700C tires on a 29er- Possible or not?

[mcfee03]

Hi,

I've heard/read mixed comments on fitting 700C tires on a 29er.

My rims are Giant S-XC Sport 29er, double wall, alloy, 32H disc

I have some 700 38C and a 700 40C tires- will they fit on this rim? And can I use my existing tubes in my original tires (29 x 2.1”)?

Thanks

[darkhorse75]

700C = 29er. The only limiting factor is the width of the rim and tyre combination. Wider tyres will generally fit on narrow rims, but narrow tires on wider rims sometimes wont work. Scroll down to width considerations.http://sheldonbrown.com/tire-sizing.html" onclick="window.open(this.href);return false;

[trailgumby]

YEs you can fit those tyres, but the tubes will likely be too fat.

Why you u no run tubeless on mountain bike?

[mcfee03]

YEs you can fit those tyres, but the tubes will likely be too fat.

Why you u no run tubeless on mountain bike?

This is something I definitely want to try. I'm prone to getting flats/replacing tubes. Are my tires "tubeless" ready? Is it a more reliable option?

700C = 29er. The only limiting factor is the width of the rim and tyre combination. Wider tyres will generally fit on narrow rims, but narrow tires on wider rims sometimes wont work. Scroll down to width considerations.http://sheldonbrown.com/tire-sizing.html" onclick="window.open(this.href);return false;

Thanks. How do I know the width of my tires?

And do I risk anything by testing out my 29x2.1 tubes on 700 38c & 700 40c tires?

[find_bruce]

You can squeeze a "too big" tube into a tyre but it will have lumps & bumps & won't roll smoothly.

Whereabouts are you? If you're in Sydney you are welcome to use a 38 tyre to test fit on your wheel & frame.

[mcfee03]

You can squeeze a "too big" tube into a tyre but it will have lumps & bumps & won't roll smoothly.

Whereabouts are you? If you're in Sydney you are welcome to use a 38 tyre to test fit on your wheel & frame.

Thanks for the offer- but I've already got the tires. Has anyone tried a setup on the tubes? If I went for any entirely tubeless setup- would the 700's and 29x2.1's both work?

[Calvin27]

Mostly depends on pressure. the 2.1 will very likely work well depending on tyre/rim combination and how the tubeless gods are feeling on the day. 700c will depend on the same things but also the pressure. Tubeless at high pressure has not really been mastered yet and the only examples I've seen are for dedicated road tubeless rim/tyres.

[Thoglette]

The only difference between 29er and normal 700c is intended tyre width - which is reflected in the rim width (and frame clearances). They are both ISO 622 rims.

You are going to need a tube ROUGHLY the same size as your tyre, but over/undersized tubes will work, for a while (undersized tubes tend to die early!)

Finally, 29er rims TEND to have Schrader (car) valves and 700C tend to have Presta (skinny) valves.

Why you u no run tubeless on mountain bike?

Because tubeless remains a solution in search of a problem.

[Duck!]

Finally, 29er rims TEND to have Schrader (car) valves and 700C tend to have Presta (skinny) valves.

Not really. Cheap wheels tend to be drilled for Schraeder valves, better wheels are drilled for Presta.

[mcfee03]

Well I'd like to try it out today- but turns out my pump is missing the piece for the Shrader valve. It's like a rubber valve stem- stops the back flow of air. I only just bought the pump... I started a thread about it. viewtopic.php?f=34&t=81866

[m@]

700C tyres on 29er rims works just fine; just beware of running narrow (25C and below) tyres on wide rims. I destroyed an almost new set of 23C Conti GP4000Ss (and very nearly myself) hitting something at relatively low speed - the tyre sidewalls suffered ~5mm long snakebite punctures.

Thanks for the offer- but I've already got the tires. Has anyone tried a setup on the tubes? If I went for any entirely tubeless setup- would the 700's and 29x2.1's both work?

Your wheels can be set up tubeless, but will need a conversion kit - best option is Bontrager, which you can buy from a shop that sells Trek bikes. Unless Giant have changed the rim width in recent years, the 'road' kit is the one to go for. You'll also need some sealant - Stan's is fine - and installation will be much easier with an air compressor. Your best option is to buy the sealant and strips (and tyres if necessary) at the shop when they're not too busy, and ask nicely if they'll install the tyres for you.

Road tubeless I wouldn't bother with; whether your MTB tyres can be run tubeless depends on the tyres! My Giant Anthem 29er came with tubeless ready Schwalbe Racing Ralphs, but some of the other models are supplied with cheaper tyres with thinner, porous sidewalls that aren't suitable for running tubeless. If they are Schwalbes, look for the "TLR" logo, or "snakeskin" printed on the sidewall. If either/both are there, they can be run tubeless. If you've been riding them for a while, the sidewalls will have lots of pinholes so it will take them a while to seal up. The best way to help this happen is to go for a ride, as it distributes the sealant around the tyres - but you can also sit them on a bucket overnight, flipping them every so often so both sides get a chance to seal. I haven't had a flat of any kind since switching to tubeless, and have gone through two sets of tyres (not that that takes long running Schwalbe Evos...).

