ADVrider

Go Back   ADVrider > Bikes > GSpot > Parallel Universe
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 07-25-2010, 01:44 PM   #16
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
A bit more info....

Keep in mind a set of RXV stock forks come with a .475 springs & there are two other options - a stiffer .50 spring or a softer .45.
http://www.af1racing.com/store/Scrip...idCategory=180

The stock springs on our bike seems to be a .44 (or .46?) so I am going to try the .50 springs and see how I like it. From the research I have done the valve work is more important than the spring rate provided the springs are within proper sag settings.

I need to look up what the proper sag setting are for a bike like this. Any info is welcome (sources too please... )

I am considering putting the forks on before the revalve work so I have a reference ride on them, have the work done and feel the difference. Then make decisions from there on what is needed.
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-25-2010, 01:46 PM   #17
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
Quote:
Originally Posted by -W-
"I was also thinking of changing first [the] whole forks to WP's, but [a friend who is helping me with the project] said that there isn't any need to do that if you can "Shiver original ones". Reason why people doesn't necessarely like original Shiver forks is the amount of preload and way they have been usually valved by the factory - and he was right.

Personally I wouldn't change these [RXV Shiver'd] forks now for stock WP forks. I have ridden one 990 Adventure and those forks aren't as good as stock as these Shiverred & revalved are. Those WP's would need to have more stiffer springs and revalving to be better or same than these are.

It is a great mod (and relative cheap now when we know what we have to buy for conversion - I had to bought couple of different kind of forks to find the right parts -> my conversion wasn't cheap but it is still worth of every penny), but only if you revalve them by some professional guy who really knows what he is doing. Just don't save on revalving, that is my advice;)

And remember to drill a hole for oil to that spacer (there is a small hole in the damper rod and there has to be maching hole at the spacer too). And also drill&tapper a hole for lock nut to the spacer to keep it at it's place. Mine has M4 locknut.
Quote:
Originally Posted by -W-
Right spring rate depends what do you want from fork compared to original one, how long travel you will have (stock 230mm or more?), how heavy you are and what kind of riding do you do.

If we compare spring rates from "similar weight / kind of bikes"..:

1. KTM 990 Adventure has 0.49 springs in stock model which has less travel than F800GD and weight 15 kilos more. S-model has 0.48 spring because it has more travel than stock model and also more travel (15mm) than F800GS.

2. KTM 950 Superenduro has 0.59 springs and has much more travel than F800GS (255mm - 25mm more than F800GS. It weights the same than F800GS but it has been built to be used as a real dirtbike - suspernsion is therefore real stiff and [some say] bit too harsh for most of the users.

Now you can ask you self that are you going to ride with your F800GS more harder than Superenduro is built to be ridden..? I don't thinks so, so why to have then stiffer springs than Superenduro has? Stopping of bottoming your fork is meant to be done by adjusting your forks oil level and base valve, not by putting some over stiff springs.

Then again you might try 990 adventure and see how you like it's front fork? I felt it was a bit too soft for my riding style (I propably sometimes ride much harder than F800GS is originally meant to be ridden or normal 990 Adventure and sometimes also in very highs speeds at gravel roads).

So I would say go or those 0.50 springs you already have if you aren't too heavy your self, you don't ride trails with head size rocks, you like plush ride and you aren't that much of the "spin the wheel guy".

If you like to fly through rock gardens, sprin the wheel at gravel roads at high speeds (80-140km/h), or you are heavy guy go for the Öhlins 0.55 springs. Then if you want to have "bullet train" for extremely rough roads and trails and/or you are a big guy go for the 0.60 Bitubos.

But in the end you should measure the race sag etc from your bike when you are on it, decide the correct preload and then calculate the spring. It is impossible to say what spring is best for you (because valving and oil level has also big effect to the feeling), but starting with those 0.50 isn't a bad thing since you already have them.
.
__________________
Ride more, bark less

Gangplank screwed with this post 07-25-2010 at 01:55 PM
Gangplank is offline   Reply With Quote
Old 07-26-2010, 10:18 AM   #18
big sky mt
Adventurer
 
Joined: Sep 2007
Location: Badlands of eastern MT
Oddometer: 30
Sag measurements

[quote\]I need to look up what the proper sag setting are for a bike like this. Any info is welcome (sources too please... )[/quote]

Here is a quickie for the sag measurements.

http://www.vstrom.info/Smf/index.php/topic,1539.0.html

It's for a larger bike but should work by doing the math.
big sky mt is offline   Reply With Quote
Old 07-26-2010, 12:10 PM   #19
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
The basics from there....

Quote:
Spring Preload (Sag Adjustment)


Preload on the spring/springs is very important because it affects the height of the motorcycle and the fork angle. Consequently, handling characteristics can be changed, even negatively. Proceed as follows, it will be much easier and really should be done with two people.

