What size tyres can I upgrade to with my BT-50

JamieMaynard

New Member
I have a 2010 bt 50.. What is the max size tyres people are getting underneath it? I've already got a 2" suspension and am probably going to body lift another 2 soon...
 

vk1dx

Well-Known Member
What does the tre plate on your door frame say. I think that it is one or two sizes about that. Or go and see an engineer and do all the stuff for a vehicle modification and then take it over the pits.

The standard on our plate is a 265. We have 285's and all okay with the RTA.

Phil
 

Albynsw

Well-Known Member
What does the tre plate on your door frame say. I think that it is one or two sizes about that. Or go and see an engineer and do all the stuff for a vehicle modification and then take it over the pits.

The standard on our plate is a 265. We have 285's and all okay with the RTA.

Phil
With a 2 inch suspension lift and a 2 inch body lift I don't think he is too concerned about the legalities side of things.

Jamie I don't know the answer to your question but keep in mind gearing and brakes as you might find yourself have to change/ upgrade those as well if you go too big.
 
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Albynsw

Well-Known Member
That's one hell of an assumption Alby. You haven't any right to judge him.

You never know he may want to know.

Phil

Reply yeah fair call Phil, my assumption is what usually happens but I shouldn't have just assumed that was the case
 

Les PK Ranger

4x4 Earth Contributer
Some folk might not be aware of the a) running issues or b) the legalities of combined suspension lift, body lift, increased wheel / tyre size.
That's where this and other forums are so great, let's people know just what they need to research more.
 

phs

Well-Known Member
I'm happy to judge. 2" suspension / 2" body.
Don't think he is to concerned.

But if people would like to read page one there is info there regarding BT50s and tyre size specifics


2010 bt-50 ( 245/70r16 ) 749.3mm OD tyre
As far as how big you can go legally that will depend on what state you are in ...

The common 285/75r16 will be too big for any state unless you get it engineered
 

Les PK Ranger

4x4 Earth Contributer
Hmm, that is good, the link I posted has the comparison page tab, but I like the visualiser on your link page too.
 
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Spooner

Well-Known Member
I need new tyres for mine , haven't decided what type A/T or M/T but I will stick to standard size .
Either way will be an improvement . The thing get's around a lot of stuff on Hwy tyres, that I would not have thought possible , until I tried it.
 

Darb W

New Member
Just bear in mind that while in every other state you can increase the tyre rolling diameter by 25mm without certification, in Victoria if your vehicle has mandated Electronic Stability Control, to can't increase the tyre rolling diameter at all, without an engineer's certificate. You're stuck with what's on the tyre placard, full stop. Not usually a problem until it's a disaster and you're not insured.
 

CptnBarney

New Member
I thought there were changes to ESC equipped vehicles late in 2015 regarding suspension and tyres. Best advice is to ring your insurer, run the tyre size by them, let them make the call.
 

BT50-Max

New Member
Hi Everyone, I have come across a tyre that would make the 285/70/17 legal in most states.

The standard tyre size on any 2011+ BT50 4wd is 265/65/17 and most tyres in this size are 776mm meaning max based on the 50mm allowable increase is 826mm. This limits to 275/70/17 which is available but only a small number of tyres. I did a little digging and came across the General Grabber AT3. The specs on this tyre in the 265/65/17 size state a diameter of 790mm, not 776. I had to check this twice but it is legit. As the regs only state that a tyre can be only increase by 50mm from the largest available tyre listed on the tyre placard (in this case 840mm based on the Grabber AT3) we can now look at 285/70/17 tyres as most in this size are 831 - 836mm so well below the 840mm. I wasn't sure if this is common knowledge but for those after the 285 tyre and wanting to remain legal this is proof we can.
 

Lost1?

Well-Known Member
I wouldn't recommend you try to manipulate differing tyre diameters to justify how you made a decision. Plod won't be particularly interested in what you have to say if you get pinged in at a vehicle inspection station one weekend. You will end up with a yellow sticker on your vehicle and be left feeling somewhat aggrieved. Stick with the 275/70 or check out the 255/75 federal AT tyre if that suits.
 

BT50-Max

New Member
Very true. I believe the only issue would be DOT. I have a friend with a Ranger that has 35" tyres and the Plod aren't even interested.
 

BT50-Max

New Member
Hi All,

I just wanted to clarify that based on the research that I have been doing, I believe the 285/70/17 size tyre is the largest tyre that is legally able to be fitted to a standard XLT / BT50 that comes with 265/65/17 standard. For our friends that are lucky enough to live in NSW, they have no issues as they have an allowance of a tyre increase of +7% in diameter which I believe the 285 is a 6.9% increase. But for us souls who live in Qld, Vic and WA (probably all other states) we are limited to the NCOP increase of 50mm.

Having read the NCOP regulations closely I note the following statement: " Must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the
vehicle manufacturer for that vehicle. "

This statement means ANY tyre in the size 265/65/17 as this is the tyre designated by the manufacture, not brand, just the size is mentioned.

I next trawled through what seemed like hundreds of tyre specs in 265/65/17 and noted most range in size from 775mm to 778mm but there are a few that were beyond this size. The 2 that I have focussed on are the General Grabber AT3 and Blackbear RT tyre, both in 265/65/17. According to the specs clearly noted on their website, the Grabber AT3 in 265/65/17 size has an OD of 790mm and the Blackbear R/T tyre has an OD of 783mm.

So based on the NCOP guidelines, by adding the 50mm allowable increase this allows for an increase to a tyre OD of between 833mm and 840mm. Most 285/70/17 tyres fall within this range so based on this I have no doubt that the 285 tyre size is legal.

Based with this information I purchased 285/70/17 tyres (Yokohama X-AT) on stock BT50 XTR rims and they do not look out of place at all and are well within the wheel arches. No issues with scrubbing as yet also.

Just thought that I would put the info out there so there is complete transparency on the case as well.
 

Lost1?

Well-Known Member
275/70R 17 is the largest legal tyre size you can fit. If 16 inch rims will fit your vehicle I would recommend 265/75R16 tyres over anything available in a 17 inch rim size. I know you tried to using differing tyre diameters quoted by tyre manufacturers in an earlier post to validate how you made a decison. That is not how the various state road transport entities or Plod view things. You could engineer 285/70R17 or 285/75R16. How badly do you want 33" tyres?
 
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