[Blakey]

Im looking to put 31X10.5 -23 on my 2005 Jimny, iv cut all the guards already, and extended them for the width, just wondering if anyone else has put this size and offset or around it on a Jimny before as im just wondering on clearances on the offset.

The Tyres im looking at getting are Insa Turbo Sahara or Special Tracks, failing them i dunno.

31X10.5 are they actually 31" dia and 10.5" wide? or physically smaller then that.

Or should i go 30X9.5 at the -23 offset

iv already done chopping of the guards so if i need to do any hammering of other parts as well as well i don't have a problem with it, and ill probably be removing the stock front tiedown points if i can as its pretty in the way from what i can see.

and i know of the extra stresses that are involved with pushing the wheels out, this is not my daily driver just a play car but i will be getting it engineered to be road legal.

if your after other specs of the Jimny it has a full 3inch lift castor corrected front and rear radius arms, HD panhards, uprated 3" springs, rough country shocks to suit lift, extended brake lines, it also has defender arches modified to suit, so i know the arches will clear the wheels easily its just the other parts that I'm unsure of.

Future mods will be HD steering and tierod arms and brake upgrade, as well as swapping to Sierra Transfer and installing a front locker, and Uprated axles and CV's after they break

[Aaron]

Hey mate I'm not 100% sure wheather they will fit or not but 1 thing you will have to consider is gearing. Those size tyres on stock gearing won't be very pleasurable. A popular modification is the Sierra transfer case, I would search it for you but I'm on my phone. You could also consider putting reduction gears in your jimmy case.

[SierraDan]

with a -23 offset im assuming you're looking at an 8" rim.
10.5" tyres suck on 8" rims.

[Blakey]

SierraDan wrote:

with a -23 offset im assuming you're looking at an 8" rim.
10.5" tyres suck on 8" rims.

how so what does that cause? and yes i was going to go 8" rim

[zooky08]

You will find it's going to be hard to get it road legal in qld. You may find some one willing to engineer it though.

[31zook]

15x8s on 235s are worse...

[matfan]

I have 31x10.5 on 8 inch rims and no complaints from me

[SierraDan]

Blakey wrote:

SierraDan wrote:

with a -23 offset im assuming you're looking at an 8" rim.
10.5" tyres suck on 8" rims.

how so what does that cause? and yes i was going to go 8" rim

When you air down to a useable pressure the tyre isn't on the bead as strong as it could be on a 7" rim.
So losing a bead is more likely. And mud/dirt in the bead is inevitable.

[Blakey]

to clear the stock tiedown point i need that -23 when at full lock, but i also with that i only just nick the inner panel seam of the inner engine guard panel where the panel just infront of the door meets inside the guard, i can hammer that seam flat to give me about 10mm clearance when at full lock other then that i cant see anything else that will hit unless someone knows of common places for the tyres to scrub in jimnys when going bigger tyres.

I made a mock up tyre out of wood lol dunno how accurate it is, but made a 31" plank of MDF then put a 10.5" Piece on top at the appropriate offset from center. but i cant flex it up like that

and @SierraDan i have seen the same thing happen on a 7" rim to my mates hulux. with 31X10.5 tyre, but thanks for letting me know. but that also depends on the tyre, some are better then others at different widths when at lower pressures.

[SierraDan]

Seems jimny drivers run -13 15x7

[GRPABT1]

I've got a set of 15X8's in negative 23 that I'm selling as I was sick of leaking beads and rolling tyres off the rim. I went for a set of custom offset 15x7's to match the track width of the 15X8-23's. 15x7 in -40mm will give the relatively the same tyre positioning but a much tighter bead. PM fatzook or offroad solutions off here regarding a set of custom offset rims, you will be much happier in the long run I think. -13 15X7's will give the same distance from the inner guard but you lose out on track width, -40mm should help keep the tyre off the inner guard a little bit also but you will lose some scrub radius.

