Woah, am I missing something? 85 PSI at 175lbs sounds crazy low for a 23mm tire, any brand. I'm 135 lbs and I ride my 25mm tyres at 85 PSI!

I would think you should be closer to 110 psi on 23mm at 175lbs.

I would agree that pressure is likely too low. I run ~90-95 in 23mm VCS tires @ 155ish lbs depending on road conditions/surface.

What kind of wheels are you running... specifically, what are the interior and exterior rim widths. HED recommends 80 PSI for heavy riders on their wide wheels. Narrow rims might need to be a lot higher than 85. I am currently 185 lbs. and I am running 80 PSI on HED wheels with a 23mm Continental Attack tire up front. I have hit some pretty harsh stuff with no problems.

Corsa Speed tires are very thin compared to other fast tires. They have a wafer-thin tread bonded to the casing, and the casing is pretty thin and exposed. Jumping over to one of the fast Continental tires with a more traditional one-piece look might give you more impact and flat resilience without sacrificing much performance.

what's the width of the wheels? what's the measured width of the tire when inflated on said wheels?

I'm 165-170 pounds right now and run 90 psi using a 25 mm conti and a 17 mm internal width rim. 85 psi is on the low side for you using a 23 mm tire, but not crazy low if you are using a really wide rim (like a Enve 3.4 that has a 21 mm internal) assuming you were riding on pristine roads.

I'd say riding over railroad tracks does not count as pristine roads though. So you should have either used more pressure or taken it easier knowing you were on the low end.

I could be wrong, but I don't think sealant is meant to seal snake bites, so I don't think adding more sealant will help. My understanding is that the sealant will simply leak out of the snake bite hole, but because there is no matching hole in the tire, the sealant will just continue to move out of the tube and around the inside of the tire casing before likely settling in around the tire bead like it would if you were running tubeless.

Reynolds Strike SLG 2016 model year. While external width is wider at 25 mm. The internal is 17 mm.

I have been riding at the 85 psi for a couple years now. But maybe just lucky until last week end.

I was going by the lower pressure is faster until it’s not theory.

Used some guidance from Silca articles and Michelin graphs in no way am I attributing my crash to them.

Please see post 8

Please see post 7

The tire inflated was 26 - 27 mm. Something like that anyway it was within the rule of 105.

Thanks - sounds right...

Those are pretty decent wheels. 85 PSI is a good target. It may be that you had an impact so great that pressure was not a factor-- you were simply going to flat even if you were running 120 PSI.

I would keep on, keeping on. In fact, you might even consider dropping down a few PSI if you jump to more durable Continental tires. I will be racing Augusta this weekend at 80 PSI on 23mm front and 25mm rear tires.

Thanks. It could be I hit it harder than I meant to. It was the fourth lap of four and I was looking to push hard through the finish.

I will try and test a few different pressures out in the off season, but for now will ride high 80’s to be safe.

I’m 160 and run Conti GP4000s IIs at 105 on my 2016 Strike SLGs. Never had a pinch flat, no issues cornering. You’ve got to run more than 85 unless the road is like a baby’s butt. 85 is too low for that tire/wheel/weight combination.

 I don’t think more pressure in the front would’ve avoided a pinch flat, however, I would suggest riding 90 psi in the front with that tire/rim combo. 85 seems a bit low for your weight and that tire/rim combo unless you’re on terrible roads.
More importantly, best to unload the weight from each wheel as well as you can if you know you’re about to hit a large edge.

Thanks - I am pretty certain I need to go up. I’m willing to sacrifice some speed to reduce the risk of going over the bars again. I do like the comfort from the lower pressure.

Do you find 105 psi rides harsh?

That makes me feel a bit better about my tire pressure. Agree on 90 to be safe.

I did try to unweight. I sat up, was on the bull horns and had scrubbed off some speed. Clearly not enough - that is probably the decision that cost me.

So, still my fault but a decision made in the moment that I have to live with.

"Do you find 105 psi rides harsh?"


I used to pump my tires up to 125 psi and ride about 400 miles every week. Felt smooth to me.

No. 105 is not harsh at all, at least on those wheels. My bike is a QR PR6.

But also understand, my perception of harsh is informed by the old days when we used to run tubies at 150. Thank god we got smart about that!

Also, to the guy who said 105 may not avoid the pinch flat....I can guarantee you that I would pinch flat over a couple of the local roads with rail crossings here if I tried running 85...

Curious how the crash happened. A flat tire alone wouldn't make you go over the bars. Did the tire come off the rim?

IME it's real hard to pinch flat a latex tube. Have you verified that's what happened? Was the sealant fresh? I think 85psi is generally enough for your weight, though if the road was smooth a little more would be faster.

Yeah I could see the bite in the latex.

I rolled on to the rim. I was rocking the bike a bit while trying to get up to speed and just finished making a pass. Before I knew it the rim was on the pavement and it was like I was steering on ice. I hit curb and flipped. Maybe just maybe if I was in the middle of the road I could have gotten back on the bullhorns and stayed up.

That does suck but I don't think you really did anything wrong. Shit happens sometimes. It sounds like in their effort to "improve" the railroad crossing, the organizers might have made it worse.

These type of impact/pinch flat scenarios are hard to plan for when talking optimal tire pressures.. that thing that can get you on one course might not be there on the next...

The one thing to remember for triathlon tire pressures is that your weight distribution can be 60% or more front biased depending on your position. Most all of the rules of thumb for pressure have been based on road position assumptions, or my old school assumption that if a road bike was 60/40 rear and a road TT position was more like 50/50 front/rear that Tri would be the same.. but my more recent experience has shown that Tri positions are way more often than not in the 60/40 front/rear range..

While you aren't likely to be running a larger front than rear tire for aero reasons, you certainly can be running slightly higher pressure.. or go to 25mm tires front/rear at same pressure and take a few mm of additional safety margin, and on those rims with minimal penalty.

Best
Josh

---

http://www.SILCA.cc
Check out my podcast, inside stories from more than 20 years of product and tech innovation from inside the Pro Peloton and Pro Triathlon worlds!
http://www.marginalgainspodcast.cc

I took the liberty of using your data in a couple of online calculators (eg https://goo.gl/QoMv5P and https://oniony.com/cycling/calc/pressure/). I am getting a result of around 100psi front 110psi rear for 192lbs bike+rider