BARF - Bay Area Riders Forum

Go Back   BARF - Bay Area Riders Forum > Moto > General


Thread Tools Display Modes
Old 11-13-2020, 08:30 AM   #1
Frisco's Avatar
Contributor +

Join Date: Nov 2005
Location: El Cerrito
Motorcycles: Yammies Ď17 FZ-09 and '13 FJR
Name: Carl
Tweak that Suspension!

Budman asked me, and you, to start posting up more moto stuff....,

My FZ-09 had been behaving strangely in high speed corners. The front end would chatter a bit, very disconcerting. I had had Jason at JPH suspension set up my bike a couple years ago, but others had done little adjustments since.

Honestly, suspension seems like a bit of a dark art to me, but I gave it a think and decided it was probably my fork rebound. Per my reasoning, I needed more rebound damping as the front end was coming up too quickly after hitting small bumps. Two clicks of rebound later...... damn, now itís really bad! Iíd made my problem worse.

So, I was out in the garage scratching my head on this problem when I decided to have a look in my service records and found Jasonís settings from two years ago. My current rebound setting was 7 clicks in from his! I backed off 7 clicks and my bike is so much better! I think all that rebound damping was causing my forks to pack up when hitting small bumps at high speed.

First off, Iím totally chuffed that I was able to identify a suspension problem. Historically, Iíve really appreciated a well set up bike, but have had a hard time identifying particular problems. All it took was being 7 clicks off! Ha, ha...
Secondly, write stuff down! Itís easy for these settings to drift when you add a click or two here and there. Iím so glad I had Jasonís baseline to go back to.
Thirdly, read and think about this stuff and youíll start being able to identify specific problems and address them. Your riding will be safer and more fun!

Ride safe, yíall!
Frisco is offline   Reply With Quote
Old 11-13-2020, 09:00 AM   #2
Tally Whacker
Not another Mike
Tally Whacker's Avatar

Join Date: Jun 2016
Location: san diego
Motorcycles: BMW S1000R
Most of us riders simply ride the bike as it is, and don't fuss with all that adjustment nonsense. I mean, who understands any of that anyway? Just set everything in the middle and it's probably just fine.

At least, that was my experience for a long time, and it worked OK. Then, in 2004, I bought a brand new Speed Triple.

The road home nearly beat me to death! It was beyond abusive. Every join in the concrete freeway was a jackhammer blast straight to my spine.

The next day I spent some time and set the suspension (which was surprisingly adjustable, for OEM) to the manual's suggested settings for my weight. Riding became dramatically better.

Then, after a while, I decided that maybe better than that would be even better, right? So I took my forks in to GP Suspension (they were in Portland then) and they completely redid all the internals, and built me a Penske triple clicker. I installed the shock and forks, then did an open track day at Willow Springs, pulling in every few laps to make adjustments from what Dave at GP had set as baseline.

By mid day, I was aiming for the bumps, patches and ripples in the pavement to try to upset the bike, but it just wasn't having it. That bike was so dialed in that nothing would upset it, and I was going faster than I ever had before on that bike.

The most amazing thing about a perfectly set up suspension of that level of quality? It was both firmer and more plush at the same time. It was a dream ride, honestly.

Since that revelation, I've never looked back. Setting up the suspension properly has been the first thing I've done with every new bike I've owned. Well, except my supermoto. I can't figure that one out at all.
Tally Whacker is offline   Reply With Quote
Old 11-13-2020, 09:00 AM   #3

Join Date: Aug 2011
Location: SF
Motorcycles: 2nd Gen FZ1 / Oil Cooled 1200RT / '17 MT-09
Another thing to add about suspension is that the fork oil is often overlooked as a constant service item.

As a fellow FZ owner, I've also heard of other owners having good success in moving the handlebar a bit forward and lowering them down on the forks a bit.

Happy riding!
NoTraffic is offline   Reply With Quote
Old 11-13-2020, 09:10 AM   #4
Maddevill's Avatar
AMA #: 542337

Join Date: Jun 2005
Location: Hayward
Motorcycles: ZX14,GS750E, KTM 450/540
Name: Steve
When I bought my used ZX14, I rode it home on San Pablo Dam Rd. Holy crap ! It handled TERRIBLE. A few times I thought I was going to ride off the road. Really scary. As soon as I got home I set the suspension up to stock numbers and then adjusted damping just a bit. The difference was night and day. Now it handled really well. Apparently the previous owner just commuted on the freeway.
2 years ago I had Jason at JPH revalve both ends and put new cartridges in the forks. Another quantum leap forward. Then I rode a ZX14 with full Ohlins suspension. Drool...

