Street Trials, tubes, tubeless or tube + insert?

[Rip]

So, front wheel definitely has a leak around the valve, no idea why because I've tried finger tight, spanner tight (nipped up) and everything in between. and both wheels seem to be leaking through the tyre carcasses themselves, the tiny bubbles reappear after wiping them away.

 

So, obviously the one with the leak around the valve needs a complete do-over. Is it worth painting tyre sealant (or some other flexible type sealant) around the inside of the tyre carcass and letting it dry a little before installation? And not sure about the other one, I'm wondering if the sealant can't get around to everywhere to seal the tyre carcass because the Rimpact insert is in the way, maybe I need to take the Rimpact insert out and set the whole thing up giving the sealant the room it needs to do its job while riding the bike (i know rising is the key part here because the sealant has to be flung everywhere as the tyre is flexing about, just wondering if the Rimpact is hindering this process), then make sure it's not leaking and THEN disassemble it all again and stick the insert back in?

I'll stick a tube back in the front as that ones terminal because of the leak around the valve and I'll keep riding the bike as much as I can and hope the Stans will eventually seal the tyre carcass which it should do given enough time, after all it's designed to seal bigger holes quickly not microscopic holes. 

If that doesn't work for any reason then I think I may have to call this another fail for now because it's the time of year where I want the bike useable at any given time due to the weather so maybe this needs doing over the Winter with yet another set of new tyres, a big ol' tub of sealant and a lot more crappy weather. Noticed here that Duncan Shaw uses the Continental CompactWide inner tubes apparently, either that info is incorrect, he gets a lot of punctures or those tubes are pretty decent so maybe I'll just stick those in for the remainder of this years riding season.

 

Edited May 10, 2021 by Rip

[Rip]

I'm calling it a fail for now, again. Since being filled with Stans sealant they've been pumped up about 40 times, shaken, spun and tipped at all sorts of angles and ridden on for about 3hrs total (a mixture of normal riding and all manor of hopping about) and they still both go completely flat over night. Even though the beads never seated properly they can still be initially pumped up with a normal track pump and do hole air for a number of hours but they are clearly slowly leaking around the valves and also somewhat through the tyre walls, if it was just the tyre walls I'd probably preserve with it a bit longer as they should eventually seal up after more riding but I feel like I'm fighting a losing battle with the leaks around the valves. 

I'll revisit this again in the winter with another set of new tyres and probably get the carcasses sealed up fully before installing the Rimpact inserts as  convinced they are hindering the sealing process somewhat. 

In the meantime I'd like to find some Schrader tubeless valves that would work nicely with tyre inserts if anyone knows of any? None of the ones I've seen have any kind of cross drilled hole at the bottom or any kid of protrusion that will stop the foam insert from from blocking the valve. The Rimpact valves have a hole drilled across the end to allow the air to come out sideways and I reckon if I just used any old Schrader tubeless valve I'd have trouble getting air in. If I can't find any then I'll have to come up with a device that keeps the insert away or cut a notch out of it. 

 

Also, I notice a lot of the 20" mod boys you see on YouTube don't run Tubeless yet somehow also manage big drop gaps to super sharp edges without getting punctures, how?

Edited May 12, 2021 by Rip

[Swoofty]

1 hour ago, Rip said:

Also, I notice a lot of the 20" mod boys you see on YouTube don't run Tubeless yet somehow also manage big drop gaps to super sharp edges without getting punctures, how?

Wider rims. A wider rim offers fewer points to cause pinches. The available 24" rims don't really give you that option and for street trials would make the tyre profile more 'square'.

[Rip]

33 minutes ago, Swoofty said:

Wider rims. A wider rim offers fewer points to cause pinches. The available 24" rims don't really give you that option and for street trials would make the tyre profile more 'square'.

Interesting. 

[Ali C]

As far as I know there’s no schrader valves designed for inserts. I’ve used normal valves with inserts before and the issue isn’t getting the air in but more getting the air out as the insert presses on the valve...I fixed this in the past by stabbing the insert with a spoke through the valve to give passage for the air.

 

 There is a way to use presta valves on a schrader rim though... you might find my video this Friday quite interesting   

[Rip]

8 minutes ago, Ali C said:

As far as I know there’s no schrader valves designed for inserts. I’ve used normal valves with inserts before and the issue isn’t getting the air in but more getting the air out as the insert presses on the valve...I fixed this in the past by stabbing the insert with a spoke through the valve to give passage for the air.

