Attention R6 Fork Riders! Settings Wanted!

[ChanceCoats123]

As one could figure out from the title, I'm looking for some advice from other riders with the R6 fork conversion. I had them dialed in nicely last season, but I've since taken ~ 10 lbs from the front of the bike with my naked conversion. I noticed a borderline tank slapper yesterday under hard acceleration over some bumps (with a minor lean angle) and I'd like to get the nose more planted.

Unfortunately, I don't have anyone else to help me measure static sag so I'm going to try my best to do that today and get it within spec (around 25mm on the front/rear)

I'm 6' tall and I weight 180 lbs, so more like 190-195 with gear on.

If you guys don't mind, I'd love to see some height and weight numbers as well as the preload, rebound and compression damping settings you've currently set on your R6 forks so I can compare and see perhaps a baseline I should aim for before I ride and tweak.

Many thanks in advance!

 

[MattR302]

Home - SB Suspension these guys are located in the Chicago area. They can probably give you a basic sag setup for cheap and offer you advice on the other settings.
Settings will vary based on what springs and oil you've got in them.

 

[ChanceCoats123]

Home - SB Suspension these guys are located in the Chicago area. They can probably give you a basic sag setup for cheap and offer you advice on the other settings.
Settings will vary based on what springs and oil you've got in them.

Thanks for the link, but I'd like to see if I can't do it myself. Learn how to do it right once and I'll never need help in the future. I enjoy working on my bike and I'm too damn cheap to have someone else do it when I could just learn myself.

I did head out to the garage though. It's stock springs and oil from a 2004 R6 (they have been serviced between release and now). I've got the preload adjuster at 3 lines, and the compression and rebound both got screwed in all the way and backed out fully. They're now sitting right around the halfway mark on both sides. I'll take it out later when it warms up a bit and see how it feels. I did my best to calculate static sag and got right around 25mm with these changes to the front.

 

[Hellgate]

You should be close at 25mm.

Sport Bike has a very detailed article on suspension set up. A Google search should find it. You'll need a buddy to help but it really transforms the bike.

 

[Erci]

Can't give you exact figures, since I'm at work right now.. not that it'll help a great deal since my R6 fork is on... R6.. on and mine's 05, so the fork is inverted, but here's what I'm fairly certain about:

If your preload is screwed in to show 3 lines and your rebound is backed all the way out and the oil is stock weight.. your fork is definitely too bouncy right now.

There are lots of videos out there on fully adjustable fork setup.. books too. The name you want to look up is Dave Moss.. look for his videos. He shows you how to check rebound after you get the sag set up. He also explains compression (and how it's a very fine adjustment).

Having said that, a tank slapper can happen with a perfectly adjusted fork.. things like geometry and technique have lots of influence on front end behavior.

I would definitely try to learn how to set the fork up close to perfection, but I wouldn't expect it to be a magic cure. The idea is to have as much traction as possible .. that's where a proper setup should help.

 

[ChanceCoats123]

You should be close at 25mm.

Sport Bike has a very detailed article on suspension set up. A Google search should find it. You'll need a buddy to help but it really transforms the bike.

That's the site I was reading from last night that got me thinking I should check and make sure my sag and other settings are at least close to where they should be. Lots of good info on that site. :thumbup:

Can't give you exact figures, since I'm at work right now.. not that it'll help a great deal since my R6 fork is on... R6.. on and mine's 05, so the fork is inverted, but here's what I'm fairly certain about:

If your preload is screwed in to show 3 lines and your rebound is backed all the way out and the oil is stock weight.. your fork is definitely too bouncy right now.

There are lots of videos out there on fully adjustable fork setup.. books too. The name you want to look up is Dave Moss.. look for his videos. He shows you how to check rebound after you get the sag set up. He also explains compression (and how it's a very fine adjustment).

Having said that, a tank slapper can happen with a perfectly adjusted fork.. things like geometry and technique have lots of influence on front end behavior.

I would definitely try to learn how to set the fork up close to perfection, but I wouldn't expect it to be a magic cure. The idea is to have as much traction as possible .. that's where a proper setup should help.

