New tyre recommendation please.

[Blade]

I've recently worn out the rear tyre on my recumbent trike.

In the past, when considering tyres my primary concerns have always been rolling resistance and puncture resistance. Durano's have served me well although the ride has always been a bit harsh due to my trike lacking suspension. However, having recently motorised my trike, I thought about fitting a tyre which although having more rolling resistance might give a more comfortable ride.

The rear wheel has an Alex DA22 rim which has the following dimensions: Diameter 451 mm.   External width 22 mm. Internal width 14 mm. Current tyre fitted is a 28 mm. Not sure how wide a tyre the rim would take.

Any recommendations would be greatly appreciated.

The trike is used exclusively on tarmac roads, so an aggressively  treaded tyre is not needed.

[LittleWheelsandBig]

https://alexrims.com/faq/ might help you pick a maximum tyre width.

There isn’t a huge range of tyre widths in 451.

[fd3]

The CTC recommendation is width x2.2 iirc, but the issue with oversized tyres on rims is due to cornering (aiui) so conventional wisdom prob flies out the window.

[LittleWheelsandBig]

Wide tyres on narrow rims need higher pressures than on wide rims to avoid rolling sideways in fast corners. Trikes need slightly higher pressures than bikes for the same reason. Sidewall stiffness affects these recommendations.

Overly-wide tyres on narrow rims tend to damage sidewalls at lower pressures and higher weights. Higher pressures on wide tyres boost the tension in the casing threads.

If you are running higher pressures to keep the tyre stable, you lose some of the benefits of wider tyres.

[Tigerbiten]

I use a 50-406 big apple on the back of my trike mainly because  the rubber compound making up the tread is thicker than the faster 40-406 tyres I use on the front.
This gives me twice the thickness of rubber to wear off before I need to change the tyre, so front and back tyres tend to wear out at the same time.
So I think it's not so much how wide the tyre is, it's more about how much rubber there is to wear off before getting down to the carcass threads.
The trouble is I don't know a good 451 tyre that has a thick rubber tread.

Luck ...... 

[Lightning Phil]

The CTC recommendation is width x2.2 iirc, but the issue with oversized tyres on rims is due to cornering (aiui) so conventional wisdom prob flies out the window.

They recommend a ratio of tyre width / internal rim width of 1.8, here is what they say

“The ideal relationship between tyre and rim section is about 1.8 to 1, but any tyre from 1.4 to 2.2 times should fit – always provided that the bead diameters correspond.”

[fd3]

Yeah, I was thinking max as the question was max size.
Schwalbe reckon that once you go to wider rims you can go significantly larger than this.

[LittleWheelsandBig]

Does anybody make a tyre wider than 37 for 451 rims? Not that I know of.

To fit a significantly wider tyre, you would need to rebuild on a 406 rim.

[Blade]

Thanks for all your input.

I didn't realise how limited the availability of 451 tyres was.

I've ordered another 28mm Durano Plus tyre as I know that that works with my rims.

However, I've also ordered a cheap 37 mm tyre to see if they will fit safely on my rim. If it doesn't work out then not too much lost.