 

 There is a way to use presta valves on a schrader rim though... you might find my video this Friday quite interesting   

Thanks for the tip, and I'll look forward to this week's video even more then  I'm determined to earn the right to stick my Rimpact stickers on my bike at some point!

[Swoofty]

7 hours ago, Rip said:

I'm determined to earn the right to stick my Rimpact stickers on my bike at some point!

I think you've tried hard enough to make this work that you've earned those stickers.

[Rip]

4 hours ago, Swoofty said:

I think you've tried hard enough to make this work that you've earned those stickers.

[Mark W]

16 hours ago, Swoofty said:

Wider rims. A wider rim offers fewer points to cause pinches. The available 24" rims don't really give you that option and for street trials would make the tyre profile more 'square'.

The rim width is certainly part of it, but the overall tyre design plays a big role in it.

In terms of Presta valves in Schraeder rims, that's how I've had a few bikes set up (including with Rimpact valves...) for a while and I've never had any problems with it. The tapered base means that it doesn't really come into it. If you've sliced a big hole in the rim tape for the valve to go through that might not be helping. If you've got a leak elsewhere in the rim tape that can also manifest itself through the valve hole, although that sounds like it shouldn't be the issue with yours... If the tyre is super tight to fit and they've used tools to fit it it could be that the tape was nicked/damaged, maybe?

It's weird to see the tyres are leaking that much air, but as you said it may just be a case of needing to either ride the bike more to get the sealant moving properly, or possibly doing it without inserts at first to let more of a free flow of sealant happen.

On that note, how much sealant was actually used? Has it been measured out at any point or just guessed? You do need to use quite a bit more than normal if you're using inserts, and if the tyre is that porous it could just be a case of requiring more.

[Mark W]

On 10/05/2021 at 4:15 PM, Rip said:

Noticed here that Duncan Shaw uses the Continental CompactWide inner tubes apparently, either that info is incorrect, he gets a lot of punctures or those tubes are pretty decent so maybe I'll just stick those in for the remainder of this years riding season.

That info was correct at the time that was written, but that was a few years ago (that bike is the 2017 Fourplay). He's using a tubeless setup now.

[Rip]

16 minutes ago, Mark W said:

That info was correct at the time that was written, but that was a few years ago. He's using a tubeless setup now.

That makes sense then, I've got some of those tubes now so I'll stick them in until my Tubeless V3 attempt. 

[Mark W]

Forgot to mention before but when I first set my MTB up tubeless, it took a few rides for the pressure to stabilise. As you alluded to before, it does take a bit of time for the sealant to get fully worked around the wheel, and basically shaking it/moving it by hand isn't the same as riding around and letting that force from your wheel's rotation make that shit happen.

[Rip]

23 minutes ago, Mark W said:

Forgot to mention before but when I first set my MTB up tubeless, it took a few rides for the pressure to stabilise. As you alluded to before, it does take a bit of time for the sealant to get fully worked around the wheel, and basically shaking it/moving it by hand isn't the same as riding around and letting that force from your wheel's rotation make that shit happen.

Yes that's what I've read online also, I've done about 3hrs riding and they still go down over night so I don't know if more riding will sort it or not. 

[Mark W]

For my MTB it took multiple 3-4hr rides and some pumping up overnight before they got what I was looking for from them. That said, they didn't go totally flat. When I had a setup that did that it was the one I mentioned before with there being a tiny notch in the rim tape that was leaking air.

[Rip]

Mine definitely go completely flat overnight which I guess is down to the beads never really popping into place and the leaks around the valves. 

[Rip]

It's official, the plug has been pulled on Tubeless V2. Upon disassembly I can see that the bike shop didn't put much sealant in there so maybe that wasn't helping, from what I can see the Rimpact does not soak it up (good thing), at least when I hosee them off no sealant came out of them.

And there was nothing that looked to be of any concern around the valves so not sure why they were leaking?

 

 

Tubeless V3 will commence in the Winter so for now it's down to these tubes and a load of Baby Powder:

 

 

 

 

 

 

 

 

Edited May 14, 2021 by Rip

[Mark W]

Couple of things. Why I was asking about the amount of sealant before is because tubeless setups are pretty simple. If they're not sealing, it can only really be one of four things:

- Your tyre, indicated by sealant coming out from either a hole on the tyre, or from around the bead*.

- Rim tape, indicated by sealant coming out around your nipples or by the valve.

- The valve, indicated by sealant coming out around the valve stem or core.

- The quantity of sealant, indicated by air loss without any of those things I just mentioned.  

