| Author | Message | ||
     Bigbully67 |
I've got about 3k miles on my '09 cr now and have gotten pretty comfortable ridding it. It's been a long time since I've been on a street bike. My last bike was a new gpz750 to give you an idea just how long it's been, OK? Anyway, I'm having a blast and really starting to love this bike but have found the recommended suspension settings in the owners manual leave a lot to be desired. I've been down to PBIR in south Florida ,as a spectator, for a couple track days and would like to hit the track now. I want to learn as much as I can about suspension tuning first. I've searched for threads, read books and watched numerous videos trying to educate myself and still have some questions for you guys. Let me start with sag settings. After all my reading,it seems that 35mm sag up front and 25mm sag in the rear are good starting points for my bike. For me to get 35mm up front I have to run 0 preload. Is running no preload acceptable? Or should I be looking at getting lighter springs? I'm measuring sag with my compression damping 1.5 turns out. Should it be backed off to measure sag? I havn't read anywhere that damping will effect sag but it seems to me that it would. I was able to reach 25mm sag on the rear on the 2nd ramp setting so I think I,m good there. Sorry for such a long post. | ||
| Dannybuell |
IMHO sag is a place to start. I have added more preload because I don't like the front end dive that occurs with traditional sag settings. compression and rebound will not interfere with sag setup. set a zip tie on the fork. see how far it goes down during normal and or track riding. the general idea is that you should not be using all of your suspension travel. Additional preload makes suspension collapse a bit more difficult. compression fine tunes the nose dive and rebound follows by recovering and putting the suspension back to its neutral state quickly enough to not feel collapsed under you. Done properly the bike will be smooth enough to not feel vibration in the bars from an over compression setting, rebound recovery will be neither slow or so fast that it punishes the rider. hope this helps. | ||
| Skntpig |
No preload is fine if you are getting correct sag. Keep in mind the only way to know if your adjustments are working is to only adjust one setting and ride, reflect, readjust. Comp won't affect sag that much but it will affect how much travel you use as indicated by the zip tie trick. Once you get close even an 1/8 turn on a comp or reb screw will make a notable difference. When searching try nothing more than 1/4 or you might go past the correct setting. Try softer than the book first and tighten as you go. I bet you are under 175 lbs. | ||
| Bueller4ever |
I turn the front preload back a 1/4 inch, that's what all the pros say to do when it's set to zero. How much do you weigh? | ||
| Chameleon |
Best bet would be to pay a suspension pro to set it up for you. The $40 I spent on this service at the track was worth it. | ||
| Bigbully67 |
Thank you all for your replies. I weigh 165 with no gear. I have 1/4 inch turned in on the front preload to get me just shy of my 35mm goal. My rear is dead on my 25mm goal sitting on the # 2 ramp position. I followed the owners manuals recommendations on all of damping settings for a baseline to start with. After putting a zip tie on my fork I set out to hit what few twisties there are in my area of South Florida for the first time since changing my sag. I have chosen a route that is about 20 miles long with a wide variety of road surfaces from fresh smooth black top to old abused concrete roads that are all cracked and potholed. It also includes everything from high speed sweepers to some very tight and varying radius turns. I plan to stick to this same route for all of my suspension evaluations while taking good notes and making only one small adjustment at a time. Realizing that my -6 turns of preload up front and -1 notch of preload on the back would most likely make a huge difference in my bikes handling characteristics, I took it very easy on my first lap progressively pushing it harder over the next few laps too see what I was working with now. I can't even begin to put into words how much of an improvement was made just by setting the sag. My bike was transformed from a bone jarring pig that I had to force into a turn and fight throughout the radius to maintain my line to a machine that felt as though it could read my mind and obeyed my every input effortlessly. My tires remained firmly planted, it fell into turns and it tracked as if it were on rails. I can get on the gas much earlier and harder coming out of a turn, without sending my front end skyward, than I ever could of dreamed of before. I'm one vary happy Buelly! Now I have something I can work with. My bike handles so much better it is hard to put my finger on any area that needs to be worked on. After some thought, I think that it felt kind of "too smooth" over the smaller hard bumps and cracks. I don't know, maybe vague feedback would be a better way to put it. I would like to better feel whats going on under me. Does that make any sense? Any advice on how to achieve that would be appreciated. My guess is to slowly decrease compression damping on the forks. Am I on the rite track? After returning home I checked the zip tie and it shows I have 1.75 inches of unused travel.What should I be shooting for there? | ||
