I have been feeling what I would describe as a loose front end. It is apparently only noticeable to me. I think we are all in tune with our bikes such that we know when something 'just is not right'. I had an experienced rider take it for a spin, and he did not feel what I described. His suggestion was to back off my steering damper, which I did. The looseness is still there. I have been checking everything I can think of, to no avail. Yesterday, I took a passenger on a ride that ranged from block to block city riding to faster freeway riding. Putting a passenger on the back completely eliminated the loose feeling. The front end felt rock solid. There was no twitchiness. As soon as she got off the bike, it was back. This makes me think I have the suspension set wrong. Before I start jacking with it, does anyone have any suggestions where I should start? I set the suspension by the chart in the owner's manual for my weight with gear. I did this two years ago, and have not touched it since. I know to adjust one thing at a time and document the changes. I just don't know that much about the settings. I'm thinking less compression and rebound damping?
Thanks everyone. The video basically says to follow the manual. I have done that already. The damper is turned down to its lowest setting. It was acting this way before the damper was installed. I check my tire pressure before EVERY ride. I tried bumping the pressure up two pounds in each tire, but it made no difference. They now ride at the owner manual specs. 36 rear, 34 front, cold pressure. I am thinking I need to adjust the suspension by the manual's chart for a slightly lighter weight rider.
Front------------ Does it nose dive when you hit the brakes, or fall into a low speed turn a little too easily? Increase preload. After preload sweet spot for your riding style, adjust compression to match.
Does the front end go down and stay down, not recover or come back fast enough? less rebound.
Rear-------------
Does the bike understeer, lose the line and fall out of the turn? Increase preload After preload sweet spot is found adjust compression to match.
Does the rear bottom out? Increase preload, compression.
Does the seat come back so quickly that it spanks you after a big bump? Increase rebound.
These are good questions. I have the stock size Pirrelli Diablo Rosso Corsas with low miles. I know about the zip tie trick. I have no idea how much it should compress. The person who test rode my bike is lighter than me by quite a bit, I imagine. I would think it would make the 'loosness' more noticeable, but the steering damper was the biggest thing he noticed. Mine was cranked up tighter than his by a long shot. Actually, I'm not sure if his street bike had a damper, maybe just his race bike. I took his street bike for a short ride as a comparison. He had changed the height of his forks in the upper clamp. I liked my stock geometry better. As far as my weight, I'd say I'm somewhere in the middle. I'm not laying on the air box, but I'm not sitting straight up, either. My triple clamp is at the stock height. I have already checked the steering head bearing and re-torqued it. All is good there. My wheel bearings were good when I changed tires recently.
Danny, your questions have me thinking. When I'm running at a spirited pace entering curves, I often have to apply more throttle as the bike wants to go to the inside. It won't settle till I push it harder. I have never bottomed out the suspension. In fact, even putting a passenger on the back, it barely sagged. The seat does not spank on bumps. I'm going to play with the adjustments next Saturday. My bike is a weekend toy. I'll let y'all know what I find. Thanks for all the suggestions!
as has been noted in other threads, the book settings are not the best.
try (since you have nothing to loose and it's fun) setting your compression to full soft (no dampening) with the minimum rebound dampening. I did this and found a huge difference and then dialed in both settings 1/4 turn at a time until I got it where I liked it. This may be a fast cheap and simple solution to your problem.
Since you say you are inexperienced with suspension settings it also allows you to feel what more and less dampening on compression and rebound does and this is important knowledge to have in your pocket.
From your profile it looks as if you have an 08 model - some of the handbooks had the wrong suspension settings in them. there will probably be the corrected settings posted on here somewhere, do a search.
The handbooks that were linked to from here have now gone.
Just a guess, I'd go after the initial preload first, it sounds like you've got it set too stiff. Adding a passenger settled it down, so there's your best indicator of the preload being set too high.
I did this two years ago, and have not touched it since.
Assume you have not serviced the forks or shock since you initially set it up. Setting will fall out of adjustment as time passes due to the contamination of the oil. Tends to get thicker which means the tendency would be for increased damping if you never mess with the adjustments, hence if you were to make minute adjustments to counteract the dirty oil you would tend to decrease damping as time goes on...
But don't forget about ambient temps too. Those will have an effect on the damping effects as well. It's definitely moving target and I wish I was better at it.
I am willing to bet your a "lighter" rider, 150? 160 lbs maybe? If I'm right, back the front preload all the way out then turn it in 1/4 to a 1/2 turn. You'll probably get a sag number of about 25 or 26 mm, which is still too little (at least for me), but this is the closest you'll get without replacing the springs. Others here in my weight range have claimed to get better sag values and I can't explain that. I've done the measurements myself and by a pro, and our numbers were in agreement.
After your sag is close, then play with compression and rebound damping.
Is there a given value for proper sag adjustment? Is it 25 or 26 mm? How does that work? I know to put a tie wrap on the front forks. Do you just sit on it, or go for a ride to knock the tie wrap down for the measurement? Do you need to give the bike a good hard brake to dive the front end? What about the back end? How do you figure that? Thanks for all the advice everyone!
You do your testing and tuning with the tie wrap. Some of the racers on this site have said that you only want to use 80% of your suspension travel. I see the argument of keeping the other 20% in reserve as prudent. Zip tie up and standing as though you were about to mount, grab the bars and bounce the daylights out of the front forks to get an idea of the forks range of motion. Pull your zip tie up and ride/test/tune with the goal of tuning preload until your riding style saves 20% of the forks range of motion from test one.
Ride your bike out to the CMRA races at ECR this weekend and have Jimmy Cambora push on it for you. He's the best tuner around.
Roger Albert will also be there, and he's excellent with suspension and chassis as well. Roger does a full sag set up with you on the bike incl measurements and a data sheet for something like $40. It's worth it.
If you come out Saturday, I'll be putting final touches on the race bike for Sunday's sprints. We will have the grill going, wife will be there, and a couple of buds hanging out. Mini endurance races Saturday, and a bit of sprint practice late in the day.
Jdugger, I would LOVE to come get my ride set up by a pro. I would also enjoy hanging out watching the fun. I just can't do it this Saturday. I have other commitments. Will they still be there Sunday? I'm not worried about the heat.
Yea, those guys will be there Sunday. Come by and I'll introduce you.
Sunday will be a fun day to hang around, too, and actually, the racing will be more fun to watch because it's sprints, but I'll be a little more preoccupied with my own issues of getting my head in the game and growing a pair to find that 3-4 seconds I've lost since last October.
I'll be sprint racing in at least 2, but maybe 4 races depending on what tires I buy! Several of my buds are racing, including a fast Prov Nov you may have met before. Just come down by the garage.
Race weekends are a lot of fun, so definitely come and hang out.