Tyre Sizes
- Bulletproof
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Tyre Sizes
A recent post said there are two different sizes of Simex extreme treeker 35x11.5x15 tyres
For future reference I am interested in the correct height of a tyre because then I know what to buy for diff clearance
I read of alot of different heights quoted for the same tyre.
There is only one correct way to measure a tyre and that is to run a piece of non stretch string around the Circumference and then measure this with a tape.
Dont run a tape around because it doesn't sit flat and will give a measurement about 30mm too long.
My Simex ET 35x11.5x15 measure 2840mm / by 3.1415 =903.16mm .Then / by 25.4 =35.55 inches
My BFGs MTs 35x12.5x15 measure 2785mm / by 3.1415 =886.51mm. Then / by 25.4 = 34.90 inches
Interested to know how other brands and sizes measure.
Cheers Richard
For future reference I am interested in the correct height of a tyre because then I know what to buy for diff clearance
I read of alot of different heights quoted for the same tyre.
There is only one correct way to measure a tyre and that is to run a piece of non stretch string around the Circumference and then measure this with a tape.
Dont run a tape around because it doesn't sit flat and will give a measurement about 30mm too long.
My Simex ET 35x11.5x15 measure 2840mm / by 3.1415 =903.16mm .Then / by 25.4 =35.55 inches
My BFGs MTs 35x12.5x15 measure 2785mm / by 3.1415 =886.51mm. Then / by 25.4 = 34.90 inches
Interested to know how other brands and sizes measure.
Cheers Richard
Never say die, up man and try
Re: Tyre Sizes
bare in mind my tyres are over 4 years old and have done a couple of skids
36x12.5x15 centipede
910.02mm = 35.82"

36x12.5x15 centipede
910.02mm = 35.82"
If you already know everything, DON'T ask bloody questions!!
Re: Tyre Sizes
Bulletproof wrote:There is only one correct way to measure a tyre and that is to run a piece of non stretch string around the Circumference and then measure this with a tape.
Cheers Richard
At a certain pressure? 4x4 Challenges is at 30 psi for measuring if i remember correctly
- Bulletproof
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Re: Tyre Sizes
My 35x11x15 ET was at 34lbs and I have just let it down to 30 and it measures exactly the same.
35.55inches
Haven't checked the BFG pressure yet
Im still hoping that Simex bring a 36 out in a 2 lug
Cheers Richard
35.55inches
Haven't checked the BFG pressure yet
Im still hoping that Simex bring a 36 out in a 2 lug
Cheers Richard
Never say die, up man and try
Re: Tyre Sizes
Bulletproof wrote:My 35x11x15 ET was at 34lbs and I have just let it down to 30 and it measures exactly the same.
35.55inches
Haven't checked the BFG pressure yet
Im still hoping that Simex bring a 36 out in a 2 lug
Cheers Richard
what you can do (if your not doing comps) is remove every second centre block leading in from the paddles... then you would have the best of both worlds

to show you what i mean you would remove the red ones

thebn you would have the width and the open blocking where it counts

If you already know everything, DON'T ask bloody questions!!
- MNC
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Re: Tyre Sizes
wopass wrote:what you can do (if your not doing comps) is remove every second centre block leading in from the paddles...
then you would have the width and the open blocking where it counts
Liking that idea