Checking them off is a pretty good way of sorting things out. I had a feeling that the amount of sealant may have been part of it. If there's a leak somewhere and you've got plenty of sealant in the tyre, there'll be residue where it's dried or you'll be able to see it bubbling away. The Rimpacts don't absorb sealant, but they do get coated in it so you need 20-25% more sealant than you'd expect for your wheel size to mean that once they've been coated fully there's still plenty kicking around to seal things up, handle business with the tyre until it essentially has a non-porous layer around it, and then seal up any other problems that pop up. I always run quite a bit over the suggested amount in the wheels of my trials bike and MTB because for the negligible weight penalty of having an extra 30ml or so of sealant in each tyre you know that it's going to have plenty to seal the tyre up properly initially, and also have some for if you happen to burp the tyre/cut the tyre/ride over some thorns or glass or something.

The cut in the rim tape for the valve stem looks a bit bigger than I'd normally go for. I generally pierce a really small hole in the tape (usually using something like a 2mm allen key or something), then use the valve itself to enlarge the hole as I push it through. This way you know you've got the minimum possible hole in the tape, giving it the best chance of sealing. As before, it may be worth having a look around the rest of the rim tape to see if there's any issue elsewhere. Once the sealant has got past the rim tape it's hanging out in the cavity of the rim, so it can come out pretty much anywhere it chooses. When I initially converted my old MTB wheels to tubeless, they'd been taped from the factory so I didn't bother adding any myself. Turns out they're done a shit job, so I ended up getting sealant bubbling out through the rim join and random spokes. That all came from one bit of the tape that had gone wrong, but you wouldn't really have known where exactly just from looking at where the sealant was appearing.

 

 

*That is somewhat simplified - if you've got a really porous tyre then you will get air leaking out through that, but that typically won't be much, especially with those Conti tyres. If you've followed the point below it about having plenty of sealant, after a few rides it stabilises and you don't get the same kind of air loss between rides.

[Rip]

Thanks again for the detailed info. I did actually fit the valve how you described above, I guess the cone of the valve maybe enlarged the hole after installation possibly. The lack of sealant definitely bothers me, especially as I was charged extra at the bike shop because they "kept filling it with sealant until no more would go in".

I'll be doing the sealant myself next time so I'll know exactly how much has gone in and maybe I'll also go with proper tubeless tape rather than Gorilla tape, something about the Gorilla tape just doesn't sit well with me, it also leaves lots of glue residue on the rim after removal which is really hard to get off which is something I'll have to do before applying proper tape I guess. Maybe I also need to do what others have suggested and put an inner tube in the wheel after installing the tape and leave it pumped for 24hrs or so to really compress the tape into place. Although that would leave a Schrader valve size hole in the tape afterwards but I also think I might actually use Schrader tubeless valves anyway so that wouldn't matter too much. I think it might also pay to let the tyres seal without the Rimpacts in and then install them afterwards. 

My biggest unanswered questions so far are exactly how wide I need this tape to be? Some people have suggested that full width tape can help the tyre bead pop up into the rim but I'm wondering if on such a tight fitting tyre the tape is actually hindering that process instead. And probably an even bigger mystery to me is why the beads won't pop on properly, I've now tried narrower tape, wider tape, soapy water on the bead and various inflation devices and no combination of those things have resulted in the beads getting seated properly, and like in the photos below the tyres are visibly just not fitting right which results in the wheels looking buckled when spinning and quite a lot of imbalance:

 

This definitely bothers me as it's just not right, last time I used narrower tape and lube on the bead the bead blew off the rim completely rather than seating properly and that was just with a canister type track pump so something seems very wrong about that. They are exactly the same even when using inner tubes, it's like the tyre bead diameters are just too small for the rim diameters so the beads simply cannot go where they need to go. 

While on the subject of the tyres, why does it say 'moped' on my tyre? 

 

 

 

 

 

Edited May 14, 2021 by Rip

[Mark W]

11 minutes ago, Rip said:

The lack of sealant definitely bothers me, especially as I was charged extra at the bike shop because they "kept filling it with sealant until no more would go in".

This is exactly why I really, really dislike a lot of bike shops. That's just flat out bullshit. If you don't do it properly, when you're injecting the sealant through the valve it can start blowing back out of it, but if you're unaware of that and what causes it you really shouldn't be working at a bike shop...