To be clear, the preload is at 3 lines, and the rebound damping is at half. I screwed them in all the way and then backed out as far as they go so I could figure out how many total turns they could make. Then I divided by 2 and set it approximately in the middle.

I'll look up those Dave Moss videos now since I'm just sitting around twiddling my thumbs. :thumbup:

 

[FinalImpact]

I'm running closer to track type but don't track so this may not be a value add.

Bikes at 12mm
Bike and rider 31mm on the nose (29 on the rear).

If you really lost 10lbs off the nose thats a good amount and over bumps while on the throttle it impacts the back also. That said, you may have too much rebound up front or too MUCH POWER! haha!
- Too much rebound could show by the nose packing down over bumps. i.e. the forks are not extending between bump intervals and the nose gets lower and lower. But while on the gas, this makes the nose light as its loosing contact with the ground.

There are several videos out there and one has the guy setting the Compression first and then the rebound. I find this it NOT the best way as adding compression **masks** what we feel and we don't notice the actual effects of rebound control.

- In short (what works for me); back out the compression fully and dial in some rebound. Bounce the nose while standing to the side of the bike. Dial in a controlled amount of rebound such that the nose doesn't SHOOT up or come up too slowly. You don't want pack down (too much rebound).

Dial in ENOUGH compression that while bouncing you can't bottom the forks but not so much that they are stiff. Test drive KNOWING IT MAY BE UNSTABLE!!! The goal is to asses if there is enough rebound to control the return rate. Only add comp to make it safe to ride (its more of a user preference anyway). Play with the rebound - add some take it away. Find a happy spot.
- Now dial in the amount of compression that allows MOST of the suspension travel to be consumed, but keep those ROUGH ROADS in mind as you DO NOT want it to bottom out on anything but the worst road conditions.

- Thats it. Rebound first, then compression to what feels good. Also, rebound values from bike to bike should be counted as turns out, as the fork assembly process can alter the turns in count based upon the distance the cap is installed on the damper rod.

->> last little bit: The rear shock is part of your equation too. The OEM shock lacks compression and rebound damping. i.e. when hard on the throttle, the rear squats (lack of comp damping), then when you let off, it shoves the nose down as it lacks Rebound control. This directly impacts the light feeling you created this thread from! Money will fix that! (Ohlins....) :thumbup:

 

[FinalImpact]

I've tossed this up at various times... Threw it on your Visitor page too.

Visit this!
Tire wear patterns.... Race Track Motorcycle Tyre Wear Guide - Types and Causes
Bike setup vid w/ Dave Moss.... https://www.youtube.com/watch?v=Ikjw4IheeF4
Bike Setup Tech article..... Motorcycle Suspension Set-up

In my build thread at --> post 2 & 7 have some of my settings. Because springs deteriorate at different rates we can't compare preload values (lines at adjuster). Plus our loading is different (Naked vs faired).

Below is the starting point and I know [MENTION=14469]motojoe122[/MENTION] just did R/T springs @0.95mm/kg and hit a home run landing in this range too. Faired bike and roughly same weight. Bike and rider around 35mm sag / 13 mm bike only.

One article says Street bikes need 10 - 15 mm of static sag (bike only). Too low of bike sag means your spring rate is too high and the forks can be topped to easily.
>10mm = need higher rate springs
<10mm = need lower rate springs

Then shoot for your rider value in the low 30's to better center the fork in its range of travel for street use.

 

[ChanceCoats123]

Randy, I think you hit it right on the head. I just did some adjusting.

1 Line of preload gives a bike sag of 16mm and a rider sag of 28mm. I went 5 clicks out for rebound damping (rebounds up once from a hard push with the front brake on, then settles back down) and 7/8 clicks out for compression damping and took her for a spin. In turns, the front end is absolutely planted and felt very responsive.

Unfortunately, this is the part you hit right on the head... The rear is completely out of where it should be. It's on setting 7, and the bike squats and lifts a fair amount under acceleration and braking. Looks like I'll need to re-valve/re-spring or move up in the world of adjustable rear suspension. I should have known this before... If you press down on the center of the bike (when off the center/side stand), the rear drops more and rebounds much quicker. Since both the compression and the decompression are off, there probably isn't much I can do in terms of adjusting preload to help it out (any decrease in one symptom would just make the other worse).