If your nose runs and your feet smell, you're built upside down.
Maddevill is offline   Reply With Quote
Old 11-13-2020, 09:46 AM   #5
Hank Wong

Join Date: Jan 2011
Location: Mountain View
Motorcycles: 2001 BMW R1100RS
Yes, fork oil is often overlooked as part of a suspension fix.
I bought a 2019 Kawasaki Z900 In March knowing that there is no front fork compression adjustment. I mistakenly thought that I could just add a Race Tech cartridge emulator and swap out the springs like I did with my other Kawasaki. No joy! Kawasaki, in their infinite wisdom, made the Z900 forks unique and difficult to work on such that nobody, including Race Tech, would make a kit for it. The Race Tech rep says if they make a kit for it, the labor cost to install it would make it not cost viable compared to a set of drop in cartridges. At the high end, a set of Ohlins drop in cartridges would cost $1500. At the low end, a set of Adriani would be $1000. I did the next best thing and change fork oil weight to add compression by trail and error. It is a pain to pull the fork every time instead of turning a dial. But at least I only have to do the left fork. The right fork is inert and just along for the ride. After a few tries, I settled at a 60/40 mix of 10 wt and 15 wt fork oil, about 47 cSt @40C. Now the Z takes the torn up Moody road and Page Mill road in stride and at speed. I didn't have to spend the big bucks on a set of cartridge kit.

Last edited by Hank Wong; 11-13-2020 at 09:59 AM..
Hank Wong is offline   Reply With Quote
Old 11-13-2020, 10:05 AM   #6
dravnx's Avatar
AMA #3018349
BARF Sammich King
Contributor +++++++++
Barf Roadside Angel

Join Date: Dec 2012
Location: santa rosa, ca
Motorcycles: '12 DL650A GMF '17 DL650 '15 FJR1300A
Name: Jeff
I'm a big Dave Moss fan. I always get him to set up my suspensions and then record the settings. I can fine tune them but if I get too far out, I reset to Dave's and try some more.
I pulled the forks out of my FJR1300 with 51,000 miles and brought them to Dave's house ( he lives in Cobb now) and had him replace the fork oil. He put 20 wt in there and set the suspension to what he thought was correct. I was pretty skeptical but after I re-assembled the bike and took it for a ride I was pleasantly surprised. I then installed a Nitron shock. I was able to attend one of his clinics to tweak the suspension even more.
bike X miles=smiles
smiles ų bike=miles
smiles ų miles=bike.
It's simple math.
dravnx is offline   Reply With Quote
Old 11-13-2020, 10:19 AM   #7
Dogs best friend
gixxerjeff's Avatar

Join Date: Nov 2008
Location: Santa Rosa
Motorcycles: Some fast ones and some dirty ones.
Name: Derp
Dark art is right.
The two most viable options before you are
1) Let Dave Moss touch it
2) Sell a kidney and step up to some Ohlins.
Luck is the residue of desire.

You must be fast because I was hauling ass when I passed you.

Rich Cox
I miss you Rich.
gixxerjeff is offline   Reply With Quote
Old 11-13-2020, 10:32 AM   #8
Live Long
ThinkFast's Avatar

Join Date: Apr 2007
Location: San RiffRaph
Motorcycles: n. (pl), a two-wheeled device used for transportation as well as racing and other fun stuff.
Name: Tom
Suspension - for me it's been one of those things I more or less ignored, until I couldn't. Kinda like good acting - you know it when you don't see it.

When I first started racing I bought a set up SV and did 14 race weekends on it with around 80 starts my first season (CCS-Midwest). It wasn't until the end of the season that I even thought about looking at my suspension setup. It turned out I had a Penske triple clicker on the rear. Never touched anything on it that first season - and won three regional amateur championships.

It was very different story, though, when I moved up to experts the next season. Podiums were a thing of the past, and I found myself scrambling just to keep up with the back of the pack. So I hired a suspension tuner for the day and started learning how to work with him - that in itself is an art. He can't help you if you can't do two things:
  1. ride consistent lap times - at least within a couple tenths per lap or better.
  2. identify what the bike is or isn't doing in terms that you can then communicate to him.

That was a gamechanger for me - my laptimes immediately improved by a full second, and then over the next few weekends another half a second or more. Cool.

