1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Tire pressure

Discussion in 'Newbie Forum' started by WHCSC, May 18, 2012.

  1. WE0H

    WE0H Senior Member

    Joined:
    Mar 25, 2010
    3,247
    527
    0
    Location:
    Minnesota
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I have the MXM4 Michelin's in 17's on my car :) I am wondering if the pressure is way low or way high. Either that or they are real squirmy when new. I have less than 300 miles on my car. Only driven it 3 or 4 times so far ;)

    Mike


    iPhone :)
     
  2. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    19,011
    4,081
    50
    Location:
    Grass Valley, CA.
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I disagree with your reasoning for twitchy behavior. If if you stiffen the sidewall then the tire will be more responsive. That means it is more responsive to steering input as well as road-induced input.

    I have not experienced this issue with all 6 of the tires I've tried. It was only real noticeable with a few, my present AVID Ascends included. My GenIII just seems more twitchy and likely to trampling than my GenII. Even at 60psi my GenII with Integritys wasn't as twitchy as my GenIII with AVIDs at 48psi. :(
     
  3. tumbleweed

    tumbleweed Senior Member

    Joined:
    Oct 3, 2005
    4,067
    687
    0
    Location:
    Eastern Oregon
    Vehicle:
    2010 Prius
    Model:
    V
    Assuming you are correct, and assuming we have both driven long enough to tell twitchy from not twitchy, why do you and a few other Gen3 owners have this problem and most of us do not? I am not ready to chalk it up to tires or tire pressures yet. Are you using 215/45-17 tires on your Gen3?

    I noticed on another thread that all of the people reporting poor tracking were driving Prius II through IV versions and none of us with Prius V (five) had noticed it. Could it be that the different suspension components discovered by Thai, quicker steering ratio, and different steering motor of the Prius V make the car more stable?
     
  4. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    19,011
    4,081
    50
    Location:
    Grass Valley, CA.
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    My definition of twitchy is the car darts back and forth without any steering input. Steering input can exacerbate this issue. :)

    I do not notice this with the 215/45/17s. It is noticeable with the 195/65/15s, particularly the Ascends. I should try running higher pressure again now that they are fully broken in and see if the problem still exists.
     
  5. tumbleweed

    tumbleweed Senior Member

    Joined:
    Oct 3, 2005
    4,067
    687
    0
    Location:
    Eastern Oregon
    Vehicle:
    2010 Prius
    Model:
    V
    Be sure you post how that works out. This, for me at least, is an interesting problem and it crops up from time to time on here. I know from my Gen2 that it can be frustrating and even dangerous so it would be nice if we could pin it down.
     
  6. F8L

    F8L Protecting Habitat & AG Lands

    Joined:
    Aug 14, 2006
    19,011
    4,081
    50
    Location:
    Grass Valley, CA.
    Vehicle:
    Other Non-Hybrid
    Model:
    N/A
    I will once I swap back to the 15s. :) FWIW the twitching is gone at 44psi and the tires broken in.