GStwin.com GS500 Message Forum

Main Area => Meet and Greet => Australian Meet & Greet Area => Topic started by: brembo on September 18, 2006, 02:17:49 AM

Title: Fork springs.
Post by: brembo on September 18, 2006, 02:17:49 AM
My GS is up for some new front pads (when the shop gets them in), so while the front end is getting worked on I might as well get some new fork springs put in. Now I know a few of you guys have the Sonic springs in, just wondering what they're like, what spring rate you've got, your weight, and what sort of riding you do (commute, sporty, agressive)? The mechanic suggested either .85 or .9, but I'd like to see what you guys think from first hand experience.

:cheers:
Title: Re: Fork springs.
Post by: bubba zanetti on September 18, 2006, 04:58:54 AM
I've got the .80 (I think, could be .85) racetechs in mine. I mostly do commuting, riding aggresivly when ever I can. I havent had a chance to do any touring yet.

I'm more than happy with them, but I also did the rear shock at the same time. I picked up approx 15 - 20 k's/hr through a bend.

BTW I weigh about 85kg give or take. I also have Pirelli sports demons on the bike. I've only done about 500k's since doing the suspension & still have to sort it out properly.
Title: Re: Fork springs.
Post by: galahs on September 18, 2006, 09:32:02 PM
I got 0.85kg/mm Sonic Springs for my 2005 GS500F. I weigh 75kg's and they are the perfect match for touring and handling. If I was going to do more track work I'd go harder like 0.95 - 1.00's.

Best upgrade ever! and got them sent straight from the USA, got them in 5 days!!!  :thumb:
Title: Re: Fork springs.
Post by: brembo on September 22, 2006, 03:58:01 AM
Put in an order for .9's from sonic springs tonight, should have them in a week or two  :cheers:
Title: Re: Fork springs.
Post by: brembo on September 26, 2006, 02:57:34 PM
Well that was quick, they just turned up then. 5 days for US->me :D
Title: Re: Fork springs.
Post by: galahs on September 26, 2006, 07:40:29 PM
Yeah it suprised me too. Sonic have their international shipment down patt!


Now stop talking and put em in!  :thumb:

Title: Re: Fork springs.
Post by: brembo on September 27, 2006, 02:16:35 AM
USPS's airmail service is pretty good, surface mail on the other hand is horrible, I've had some things sent surface mail and they take 3-4 months to turn up!

Righto, opened the package, it contains the basic instructions, 4 washers, a piece of conduit (for the spacer) about 420mm long, and 2x .9 springs roughly 380mm long, 25mm diameter. Not exact measurements due to the paper wrapping.

Quote from: galahs on September 26, 2006, 07:40:29 PM
Now stop talking and put em in!  :thumb:
Waiting on new pads to turn up, and to hit 1000k since the last service to check out useage. Plan is to do the springs when the pads are off as the whole front is in pieces anyway. CCT also needs retensioning, starting to rattle again.
Title: Re: Fork springs.
Post by: brembo on October 03, 2006, 12:34:40 AM
Rightio, new fork springs are in and HOT DAMN what a difference, now the rear end is severly lacking  :2guns: Front is 100x stiffer, makes the ride a little coarser, but the front end is alot more planted in the corners. Alot less wallowing from the front end in all typres of riding. I've had to increase the preload on the rear from 5 to 6 to stop its becoming a rocking horse when I brake, seems to have helped a touch, will need to test it out more.

Now onto more pressing issues, excess oil consumption  :2guns: :mad:
Title: Re: Fork springs.
Post by: galahs on October 03, 2006, 09:20:37 AM
What oil do you use?


I switched to Castrol 10W-60 synthetic and found it to be awsome. Havn't had the level drop at all over 5,000km's of fairly hard and hot riding.

Its expensive though at around $60-70 for 5 litres. I always pick mine up when SuperCheap Auto have their 20% of 1 day sales.
Title: Re: Fork springs.
Post by: brembo on October 04, 2006, 12:28:28 AM
Using Motul 5100 10W40, had it at the F mark on the dipstick, now it's at the L mark, 800km later. Something definitely isn't right.
Title: Re: Fork springs.
Post by: galahs on October 04, 2006, 06:43:50 AM
Sheesh!

That aint good.

Signs of burning or leaks?
Title: Re: Fork springs.
Post by: brembo on October 04, 2006, 05:13:02 PM
No oil leaks to be seen, no smoke that I can see at idle, I can't really look at the pipe when I'm out and about riding it, so no idea if it's blowing smoke when I give it a little, or when I back off the throttle.
Title: Re: Fork springs.
Post by: galahs on October 04, 2006, 06:51:15 PM
You can try using a higher weight oil like the 10W-60 or Penrite 15W-60. Its possible the oil is thinning out too much when ythe oil is hot.

If that doesn't work, you could be in for some expensive / difficult repairs like new piston rings  :icon_confused:
Title: Re: Fork springs.
Post by: brembo on October 04, 2006, 07:17:35 PM
Any particular Penrite oil? Their website isn't the most informative thing around.

EDIT: Their little oil recommendation thing says "HPR Gas 10 SAE 10W-50" but it seems to say that for every bike they list.
http://www.ew2.lubesinfo.com/frameset.asp?sid=205&bid=79&sc=1205&langid=16

At this point, I'm willing to try any form of oil, it's a shiteload cheaper than a rebuild!
Title: Re: Fork springs.
Post by: Jughead on October 04, 2006, 07:37:49 PM
Don't mean to Butt in and Seem like a Know it all. BUT could it be that it is the Oil your using being Semi  Synthetic that it is Seeping Past everything and Being Burnt?Maybe before Tearing everything Down you Should Switch to Regular Dino Oil and see if it stops using oil. :dunno_white: Just a thought.I'm not a Know it all.Just a Know it Some. :laugh: :laugh: I have Heard of Car Engines that started using a Typical Brand of oil and After the Oil Brand was Switched they would stop using as Much if any at all. :thumb: :thumb:
Title: Re: Fork springs.
Post by: galahs on October 05, 2006, 10:12:34 AM
I was thinking Penrite HPR 15 or if you can afford it try the Castrol Edge 10W-60  :thumb:


Jughead is right, I'd be trying different oils before deciding to do a engine tear down.
Title: Re: Fork springs.
Post by: brembo on October 08, 2006, 08:11:29 PM
Picked up some Motul 1000, only non-(semi)synthetic oil I could find, 20W50 though. I'll put a few hundred km on the bike then drop the oil out and put this stuff in. See how it goes for 1k km after that.
Title: Re: Fork springs.
Post by: brembo on February 06, 2007, 03:53:04 PM
Forum resurrection!

Recently had the 48,000km service done on the old GS, also had the forks raised int eh clamps by 5mm, which seems to have offset the effect of putting stiffer springs in the front end. Now it isn't as flighty as it was. All in all, well worth the trouble.