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suspension setup to duplicate tire psi

Discussion in 'Technical and Troubleshooting Torque' started by Traviss, Dec 4, 2008.

  1. I would like to know what suspension setup or what part of the suspension do you adjust to duplicate tire presures ..
    E.G : I like lower tire presures 30-32 front and 34-36 rear but it wears the tires quickly so I dont do it ,But the ride is harder more rigid and I have less feel ..
    I have the bike on factory setting and Im about to start playing ,Im happy with the factory setting once I drop tire presures ...So instead of ride adjust ,ride adjust etc etc I was wondering what to adjust to simulate what Im happy with ..
    And its a CBR1000rr 07

  2. If the ride is too stiff you need to look at backing of the damping.
  3. Mate, this could get real interesting as its such a personal thing and tyre preference comes into it too.
    I'd rather softer suspension on higher PSI otherwise the steering is to "doughy".
    But for what you're asking softer compression and maybe slower rebound as well.
    You have a fair bit of "local" help available for the blade.
  4. I have a few books on set up but nothing is covered about tire presures and I really like the way it worked on the last tires and the presure I was running and to be truthful I couldnt be stuffed doing the ride adjust ride adjust thing as I just wont to ride it ,when I get the chance ...The owners manual says Harder for rough roads ??? Im thinking of one click everything Harder and see but I would still like to know how to duplicte what Ive done with PSI...
  5. As far as I know, regardless of tire pressures the suspension should be setup for your weight and riding style first of all. You said that the bike is still on factory settings. Im not trying to shoot your idea down but imho you are getting way ahead of yourself in trying to setup the suspension to suit a relatively minor tire pressure change. For the majority of riders this sort of setup is more advanced, I think you should focus on setting up just for your weight + style first.
  6. I understand what Travis is trying to achieve. I've seen him ride (before he's out of sight) :oops: and I suspect the blade is almost right for weight/style/roads at stock settings.

    Travis - if the books don't cover it you are most likely going to have to do test after test on the Dargo Rd I suspect. Have you had a chat to Joe or spock?

    Post it on TM too.
  7. The factory setting are perfect for my weight but the drop in tire presures made it feel even better So thats why Im asking how to duplicate it into set up so i dont wear the tire any quicker ..The standard setting plus 30-36psi felt great But I done this because the tires (briggies) started feeling very washy as they wore down .Now I have new rubber and want the same feeling without dropping psi ,if that makes sence..
  8. I will do that tonight Chriss.. I was hoping some of the race guys here might have the answers or a calculation as how its done ..
  9. There is no calculation for it. Set the tyre pressures back to where they should be.

    As has been said before you have to tune your damping. Whaen does the bike feel harsh. Is it uniformly so or the front harsher than the rear etc?

    Does the bike drop into depressions or does it try to launch you skywards when you hit a bump?

    These are fundamental observations to make before messing around with the settings so that you head in the right direction. Once the suspension is correctly setup you will experience more control and better tyre life.

    Just remember though, the suspension is there to keep the tyre in contact with the road. Comfort is secondary.
  10. TP ...It feels less planted or slippery with the tire presures at 36-42 and it feels like its on rails at 30-36 I will play with dampening if I have to but as Im road riding and not out on the track it makes it harder to find what Im looking for ,that lower tire presure are all ready giving me at a cost..i might harden everything 1 notch and see how it goes except springs .
    What I was looking for was a 1 psi is equal to 1 notch hard or soft dampening or rebound or both ...
  11. Unfortunately no such calculation exists.

    What you're doing by lowering the tyre pressures is altering not only the profile of the tyre, but also how it moulds into the road. That's not something that directly correlates to a suspension setting.

    Grip vs Longevity is always a balance.

    Also remember that a tyre manufacturer recommends a pressure based on a number of factors. One of them is how the tyre changes profile at its operating temperature. If you lower the tyre pressure too much and the tyre doesn't get to a good temperature, it won't get to the correct profile. And so on.

    Also don't assume that making suspension 'harder' will improve the grip or have the bike behave in the manner you expect. Depending on your weight, your riding style and the conditions under which you ride, you might want to change preload, compression and damping (either +/-)
  12. No calculation ...Not what I wanted to hear...Guess Im taking a screw driver on me next ride..
  13. Find a bit of raod nearby that has a wide range or surface irregularities, things like the odd dip, bump, hole etc. Ride over them and take note of what you feel the bike is doing.

    First thing is to set your spring preload correctly and go from there. Typically the suspension should settle 25mm at the front and about 20mm at the rear (unless you're tracking it).

    Once that is done, go for your little ride. Observe, then do it again to see if you observations were correct. When changing settings, do one at a time and note what the change was so you don't get lost.

    If the bike is dropping into holes then you need to reduce the rebound damping, if it is trying to shoot you out of the seat when you hit a bump, reduce the compression damping. Do the adjustments progressively, ie. a couple of clicks or 1/2 a turn at a time. Ride the same road again at the same speed and see if it is better.

    It takes time to get right but it is worth it.
  14. And the beauty of this is that being shot out of the seat could also be too quick rebound....

    Don't think 'Hard' and 'Soft', think 'Quick' and 'Slow'
  15. Would be intresting to find out the pressure variance from a cold to a hot tyre. 32psi & 36psi might fall within this range.

    AlthoughI didn't think a change in tyre pressure would have that great an impact to tyre wear on a 1000cc sportsbike.
  16. lower presures gives you a larger contact patch ,so more wear in the corners and under brakes and the presure increase on road riding is lucky to be 1-2 psi ..
  17. Your making the tire presure drop sound a hell of alot easyer ,I guess I will have to do it the old fashioned way ,My mission of the easy out looks doomed ...You can see my delema 2 sec with a tire gauge and its perfect or a good couple of hours a spanner and a flat head and a quiet peice of road to maybe get the same effect...
  18. It won't be the same effect though. Running with the tyres underinflated is dangerous as well as bad for wear. Without correct inflation you are more prone to aquaplaning as the tyre cannot disperse water as it is designed, your steering and braking can be compromised and with the state of roads in this country, your chances of damaging a rim if you hit a hole are fairly significant.
  19. I am only talking about a 4-6 psi drop max cold tires so around the 32-38 range ,I dont think this is low enough to cause rim damage and it still changes direction quickly and smoothly ..
  20. They probably are less planted and more slippery as the higher pressure means a smaller contact patch. I can't see how changing suspension settings will make any difference to grip though. :? All it will mean is that you get softer suspension on tyres that have less grip. I'm not a suspension expert but I'm fairly sure you've mixed up the cushioning effect of softer tyres with the grip effect of softer tyres. Suspension adjustments can give you the cushioning, but I don't think it'll help with grip.

    For the increase in tyre life you'd get with a 4psi increase, I doubt it's worth all the effort. It sounds like you're riding hard enough that tyres quickly die anyway, so you might be best stick with what works and enjoy it. :)