Tyres

Joecarr

Member
Hi I have a mf 390 on 10.00-16 on front and 13.6 r38 on the back , I'm wondering can I change the back to 18.4 r34 ? Would they be the same height as 16.9 r34 or what's the doffrence ? Would it have a greater rolling confrance?
 
Hi I have a mf 390 on 10.00-16 on front and 13.6 r38 on the back , I'm wondering can I change the back to 18.4 r34 ? Would they be the same height as 16.9 r34 or what's the doffrence ? Would it have a greater rolling confrance?

The 16.9 r34 will be very close to the 13.6 r38 in terms of the rolling circumference and height. The 18.4 will be a bit bigger, I'm wondering here will you get it under the mudguards? It will have a greater rolling circumference.

We come along by the way.
 
Yes, the 18.4 x 34 will fit under the mudguards, when 590s were the main tractors here we ran them 18.4 x 34s . on them with 8 speed boxes it added just shy of 1 mph to the top speed , 17 mph :rolleyes2:
 
Hi I have a mf 390 on 10.00-16 on front and 13.6 r38 on the back , I'm wondering can I change the back to 18.4 r34 ? Would they be the same height as 16.9 r34 or what's the doffrence ? Would it have a greater rolling confrance?
An 18.4 r34 is roughly the same height as a 16.9r 38 so would be a bit taller than a 16.9r34
 
The 16.9 r34 will be very close to the 13.6 r38 in terms of the rolling circumference and height. The 18.4 will be a bit bigger, I'm wondering here will you get it under the mudguards? It will have a greater rolling circumference.

We come along by the way.

Would this mean then that the 18.4 would make the tractor a bit faster ?
 
Yes, the 18.4 x 34 will fit under the mudguards, when 590s were the main tractors here we ran them 18.4 x 34s . on them with 8 speed boxes it added just shy of 1 mph to the top speed , 17 mph :rolleyes2:
Would she be sitting level then no ? I only have 10.00-16 on the front
 
Hi I have a mf 390 on 10.00-16 on front and 13.6 r38 on the back , I'm wondering can I change the back to 18.4 r34 ? Would they be the same height as 16.9 r34 or what's the doffrence ? Would it have a greater rolling confrance?
Welcome along, Joe.
Do you mind if I ask what you are looking to achieve? Are you looking to go 2nd hand or new?
18.4 R34's are a big change from where you are, you will gain speed, (approx. 5%) and loose tourque, (approx. 6%).
They are not that common and so are harder to come by 2nd hand, they also need wider rims than are usually available, (they should be on 16" wide rims but will fit 15") a lot of the rims 2nd hand are 13" or 14".
 
Welcome along, Joe.
Do you mind if I ask what you are looking to achieve? Are you looking to go 2nd hand or new?
18.4 R34's are a big change from where you are, you will gain speed, (approx. 5%) and loose tourque, (approx. 6%).
They are not that common and so are harder to come by 2nd hand, they also need wider rims than are usually available, (they should be on 16" wide rims but will fit 15") a lot of the rims 2nd hand are 13" or 14".
Thanks , i can get a set of second hand rims and tyres of either of my choice, we have the 13.6 r 38 for spraying corn ect, but in summer we draw silage, straw etc with her and the narrow wheels arnt suiting , when I was offered the both wheels I'm just wondering what do yee think would suit best for the tractor . It's a massey 390 hiline
 
Thanks , i can get a set of second hand rims and tyres of either of my choice, we have the 13.6 r 38 for spraying corn ect, but in summer we draw silage, straw etc with her and the narrow wheels arnt suiting , when I was offered the both wheels I'm just wondering what do yee think would suit best for the tractor . It's a massey 390 hiline
The 16.9 R34's will be way more common and easier to find 2nd hand if you ever need a replacement.
The 18.4 R34's will give you a small bit more speed and do less damage on wet ground, allowing you travel better in marginal conditions, but the tractor will seem a bit back in power and die back sooner on hills with a load.
I would decide based on the brand and quality of the tyres of each size you are being offered, a good quality brand and less worn 16.9 will be much more use to you than a poorer 18.4, and vice versa.
More modern radial tyres will be stamped 420/85 R34's replaces 16.9 R34's and 460/85 R34's replaces 18.4 R34's
 
