Giant PXC2 27.5 rims setup tubeless with Bontrager Rhythm rim strip?

Boom King

downloaded a pic of moorey's bruised arse
So here's the rub though. I'm probably around 105kg loaded on the bike and have found that I need around 32-35psi on the rear for the tyre to stop feeling 'washy' during cornering - I'm sure there's a more technical term. At that pressure, I don't really have any rim strikes and have never pinch-flatted on trails which are reasonably rocky. Is tubeless really going to work for my weight with those rims and tyres?
The beauty of tubeless is the ability to run lower pressure and generate more grip. I don't think your weight is the issue, I reckon the problem is the Nobby Nic. I didn't like them at all when I ran them briefly.

With your current setup, there probably is no real benefit to going tubeless.
 

Nambra

Definitely should have gone to specsavers
The beauty of tubeless is the ability to run lower pressure and generate more grip. I don't think your weight is the issue, I reckon the problem is the Nobby Nic. I didn't like them at all when I ran them briefly.

With your current setup, there probably is no real benefit to going tubeless.
That's the conclusion I sort of came to a while back. I just need to abuse my PXC2s now so I can justify a wheel upgrade with the boss, along with pikes, 1x11 and so on. The Kool-Aid is good stuff.

The Nics are 2.25" which according to the post 2007 ETRTO specs are ok to run on 19mm bead width rims like the PXC2's (they came stock on the bike after all). I've also seen ETRTO tables that say this:
308975d1441377065-tire-blow-offs-what-your-experience-etrto.jpg
I'm guessing that is explained by a statement on the Schwalbe website:
"Since 2006, the combination of extra wide tires and narrow 17C and 19C rims is officially approved by ETRTO. This just caught up with reality, because this combination has already been an every day occurrence in MTBs and Balloonbikes for many years and has not caused any problems."

In reality though, wider tyres on narrow rims is probably a combination only suited to lighter riders. There are probably better tyre choices for the narrow Giant rims that would also help; Schwalbe seem to be soft and tear apart fairly quickly in my limited experience.

Appreciate the feedback in relation to my weight too ;). I'm working on getting it lower... another 10kg would be ideal but that means a lot of sacrifice and breaking my Sierra Nevada Pale Ale addiction.
 

stirk

Burner
That's the conclusion I sort of came to a while back. I just need to abuse my PXC2s now so I can justify a wheel upgrade with the boss, along with pikes, 1x11 and so on. The Kool-Aid is good stuff.

The Nics are 2.25" which according to the post 2007 ETRTO specs are ok to run on 19mm bead width rims like the PXC2's (they came stock on the bike after all). I've also seen ETRTO tables that say this:
View attachment 324968
I'm guessing that is explained by a statement on the Schwalbe website:
"Since 2006, the combination of extra wide tires and narrow 17C and 19C rims is officially approved by ETRTO. This just caught up with reality, because this combination has already been an every day occurrence in MTBs and Balloonbikes for many years and has not caused any problems."

In reality though, wider tyres on narrow rims is probably a combination only suited to lighter riders. There are probably better tyre choices for the narrow Giant rims that would also help; Schwalbe seem to be soft and tear apart fairly quickly in my limited experience.

Appreciate the feedback in relation to my weight too ;). I'm working on getting it lower... another 10kg would be ideal but that means a lot of sacrifice and breaking my Sierra Nevada Pale Ale addiction.
I know people in the 100kg range and they run tubeless without issue. Chuck on a set of burly tyres like an exo TR high roller and I think you could run lower pressure without a squishy 'washy' feeling. Throw the schwobble in the bin.

I believe the narrow ID of the rim contributes to the washy feeling of lower pressures compared to a wider rim set up so time for new rims too! If you need to sell it to the minister of finance say its for your safety as your old tech rims are not suitable for modern tyres ;)
 

Mywifesirrational

I however am very normal. Trust me.
So here's the rub though. I'm probably around 105kg loaded on the bike and have found that I need around 32-35psi on the rear for the tyre to stop feeling 'washy' during cornering - I'm sure there's a more technical term. At that pressure, I don't really have any rim strikes and have never pinch-flatted on trails which are reasonably rocky. Is tubeless really going to work for my weight with those rims and tyres?
By loaded do you do you mean 2 pies prior to riding :)

I agree with the others, the tyre is the problem, I"m about 110 at the moment and running 22psi in the rear, on a slightly wider rim, the Nobby Nic is terrible for squirm, if its a schwalbe it needs to be a super gravity or pretty much any Maxxis Exo solves the problem.