[Blakey]

This is where i hit when at full lock on this offset as shown by my wood template



and this is the overall look


if you think its better to go a smaller negative offset ill just remove the stock tie down points to easily clear everything. im just trying to get more width cause of the height increase.

and @ GRPABT1 wouldn't going to -40 make it stick out another 17mm, the way i see it the Tyre is center to the rim no matter what rim you use, so changing from 8" to 7" shouldn't make the Tyre move at the same offset, or am i getting this offset thing all wrong. so even getting a 7" rim at -23 offset the Tyre will be in the same place as the 8" rim at -23 offset,

[monley]

I have run 15x7 -13 with 1" spacers and 31s. Hammered the firewall and seem, done. I've got a set of 15x8s -24 rims going on thus week. I won't gave rubbing. BTW that's with stock arms

[SierraDan]

A smaller offset isn't what we're saying. A smaller rim width. Then an offset to suit your needs.

[GRPABT1]

Blakey wrote:

and @ GRPABT1 wouldn't going to -40 make it stick out another 17mm, the way i see it the Tyre is center to the rim no matter what rim you use, so changing from 8" to 7" shouldn't make the Tyre move at the same offset, or am i getting this offset thing all wrong. so even getting a 7" rim at -23 offset the Tyre will be in the same place as the 8" rim at -23 offset,

Yes you have this offset thing all wrong. the number -23 is a measurement in mm that the mounting surface is from the centre line of the rim. So an 8" rim has a centreline 4" from each edge of the rim and a 7" rim has 3.5" from the centreline to the edge. So the same offset on different width rims has different distances from the mounting surface to the edge of the rim.

So for example an 8" rim with -24 (round that 24mm off to an inch) has 3 inches from the wheel mounting surface towards the inner guard and 5 inches sticking out. A 7" rim with -24 will have 2.5" towards the inner guard and only 4.5" sticking out. So whilst you gain some more inner guard clearance with the same offset on a smaller rim you will still lose some overall track width. My suggestion of 15X7" rims in -40mm works out to give you about the same overall track width and an extra inch or so inner guard clearance as a 15X8 -24. capish?

[Blakey]

GRPABT1 wrote:

Blakey wrote:

and @ GRPABT1 wouldn't going to -40 make it stick out another 17mm, the way i see it the Tyre is center to the rim no matter what rim you use, so changing from 8" to 7" shouldn't make the Tyre move at the same offset, or am i getting this offset thing all wrong. so even getting a 7" rim at -23 offset the Tyre will be in the same place as the 8" rim at -23 offset,

Yes you have this offset thing all wrong. the number -23 is a measurement in mm that the mounting surface is from the centre line of the rim. So an 8" rim has a centreline 4" from each edge of the rim and a 7" rim has 3.5" from the centreline to the edge. So the same offset on different width rims has different distances from the mounting surface to the edge of the rim.

So for example an 8" rim with -24 (round that 24mm off to an inch) has 3 inches from the wheel mounting surface towards the inner guard and 5 inches sticking out. A 7" rim with -24 will have 2.5" towards the inner guard and only 4.5" sticking out. So whilst you gain some more inner guard clearance with the same offset on a smaller rim you will still lose some overall track width. My suggestion of 15X7" rims in -40mm works out to give you about the same overall track width and an extra inch or so inner guard clearance as a 15X8 -24. capish?

its not the rim that hitting anything its the tyre, the tyre is always central to the rim, so if i have a 7" rim or a 8" rim the tyre will always be central to it. so if i had the same offset on each the tyre would be in the exact same spot as the tyre doesn't get smaller with a smaller rim.

also its outer clearance that i have issues, as its the outside of the tyre that hits that lip. when at full lock

and @ Monley is that picture the same place im hitting at full lock? also i have Castor corrected arms so i would of thought mine would be further forward, maybe my mockup wood is to big. are 31" tyres truly 31" what tyres are you running atm Monley like brand and model.

[monley]

31x10.5 on a 7" rim. They are general grabber at2. I had 15x8- 13 and the tyres use to hit the coil tower. I have a set of 15x8 -24 with my procomp 31s going back on tonight to fix this issue. If I had castor corrected arms, the tyre would hit the head light bucket.

[SierraDan]

Get the hammer out and bash that lip out of the way.