I'll save my street suspension story and lessons learned for another post. The short answer is: start by setting your sag. You can't tune your suspension until you've got the sag dialed. And it's pretty easy to do without fancy tools or Yoda-level knowledge.
ThinkFast Racing
ex-AFM #280

Last edited by ThinkFast; 11-13-2020 at 10:33 AM..
ThinkFast is offline   Reply With Quote
Old 11-13-2020, 11:35 AM   #9

Join Date: Dec 2009
Location: San Francisco
Motorcycles: 2012 DRZ 400s, 2018 Ducati Hypermotard SP
Name: Nathan
Dave set my bike up shortly after I bought it, 18k miles later I'm getting some odd tire wear, probably time to refresh for the fork and shock oil. Also, I've certainly gained some weight not all of which can be blamed on Covid, so I suspect my sag is too soft, I've found I bottom the fork and end up skipping the front tire under hard breaking, which is not a great sensation mid corner.
N4teTheGreat is offline   Reply With Quote
Old 11-13-2020, 02:19 PM   #10
The Temptations of Christ
PorradaVFR's Avatar

Join Date: Oct 2004
Location: Santa Clara, CA
Motorcycles: 2004 Honda VFR 800A, 2008 Ducati Hypermotard S (sold), 2004 Honda VFR 800 (RIP) :(
Just had my fork oil changed - it’s a maintenance item every ~18-24 months for casual street riders and the different is always notable. While my bike has limited adjustment I had Dave Moss adjust it and you can easily feel it when turning in and when on irregular pavement.

If you don’t remember or have never changed the fork oil (and in my case changed springs that align to your weight) you’re not getting all the bike you paid for. Do it and be aware the first time you brake and it feels like your front end is WAY firmer.
"Mgrush Fernran Grrable Mrgsush" - RRITTERSON

"I don't think anyone should ever take my advice." - KILLAKEYES
Witty comment. [citation needed]
PorradaVFR is offline   Reply With Quote
Old 11-13-2020, 09:23 PM   #11
Frisco's Avatar
Contributor +

Join Date: Nov 2005
Location: El Cerrito
Motorcycles: Yammies Ď17 FZ-09 and '13 FJR
Name: Carl
Great stories and insights!

ThinkFast - canít wait to hear your street setup story.
Frisco is offline   Reply With Quote
Old 11-14-2020, 03:55 PM   #12
Mr. Dual Sport Rider
ScottRNelson's Avatar
Founding Member

Join Date: Aug 2002
Location: Meridian, ID
Motorcycles: Honda XR650L, KTM 790 Adv R
Name: =Username
I've had Phil Douglas (Aftershocks Suspension) adjust the suspension on four bikes. I was amazed at how he could bounce a bike up and down a few times and know how to adjust it.

He definitely fixed an issue I had with my Ducati ST2. It tended to work its way to the outside of a bumpy corner. After he adjusted it the bike held the line well in the same corner. I had him do my 888 SPO too, but couldn't really tell any difference. He did my XR650L for a twenty buck donation at one of those Livermore Police events. That helped balance the front and rear. I am still using the same settings many years later.

Unless the suspension is way off, I can't tell what it needs. My KTM 790 Adv R has all kinds of adjustments available, but I'm happy with how it behaves both on twisty roads and off road, so I'm not touching it.
Scott R. Nelson - Meridian, Idaho (after 30 years in the Bay Area)
ScottRNelson is offline   Reply With Quote
Old 11-14-2020, 06:14 PM   #13
dtrides's Avatar
Contributor ++++ + + + + 4%

Join Date: Jun 2004
Location: St Helena, Ca.
Motorcycles: Aprilia Tuono Factory for the street, Sv 650s for the track
Name: Duncan
Carl...2021 MT 09 SP....nuff said..
AFM 989
dtrides is offline   Reply With Quote
Old 11-14-2020, 07:40 PM   #14
Frisco's Avatar
Contributor +

Join Date: Nov 2005
Location: El Cerrito
Motorcycles: Yammies Ď17 FZ-09 and '13 FJR
Name: Carl
Originally Posted by dtrides View Post
Carl...2021 MT 09 SP....nuff said..
Progressive forks, Penske, tons of Woodcraft, .... I already have one! 😂

Seriously though, Iím interested in checking it out. Not sure about the new style, more ccs is nice, but maybe itís just to compensate for more restrictive emissions.

Duncan, your in my neck of the woods now, letís get out for a ride!
Frisco is offline   Reply With Quote
Old 11-14-2020, 08:04 PM   #15
dtrides's Avatar
Contributor ++++ + + + + 4%

Join Date: Jun 2004
Location: St Helena, Ca.
Motorcycles: Aprilia Tuono Factory for the street, Sv 650s for the track
Name: Duncan
I would like to get together when ever the time is right.
I too would like to have some seat time on the new 900 SP ( as well as the Aprilia RS 660!)...
The bikes just keep getting better! Lucky us.
AFM 989
dtrides is offline   Reply With Quote

Thread Tools
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 Off

Forum Jump

All times are GMT -8. The time now is 01:21 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.