It'll blow you mind going tubeless with better tyres and 5-6psi less, the performance benefits / traction are immediately noticeable.
 

Nambra

Definitely should have gone to specsavers
By loaded do you do you mean 2 pies prior to riding :)
There's my Friday funny right there... love a good pie I have to admit but it's usually just my water and tools/spares load that get me over three figures.

Bugger, you've got me wanting a pie now...


I know people in the 100kg range and they run tubeless without issue. Chuck on a set of burly tyres like an exo TR high roller and I think you could run lower pressure without a squishy 'washy' feeling. Throw the schwobble in the bin.

I believe the narrow ID of the rim contributes to the washy feeling of lower pressures compared to a wider rim set up so time for new rims too! If you need to sell it to the minister of finance say its for your safety as your old tech rims are not suitable for modern tyres ;)
So what sort of maximum size should I be looking at on 19mm rims? I honestly can't see a new set of wheels in my near future; the wife doesn't like kool aid, and I'll probably have to take a knife with me on the next ride and slash my tyres to justify new rubber, so I'm stuck with trying to optimise the current setup. Maxxis seem to be the perennial choice and easier on the pocket than Schwalbe, sale prices excepted.

Is this the sort of thing you had in mind: http://www.pushys.com.au/maxxis-high-roller-ii-27-5x2-30-650b-exo-tr-mtb-tyre.html? Run them front and back?
 

Mywifesirrational

I however am very normal. Trust me.
Is this the sort of thing you had in mind: http://www.pushys.com.au/maxxis-high-roller-ii-27-5x2-30-650b-exo-tr-mtb-tyre.html? Run them front and back?
That's a great tyre front or rear, if going front I'd be inclined to spend a bit more for the 3C version, it does grip a bit better.

In the rear also a great tyre traction at the expense of rolling resistance, if thats an issue, something like a tomahawk on the rear might be better, or either a Minion SS.

I am biased though, running a HR2 3C exo front and a Tomahawk rear.

http://www.pushys.com.au/maxxis-high-roller-ii-27-5x2-30-650b-3c-exo-tr-mtb-tyre.html
http://www.pushys.com.au/maxxis-minion-ss-27-5x2-30-650b-exo-tr-folding-mtb-tyre.html
http://www.pushys.com.au/maxxis-tomahawk-27-5x2-30-exo-3c-tr-folding-mtb-tyre.html
 

Nambra

Definitely should have gone to specsavers
That's a great tyre front or rear, if going front I'd be inclined to spend a bit more for the 3C version, it does grip a bit better.

In the rear also a great tyre traction at the expense of rolling resistance, if thats an issue, something like a tomahawk on the rear might be better, or either a Minion SS.

I am biased though, running a HR2 3C exo front and a Tomahawk rear.

http://www.pushys.com.au/maxxis-high-roller-ii-27-5x2-30-650b-3c-exo-tr-mtb-tyre.html
http://www.pushys.com.au/maxxis-minion-ss-27-5x2-30-650b-exo-tr-folding-mtb-tyre.html
http://www.pushys.com.au/maxxis-tomahawk-27-5x2-30-exo-3c-tr-folding-mtb-tyre.html
Thanks for the recommendations, I remember looking at those Tomahawks on CRC a while back, they look like they wouldn't roll very well but obviously they do. The angular tread pattern looks pretty funky too.

I'm a poor rider at best, but even I can feel the difference between the Ralphs on the XTC and the Nics on the dually. They might be ok for a lighter rider perhaps.
 

Boom King

downloaded a pic of moorey's bruised arse
I'm a poor rider at best, but even I can feel the difference between the Ralphs on the XTC and the Nics on the dually. They might be ok for a lighter rider perhaps.
Nobby Nics are the shittest tyre around!

I use a Maxxis High Roller 2 Exo front with a Maxxis Ardent Exo rear, I like the combo. Many around here don't like the Ardent but it works for me.

The Tomahawk is only available in 3C which for a rear, will wear quickly. The new Aggressor looks like a nice rear option in dual compound.
 

4wdphil

Likes Bikes
Tubeless solution to PXC2s

Re-hijacking the thread back to the original topic! I tried the velocity tape (25mm wide) and completely screwed it up. I found it incredibly difficult to push it down into the depths of the rim without it folding or bubbling so it failed to hold any air. A mate of mine has done it successfully though, he had the wheels on the bike and someone holding the brakes on while partly stretching the tape onto the rim and then pushing each couple of centimetres on with a small screwdriver end. Took about 30 minutes per wheel!