| Dannybuell |
The bond has started. Welcome! Loosen/Less rebound when it feels vague, collapsed, as you say 'whats going on under me'. They come up faster with less rebound. I like to get the compression to the point the handle bars vibrate and then I back off. 1.75 inches left makes me think you need more preload. up the rear one notch. Add fork preload slowly. with the ratchet pointing to 12 o' clock tighten to 1 o'clock (1/12 of a turn). test and retest. you will know when you have gone too far. take the wrench with you just in case you need an immediate adjustment. | ||
| Bueller4ever |
Did you do any hard stops or come down hard from some wheelies? Do a few stoppies and see if it still has 1.75 inches. If you look around the net, you'll see a few recommend 10mm of travel left as a safety net. That's only .4 inches. | ||
| Dannybuell |
.4 of an inch suspension travel left will not work for me. There is too much urban and winter decay with potholes that may or may not be resolved until springtime. Head on pothole and unavoidable? On your pegs and still definitely more than .4" needed though. No nose dive please: Catch a pothole in the middle of a turn and you can be braking hard standing the bike up a bit, and looking for a new line in less than a second. Not a good time to add an upset balance to the equation. | ||
| Bigbully67 |
Dannybuell- Since I had two comments on the amount of fork travel that remained unused, I'll work on that this morning and hold off on any damping adjustments. Will increasing preload as you described help increase fork travel? Can you explain,"you will know when you have gone too far", what should I be looking for? Bueller4ever- Everyone seems to agree that I could be utilizing more of my fork travel. Although I didn't do any stoppies, I did get the front off the ground and brake very hard. At what point should I be looking at getting lighter springs? It seems to me that might be a good thing to do. Am I wrong? Thanks for your help guys. I'm really starting to enjoy trying to figure out how this suspension really works. | ||
| Dannybuell |
Increased preload will give more resistance to travel. It will still travel but will take more energy to make it happen. You have gone too far with front preload, relative to the rear, when you are wrestling it into the turn. p.s. proper tire pressure is assumed. | ||
| J_copeland |
I set mine up per the manual and it's on rails.It feels even better than my Daytona 675. | ||
| Blake |
>>> Increased preload will give more resistance to travel. It will still travel but will take more energy to make it happen. That is a very common misperception. Preload only adjusts the ratio of travel between compression and rebound and as a result also the ride height. In fact, increasing preload will increase the volume of air within forks thus reducing the effective spring rate there. Not sure about the rear shock. Damping, oil level, oil viscosity, and spring rate (different springs) will affect the overall effective spring rate. | ||
| Blake |
>>> 1.75 inches left makes me think you need more preload. More preload would increase the amount of available and thus unused suspension travel and would alter the sag that has proven well-set per his riding observations. To gain more use of front compression travel you would do one or any combination of the following: a) decrease compression damping, b) reduce oil level, c) reduce oil viscosity d. install lower rate springs Hard braking over uneven pavement will best characterize the amount of actual compression travel at front forks. | ||
| Blake |
One further word of advice, before emergency arises, Danny ought to check to see if he put his skivvies on backwards this morning.  | ||
| Dannybuell |
Blake I am so sorry to read that you are thinking about me in my shorts. IDK what to say... no thanks. | ||
| Xtreme6669 |
IS 25/35 WHAT YOU GUYS WOULD RECOMMEND ON THESE BIKES FOR SAG? READING THRU SOME SUP ARTICLES IT SEEMS LIKE MOST REC. KEEPING THEM EVEN... AROUND 25 FOR THE TRACK AND 35 FOR THE STREET. | ||
| Green1 |
Try This as a place to start http://www.youtube.com/watch?v=rv8DY5Prl5c&feature =related | ||
| Xodot |
they have you on the right track 67 with good and clearly explained guidance. PTS | ||
| Blake |
Danny is a girl? Who knew? Sorry to confuse your gender there Danny. But Missy, before you give out any more advise on suspension tuning, maybe try learning the basic science of it. | ||
| Dannybuell |
Blake: LOL 2x. Posted on Thursday, November 11, 2010 - 01:00 pm: "In fact, increasing preload will increase the volume of air within forks thus reducing the effective spring rate there.". Spring steel does not respond to air. More air in the system means less valving potential, there could be oil taking its place. The 'air' you speak of may or may not be there. How would you know what quantity of oil I have in my forks? Posted on Thursday, November 11, 2010 - 01:26 pm:"To gain more use of front compression travel" ...its suspension travel silly boy. "a) decrease compression damping, " compression damping does not change suspension travel just the energy required to make it happen. I could go on. Bad day huh? No dog to kick? A couple of beers and you are ready to be an internet bully? When are you going to raise the bar on yourself? |
