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Main Area => General GS500 Discussion => Topic started by: rger8 on February 15, 2010, 06:48:04 PM

Title: Sucking oil out of forks?
Post by: rger8 on February 15, 2010, 06:48:04 PM
If I want to change my fork oil to 15 wt. cant I just suck it out of the forks with like a bulb sucker thingy ( technical term ). I want to put Sonic Springs in as well and don't want to take the forks off to do this.  I don't mind if a little 10 and 15 wt. get together.

Any real problems? :dunno_white:

PS: Does anyone know if the sonic springs they sell for the GS 500 come in the stock length?

Thanks!
Title: Re: Sucking oil out of forks?
Post by: gsJack on February 15, 2010, 07:44:51 PM
I overfilled my left fork tube after installing a new seal last spring and had it all put back together so I just removed some oil the old fashion way.  Took a piece of tubing and with the outer end below the oil level I sucked by mouth to start the siphon action and it flowed out slow but steady after started.  It was a small diameter piece of unused battery vent tubing I used.

Don't know about Sonic springs, I have Progressives.
Title: Re: Sucking oil out of forks?
Post by: the mole on February 15, 2010, 08:37:27 PM
Taking the forks off is really easy and quick to do (15 min), you can get the gunk out of the forks and do a good job.
Title: Re: Sucking oil out of forks?
Post by: jrains89 on February 16, 2010, 01:20:54 AM
take a 4 foot piece of vacuum tube or gasoline tube, duct tape to the end of a shop vac hose, put all the way down to bottom of fork, turn on shop vac, wait 30 seconds. this was my technique. had the old crap out and 20wt in in less than 5 minutes.
Title: Re: Sucking oil out of forks?
Post by: galahs on February 16, 2010, 05:03:41 AM
Read this thread about fitting Sonic Springs

http://gstwins.com/gsboard/index.php?topic=24872.0
Title: Re: Sucking oil out of forks?
Post by: dauphinc on February 16, 2010, 06:09:11 AM
When y'all changed the oil in the forks, did you have to get the load off the front forks (lift them into the air)? Also, I weigh 125 pounds. Would 20w oil be too much?
Title: Re: Sucking oil out of forks?
Post by: RichDesmond on February 16, 2010, 08:03:14 AM
Quote from: rger8 on February 15, 2010, 06:48:04 PM
If I want to change my fork oil to 15 wt. cant I just suck it out of the forks with like a bulb sucker thingy ( technical term ). I want to put Sonic Springs in as well and don't want to take the forks off to do this.  I don't mind if a little 10 and 15 wt. get together.

Any real problems? :dunno_white:

PS: Does anyone know if the sonic springs they sell for the GS 500 come in the stock length?

Thanks!

It's really much better to pull the tubes off the bike, and it's actually a very easy job. If you can remove and replace the front wheel you can take the tubes off.
You'll never get all the old oil out with the suction method, and the bit you leave in is the dirtiest, nastiest part.
The springs are a different length than stock. This is for a few reasons, both technical and business. With a better rate you don't need as much static preload, so the total spring/spacer length has to be shorter with the new springs. So even if our springs were the same length as stock you would need to cut the spacer.
Title: Re: Sucking oil out of forks?
Post by: RichDesmond on February 16, 2010, 08:07:33 AM
Quote from: dauphinc on February 16, 2010, 06:09:11 AM
When y'all changed the oil in the forks, did you have to get the load off the front forks (lift them into the air)? Also, I weigh 125 pounds. Would 20w oil be too much?
Best way is with stands. A rear swingarm stand and a front stand that lifts from under the steering head. Lot's of other methods, if you have a garage with exposed rafters you can suspend the front of the bike fron them, using soft ties around the upper triple and rachet straps to hoist the bike.
20w is too much for the stock springs, use 15w.
Title: Re: Sucking oil out of forks?
Post by: DoD#i on February 16, 2010, 08:18:17 AM
It's not so much the mixing of 10 & 15W that's the issue, it's that you are not going to get the crap out of the bottom - the only way crap gets out of the forks is by changing the oil, short of disassembling them (which would effect a very through oil change). The oil you can't get to suck out in the bottom will be exactly the oil that's most loaded with metal particles.

Taking the forks off is trivial. It's worth doing. I also suggest using the excess fork oil (you have to buy a liter, but you only need something like 725ml ? Perhaps less?) to flush out the forks after you drain the old oil and before you add the new oil, rather than leaving a quarter bottle sitting on the shelf. Put some in, put the caps on, pump the fork, take the cap off, drain it out.

Dauphinc: 20W oil and you weigh 125 lbs? Way too much.

Yes, you have to prop up the front of the bike. Put on centerstand, tip back, drop a jackstand in place to catch the front crossmember. Takes about 5 seconds. If you don't, the bike will collapse when you take off the fork caps that hold the springs in. Beyond which, the forks need to be fully extended compressed when measuring the level of oil in the tubes upon refilling.
Title: Re: Sucking oil out of forks?
Post by: glynnd89 on February 16, 2010, 02:42:22 PM
Is there some sort technique to get the oil out? Because all I seem to follow is to turn them upside down and let them drain? Just a little confused in front suspension. I was looking into racetech springs but have never done anything with the front suspension before, and it kind of scares me.
Title: Re: Sucking oil out of forks?
Post by: DoD#i on February 16, 2010, 03:10:44 PM
Turn, drain, pump (move tube - rather easy with no spring in there) drain more. Arranging a way to hang the fork over the waste oil collection is convenient, as you then don't have to stand there.

Nothing to be scared of. Straightforward job.