# Big guy tire pressure



## Steve030687 (Jan 7, 2007)

I am having a problem with my tire pressure. I am a 200lbs. 5'11" quasi-clyde that cannont stop pinch flatting on a 4" Titus Racer-X. I would normally run about 40 psi in the tires, but I can still pinch flat. For a while, I was averaging over a pinch flat a ride.:madman: I am now up to 60psi, but taking a beating on rocky technical single track, but at least I am not spending half of my ride changing a tire(s). I have WTB Velociraptors F/R on DT Swiss 4.2d rims. I used to run Panaracer XC Fire Pro, and they were even worse. I use a whole mix of tubes and none have come back alive. My questions is how many psi do you guys run in your tires? I am really thinking about going Stan's but I have heard some horror stories.


----------



## CharacterZero (May 19, 2004)

What size tires are you running? 2.1?
Have you tried DH tubes?


----------



## SHIVER ME TIMBERS (Jan 12, 2004)

check your rims for any burrs.....

if you are riding rockier terrain you might want to switch 2 ply tires (stonger sidewall = less pinch flats)


----------



## marzjennings (Jan 3, 2008)

I quit using XC type tyres a few years back and I've only running AM/DH tyres now. Sure they're heavier, but I can run lower pressures without risking a pinch flat. For the last year I've been using Maxxis High Roller Semi Slick for riding the local single track. Really great in dry to tacky conditions, very fast and holds well in corners. I'm 225lbs and I usually run under 40psi. 

I just stuck on a set of Conti Petrols and while they are lighter and seem to have good protection against pinch flats (been running them around 35psi) they really suck in corners. I'm ordering a new set of Maxxis. 

laters,

Marz


----------



## Steve030687 (Jan 7, 2007)

Yes, my WTBs are 2.1 tires. It seems that I don't even have to really hit anything that hard anymore, I can just flat out really easily. I have heard good things about the High Rollers. They may have to be my next tire; I was going to try a set of Nevegals. They seem popular enough, how bad can they be?

What is this about 2 ply tires? Who sells them?


----------



## marzjennings (Jan 3, 2008)

I've tried a few Kenda tyres and while they were nice and light, great grip and corning and fast, I thought the side walls a bit weak and I did pinch flat a couple of times. I've not tried their AM or DH tyres.


----------



## taterbug (Jul 30, 2008)

Steve030687 said:


> Yes, my WTBs are 2.1 tires. It seems that I don't even have to really hit anything that hard anymore, I can just flat out really easily. I have heard good things about the High Rollers. They may have to be my next tire; I was going to try a set of Nevegals. They seem popular enough, how bad can they be?
> 
> What is this about 2 ply tires? Who sells them?


Something is wrong somewhere. I weigh about 250 but have been much heavier and right now I am running a Schwalbe Big Betty 2.4 front and a Fat Albert 2.35 rear. I have never pinch flatted and right now run the BB at 32psi and the FA at 35 psi over very rocky and rooted up singletrack. I am however, very light on the bike. I lift the front and back on hard square edged hits and haven't ever flatted even when I was much heavier...300+


----------



## josho (Jan 28, 2008)

I have a 2.5 weirwolf up front and 2.4 mutano raptor rear both between 35-40psi no flats. Try a bigger tire.


----------



## Steve030687 (Jan 7, 2007)

I really do want to try another tire, but I am trying to avoid anything larger than 2.1. Mostly for rotating weight issues, but also I don't think I have that much room in between my F100 RLC or rear swingarm.


----------



## CharacterZero (May 19, 2004)

IMO your tires are too skinny. Bigger guys need more contact patch on the ground, as well as more volume in the tires to cushion against trail features.

Take your weight, divide by 100 and that should be the size you are running if you want to run pressures in the 30s. YMMV when using rims that aren't made for wider tires. I know that you face constraints with forks and rear clearance, it is something that you will have to work around until you get all the variables hammered out.


After having moved to 2.3 tires, I will never go smaller. I am currently running a 2.4 Big Betty UST and an Enduro UST 2.4.


