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> Tubeless with presta
daniel_owen_uk
post Apr 2 2009, 08:52 AM
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Looking to go tubeless (ghetto) soon, but wheels will only take presta valves, can you get presta tubes with removable cores?
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Jarl
post Apr 2 2009, 10:49 AM
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Drill the wheels. Presta is rubbish tongue.gif


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daniel_owen_uk
post Apr 2 2009, 10:55 AM
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Seems to be the general concensus.

8mm isn't it? Any specific method, or just sharp bit and wack it through?
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Jarl
post Apr 2 2009, 11:10 AM
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yup, 8mm. Drill from the inside out. There was a post referencing by Gareth (I think) to some funky tapered drill bits which were apparently really good for drilling these types of holes, though I can't remember what they were called, so I suspect a search will be a bit of a lost cause.


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daniel_owen_uk
post Apr 2 2009, 12:14 PM
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When you say inside out, you mean from the spoke side to the tyre side?

Wouldn't that leave sharp edges on the tube side?
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rickos
post Apr 2 2009, 12:46 PM
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Hi,

Schwalbe do tubes with removable presta cores.

Rick
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Doug
post Apr 2 2009, 01:57 PM
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QUOTE(daniel_owen_uk @ Apr 2 2009, 01:14 PM) *
When you say inside out, you mean from the spoke side to the tyre side?

Wouldn't that leave sharp edges on the tube side?

Inside as in the bit that is inside the tyre under normal use. wink.gif


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daniel_owen_uk
post Apr 2 2009, 02:02 PM
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Not the bit that's inside the rim smile.gif
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Jarl
post Apr 2 2009, 02:07 PM
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lol, very confusing. Drill towards the hub wink.gif


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Tony F
post Apr 2 2009, 02:08 PM
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QUOTE(Jarl @ Apr 2 2009, 11:49 AM) *
Drill the wheels. Presta is rubbish tongue.gif


What he ^ said. Be prepared to spend a bit of time taking those rough edges off after you've drilled them. I also recall Gareth posting on this, and seem to remember something about drilling them in reverse think.gif .

Gareth?


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daniel_owen_uk
post Apr 2 2009, 02:12 PM
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I would image drill hole, switch drill to reverse, pull out.
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Petty Vagrant
post Sep 30 2009, 05:49 AM
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Why are Presta rubbish?

I'm so sick of getting punctures from thorns as I'm spending a lot of time cycling around woods. I'm thinking of going ghetto (hadn't even heard of it until 2 nights ago when I read about it on here - such a great resource this forum is turning out to be!) but I'm really reluctant to start drilling my new rims.

I've been on JRA, have compiled a shopping list (which includes 20" presta Schwalbe tubes) but haven't hit the 'buy' button yet as I'm still reading up on all the posts here.

BTW - I' riding Alex Rimms DP17 with Kenda Small Block Eight 2.1. Will these be any good for going tubeless with? - sorry for sounding like a dipsh1t newbie but that's what I am!


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Chris M
post Sep 30 2009, 07:42 AM
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If I can just jump in on this quickly as well please wink.gif

Isn't there a risk of weakening the rim by drilling it if it was designed for Presta?

Cheers

Chris smile.gif


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Jarl
post Sep 30 2009, 08:56 AM
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Depends on the rim. Very thin XC race rims (or, roadie rims) won't take well to being drilled. Wider rims shouldn't have an issue. That said, I seem to have a knack of breaking bits of my bike- my rear wheel cracked at the valve hole and I never touched it with a drill, so if you're doing "extreme" stuff, then I'd recommend not drilling. Making sure the edge of the hole is smooth is the best way to prevent damage.

Basically, look at your rims, and imagine an 8mm hole in them. Does that look like it'll work?

Presta are rubbish because they break if you pump them up without being hideously hideously careful.


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Rod
post Sep 30 2009, 09:24 AM
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If your rims are narrow it would weaken the wheel but by how much.
Personally I would not drill *17 rims.

However you can get prestas with removable cores as previously stated. You only need to remove the cores to make the topping up of fluid easier / more reliable but you can top up by pushing the tyre off the rim but that may not seal back up effectively?

Presta vs Schrader:

Presta : hate the stuuuuuupid dozy ropey and most of all WEAK design. Once changed one out and on pumping up the other I removed the pump and the end of the Presta came with it... tyre deflates immediately.

The advantage it that getting to high pressures is relatively easy in comparison to Schrader.

Schrader:
More robust
More available
Easy to pump up with my friend the compressor
why would mountain bike tyres need high pressures anyway?
Oh, removable cores

Rod


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Chris M
post Sep 30 2009, 01:40 PM
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Thanks guys agree.gif

Actually the rims in question are lightweight XC ones so it may be best not to drill them.

Do the removeable core Presta's work Ok for Ghetto? And, do I need to get the threaded ones with the lockring?

I don't actually mind Presta now TBH. I hated them to start with, but having run a road bike for a couple of Years now I don't get problems with breakages any more.

Cheers

Chris smile.gif


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Jarl
post Sep 30 2009, 07:47 PM
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QUOTE(Rod @ Sep 30 2009, 10:24 AM) *
The advantage it that getting to high pressures is relatively easy in comparison to Schrader.


Why would the valve make a difference to this?


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torihada
post Sep 30 2009, 09:11 PM
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I run ghetto tubeless with schrader (cheap 20" mtb tubes) on the HT and on the FS, bonty tubeless with rim strips and removeable core presta valves. I have seen the cack handed doh.gif break their valves, you just need to treat the valves with care when you're pumping. If you're having to pump like a serial flasher at a nudist camp, you either need to buy a larger capacity pump or try some CO2. Using a pump with a connector (flexible hose) rather than connecting directly to the valve can help save you from broken valves. CO2 might be the answer for trail side repairs on ghetto anyway; I recently flatted a ghetto on a 2 " nail. Repaired the hole with a tubeless kit, but couldn't get the tyre re-inflated with the trail side pump. CO2 might've been the answer.


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Rod
post Sep 30 2009, 11:29 PM
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QUOTE(Jarl @ Sep 30 2009, 08:47 PM) *
Why would the valve make a difference to this?


I've heard it said / read that the pin on the presta gets physically pushed in by the pump adaptor. This way you don't have to overcome the air pressure against it before air goes in. However, air pressure being air pressure and all values being equal for a given for a cross-sectional surface area... I personally don't know about this theory. I suggest it is down to the sectional area of the aperture? I've not done the calculations but I guess the sectional cross section is about twice that of the presta in the Schrader? This in turn means there is less psi presenting to the inlet making it easier for a given pump to excert enough pressure to blow past the schrader valve or go down the throat of the presta.

BUT I guess you are going to tell us all anyway? biggrin.gif

Rod


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Chris M
post Oct 1 2009, 05:44 AM
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So, just to summize for the hard of understanding here (i.e. me :oops )

As long as I'm happy to use Presta valves, then there's no real reason to drill my rims to accept Scraeder as long as I buy some 20" tubes that have Presta valves with removeable cores ?

Saying all that, my rims came ith 2.35 tyres as standard so they may well be wide enough to drill without any issues. But, I can't see the point of doing it if the only problem with Presta is the fragility (which doesn't worry me personally.) Or, have I missed something?

EDIT: I suppose there's the issue of the initial seating of the tyre, i.e being able to use a garage airline, but wouldn't a Presta-Schraeder adapter get over that one?

Cheers

Chris smile.gif


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