Workshop tales, trials and disasters.
Maintenance tips, techniques and myths.
Technical discussion, description and outright lies
As Jack Nicholson would say... "Don't I feel like the absolute fool"!!
Okay... More reason to save up for a second bike and ensure it's got an appropriate tyre size.
Thanks for saving me from wasting that money.
Here is the latest on my experiences with Fusion 2 tubeless...
I have done about 1500km since fitting the tubeless tyres...
Have been running at 100psi...
have had 3 punctures but no flat tyres...
Although one large puncture did seal itself, it did eventually require a patch to be applied to the inside of the tyre to prevent it intermittently spitting a bit of sealant...I was able to do this at my leisure in the garage...This is the hole...
This afternoon I was warming up for a race and noticed the tell tale white spots of sealant on the frame...I had ridden this morning on wet roads and had likely picked up a piece of glass or sharp gravel...anyway the puncture had sealed iteself and I was able to get to the start line without attending to it further...this is the hole in the rear tyre...
When inspecting the tyre to find the puncture, I noticed a nasty cut in the side wall...I didn't have a spare tyre with me so elected to do the race on the damaged tyre...the race was 36km (I won by the way...yay for me...) and the tyre held up ok...the cut hadn't gone right through...Upon arriving home I removed the cut tyre and fitted a new one...(I had ordered 3 initially just for this eventuality)...this is the cut in the rear tyre...
Fitting the new tyre was easy and only took a few minutes more than a normal clincher...it is the 4th time I have fitted a tubeless and now have the process down pat...I did need the compressor to inflate it...
I found the Fusion 2's to be not as durable as the GP4000S's...but they are classed as a race tyre after all...
They definitely roll well (my perception and comparison with competitors)
Yea I thought the same...the bottom section does look like a cut due to cut threads, but the upper section looks like it may be split which grew from the cut...
Also, I did leave my bike unattended for a few minutes, so it may have been sabotage by my competitors...
+1. What's with the ripples in the top of the tread (both on the cut and the other side) lining up almost perfectly with the cut ? Almost like there was a defect in the tyre moulding. The top-down view also shows a pair of similar ripples maybe 5 mm away (down photo).
Wonder if it's worth emailing to the manufacturer for comment on the possibility that it's a manufacturing defect. 1500 km is a pretty short life for a tyre.
Great photos Emma - hope I'm not trying to teach grandma to suck eggs here.
WombatK - Jerry Garcia, Grateful Dead
There are numerous ripples and weavy lines around the entire tyre and appear to be part of the manufacturing process...I dont think they are a cause of the cut.
After examining the tyre closely once removed from the wheel, there definitely appears to be abrasions around the area of the cut, an indication of nicking the sidewall on a largish sharp piece of blue metal or similar. The top section of the cut though does appear to be a tension split, a result I would say, of the loss of structural integrity caused by the cut...
The tyre was wearing ok and I expect had lots of life left if not for the cut. I will see how the new one goes...
(pics by oldish Canon EOS 300D)
The tube and the tyre would rub against each other and the tube and the rim would rub against each other. I'm not sure to what extent, but rubber against rubber and rubber against rubbery tape could be substantial; I don't think the claims of 12% reduction in rolling resistance seem unreasonable given this.
Well, I finally pulled my finger out and fitted the tubeless to the race rear yesterday. What a PITA!
First off, the tape only just fitted into the rim (Velocity Deep-V) between the retaining lips. I ended up with one small section with the tape over the edge of the lip, and had to trim the tape with a knife tip.
Then, I couldn't get the tyre on with the valve stem in place. I had to mount one side of the tyre, get the valve stem in, mount the other side and then pull the stem down into place. The one good thing - instant tyre seal, and I was able to inflate with the floor pump.
The valve stem had a persistent leak - I even unmounted the tyre and R&R'd the valve without success - but once the sealant was in it stopped leaking. As of this morning, when I put it away, it was still fully inflated.
Only nine days until the next race.... hopefully. I'm feeling a bit second hand today, and swine flu is on the loose in our building.
I ride, therefore I am.
...real cyclists don't have squeaky chains...
Does anyone have any updates to this thread? I've just ordered the gear so I can test myself, mainly because I love tinkering with bike stuff in the garage but I have DNF two races this year due to pinch flats. They were days when I knew the roads would be bad and didn't want to risk puncturing a tubular so I was using clincher wheels. Probably should have just run the tubulars as they are much harder to pinch flat but this might be a good option if its reliable.
I am still running tubeless front wheel on Ksyrium SL...have been for over two years.I only race on it so it does about 400-600km per month...this front has been on for maybe 3 months.I can't run a rear as I am using Open Pro rims and they are a PITA to seal.
On the pinch flats...I run 110psi in a Michelin Pro Race 3....weigh nearly 110kgs with bike and race on the roads which can be pretty crappy...I have had one puncture in a race this year (faulty tire)...so as much as I would like a tubeless rear it isn't really an issue.
Our roads are probably a lot worse than yours (north qld). All the pinch flats were a result of hitting things of course - one was pretty big rock and the other was a pot hole. The pot hole incident actually cut the tyre - but it was a Vittoria Diamonde? (Think that is the right name) and I've founded them particuarly easy to damage.
Seems like its worth a test - front really isn't much of an issue because most punctures are the rear.