A. Place the motorcycle on a stand.
B. Left up the rear end to the fully extended position.
C. Measure the distance from a point (can be marked on a piece of tape) immediately above the rear axle to the center of the rear axle. This a R1.
D. Make a similar measurement on the front axle with the fork fully extended. This is F1.
E. Allow the motorcycle (without rider) to apply a load and repeat the measurements. R2 & F2.
F. Then take the same measurements with the rider (in full riding gear) and equipment on the motorcycle. It is important that the rider have the correct riding posture so that the weight is balanced on the front and rear wheels in the same way as when riding. R3 & F3.

Your measurements should be within the following ranges.
Without Rider:
Rear 10-15 mm (R1-R2)
Front 25-30 mm (F1-F2)

With Rider:
Rear 35-50 mm (R1-R3)
Front 35-45 mm (F1-F3)

If these ranges are not meet, adjust preload accordingly and do it again.

Once single up adjustments are correct, perform step F above to determine camping or SO load adjustments. Mostly the rear preload should be effected enough to warrant adjustment.

These are sport-touring settings. If you do a lot of twisties, the “With Rider” measurements for the rear should be about 10 mm less. If you like it a little cushier, the “With Rider” measurements for the rear should be about 10 mm more.

Rebound Damping (Rear)

Start by adjusting the rebound damping to the OEM setting: Turn the adjuster screw all the way in clockwise. Then turn it back out about 7/8's of a turn. Take a test ride, find a nice bumpy street for testing purposes. The V-Strom shock rebound damper adjust has a range of about 2 1/4 turns. Full hard is fully clockwise & full soft is fully counter-clockwise

If the motorcycle feels unstable, loose and rather bouncy, then the rebound damping should be increased. Begin by turning the adjustment screw 1/4 turn clockwise. Continue to test ride & increase in 1/4 turn increments until you feel it getting hard & bumpy. At this point adjust 1/8 turn back and test again.

If the motorcycle is hard & bumpy, especially over a series of bumps, then the rebound damping should be reduced. Adjust in 1/4 turn increments counter-clockwise and test as above until the bumpiness is gone.

There is a happy medium in there somewhere. If all else fails, there is always Wilber’s, Sonic, & Race Tech!
Excellent info. Thanks!!
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-27-2010, 07:38 PM   #20
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
Got the call today.... "your parts are ready."

$130 bucks. They made a special aluminimu collar piece to hold them in the lathe. If anyone needs to get it done:

J-B Machine - ask for Dale
(775) 359-9856
1450 Greg Street
Sparks, NV 89431-5927

Here is a pic:


and with the bottom adjuster in place:


Dropped them off at Ed McCoy - McCoy's off road. he's making the spacer to shorten the travel and revalve. Can't wait till Friday!!
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-27-2010, 07:42 PM   #21
Camel ADV
aka Oso Blanco
 
Camel ADV's Avatar
 
Joined: Mar 2009
Location: Calgary, Alberta, Canada
Oddometer: 1,293
Quote:
Originally Posted by Gangplank
Got the call today.... "your parts are ready."

Dropped them off at Ed McCoy - McCoy's off road. he's making the spacer to shorten the travel and revalve. Can't wait till Friday!!
We are both on about the same time line. Fingers crossed it works as planned!
__________________
Camel Tank auxiliary fuel tank for F series BMW twins. www.Camel-ADV.com

Proud member of Team Canada for the 2014 BMW GS Trophy

AT-BZ-CA-CN-CO-CR-CZ-CH-FR-DE-GB-GT-HN-IE-JP-KZ-KR-LI-LU-MX-NL-NI-PL-RU-SV-UA-US
Camel ADV is offline   Reply With Quote
Old 07-27-2010, 11:58 PM   #22
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
Yep. My bottom feet fit like a glove. I've got high hopes for the rest of the project.
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-28-2010, 07:58 AM   #23
-W-
Flying Finn
 
Joined: Nov 2009
Location: Finland
Oddometer: 193


I have done now 10tkm with mine Shiver'ed forks without any problems - it works if done correctly.

By the way check that if they remembered machine little chamfer/roundin inside the lower leg and to that part were the bigger machined hole turns to slightly smaller machined hole. That edge shouldn't be completely sharp or it will 'cut' slice from your base valve's O-ring seal (or damage it) when you push the valve to it's place - seal could start to leak later on.
-W- is offline   Reply With Quote
Old 07-28-2010, 12:31 PM   #24
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
Yep. Mine is baby's butt smooth.

BTW - I was discussing with my revalve guy the 40mm spacer to get it back to stock. He was not sure what you meant about the oil hole needed in the spacer. He said he had not seen one done that way before. He is going to take them apart, take a look and give me a call.

Do you happen to remember the overall length of the RXV forks vs. the stock forks?

Also the travel is 230 for stock and 300 for the RXV Shivers correct?
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-28-2010, 01:46 PM   #25
-W-
Flying Finn
 
Joined: Nov 2009
Location: Finland
Oddometer: 193
There is a small hole (like 1mm diameter or so) drilled through the hollow rod (which has the rebound adjusting rod in it) just couple of cm up from the rebound valve. This hole will be covered with that 40mm spacer if you don't drill similar or bigger (like I did) hole to spacer. Probably the hole isn't necessarely needed, but I didn't want to take any chances because there is definitely some reason why original Shiver forks have this small hole (both, Factory and RXV, forks which I have taken to parts have this hole).