[GRPABT1]

Blakey wrote:

GRPABT1 wrote:

Blakey wrote:

and @ GRPABT1 wouldn't going to -40 make it stick out another 17mm, the way i see it the Tyre is center to the rim no matter what rim you use, so changing from 8" to 7" shouldn't make the Tyre move at the same offset, or am i getting this offset thing all wrong. so even getting a 7" rim at -23 offset the Tyre will be in the same place as the 8" rim at -23 offset,

Yes you have this offset thing all wrong. the number -23 is a measurement in mm that the mounting surface is from the centre line of the rim. So an 8" rim has a centreline 4" from each edge of the rim and a 7" rim has 3.5" from the centreline to the edge. So the same offset on different width rims has different distances from the mounting surface to the edge of the rim.

So for example an 8" rim with -24 (round that 24mm off to an inch) has 3 inches from the wheel mounting surface towards the inner guard and 5 inches sticking out. A 7" rim with -24 will have 2.5" towards the inner guard and only 4.5" sticking out. So whilst you gain some more inner guard clearance with the same offset on a smaller rim you will still lose some overall track width. My suggestion of 15X7" rims in -40mm works out to give you about the same overall track width and an extra inch or so inner guard clearance as a 15X8 -24. capish?

its not the rim that hitting anything its the tyre, the tyre is always central to the rim, so if i have a 7" rim or a 8" rim the tyre will always be central to it. so if i had the same offset on each the tyre would be in the exact same spot as the tyre doesn't get smaller with a smaller rim.

also its outer clearance that i have issues, as its the outside of the tyre that hits that lip. when at full lock

The same offset on a different sized rim changes the positioning of the centreline of the rim! The tyre does run central to the rim but if you alter the offset the tyre moves with the rim. The same offset on different sized rims will have the tyre in different positions.

I give up

[atari4x4]

Blakey wrote:

I made a mock up tyre out of wood lol dunno how accurate it is, but made a 31" plank of MDF then put a 10.5" Piece on top at the appropriate offset from center. but i cant flex it up like that

not many tyres actually measure true size, they are usually under sized more often than oversized.

[SierraDan]

Grinder and a hammer. That will solve the issue of your tyre just barely touching that excess.
Your tyre isnt likely to be bang on 31x10.5 anyway.

[BlueSuzy]

The Insa's are going to be undersize. Ive seen a sierra bloke that had a 35's, they looked quite small..

If you think your close, Buy them, Put them on, if your worried, (obviously your not worried with looks)get the BFH out.

Get rid of that tiedown point, cut it off and make up some proper recovery points. That thing is huge!! the older jims have smaller ones.


ps. love the cartwheel

[Blakey]

hmm well as it seems i cant find anywhere in brisbane that sells insa's so it looks like ill be changing to something else maybe something like silver stone MT117 Xtreams. unless someone know another good reasonably priced Tyre

[atari4x4]

whoops i missed the insa tyres bit...

i have the insa turbo special track's in a 235/75r15 & they're are taller than my 31" MTR's probably a better size for a jimny anyway being a bit narrower than a 10.5"
235/75r15's v 31/10.5r15

[BlueSuzy]

viewtopic.php?f=1&t=31704

not much tech but few brands

[Blakey]

just did a bit of reserch on thoes silvertone MT117X are actually a bit smaller then what they say at 9.6 Tred Width and 30.something dia. so im gonna go with them as at that smaller size they wll fit easy. ill still hammer thoes lips down tho. just for more clearance.

[zooky08]

You'll only need a 15x7 -13 rim for 30's then

[ZookFan]

SierraDan wrote:

Blakey wrote:

SierraDan wrote:

with a -23 offset im assuming you're looking at an 8" rim.
10.5" tyres suck on 8" rims.

how so what does that cause? and yes i was going to go 8" rim

When you air down to a useable pressure the tyre isn't on the bead as strong as it could be on a 7" rim.
So losing a bead is more likely. And mud/dirt in the bead is inevitable.

Good point mate...

[smiffkid]

I've ran 31s on 3 different offsets with only 50 mm lift
The first was a 15x7-12 and they didn touch and where full lock of flexed. Tho Ive hammered the floor and cut guards.
Second was a 15x8-25 they rubbed on the floor when flexing but no where else
Currently running 15x8-13 and they only rub when turnin on full flex still with 50mm lift.
So IMO u don't need that offset for 31s Expecially if u wanna keep it legal

[Bugsta]

Blakey wrote:

What are these flares please?