If you are guarding against pinch flats - tubeless is definitely the go. For glass protection, I just run the sealant in a tube with a removable valve. I've done a TT and a road race on the tubeless rear now, I can't say I've noticed a difference compared to using the ProRace 3.
I ride, therefore I am.
...real cyclists don't have squeaky chains...
Had my fourth puncture (since fitting the tubeless tyres in May 2009) on Sunday while descending a 13km (4% 530m) very winding, at times rough and reasonably fast hill, but once again it didn't result in a flat tyre. It was the front tyre but I didn't even know about it until I reached the bottom of the mountain and saw the spits of sealant on the head tube and down tube. It wouldn't have been nice to have the front tyre deflate at 60kph with a 30 metre vertical drop into the scrub on every corner...
It was only last week I thinking to myself 'I haven't had a puncture for over 1000km'...anyway, didn't add any air and the tyre is still inflated this morning. Hopefully like the previous puncture in the front tyre, it wont require any further attention.
Sounding promising, I used SLIME to repair a tubular earlier in the year - the first decent bump I hit and the tyre failed on the previous cut. It did deflate slowly (I was doing about 70km/ph when I caught the edge of a pot hole) - it didn't re-seal though and I got this purple slime crap sprayed all over me and the bike. I'm still finding slime spots on the bike 6 months later.
Rode 30km home on the rim which was probably something you wouldn't get away with using a clincher Note to self - carry a spare tyre if you decide to do a training / test ride with tubulars....
I haven't used 'slime' but the Stans sealant is easily removed from frame etc with just a wipe with a cloth...a wet cloth would be even better but not essential...it is easy to remove from hands or tyres with water...it doesn't really seem to set or dry out. I have a bit of left over Stans sealant in a measuring cup that has been out in the air for about 6 weeks and is still liquid.
Are you running notubes in your pro race 3s or are they tubed ? can you run no tubes on anything but the hutchinson tyres ?
Peugeot Iseran - Geared Bike
Peugeot Versailles - Fixie
Peugeot U08 - Poser
Repco Nishiki - Single Speed
Just running the michelin normally with a tube..no sealant.
You can only run Tubeless with a tubeless specific tyre on a road bike...there are 2 or 3 different makes now.
I received this info recently on another tubeless system...
I have a pair of XM819's that were run with stans for 4 years, no rust.
The Ammonia angle sounds similar to 97% fat free foods that are 80% sugar.
If all the sealant is foamed up, then it follows that there's less against the inside of the tire so you would be required to increase the amount of sealant required i.e. more weight.
They talked about the pooling being a bad thing - when it's intended. Also Stans has solid bits in it to seal large holes, foam on the other hand has AIR in it - I don't see that being an advantage. I think perhaps the foam thing may be exaggerated as marketing just to separate it from existing products.
Okay peoples, so my kit arrives today.
I've decided to go tubeless on a set of 50mm carbon clinchers as a test case.
I remove the rim tape, put 2 lays of the yellow tape on which by the way doesn't stick very well to carbon (I did clean it first with metho and the wheel is new).
Grab my valve which is 42mm - too short. Remove the stem, fit some valve extensions, stick it through the rim.
PROBLEM. The valve extension doesn't have thread on it for me to screw the thing that holds the valve in place.
Anyone have a solution to this?
I need either a 80mm tubeless valve or an extension with thread on it so I can put the screw thing on to stop the valve from falling into the rim.
Tinkering time over for today....
Sorry cant help on that one...what I will say is once the tyre is inflated you could happily take the valve retainer off (not that you would).Maybe a super tight O-ring?.
I think the screw on retainer would be the only reliable solution.
If you put say a rubber plug in the rim that jammed the valve into place I don't think it would work because the clearance would be too tight and I'm not about to drill a bigger hole in the rim.
I wonder how far the internal thread of the valve extender goes...If it went say 15mm or so, one could cut it off at that point and use it as a bush...screw it on the Stans valve stem and then cut a long valve stem off an old tube (clean up the thread) and screw it into the bush. (Remember to use plumbers tape on the thread.)
Of course you would need to use an old tube that had a removable core so you can squirt the sealant in, or maybe even just pour the sealant into the tyre before mounting the final few centimetres of the tyre.
If the extender internal thread isn't long enough to use as a bush, it may be possible to use a tap to extend the threaded section, or maybe obtain a piece of aluminium pipe of the correct diameter and tap a thread into it to create your own bush.
Both these methods would also give the advantage of having the actual valve exposed and not hidden in the deep rim cavity.
I am assuming the extra width of the bush wouldn't prevent the valve from fitting through the valve hole in the rim.
I just meant a super tight oring to be put onto the valve extender...once there is air in the tyre the pressure holds it in place.
Maybe Emma's idea would work but you would need a fair bit of thread inside the extender....and might be tricky sealing it.
Other option is just to take the valve extender somewhere that they could chase a thread otno it...shouldn't be to hard to run a tap over it.
Getting too hard.
I might chuck them on my windy-day race wheels which are about 26mm alloy rim and test them on those. At least then I'll know if the effort of making a valve extension would be worth it. I think the only way to do the extensions would be to get someone to turn them up. I want the valve at the end though so I don't have to leave the valve undone as this might be a problem with the goop leaking.
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