Don't remember the overall lenght of the forks, but you can pretty easily measure that by your self. How ever it is quite impossible to use RXV forks as they are in F800GS since upper tubes are much lower in RXV forks - your bash plate would go 'trough the groung' at full compression..

And what comes to stock travels you are correct.
-W- is offline   Reply With Quote
Old 07-28-2010, 02:44 PM   #26
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
Quote:
Originally Posted by -W-
There is a small hole (like 1mm diameter or so) drilled through the hollow rod (which has the rebound adjusting rod in it) just couple of cm up from the rebound valve. This hole will be covered with that 40mm spacer if you don't drill similar or bigger (like I did) hole to spacer. Probably the hole isn't necessarely needed, but I didn't want to take any chances because there is definitely some reason why original Shiver forks have this small hole (both, Factory and RXV, forks which I have taken to parts have this hole).

Don't remember the overall lenght of the forks, but you can pretty easily measure that by your self. How ever it is quite impossible to use RXV forks as they are in F800GS since upper tubes are much lower in RXV forks - your bash plate would go 'trough the groung' at full compression..

And what comes to stock travels you are correct.
Yep. Got it & thanks. I appreciate the info. I talked to him about the oil hole in the damper rod. he didn't seem to think a hole was needed. I'll let him figure that one out and will report back what he says.

RE: length. I took the forks apart before I remembered to measure them. He will probably put them together and see the difference. I trust your 40mm measurement and gave it to him. Will report back on that one too.

BTW - thanks for being the PIONEER on this one. Great and easy fix so far.
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-28-2010, 05:27 PM   #27
Gangplank OP
Advenchaintourer
 
Gangplank's Avatar
 
Joined: Jul 2003
Location: Las Vegas
Oddometer: 2,309
Quote:
Originally Posted by -W-
There is a small hole (like 1mm diameter or so) drilled through the hollow rod (which has the rebound adjusting rod in it) just couple of cm up from the rebound valve. This hole will be covered with that 40mm spacer if you don't drill similar or bigger (like I did) hole to spacer. Probably the hole isn't necessarely needed, but I didn't want to take any chances because there is definitely some reason why original Shiver forks have this small hole (both, Factory and RXV, forks which I have taken to parts have this hole).
Got it all figured. From above I notice that the stock forks are 890mm. I'll see if someone can re-measure and confirm that for me.

The other issue of the hole in the damper rod being covered by the spacer is going to be solved by the use of a topout spring instead of a solid spacer. My suspension guy thinks that the spring will work better and we will cut it to the right length (40mm give or take) to reduce the travel down to 230mm.
__________________
Ride more, bark less
Gangplank is offline   Reply With Quote
Old 07-29-2010, 12:35 AM   #28
-W-
Flying Finn
 
Joined: Nov 2009
Location: Finland
Oddometer: 193
Question

There is already that kind of topout spring inside of the dampening cardridges of RXV and other Shiver forks. So if you use second topout spring for reducing the travel that spring should be really stiff so that it won't anymore 'bend'.

Normally all the travel reducements for enduro bike forks (when they use same forks for supermoto and iceracing) are done by using solid spacers - at least in this part of world;) What is good in solid spacer is that you can lock it to it's place with locknut and therefore it stays (no matter what) at the bottom of the damper rod. If you don't lock it (or you spring instead of it) it may move up and down during suspension travel and leave marks to damper rod and then the upper cardridge seal doesn't seal that well if there is marks/grooves at the rod surface.

Again I'm not sure if this will hapen in reality or not, but I didn't wan't to take any changes what comes to reliability. After all it is an adventure bike (at least that is my goal with this bike;) and therefore reliability of every mod which I do for my bike has to be at top level. That is one of the reasons why I didn't want to go for gas pressurised gardridges like Bitubo etc..


And I'm glad if I can help you guys with this mod since I have got so many good advices and inspirations from this site that I am only happy if I can 'pay some of that' back by sharing this fork mod.
-W- is offline   Reply With Quote
Old 07-29-2010, 04:03 AM   #29
blacktiger
Tigers R great.
 
blacktiger's Avatar
 
Joined: Nov 2005
Location: St.Leonards on Sea, England.
Oddometer: 3,388
Why?

Seems like an awful lot of time, money and work when all you really needed was different springs and oil viscosity.
__________________
2002 black Tiger955i, 72000 miles and counting.
2012 black Tiger800XC, 31000 miles and counting.
blacktiger is online now   Reply With Quote
Old 07-29-2010, 04:20 AM   #30
-W-
Flying Finn
 
Joined: Nov 2009
Location: Finland
Oddometer: 193
Quote:
Originally Posted by blacktiger
Seems like an awful lot of time, money and work when all you really needed was different springs and oil viscosity.
Yeah, right...
-W- is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 01:31 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014