29+ tyres and 'normal' rims

Viewing 6 posts - 1 through 6 (of 6 total)
  • 29+ tyres and 'normal' rims
  • I know there’s lots about this all over the internet – but struggling to find out just the very basics.
    I know 29+ tyres like the knard are designed for rims 35mm+ and running them on narrow rims can mean they fold over or need higher pressure…but what do you class as a ‘narrow’ rim, and is that internal or external rim width?
    Eventually i’ll change rim, but in the short term looking for a larger tyre for more comfort on a rigid bike, which is pointless if i have to still run it at higher pressures.
    cheers

    cokie
    Member

    I’ve seen someone run a Knard on a Stans Crest rim 😯 !
    It works in the sense that it doesn’t burp and rolls, but it loses all of it’s benefits- by pinching the tyre you don’t get the large footprint and it make the tyre an odd shape.

    Premier Icon mos
    Subscriber

    The extra pressure needed to stop it from rolling off the rim kind of negates some of the benefits such as comfort. Plus they can get extra bouncy in the rough.

    Thanks mos/cokie – yep, that’s what i expected.
    So without a 35mm+ rim there’s just no point bothering with a + tyre.

    Premier Icon thisisnotaspoon
    Subscriber

    I think the rule of thumb is a minimum 2:1 on tyre size to rim width with fat bikes (4″ tyre on a 50mm rim etc). So a 3″ tyre is going to struggle on anything narrower than 35-40mm.

    Premier Icon ajantom
    Subscriber

    I have been running a Knard on the back of my Krampus on a Pacenti DL31 (31mm outer, about 27mm inner) for a year.
    Maybe have to put a couple of PSI more in it – I run the front on a 50mm rim at 13/14 PSI, so the rear is at 15/16 ish. Had zero problems with roll, and comfort is fine.

Viewing 6 posts - 1 through 6 (of 6 total)

The topic ‘29+ tyres and 'normal' rims’ is closed to new replies.