For the rim tape, Cap's school of thought with it was to go just for the rim well, so you're not on the section where the tyre bead sits on the rim. I think part of the reason that it can be hard to seat them is just the shape of the 'shelf' where the bead sits. If you look at it on the Team V2 rim compared to a random other rim, you can see it's a little different. It seems that tyres can get a bit hung up as they get pushed across sideways, so they don't necessarily seat fully against the outer edge of the rim:

I think the diameter of that 'shelf' where the bead sits is different on the latest generation V2 rims which is why Inspired refer to them as being better for tubeless.

On the rim tape, you don't need to compress the tape or anything like that. Just go for any kind of adhesive rim tape and you'll be fine. You're supposed to apply it with a good amount of tension as you roll it off the tape so that it's a good fit to the rim and doesn't have any gaps or air bubbles to let sealant escape. If you've done that, you don't really need to do anything else with it as it's as in place as it's ever going to be.

"I think it might also pay to let the tyres seal without the Rimpacts in and then install them afterwards."

That's a little self defeating in a way as you'll have to break the seal of the tyre to get the insert in. The only real thing I'd suggest as far as that goes is to seat the tyre with no sealant in with the valve core removed, then once that's done let the tyre down, inject the sealant through the valve then reinstall the valve core and pump it up. Taking the valve core out makes a big difference to how easy the process of seating the tyre is.

 

[Rip]

19 minutes ago, Mark W said:

This is exactly why I really, really dislike a lot of bike shops. That's just flat out bullshit. If you don't do it properly, when you're injecting the sealant through the valve it can start blowing back out of it, but if you're unaware of that and what causes it you really shouldn't be working at a bike shop...

For the rim tape, Cap's school of thought with it was to go just for the rim well, so you're not on the section where the tyre bead sits on the rim. I think part of the reason that it can be hard to seat them is just the shape of the 'shelf' where the bead sits. If you look at it on the Team V2 rim compared to a random other rim, you can see it's a little different. It seems that tyres can get a bit hung up as they get pushed across sideways, so they don't necessarily seat fully against the outer edge of the rim:

I think the diameter of that 'shelf' where the bead sits is different on the latest generation V2 rims which is why Inspired refer to them as being better for tubeless.

On the rim tape, you don't need to compress the tape or anything like that. Just go for any kind of adhesive rim tape and you'll be fine. You're supposed to apply it with a good amount of tension as you roll it off the tape so that it's a good fit to the rim and doesn't have any gaps or air bubbles to let sealant escape. If you've done that, you don't really need to do anything else with it as it's as in place as it's ever going to be.

"I think it might also pay to let the tyres seal without the Rimpacts in and then install them afterwards."

That's a little self defeating in a way as you'll have to break the seal of the tyre to get the insert in. The only real thing I'd suggest as far as that goes is to seat the tyre with no sealant in with the valve core removed, then once that's done let the tyre down, inject the sealant through the valve then reinstall the valve core and pump it up. Taking the valve core out makes a big difference to how easy the process of seating the tyre is.

 

Interesting info about that 'shelfs' diameter, that makes total sense as to why I'm having trouble. Maybe these tyres just will not fit these rims properly no matter what, I wonder if my bike (Team edition) left the factory with the tyres actually perfectly fitted all the way round as it would have come with the same tyres (assuming the tyres are actually fitted at the factory and not at dealers).

I definitely had the valve cores removed when trying to seat the beads and apparently so did the bike shop but neither of us were successful.

Next time I'll try tape just across the well in the rim again then so I'm not increasing the rims shelf diameter any more, fit some Schrader tubeless valves or at least some rim hole adapters and apply a lesser amount of soapy water to the beads and of course I'll be in control of exactly how much sealant goes in, Ali C put 140ml of MucOff sealant in during one of his videos about tubeless inserts so I guess I'll go for about the same amount. 

Edited May 14, 2021 by Rip

[Mark W]

14 minutes ago, Rip said:

I wonder if my bike (Team edition) left the factory with the tyres actually perfectly fitted all the way round as it would have come with the same tyres (assuming the tyres are actually fitted at the factory and not at dealers).

Believe the tyres are usually fitted to the rim (not fully inflated though) at Inspired's warehouse, then dealers would do any final checks to the bikes. If the tyres have to be let down for shipping (can't remember if they are with Inspireds) then that can negate that, obviously.

It is possible to get the tyres to seat properly, but with the variation in Conti tyres due to them being relatively handmade it may just be your tyres are a bit harder to fit than others or something.

