I have a few suspension setting questions and I know it's not a monster but I used to have one and I trust the opinions here. So I took my bike into the dealer to have them check out the alignment etc because it felt like it was pulling left and they found nothing wrong but noticed that the guy who set up the suspension for my weight had backed off the pre-load all the way to get my sag correct. So my dealer told me that I needed to revalve the front forks to have a better setup. Well I thought about it and if the pre-load has been backed off all the way for my weight than I need lighter springs and not a revalve. Sure enough I look up the spring rates on racetech.com and I see this.
Stock Front Forks = .960 kg/mm with a suggested rate of .875 kg/mm at my weight (160lb).
Stock Rear Spring = 8.7 kg/mm with a suggested rate of 7.10 kg/mm at my weight (160lb).
So now my question is which springs I should get. They have .85 or .9 for the front so I'm in the middle of those and for the rear spring they have 8.0 as the lowest. Any suggestions on what to do? This is a street bike only for the time and probably won't see any tracktime as I have another bike for that. I'm thinking go softer on the front and get a custom spring for the rear as it's not much more expensive.
Any suggestions are welcome and if I'm headed in the wrong direction with getting new springs instead of a revalve please let me know. Thanks in advance.
if you ride on some rough roads. i think a softer spring would fit you better. I have something stiffer than normal, and its not to good when the road gets bumpy. it feels like theres barely any absorption and it throws the bike around cause its so stiff. But its great on the corners.
As always the correct spring will ride best.
You should try the Ohlins site.
They may have the right spring for you.
I know that ducvet just sprung and valved an 848 shock so he knows the spring length and may be able to help you.
He's a sponsor.
Quote from: He Man on August 28, 2009, 04:22:18 PM
if you ride on some rough roads. i think a softer spring would fit you better. I have something stiffer than normal, and its not to good when the road gets bumpy. it feels like theres barely any absorption and it throws the bike around cause its so stiff. But its great on the corners.
I agree, if you are between 2 springs, go with the softer one.
BTW I really don't think that just backing off the preload all the way will make the bike behave as you are describing. Has to be something else.
The guy that set-up the suspension for me mentioned that I would be too light for the springs and said he would set it up the best he could for my weight, I just didn't realise that I was about 40-50 pounds too light. Playing with racetech's spring calculator to get the stock springs to be the recommended springs for street use you would need to weigh like 215 lbs.
With the preload backed off all the way I'm just sitting at the top of the spring stroke and if I can't get the spring to compress much it's going to be a rough ride. It's pretty bad, if I'm not careful paying attention to the road and hit something like a pothole or something there's a chance I could be bucked off the bike.
So I think I will go with the softer spring on the front and then get a custom rate spring on the rear shock then do the re-valving if I need to. Don't want to change too many things at once to find I don't like it.
Got some new info about my bike's suspension, don't know if anyone really cares considering it's an 848 but whatever.
The rear spring is physically too long to work for my weight. Even with the preload backed off all the way it still has too much preload for a 160 lb rider. The fix was putting an Ohlins shock into it which fits and is about an inch to inch and half shorter in length.
For the front I ordered new springs for as well and went with the .90. My local shop still tells me the springs are ok and that the problem with the 848's is that their valving is so large that you blow through it too quickly. So they still recommend a revalve which doesn't make sense to me because if I can't compress the spring how would revalving change that?
848's are sprung very stiff on the rear, I can believe that the OEM spring would be right for a 215# rider.
Not sure about the front springs, they seem to be more realistic in my limited experience.