315-345/20 Tire (rear) with Bilstein Shock ????

    Getting ready to order a 315 or 345/20 tire for rear of 2016 SS. Bought one way adjustable Bilstein shocks in group buy back in 2016. Shock is mounted upside down so that it can be adjusted if necessary. Curious if anyone is running a 315 or 345/20 tire with that shock? Have seen on the forum that there may be issues with the Bilstein shock and these size tires.
    Thanks for info....

    I have found the manufacture of tire also makes a difference, I have the JRI 2 way my 335 michelin pilot super sport did not fit, while a 345 Toyo T1r does fit with the same shocks. Just something to keep in mind. I am having to run a 5mil spacer right now to ensure it does not rub.


    Matthew

    My understanding is that the normal Bilstein shocks are just fine for both sizes.

    The Polaris Belstein shocks will NOT work with a 345 rear tire. I would guess 315 should be fine though.

    Owner of Slingshot #263 that has some stock parts left on it. :D

    345 definitely does not work with the Polaris 10 way adjustable shocks. Not sure how wide the spring is on the one way. Best bet is to measure the width of a stock shock spring and then yours. That way you can judge the space.

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    Quote from SlingRider

    345 definitely does not work with the Polaris 10 way adjustable shocks. Not sure how wide the spring is on the one way. Best bet is to measure the width of a stock shock spring and then yours. That way you can judge the space.


    I was thinking 10 way adjustable was a misprint somehow. Could anyone tell me the ten ways it's adjustable?



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    Huh, I was running a 345 (Michelin Pilot Super Sport) with JRI shocks with no problem. I traded in that Sling for another and did not swap those shocks over this time. I ordered the Hahn QA1's 2-way adjustable. I hope there is nor problems. I have been running a 345 since Feb 2015 with a Toyo and now a Michelin. I am wondering if the wheel manufacturer has anything to do with it? I bought the package from Roaring Toyz with no problems at all for over 30k miles.

    Based upon my limited mechanical and measuring skills here is what I eyeball on shocks:


    Stock rear (uncompressed) - 4" wide, cylinder to outside of spring 1", cylinder 2".


    Bilstein rear (mounted) - 3 1/2" wide, cylinder to outside of spring 1/2", cylinder 2".
    (springs appear to be thicker)


    Currently running a 305/25/22 rear tire. Going to switch to 20" and probably a 315 Toyo T1R.

    Quote from MiM

    Interested in you reporting back about the jris versus qa1s @Tim0341...


    Which jris did you have and why the switch?

    My JRI's were red and I bought the SLR Orange Madness. I didn't want the hassle of having to take the springs to get powered coated orange. Also wanted to try a different shock and Hahn's seems like a good deal. Looking forward to only 15 (I think) adjustments instead of 72!!

    I run those on the front of mine for track days.

    Great tire for the front, but NOT the back. They are crazy asymmetrical and wont perform and wear correctly centered on the rear of the Slingshot.

    Also, I would not get caught driving in the cold (below 45 degrees) or rain on Toyo R888 or Toyo R888r tires.

    These are warm weather track tires.

    Owner of Slingshot #263 that has some stock parts left on it. :D

    Here are pics of a 345 Toyo T1R on a 20X12 45mm offset wheel that does a good job in comparing the size difference of the stock shocks and the Alpha / JRi 2-way shocks.

    Stock


    JRi 2-Way shocks

    Owner of Slingshot #263 that has some stock parts left on it. :D

    Thanks for the pictures.....the 315 Toyo is actually 1.7" shorter OD than my current set up. My shock is upside down and should provide a little more space than yours. 345 is an 1" wider than 315. What air pressure are you running.

    You will have plenty of room. :)

    I run mine on the street around 25-26 psi on the rear around 28-30 on the front. Anywhere between 25-32 psi in good. The softer you run them, the more the vehicle likes to wander on cracks, lines, etc. But, you obviously get a little better grip at a lower PSI.

    Owner of Slingshot #263 that has some stock parts left on it. :D

    I can see your point with the asymmetry (unsure of anyone who has that type of rear tire to see the wear after 1,500 miles or so)... That said, I really haven't had an issue in the rain with the Proxes 888's (knock on wood)! As my tire gets slicker from wear (and if the temp drops a ton), I will be throwing one of these on back until spring.


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