You could also go 11.00-16 on the front if you wanted to keep it level, but it wouldn't be that noticeable.
Ok thanks
The 16.9 R34's will be way more common and easier to find 2nd hand if you ever need a replacement.
The 18.4 R34's will give you a small bit more speed and do less damage on wet ground, allowing you travel better in marginal conditions, but the tractor will seem a bit back in power and die back sooner on hills with a load.
I would decide based on the brand and quality of the tyres of each size you are being offered, a good quality brand and less worn 16.9 will be much more use to you than a poorer 18.4, and vice versa.
More modern radial tyres will be stamped 420/85 R34's replaces 16.9 R34's and 460/85 R34's replaces 18.4 R34's
thanks cery much for your reply , could I ask why would she lose power with the bigger wheels as a matter of interest ? Or whats the reson for it
 
Ok thanks

thanks cery much for your reply , could I ask why would she lose power with the bigger wheels as a matter of interest ? Or whats the reson for it
You won't lose power per se, but the bigger diameter tyres take more power to drive in any given gear so your tractor will seem to have lost a bit of power.
It will only be perception in general, drop a gear and on you go.
 
Welcome , Joe.
I have a Zetor 8145 , which is fitted with 460/85 x 34 rears, the metric version of 18-4 x 34s.
I had terrible trouble getting a pair of them, and that was new. Rare as rocking horse poo.
You will be told “That size is only on a Zetor , or a very odd Landini”. You haven’t a hailstones chance in hell of finding a s/h pair.
You will have to give €700 odd? For a new radial of that size , plus I assume you will have to buy a pair of rims and tubes.
You have a good chance of getting a S/H pair of 16.9 x34 , or a good choice of newtyres in that size.
 
Welcome , Joe.
I have a Zetor 8145 , which is fitted with 460/85 x 34 rears, the metric version of 18-4 x 34s.
I had terrible trouble getting a pair of them, and that was new. Rare as rocking horse poo.
You will be told “That size is only on a Zetor , or a very odd Landini”. You haven’t a hailstones chance in hell of finding a s/h pair.
You will have to give €700 odd? For a new radial of that size , plus I assume you will have to buy a pair of rims and tubes.
You have a good chance of getting a S/H pair of 16.9 x34 , or a good choice of newtyres in that size.

I was looking at a landini 9880 with them fitted the other day and I think @nashmach has them fitted on his one. I'd go for a set of 16.9/34s as there a far easier tyre to pick up and buy.
 
I was looking at a landini 9880 with them fitted the other day and I think @nashmach has them fitted on his one. I'd go for a set of 16.9/34s as there a far easier tyre to pick up and buy.

I totally agree with you Peter.
BUT , because of the 4 wd and care needed not to mess with ratios , I had to stick with the 18-4. I had put new front tyres on it 6 months prevviously . OP far better to stick to 16.9 a.
.
 
I was looking at a landini 9880 with them fitted the other day and I think @nashmach has them fitted on his one. I'd go for a set of 16.9/34s as there a far easier tyre to pick up and buy.

Thats correct Peter, they are on most 9880's.

I'd agree with all that the lads say above on the 16.9s as much as I prefer wider tyres now.
 
Hi I have a mf 390 on 10.00-16 on front and 13.6 r38 on the back , I'm wondering can I change the back to 18.4 r34 ? Would they be the same height as 16.9 r34 or what's the doffrence ? Would it have a greater rolling confrance?
480/70/34 will be a good option for you as you stY the same height but gain more width.
 
@gone . Question for you re tyres . Rake here has the tyre in the second pic . First pic is of the tyre on the Baler . Will they fit each other's rim
? . Price difference between the 2 tyres is €70
 

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Lads anyone know where I would be able to get 13.6 r38 wheels and tyres for a mf . need to be 50% or better
Try Noel O Connor in Wexford, he advertises lots of row crop wheels on DD regularly. I’d be surprised if he didn’t have a set.
You’ll have to check DD for his number, I don’t have it to hand.
 
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