----------



## madcatmini (Aug 3, 2008)

I run a mutano 2.4 up front and a mutano 2.35 in the back at 40 PSI. The tires rock my wheels suck. Rotating weight is one thing but if it's that big a deal just get stronger


----------



## Raphy (Jul 6, 2008)

the tires on my bike says to put 60psi???? im 511 close to 300??? been riding mostly on unpaved flat terrain with the once in a while hills...


----------



## CharacterZero (May 19, 2004)

Raphy said:


> the tires on my bike says to put 60psi???? im 511 close to 300??? been riding mostly on unpaved flat terrain with the once in a while hills...


That is most likely a max pressure, though at your weight I would want to run something around 50psi.
How do they feel? That is the question.


----------



## Kyoseki (Oct 26, 2004)

Agreed, something's wrong somewhere.

Been running Panaracer Fire XCs 2.1 @ 45 PSI for the past couple of years and have pinch flatted a grand sum total of once and I'm 280 or so right now.

... of course that was the one day I didn't have any spares with me (important tip, always remember to repack your Camelbak  )


----------



## jeffj (Jan 13, 2004)

I used to run Velociraptors when I weighed around 240lbs and only had pinch flats if I got below 50psi. I would usually keep them at 53psi and not let them get below 50psi and I would be fine. If they got down,around 45-48psi, I was at-risk.


----------



## Buzzaro (Jan 27, 2008)

As a few people stated above, I think your tires are too skinny. If it will work for you I think a higher volume tire would work great. 
As far as a Stans setup, I just switched to running Stans with WTB weirwolfs (2.55lt ft/ 2.35rear) with zero issues and about 50mi so far.
The 2.55 was a breeze to mount but the 2.35 was a little tougher to get the bead to seat. Once I got it mounted correctly I couldnt be happier and would definately recommend it. Im 225lbs+ using it with standard XC tires at 30psi and pretty sure I can run 25psi if I want.
Ive heard some standard tires have thinner sidewalls and the air will kinda "seep" out of the sidewalls and the sealant cant really seal those very well so you would have to look at that on your tires. I know my WTB's dont have that issue but a friend with Panaracer's said that the sidewalls were too thin. Anyhow, this could be a solution for you if you really want to keep the same tires your running and if you choose to, feel free to PM me and Ill answer any mounting questions if you have any. 
Good luck, flats can be so frustrating and really ruin a good ride.


----------



## slowdave999 (Jul 25, 2008)

im 5'7" and about 200 up to 220 when im struggling (now), i have run 2.1 nevegals at 45 rear and 40 front no problems, i also run crossmark at 45-50 in a 2.0 so far no problems and a conti explorer 2.1 supersonic with stans in the front at 37-42 dont have too many problems. i did get a bit silly and try to run a conti twister supersonic and it flexed and burped the stans goop all over then place. With all that said there are very few rocks in my regular trails.


----------



## Yardstick (Jan 10, 2007)

It sounds to me like you need to focus on riding smoother rather than on tire pressures or sizes. The 4.2d rims are pretty narrow so you might already be at the big end of the tire range running 2.1's.

When I was lighter (~220lbs) I pinch flatted like crazy! I had one day where I totally packed it in after getting four pinch flats in less than a mile. It was partly because of the pressure I ran (~30-35psi) and the tire size (1.9-2.1's), but mostly because I was slamming into things. Upping the pressure to 50psi and switching to Fire XC Pro 2.1's helped a lot for a long time. Recently I've been experimenting with lower pressures. At 40psi I've had one problem in the last year and I can pretty much attribute it to being extra aggressive but not smooth. That's using Motoraptor 2.1's and 28mm wide rims on a 5" air suspended bike. My bigger bike has 2.4's and 32mm rims and so far I've had no issues down to ~30psi. And I'm 265lbs.


----------



## jeffj (Jan 13, 2004)

Lots of 220lb (or larger) guys rode 2.1" tires for years without nearly the issues the OP has mentioned. You do have much better choices these days in larger tires, but he's not 'too big' for 2.1" tires like Velociraptors if that is what he chooses to run.


