Club 80-90 Forums

Please don't shoot me - I haven't got a syncro.

But I do want some good off road tyres for my 2 wheel drive T25. I've looked and can't find tyres with a rolling circumfrance to match the original spec. My Rims a ex vauxhall 16" and at present have 255/50r16 fitted. Although this is close to the original rolling size, I have a +10% speedo reading. All the off road tyres i could find are arounf 750 circumfrance which would increase speedo error (& gearing) more.

This leads me to a couple of questions.
Are there any off road tyres that will fit?
Can I mix sizes front to back?
Is there a way to recalibrate speedo (roughly will do)?

Thanks

Off road tyres are usually of a much higher profile than road tyres, so will increase your rolling radius unless you fit smaller wheels. The best wheel size for off road tyres on a Type 25 is 15"

As far as I'm aware, 16" wheels will only fit a standard Type 25 with low-profile tyres (ie not off-road tyres) and there isn't the choice of off road patterns in 14" sizes.

Thanks but even at 15" I can't find the right size.

Will going big on the back cause any problems?
I only need 'push' as I get stuck in fields when camping. I'm not doing proper off roading so steering isn't too much of an issue for me (unless you parked your tent infront of me )

Go to this website (below). About three quarters of the way down is "a tyre size calculator", which allows you to calculate exactly how close or far from original your new tyes/wheels will be. The only drawback is that you need to input the original size to start with (ie. the stock 14 inch wheels and tyres) in order to get a start point, with correct speedo readings etc.
But once you've got that, you can try a few different sizes (new) until you get as close to stock as you can.

http://www.carbibles.com/tyre_bible_pg4.html" onclick="window.open(this.href);return false;

Or try 4x4 tyres .co.uk. I have just taken delivery of a set of 15" Mefro's from Brickwerks and plan to fit

215/75 15 BFG m/t's for offroad use.

You can of course fit larger tyres to the rear of your 2wd ( I did on my previous 2wd van )

You may also consider raising the ride height to give more scope.

Then you could fit an LSD or difflock for maximum traction!!!!!!!

Don't limit yourself to off road tyres, look at winter tyres too. They will get you off most muddy campsites

^WHS

I've got winter tyres on standard 14" rims on my camper and they get me out of most mush.

Personally I would be looking for a 15inch wheel and a bfg a/t in 215 75 15 or the general grabber equivalent, if you still want to keep the 16inch wheel i think the the bfg a/t is made in a 225 70 16 which is not too far away from a 215 75 15, however remember that larger wheels and tyres have an effect on the breaks, drive train and suspension which need to be considered,

Neil

Personally I would be looking for a 15inch wheel and a bfg a/t in 215 75 15 or the general grabber equivalent, if you still want to keep the 16inch wheel i think the the bfg a/t is made in a 225 70 16 which is not too far away from a 215 75 15, however remember that larger wheels and tyres have an effect on the breaks, drive train and suspension which need to be considered,

Neil

pfield69 wrote:Please don't shoot me - I haven't got a syncro.

But I do want some good off road tyres for my 2 wheel drive T25. I've looked and can't find tyres with a rolling circumfrance to match the original spec. My Rims a ex vauxhall 16" and at present have 255/50r16 fitted. Although this is close to the original rolling size, I have a +10% speedo reading. All the off road tyres i could find are arounf 750 circumfrance which would increase speedo error (& gearing) more.

This leads me to a couple of questions.
Are there any off road tyres that will fit?
Can I mix sizes front to back?
Is there a way to recalibrate speedo (roughly will do)?

Thanks

Hi there.

If you have 255/50/16's on your 2wd van at the moment and if they are close to the original rolling radius then please dont rush out and buy 215/75/15's or the 225/70/16's. This will give you a 11.57% taller gearing and 73mm extra rolling radius on the 215/75/15's and you will run the risk of ripping your front wheel arches off (ask me how I know ) If you go M/T its guaranteed

I might be wrong but hope this helps,

Jed

Second on a set of winters.
They will wear fast if you use them in really hot weather, not that we get a lot of that

Think that covers all bases from the sublime to the rediculous !! (me)!!

It's up to you and what you need your van to do.

Higher profile m/s tyres on rear would undoubtedly help.

pfield69 wrote:Thanks but even at 15" I can't find the right size.

205/65/15 .... and they do a reinforced tyre and a winter tyre

Its the same size as a 185r14

I've posted here too https://club8090.co.uk/forum/viewtopic.php?f=41&t=114823" onclick="window.open(this.href);return false; byt had no replies.

I was thinking 215/70r16.

These appear easy to get in off road and although they have a 12% larger circumferance, they should make up for my constant 10% faster speedo reading (i.e. current wheel spinning too fast/ too small).

Any thoughts on this size of 4x4 tyre?

Doesn't the speedo drive off the nsf wheel? If so you could fit tyres with the same original circumference to the front and fit larger to the rear but then you may have to carry 2 spares!!!!

Can't suggest tyre choice as I'm running 215/75/ 15 mt's