 2) plugged. Ill hook em together today and see how it works.
Coming home last night it stayed low the entire trip....
Hooked em together. No difference
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Old 07-13-2010, 09:46 AM   #19115
Bbasso
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oh... thanks.
But do you really think adding/subtracting oil will prevent bottoming out?
Honestly, I am pushing the bike a lot harder then in past. The only thing the bike is doing that I don't like is bottoming out, The rest of the suspension's setting are right on point and give me confidence.

Never mind the rear suspension :p
It's also bottoming out but way less then the front..
Just checked, no leaks from the forks.
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Old 07-13-2010, 10:13 AM   #19116
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Bottoming Out

Get some PVC tubing and make a spacer 1"-1.5" and preload the fork springs.
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Old 07-13-2010, 10:22 AM   #19117
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Quote:
Originally Posted by Bbasso
oh... thanks.
But do you really think adding/subtracting oil will prevent bottoming out?
yes I do.

Some old guy named Pascal discovered that you can't compress a liquid but you can compress a gas.
Your forks have both a liquid (oil) and a gas (air) inside them. As the forks compress, the oil is forced through a valve to slow down the fork movement and the air pressure goes up and acts as a secondary spring.

If you are to add more oil, this means there is less air, so the air pressure rises faster, the forks feel stiffer.

You measure this amount of air by measuring how high the fork oil comes up inside the fork tube. The lower the measurement number, the higher the oil level, which means there is less air in the forks.

Also going with a thicker oil will slow down the speed at which the fork can compress. This can also help you from bottoming out.

You can also change to a heaver rate fork spring.
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Old 07-13-2010, 10:32 AM   #19118
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Yes

Quote:
Originally Posted by Bbasso
oh... thanks.
But do you really think adding/subtracting oil will prevent bottoming out?
Honestly, I am pushing the bike a lot harder then in past. The only thing the bike is doing that I don't like is bottoming out, The rest of the suspension's setting are right on point and give me confidence.

Never mind the rear suspension :p
It's also bottoming out but way less then the front..
Just checked, no leaks from the forks.
Raising the oil level in the forks will reduce bottoming out. It does have its limits though. I felt that the front was softer then the rear. Like you I bottomed the front more then the rear. I went with stiffer springs in the forks and raised the oil level. I also went with slightly heavy oil since there is no rebound damping adjustment.

Increasing preload on the forks will have no effect on bottoming. At full compression the spring rate is unchanged by preload. If you were to shorten the spring and fill the space cut off the spring with a spacer it would stiffen the suspension.

If your bike is under-sprung there is no fix that will give preformance as good as going to heavier springs.

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Old 07-13-2010, 10:42 AM   #19119
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Compression Damping

Quote:
Originally Posted by towpro
Also going with a thicker oil will slow down the speed at which the fork can compress. This can also help you from bottoming out.
There is compression damping adjustment that would do the same thing. If you do this to try and prevent bottoming it will cause several other unwanted suspension/handling problems. I found this out the hard way by trying it. You won't like.

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Old 07-13-2010, 10:50 AM   #19120
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Quote:
Originally Posted by Bbasso
oh... thanks.
But do you really think adding/subtracting oil will prevent bottoming out?
Honestly, I am pushing the bike a lot harder then in past. The only thing the bike is doing that I don't like is bottoming out, The rest of the suspension's setting are right on point and give me confidence.

Never mind the rear suspension :p
It's also bottoming out but way less then the front..
Just checked, no leaks from the forks.
Sounds like you are very close to what you want. 20 oz 10 weight each leg on forks & crank up shock preload a slight bit & enjoy.
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Old 07-13-2010, 04:05 PM   #19121
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Quote:
Originally Posted by Bbasso
oh... thanks.
But do you really think adding/subtracting oil will prevent bottoming out?
Honestly, I am pushing the bike a lot harder then in past. The only thing the bike is doing that I don't like is bottoming out, The rest of the suspension's setting are right on point and give me confidence.

Never mind the rear suspension :p
It's also bottoming out but way less then the front..
Just checked, no leaks from the forks.
You could also try adding between 2 and 6 psi air pressure to the forks, this has the same net effect as raising the oil level. I know a lot of folks don't recommend this but the forks are designed for this ability. I would take all the above advice and try each recommendation, in series or parallel and experiment with the appropriate settings, i.e. compression clicks, oil level, spring pre-load shims and a small amount of air pressure. This will eventually get you a stable platform you can hammer on.

One other thing to note, the springs only hold the bike up with you on and determined the sag, in theory you only need stiffer springs if there is too much sag. You need the correct front sag to get the full 11 inches of travel, overly stiff springs are just as harsh as too thick an oil, too much air pressure or the compression clicks turn up too high. HTH
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Old 07-13-2010, 04:24 PM   #19122
Ben99r1
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Exhaust thread and bolts.

I removed my header last week to get ceramic coated. While I was taking out the exhaust I broke a threaded stud. I was able to have it removed and installed a new. What I need advice is what is the best way to clean the rust on exhaust threaded studs? Thanks Ben
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Old 07-13-2010, 05:15 PM   #19123
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Quote:
Originally Posted by Ben99r1
I removed my header last week to get ceramic coated. While I was taking out the exhaust I broke a threaded stud. I was able to have it removed and installed a new. What I need advice is what is the best way to clean the rust on exhaust threaded studs? Thanks Ben
California and rust? I didn't know those two went together......
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Old 07-13-2010, 05:21 PM   #19124
mchester
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Quote:
Originally Posted by flatfender
You could also try adding between 2 and 6 psi air pressure to the forks, this has the same net effect as raising the oil level. ...HTH
I know before I revalved my forks, I found addign a couple PSI to the forks was a VERY small change. Oil level or weight is a much more significant change.
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Old 07-13-2010, 05:29 PM   #19125
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Quote:
Originally Posted by flatfender
California and rust? I didn't know those two went together......
I bought the bike with 18,000 miles and 11 years old. The guy I got it from use to keep it two blocks from the ocean. Ben
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