But I wouldn't go tubeless if you're planning on switching tyres frequently - the cost of replacing the sealant each time will justify a second wheelset pretty quickly. There are plenty of second-hand Giant 29er wheelsets out there that are perfect for a day-to-day set, or you could buy something nicer for the MTB wheelset and use your existing set for road duty.

[Thoglette]

Not really. Cheap wheels tend to be drilled for Schraeder valves, better wheels are drilled for Presta.

I think I'll file that quote for reuse - love it

[mcfee03]

700C tyres on 29er rims works just fine; just beware of running narrow (25C and below) tyres on wide rims.
...

But I wouldn't go tubeless if you're planning on switching tyres frequently

You're right- tubeless isn't practical for my needs.

So I could potentially run 25c's and up on my rim? That's pretty thin. I played it safe and grabbed a 38c & 40c, also in the hope of using the same tube. I will pump up my 29x2.1 tubes with them on today and report back. Should I run on lower PSI (ie ~40?) or go close to the maximum?

[m@]

25C is probably a touch on the risky side, though I have run them on my Giant wheels in the past without any issues; roll nice and fast compared to the 28s off my commuter, but they're a very different tyre so hard to make any direct comparison.

Personally I wouldn't be super comfortable running tubes that much larger than the tyre; tubes are cheap and it means less mucking around when switching tyres (as each tube stays with the tyre). Though of course running narrower tubes is a bigger issue, at the very least you're much more likely to pinch or twist an excessively large tube when installing it... Tube size shouldn't really affect the recommended pressure, though if running low pressures (on a CX bike for example), slightly oversized tubes are recommended...

[mcfee03]

Well in that case I'll stay with the 38c's.

I just had a think- I only ride off road 20-30% of the time. However, I do want to stay fit and already peddling is so much easier on a 29er (opposed to my old 26). How much faster or less effort required (% wise) are would you estimate 38c tires to be over 2.1's?

[caneye]

ok .. rehashing this old thread...

i've recently completed a build of a Kona Rove that fits 700c wheelsets.
I tried swopping in my 29er wheelset and the wheels fit perfectly on the Rove. both wheelsets are QR with 135mm rear.

the issue I have is trying to mount 700c tyres on the 29er wheel. it's been a royal PITA.
Both the 700c and 29er wheelsets are Bontrager wheels.

700c - ETRTO 622 x 17mm
29er - ETRTO 622 x 19mm (Bontrager Mustang)

my problem is not the width, but the apparent diameter of the rim (or the tubeless-ready lip??). i'm not sure why. i mounted a commuting 700 x 35C tyre on the 29er Mustang wheel and the tyre appeared stretched abnormally. the reflective strip did not appear consistent around the rim. In one section, it looked to have been pulled INTO the wheel (i.e. hidden behind the lip of the rim).
same tyre worked perfectly on the 700c wheelset.

i took a second tyre (700 x 40C) which I had used on the 700c wheelset for many months. Tried fitting same tyre on the 29er Mustang wheel and it simply wouldn't fit over the lip. reminded me of my schwalbe Marathon Plus when new.

i took a 3rd tyre (700 x 45C WTB Riddler) brand new. It fits on the 29er Mustang but is again not stretching consistently around the wheel. When i ride on a flat surface, i can feel a bump everytime the tyre rotates over the same section. i'm conscious that it might lead to a blow-out.

Prior to this, on the hardtail, the following tyres fit perfectly on the 29er rim - 29" x 2.2 MTB tyres and a Conti Travel Contact 28x2.0 (622-50) commuter tyres.

surely it cannot be that hard to fit 700 tyres on 29er wheelsets?

[MichaelB]

Can be rim circumference too. Doesn’t take much of a difference to make it near impossible. Some tyre brands are painful as well.

But rest assured, 29er tyres will fit 700 rims and vice versa. Just that some combos are harder than others.

[brumby33]

Finally, 29er rims TEND to have Schrader (car) valves and 700C tend to have Presta (skinny) valves.

Not really. Cheap wheels tend to be drilled for Schraeder valves, better wheels are drilled for Presta.

There's gotta be exceptions to this rule.....my 2017 Vivente has Swiss 545 rims with Schrader valves as it's a touring bike, I don't think Noel would've put cheaper rims on his bikes. these are a dedicated touring rim made to go around the world fully loaded so I don't think they'd be a cheap set.....would they?

brumby33

[10speedsemiracer]

It is possible, have done it. Threw a set of 32mm Vittoria Randonneurs on 29er rims a while ago.

It's sometimes a case of getting lucky with the manufacturer sticking to the ERTRO sizes, both rim and tyre. Some are better than others at this at fitting.

[Duck!]

If the tyres you're trying to fit are wire beads, the locking beads of tubeless rims will give you a hard time.