So I went to Gorilla tape instead. I struggled to find a really good guide to this so thought this might be useful to others. I've done it on three wheels now and it seems to be holding over the last month, can't guarantee it beyond that (or guarantee it at all for your application!). Anyway, here's what I did and I hope it's of use to others.

Giant PXC2 tubeless conversion
Needed
Tyre levers
Methylated spirits
Clean rag
Gorilla tape 26mm (1 inch wide) . In Australia, Masters Hardware stores normally have this.
Tubeless valve stems
A tubeless ready tyre will also help if your original tyre is non-tubeless.
Tyre sealant (Stans, Joes, Café Latex etc.)
Step 1 – remove the wheel from the bike and the tyre and tube from the wheel.
Step 2 – remove the existing blue rim strip, to get it started you may need to get a tyre lever under it.
pxc9.jpg

Step 3 – Use methylated spirits and a rag to thoroughly clean the inside of the rim.
pxc8.jpg

Step 4 get your 26mm wide Gorilla tape and start sticking it onto the rim on the opposite side to the valve hole. This is the critical part of the operation, you must get the tape centred within the rim first because there are only a couple of millimetres extra. Secondly you must ensure that it’s stuck completely onto the rim with no air bubbles under it.
pxc6.jpg
pxc10.jpg

To do this you need to stretch it slightly and push it into the deeper part of the rim. I went through doing about 10cm lengths at a time pressing it down with the end of a tyre lever all the way around the rim. Overlap the other end of the tape by about 20cm
pxc5.jpg
Finally work back around the rim pushing the tape into the upper parts of the rim profile, again ensuring that it’s properly stuck down without any bubbles.
pxc3.jpg
Step 5 – Once the tape is absolutely fully stuck down all the way around, then take a small Phillips head screwdriver and push it through the tape to open up the valve hole. Don’t clean up all the tape around this hole as the extra tape should help it seal better.
pxc2.jpg
Step 6 – take the new tyre (or original tyre if you’re re-using it) and tube and install it as you would normally. Inflate it to 40psi or the maximum pressure of the tyre. The purpose of this is twofold, to further press the tape onto the rim and, if it’s a new tyre, to straighten out the bead in preparation for it to inflate tubelessly. Leave this overnight.
pxc11.jpg

Step 7 – Deflate the tube and remove one side of the tyre only, try not to break the seal that has formed between the tyre and rim on the other side of the tyre. Remove the tube. Take the tubeless valve stem and install it into the hole. Tighten it up reasonably tight but it doesn’t have to be screwed super tight (overtightening may actually pull the valve stem through the valve hole).
Step 8 – Add sealant to the inside of the tyre before installing the other side of the tyre onto the rim. The correct volume for your size tyre should be written on the label of the bottle of sealant.
Step 9 – Inflate the tubeless tyre. This can be the most complicated part of the process and there are many many webpages devoted to the process which you should check. The important parts are to: use soapy water to lubricate the points of contact between the tyre and the rim, this helps the tyre bead to ‘snap’ into place properly; have a good high volume floor pump or compressor that is able to deliver a strong sustained surge of air into the tyre; once the tyre does start to inflate don’t stop pumping until it has reached a pressure of 40psi; once there is 40psi in the tyre pick it up and hold it horizontally and shake it to ensure that the sealant spreads over all the places where there is a gap between tyre and rim or holes in the tyre. Note that there will be some loud bangs as the bead snaps onto the rim during the inflation process, this is normal. Again though, you should check online for more information on inflating tubeless tyres.
 

teK--

Eats Squid
a few things to ensure almost failsafe conversion every time

1. scrub the rim with scotchbrite (only if u have alloy rims).

2. clean with alcohol

3. Fit tape stretching tightly and with around 1/4 circumference overlap past the valve hole. width of tape should go up the sidewalls slightly so when the tyre is installed the bottom of the tyre bead is sealed completely by the tape. also stops the bead peeling off the tape edge when you remove tyres in future.

4. ** install a standard inner tube and inflate to 30psi or more and then leave overnight to squash the tape down firmly **

5. remove tube, fit tubeless valve, add sealant, inflate.
 

northvanguy

Likes Dirt
Been using this for 2 years now, everything else is overpriced compared to it. Used to be able to get it in 19mm awhile back as well.
How did you manage to get the tape to play nice with the dip in the rim?

I find the tape doesn't 'bend' width wise enough so I've got a massive air pocket below the tape and between the nipple holes.

That's fine but then gettig a nicr tight fit at the valve is hard because it either 'floats' on the tape or pulls on the tape creating a bad seal.

Pretty sure all my sealant has run into that air space...

Any help from anyone appreciated
 
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