I was in on the first group buy with the Wilburs suspension components. Currently I get a lot of front end dive and at times it wants to bottom out. Is there something that I can do to change this. I apparently missed the group buy at GP suspensions, but I really don't want to spend $600.00 either. Is there another spring that I can buy that will make this work better for me. Looking for some answers. Thanks
Front end dives or bottoms out
- Thread starter twiggy
- Start date
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quicksilver
So.., how fast does that thing go?
Have you been monkey-ing with the front end.
(your post history suggests yes)
1. Let's not run past the obvious.
If you haven't already done so, open up your manual and carefully read about front end adjustments.
2. To answer you specific question. Yes, stiffer springs are available for ~$120. Several sources including GP suspension.
To get more in depth. What year, how many miles, what work has been done.
Note my signiture line.
(your post history suggests yes)
1. Let's not run past the obvious.
If you haven't already done so, open up your manual and carefully read about front end adjustments.
2. To answer you specific question. Yes, stiffer springs are available for ~$120. Several sources including GP suspension.
To get more in depth. What year, how many miles, what work has been done.
Note my signiture line.
twowheelnut
R.I.P. Our Motorcycling Friend
You can adjust the preload and compression damping on the forks to 'stiffen' up the front end. Also, you can/should change the fork fluid periodically as it does have a service life an may want to think about upping the oil weight as well. Cheapest fix you're gonna find.
HaulinAshe
Well-known member
Twiggy, I'd offer to help you, but suspension requires information, lots of it.
Bike & year?
What shock & springs, front and rear?
Front preload?
Front compression?
Front Rebound?
Rear rebound?
Rear compression (if aftermarket)?
Rider sag?
Rider weight?
Typical load (two side bags, top bag, gear, two-up)?
Anything less than this and there's no science involved, only conjecture.
Conjecture #1: Don't forget that the thing which influences front suspension the most is the rear settings.
Bike & year?
What shock & springs, front and rear?
Front preload?
Front compression?
Front Rebound?
Rear rebound?
Rear compression (if aftermarket)?
Rider sag?
Rider weight?
Typical load (two side bags, top bag, gear, two-up)?
Anything less than this and there's no science involved, only conjecture.
Conjecture #1: Don't forget that the thing which influences front suspension the most is the rear settings.
Jeff thanks for trying to help me out
2005 fjr
240#
origional Wilburs 640 660 625 629 I don't know if those help at all
Rebound 12
Pre load 17
Springs 59/59-100-150 AA 329mm
typical solo with out bags
How do you figure out rear compression and rider sag.
OrangevaleFJR
R.I.P. Our FJR Riding Friend
I can't remember ever bottoming out my forks...do you have enough fluid in them? I used to adjust the rigidity of forks with more, or less fluid before shocks had all these fancy adjuster things.
The only datapoint that is missing to me is mileage? I have 45K on my '05, am about 250# and the shocks were WAY too spongy and wore out. Could be mileage related.
Charlie Hoss
Well-known member
Twiggy,
I bought a pair of Wilbers springs used from someone on this forum. Don't know the weight. They were WAY too stiff the 1st time I put them in.
There is extensive info on the forum about installation. One of our guys showed how to figure and cut the spacer tube on the damper rod to get the proper preload. You may be able to add to the spacer a small amount. The specs call for the oil level to be measured with the spring out and the fork tube fully compressed, 100mm or about 4". You might get stiffer spring action or less bottoming with a *slightly* higher oil level, perhaps 3 1/2 ". Did the washers go back in correctly? I have an '05, also, and weight about 195 ( I'm working on that!).
Correct fork oil is a question that you'll never find the perfect answer for. I used Belray 5 weight, non-synthetic, and it works fine for me and is available locally.
If you need to ADD to the spacers, I bet you can find short spacers that would fit, at most hardware stores in the slide-out drawers in the bolt dept. You would most likely have to experiment with and perhaps cut the length.
The Wilbers were considerably longer than stock. I think correct installation and adjustment would fix the problem. Good luck.
Charlie
I bought a pair of Wilbers springs used from someone on this forum. Don't know the weight. They were WAY too stiff the 1st time I put them in.
There is extensive info on the forum about installation. One of our guys showed how to figure and cut the spacer tube on the damper rod to get the proper preload. You may be able to add to the spacer a small amount. The specs call for the oil level to be measured with the spring out and the fork tube fully compressed, 100mm or about 4". You might get stiffer spring action or less bottoming with a *slightly* higher oil level, perhaps 3 1/2 ". Did the washers go back in correctly? I have an '05, also, and weight about 195 ( I'm working on that!).
Correct fork oil is a question that you'll never find the perfect answer for. I used Belray 5 weight, non-synthetic, and it works fine for me and is available locally.
If you need to ADD to the spacers, I bet you can find short spacers that would fit, at most hardware stores in the slide-out drawers in the bolt dept. You would most likely have to experiment with and perhaps cut the length.
The Wilbers were considerably longer than stock. I think correct installation and adjustment would fix the problem. Good luck.
Charlie
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Put a plastic tie wrap around the fork tube. With the front suspension fully extended (on the center stand) push the tie wrap down to the fork seal. Gently push the bike off the center stand and sit on it to depress the suspension to the normal "sit in" position. Put the bike back on the center stand and extend the front end. See how far the tie wrap was pushed up the fork tube. That will tell you your sit-in. I like it to be about 1 inch to 1.5 inches. If it sits deeper than this then you need to add preload to the front springs with the preload adjuster. If they are maxed out then dissassemble the fork and add a spacer to the fork spring to pick the front end up. Some experimentation required. But you must get the initial sit in correct or the suspension travel will be "used up" before you even hit a bump. Make sure the fork oil is fresh and dial in the adjustments for compression and rebound to suit. One thing that can dramatically help if the front suspension is bottoming is to increase the fork oil level. Measure where you are at with the fork oil level and pour in more oil to bring the level up .5 inch or so. Ride and try. Add another .5 inch and ride and try. The reduced air volume in the fork will increase the rate of the fork as it nears full compression and resist bottoming.
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