- Bulletproof
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Re: Tyre Sizes
Is no one interested what size tyres really are ?
About 10 years ago I ordered a set of super-swamper tyres and when they arrived were about 40mm smaller than what was written on the case so I sent them straight back.
To have a capable truck diff clearance is of upmost importance. More important than tread because if the wheels are not touching the ground you are going nowhere.
I thought a data base of what tyres really measure would help us all make the right decisions when buying tyres.
Cheers Richard
About 10 years ago I ordered a set of super-swamper tyres and when they arrived were about 40mm smaller than what was written on the case so I sent them straight back.
To have a capable truck diff clearance is of upmost importance. More important than tread because if the wheels are not touching the ground you are going nowhere.
I thought a data base of what tyres really measure would help us all make the right decisions when buying tyres.
Cheers Richard
Never say die, up man and try
Re: Tyre Sizes
Bulletproof wrote:Is no one interested what size tyres really are ?
About 10 years ago I ordered a set of super-swamper tyres and when they arrived were about 40mm smaller than what was written on the case so I sent them straight back.
To have a capable truck diff clearance is of upmost importance. More important than tread because if the wheels are not touching the ground you are going nowhere.
I thought a data base of what tyres really measure would help us all make the right decisions when buying tyres.
Cheers Richard
keen to hear about your bfg's
i have them on my truck ATM as well while i save for some mt112's
Kiwi4x4
Re: Tyre Sizes
35 x 11.5 x 16 Silverstone xtreme MT117X @ 35psi on 8 inch rim: 880mm=34.65"
has anyone noticed how tyres 'grow' from when they are new?
when I first put them on rims they had no bulge in the sidewalls and looked smaller than I was hoping. Then I spent a few hours offroad with them at 24psi and they have visibly bulged out a bit. this was proven when I put my road tires back on again and stuck one on the spare holder on the back door. when new could just open the door without tyre touching, now it touches by at least 5mm.
has anyone noticed how tyres 'grow' from when they are new?
when I first put them on rims they had no bulge in the sidewalls and looked smaller than I was hoping. Then I spent a few hours offroad with them at 24psi and they have visibly bulged out a bit. this was proven when I put my road tires back on again and stuck one on the spare holder on the back door. when new could just open the door without tyre touching, now it touches by at least 5mm.
- Bulletproof
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Re: Tyre Sizes
Measured 2 more sets I have today
33x12.5 x15 BFG MT half worn 830.81mm = 32.7 inches
750x16 near new SATS 799mm = 31.45 inches
Cheers Richard
33x12.5 x15 BFG MT half worn 830.81mm = 32.7 inches
750x16 near new SATS 799mm = 31.45 inches
Cheers Richard
Never say die, up man and try
Re: Tyre Sizes
measured mine
39.5 x 12.5 x 15 Interco Iroks at 6lbs = 992.9mm dia which is 39.09"
39.5 x 12.5 x 15 Interco Iroks at 6lbs = 992.9mm dia which is 39.09"
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- Andrew1706
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Re: Tyre Sizes
38x15.5x15 Parnelli Jones Dirt Grips
Used a measuring tape and got 3100 so 3070mm = 38.5"
25psi free standing in the air.
Used a measuring tape and got 3100 so 3070mm = 38.5"
25psi free standing in the air.
- Bulletproof
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Re: Tyre Sizes
Andrew1706 wrote:38x15.5x15 Parnelli Jones Dirt Grips
Used a measuring tape and got 3100 so 3070mm = 38.5"
25psi free standing in the air.
Good to see we are getting a data base.
I have never seen a Parnelli dirt grip. Looking on the internet they dont look that open and aggressive but how do they perform in real life and what terrain do they best suit ?
Cheer Richard
Never say die, up man and try
- Andrew1706
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Re: Tyre Sizes
Bulletproof wrote:Good to see we are getting a data base.
I have never seen a Parnelli dirt grip. Looking on the internet they dont look that open and aggressive but how do they perform in real life and what terrain do they best suit ?
Cheer Richard
You are right Richard, they don't seem to be very open especially the centre lugs (the P J bits) but the side luges are quite open with I would say 40mm between them.
I haven't used them yet as I'm still working on the truck but the guy I bought them off had them on his Safari and found in the clay they just wanted to keep climbing. He didn't have them on for long so I really don't know how they perform.
They are 15.5" wide so theres a lot of rubber on the terrain and the previous owner said they were good in the sand because of this.
- Bulletproof
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Re: Tyre Sizes
I looked at the Simex site today and it said there was an ET 35x12.5 x15 2 lug with a dia of 911mm.
When I bought mine these were a 3 lug.
Is this true and if so does anyone have them ?
Are they true to size ?
Cheers Richard
When I bought mine these were a 3 lug.
Is this true and if so does anyone have them ?
Are they true to size ?
Cheers Richard
Never say die, up man and try
Re: Tyre Sizes
Bulletproof wrote:I looked at the Simex site today and it said there was an ET 35x12.5 x15 2 lug with a dia of 911mm.
When I bought mine these were a 3 lug.
Is this true and if so does anyone have them ?
Are they true to size ?
Cheers Richard
That would make them bigger 36's. It must be a mistake.
Last edited by tgaguy1 on Sat May 09, 2009 7:54 pm, edited 1 time in total.
Re: Tyre Sizes
Bulletproof wrote:I looked at the Simex site today and it said there was an ET 35x12.5 x15 2 lug with a dia of 911mm.
When I bought mine these were a 3 lug.
Is this true and if so does anyone have them ?
Are they true to size ?
Cheers Richard
Nah it must be a mistake the 35x12.5 are triple lugs ,Gene batty was running them on his V8 lux winch truck at NWWC this year ,he was driving quite a few hazards that others wernt but wether that was the tyres or his heavy right foot im not sure of ..
Re: Tyre Sizes
Maxxis creepy 35" (approx 20% worn)
2740mm(872mm) 34.3"
Maxxis creepy 37" (new 3 trips)
2940mm(935mm) 36.8"
2740mm(872mm) 34.3"
Maxxis creepy 37" (new 3 trips)
2940mm(935mm) 36.8"
- hosehustler
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Re: Tyre Sizes
MNC wrote:The 35x12.5x15 King Cobras = 2.68m circumference which equates to 33.59" Diameter.
are you running these?
keen to hear what they perform like

I hate signatures
Re: Tyre Sizes
hosehustler wrote:MNC wrote:The 35x12.5x15 King Cobras = 2.68m circumference which equates to 33.59" Diameter.
are you running these?
keen to hear what they perform like
x2
- MNC
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Re: Tyre Sizes
hosehustler wrote:MNC wrote:The 35x12.5x15 King Cobras = 2.68m circumference which equates to 33.59" Diameter.
are you running these?
keen to hear what they perform like
If my truck doesn't meet reserve today then one of the options I was thinking of was to keep it and get some more aggressive offroad tires.
My truck is certed for 33's which these tires actually are and I dont have much room (without chopping the body) to fit bigger tires so was thinking these could be a good option.
Haven't heard alot about them but the tread pattern is nice and aggressive - would like to know how well they wear and bag at low pressures.