 

[FinalImpact]

Sad but true -

So, while riding, stand up and jump on the pegs. Watch what the bike does. i.e. Front rate of compression vs rear rate of compression/Compare the rates. Then watch the return rates. Its ok to run the nose a bit softer. EDIT: you want them fairly well balanced. We don't have highspeed adjusters so near equal is better. It makes the bike track in the corners much better.
For me it was squat on launch was too squirrelly as the rear was compressing too much and simply not enough rebound as it comes up to speed so it would push the nose down quickly if that makes sense. Like the rocking horse effect.. That's where I threw in the towel and had the R1 shock revalved. The guy hit a home-run and the bike is agile and predictable.
Until action can be taken to correct the rear, your goal **may be** a compromise to get the front and rear doing ** nearly ** the same thing at the same time.

So, set the nose to mirror the back. Soften both comp/rebound rates. It will corner more predictably over degraded surfaces, uneven bumps/dips in the corners. The closer we pay attention to what we do and how it acts/interacts with the conditions you begin to see the imbalance and short comings of some components.

 

[ChanceCoats123]

That sounds like a pretty good idea. I'll keep track of my current fork settings and loosen them up a bit to match the back. I had already noticed what you mentioned, and the back is noticeably softer when I jump on the pegs. It's close in the sense that I probably only need to back the preload off one level and the rebound by a couple clicks. Thanks for the help, fellas. I got the bike out for a bike and the front is really responsive now.

 

[beatle]

What did you settle on? I'm looking to start tuning my forks and we're within 5 lbs of each other.

 

[ChanceCoats123]

What did you settle on? I'm looking to start tuning my forks and we're within 5 lbs of each other.

I actually changed things up quite a bit. I read a different guide to get my suspension set up because I was also dialing in the R1 rear shock I installed. The overall settings I settled on are:

Rear shock (R1 w/ FZ6 spring):
Preload = 1
Compression = 8 clicks out
Rebound = 8 clicks out

Forks (R6):
Preload = 5 lines showing
Compression = 7 clicks out
Rebound = 5 clicks out

Keep in mind that my fork preload can be much lower than stock bikes because I did the naked conversion and the front is so much lighter.

These settings may not be exactly dialed in yet, but I've ridden for the past week or so with these settings, and the bike is SO MUCH more predictable in turns.

When I first installed the R1 shock, the rebound was WAY too many clicks out and it was like driving a Cadillac the ride was so plush. I would seasaw over small bumps. Now the front and rear compress and rebound at very similar rates and the bike glides over bumps with the suspension compressing, rebounding once and returning to normal in a nice quick motion. The rear tire is freaking planted now.

 

[beatle]

I totally forgot to check compression last night after finishing the swap. I started with rebound @ 6 out and preload @ 4 lines (on line #4). I also have 8mm of fork showing above the triple, not including the cap. Couldn't really assess the suspension that well on this morning's ride into work since it was misty rain and I was gingerly negotiating every turn.

I have a Penske double adjustable on the way for the rear - looking forward to it.

 

[FinalImpact]

Also, with all these used parts, be sure to verify fork action by backing OUT all damping control. Then say, apply 5 clicks rebound to left fork, bounce it. Back it out. Apply 5 clicks to right fork. Bounce. DO they feel and DO the same action!?
Repeat with other settings and comp damping....

Chance, are your forks flush or pushed up the triple? What sag numbers did you come up with front and rear?

 

[ChanceCoats123]

Also, with all these used parts, be sure to verify fork action by backing OUT all damping control. Then say, apply 5 clicks rebound to left fork, bounce it. Back it out. Apply 5 clicks to right fork. Bounce. DO they feel and DO the same action!?
Repeat with other settings and comp damping....

Chance, are your forks flush or pushed up the triple? What sag numbers did you come up with front and rear?

Forks are flush up with the top triple, but I might move them down a bit to see how much quicker I can get the bike to turn in. I never measured sag on the front and the rear spring is just slightly too hard. Static sag is 5mm and rider is 25mm in the rear. I never checked the front because what I read put more emphasis on getting the full range of travel than setting sag numbers perfectly. The ride is comfortable and the front and rear mirror each other very well now.