Gravely 34Z...10 inch tires won't fit?

Discussion in 'Lawn Mowing' started by hackitdown, Jun 14, 2011.

  1. hackitdown

    hackitdown LawnSite Silver Member
    Posts: 2,515

    I have a Gravely 34Z with stock tires (7.5"?) and rims, and really terrible traction on hills. I researched here on lawnsite regarding the traction problems, and several guys suggested Turfmaster 20-10-10 tires. The guys said they mounted them on the stock rims, and that helped the traction issue. So I ordered a set.

    When I brought the tires to my mechanic to be mounted, he says they won't fit on the rims. I have to say, they do look way too wide for the rims. Is he wrong? Does my machine have smaller rims than most? And it is hard to visualize those huge tires fitting in the wheel well area of the Gravely.

    Will they fit? Do I need new rims?

    Any help would be greatly appreciated. Thanks very much.
     
  2. topsites

    topsites LawnSite Fanatic
    Posts: 21,653

    Well gosh if your machine currently has 7.5" tires doesn't it stand to reason that the rims are made for that size tire?

    I mean I am sorry but you know, you can fit some off-size tires on a rim but to a point, for example...
    Assuming your rim is made for 7.5"s, you can probably fit anything from a 7" to an 8" on there
    and you might be able to spread out as far as 6.5" to 8.5"...
    Maybe, safely you can fit 7" to 8" and no more, that's assuming the rim is made for 7.5"s but certainly no more than an inch either way.

    Then...
    Lets just say we're already at the far end of the spread now, which is highly unusual because machine manufacturers
    tend to stay within certain parameters rather than to the edge, but lets just assume that the 7.5" on there was on the
    very low end rather than middle of the road (meaning the rim was actually made for an 8.5")...
    It's a stretch...
    But in that case one MIGHT get up to 9.5" on there but nothing smaller than a 7.5" and yet it still
    would be one heck of a gamble to think that anything much past 8" would fit.

    The next problem we run into, with folks fitting off-size tires on a rim, is later down the road the half
    won't know (or just as well can't remember) what size tire the rim was made for.

    But your mechanic is right, a 10" no way.
    You'd need new rims.
     
    Last edited: Jun 14, 2011
  3. hackitdown

    hackitdown LawnSite Silver Member
    Posts: 2,515

    Well gosh, yes.

    As I said in the original post, several Lawnsite members said that they mounted 20-10-10 tires on the stock rims. Guessing and estimating is fine, and thanks very much, but can someone with actual experience with this clarify?
     
  4. topsites

    topsites LawnSite Fanatic
    Posts: 21,653

    I was hoping my not needing a mechanic to mount my tires would be experience enough,
    but can you tell us where you saw LS members talk about fitting those 10" tires on your mower?
     
  5. hackitdown

    hackitdown LawnSite Silver Member
    Posts: 2,515

    Thanks for your help? These are the posts from guys with the same mower, that bought the same tires.

    http://www.lawnsite.com/showthread.php?t=345113&highlight=gravely+tires

    http://www.lawnsite.com/showthread.php?t=338927&highlight=gravely+tires&page=2

    http://www.lawnsite.com/showthread.php?t=339582&highlight=gravely+tires&page=3
     
  6. nolanjim

    nolanjim LawnSite Member
    Posts: 192

    What is the tire size on your old tires. I had a 34z, great machine. The rims were 10inches, I think we upgraded though.
    Posted via Mobile Device
     
  7. hackitdown

    hackitdown LawnSite Silver Member
    Posts: 2,515

    The old tires are 21-7.00-10. The stock wheels are 10x6.
     
  8. nolanjim

    nolanjim LawnSite Member
    Posts: 192

    Measure distance from tire to wheel well, if more than 1.5", it should fit. Others tried it and it worked just ask your mechanic to mount them.
    Posted via Mobile Device
     
  9. norwoodj

    norwoodj LawnSite Member
    Posts: 11

    we have one and i believe they were a 10 wide tire i put on it. flip the rims so there is more offset to the outside. that is what i did on mine and put valve stem on the otherside then you can still fill them easy.
     
  10. hackitdown

    hackitdown LawnSite Silver Member
    Posts: 2,515

    Update: I wrestled the 10" tires onto the 6" rims with my old motorcycle tire irons and soap, it took a while. The mechanic was wrong, they fit on, and I was able to fill them. The new tires rubbed against the frame a little, so I went to the autoparts store and bought spacers. The wheels/tires are back on the mower, but now because I used the spacers, the studs are a little short, you can see a couple of threads on the inside of the lugnut. Maybe longer studs will be the last piece of the puzzle. But how do you remove the old studs? The back side has no "nut" on which to put a wrench, it is rounded.
     

Share This Page