As before, you don't really need to go for Schrader valves. I've got Presta valves in a Schrader drilled Spank rim on my bike now, I've had Presta valves in other Spank rims drilled the same way, Duncan used Muc-Off Presta valves on his Team rims before he got some Reserves on there, Ben's used Presta on his Inspired rims, etc... It really isn't a problem, that's why the valve stems have such a taper to them. As Ali mentioned before, the faff of non-side drilled valves (which accounts for basically all Schrader valves I'm aware of) being used with inserts far outweighs the marginally improved sealing you might get around the valve stem.

[Rip]

1 minute ago, Mark W said:

Believe the tyres are usually fitted to the rim (not fully inflated though) at Inspired's warehouse, then dealers would do any final checks to the bikes. If the tyres have to be let down for shipping (can't remember if they are with Inspireds) then that can negate that, obviously.

It is possible to get the tyres to seat properly, but with the variation in Conti tyres due to them being relatively handmade it may just be your tyres are a bit harder to fit than others or something.

As before, you don't really need to go for Schrader valves. I've got Presta valves in a Schrader drilled Spank rim on my bike now, I've had Presta valves in other Spank rims drilled the same way, Duncan used Muc-Off Presta valves on his Team rims before he got some Reserves on there, Ben's used Presta on his Inspired rims, etc... It really isn't a problem, that's why the valve stems have such a taper to them. As Ali mentioned before, the faff of non-side drilled valves (which accounts for basically all Schrader valves I'm aware of) being used with inserts far outweighs the marginally improved sealing you might get around the valve stem.

Maybe I've just been unlucky so far with my tyres then as that's 4 I've had now that won't seat. The only reason I mentioned Schrader valves is because the presta ones move around an awful lot in the larger hole when done up to the recommended finger tightness (and also when nipped up a bit tighter too) but I guess that doesn't matter too much as long as they seal, I'm an engineer so I like things locked in place if they aren't supposed to move 

[Mark W]

8 minutes ago, Rip said:

that doesn't matter too much as long as they seal

Essentially, this. I don't really know what you're doing to them to make them move, but like I said before, if the valves were the issue then you'd see sealant bubbling around the base of the valve stem whenever you put air in the tyres. If you aren't seeing sealant there, they either aren't the problem (so you don't need to change them, and can keep using the Rimpact valves which are good) or you haven't got enough sealant (which you didn't).

In terms of valve movement, it's worth remembering that there's a tapered rubber base, and the sealing part under the locknut is an O-ring, so it's never going to be solid. The first tubeless setup I did had Schrader valves and they still moved a little if you wiggled them. The key thing to note here is that you don't need to wiggle your valves  

[Rip]

Just now, Mark W said:

Essentially, this. I don't really know what you're doing to them to make them move, but like I said before, if the valves were the issue then you'd see sealant bubbling around the base of the valve stem whenever you put air in the tyres. If you aren't seeing sealant there, they either aren't the problem (so you don't need to change them, and can keep using the Rimpact valves which are good) or you haven't got enough sealant (which you didn't).

In terms of valve movement, it's worth remembering that there's a tapered rubber base, and the sealing part under the locknut is an O-ring, so it's never going to be solid. The first tubeless setup I did had Schrader valves and they still moved a little if you wiggled them. The key thing to note here is that you don't need to wiggle your valves  

lol, it just annoyed me that they moved when I touched them even very lightly, probably not an issue though like you say. I definitely had a leak around one of the valves... 

 

 

 

 

[Mark W]

16 minutes ago, Mark W said:

...if the valves were the issue then you'd see sealant bubbling around the base of the valve stem whenever you put air in the tyres. If you aren't seeing sealant there, they either aren't the problem (so you don't need to change them, and can keep using the Rimpact valves which are good) or you haven't got enough sealant (which you didn't).

As I was saying  

13 minutes ago, Rip said:

I definitely had a leak around one of the valves...  *Video*

If you're having to use water to find where a leak is, there most likely isn't enough sealant because the sealant would generally direct you to where the issue is.

Just on the valve movement front, I f**ked a ride with a friend at a trail centre by not being the gentlest when I was attaching a pump to my valve (Presta valve, Presta rim) and breaking the seal a touch causing it to have a super convenient slow flat the rest of the day. If the locknut is done up firmly then there will still be a bit of movement and you do need to be relatively careful when doing stuff like adding/removing pressure. Schrader valves won't alter that because they're still a tapered rubber base, it's still an O-ring of some sort, and it's sealing against rim tape at one side of the valve hole. It's never going to be fixed in place.