----------



## savagemann (Jan 14, 2008)

Maybe your pressure gauge is off. = )
I ran 2.1 Nevegals at about 45psi rear and 40 psi front for a long while with 0 pinch flats.
Then I upgraded the front to a 2.35 nevegal. 0 flats.
Just put a 2.35 Excavator on the rear. Seems nice with the 2.35 nevegal front.
While they have a bit more rolling resistance than the 2.1 nev's, it isn't that much more.
When I'm bombing on the streets to and from work I sometimes take the 6" trail bike and have the psi around 50ish. When I hit the trails I drop em to 40 front and 45 rear.
I'm close to 300 lbs geared up with a days ride worth of water, food, tools and extras. I haven't had a flat in over a year.
I am a pretty smooth rider for my size, but I ride pretty hard and like to catch a little airtime here and there.
I wonder if your rims are too narrow? Or possibly have some kind of issue. Maybe the bead on your tires is bad or something.
You're not running lightweight tubes are you?


----------



## Starkonian (Dec 31, 2007)

I'm 220 and run 'raptors in the 2.1 size. I ride rocky single tracks with 32 lbs pressure. I have never had a flat. When I ran 40 lbs the ride was too harsh. I wonder if something is wrong with his rim?


----------



## H3LlIoN (Jul 30, 2008)

I'm running the stock Specialized Enduro Sport tires that came on my Comp, 26 X 2.2. Rated for 50 -80 psi. I used to get mad pinch flats, until I realized that squeezing the tire was not sufficient for judging tire pressure. I check them now before every ride, and I won't leave unless they are at or higher than 60psi. I generally fill them up to 70, then repeat when they bleed down to 60. I beat the hell out of them, and used to get flats from simple bunny hops and stuff like that. I'd generally have a flat every two weeks. Now that I run higher pressure, I'll slam in to a curb by accident, and I'll ride all the way home knowing I'm going to have another flat, but I never do. The more air, the better, trust. The only flat I've had recently was from a construction staple, 9 miles from home. Thank god for buddies with pickups! More air will help too, since your bike will roll easier. 

I just ordered Kenda Dred Tread DTC's rated for 65, and I plan on filling them up at 60. Anyone overfilling?


----------



## beanfink (Nov 22, 2006)

I weigh 300 and I run 2.3" DTC nevegals on my trail bike. I usually go about 47.5psi in the rear and 42.5 psi in front.

I could probably go lower than this on the trails around here, but then I'd have to go out and do a "lower the pressure by 2.5psi each lap until I flat" ride. 

I'll get around to that... eventually.


----------



## Boyonabyke (Sep 5, 2007)

Dude, your rims... 4.2 d's are designed for a maximum of 90kgs.... get some wider rims and not so deep dished, and your problems are solved... or just go tubeless..


----------



## TLL (Apr 28, 2008)

Steve030687 said:


> I really do want to try another tire, but I am trying to avoid anything larger than 2.1. Mostly for rotating weight issues, but also I don't think I have that much room in between my F100 RLC or rear swingarm.


Granted, the last thing a clyde needs to worry about is rotating weight. 

If increasing tire pressure does not solve the problem, I'd look to a different tire. The F100 will take a 2.3 no problem, so at least increase your tire size up front. I would toss a WeirWolf or Stout on your front and a Prowler MX in the rear. I run a 2.3 stout up front, 2.3 prowler in the rear, and run 28 psi front/35psi rear. I weigh 250# BTW. I have never pinch flatted with this combo.


----------



## bigdudecycling (Aug 16, 2007)

I'm around the same size as you. 5'11" 205. I've been running all my tires around 40psi for a while now, xc tires, am/dh tires. I've only had a handful of flats, let alone pinch flats, mostly cactus flats (arizona) this year,riding all kinds of terrain. So with that said, I would suggest that it is either a hardware problem with your rims, or, as stated a few times, you should go to bigger tires. I ran 2.1 until about 18 months ago when I discovered the wonder that is fatter tires (mostly based on recommendations on mtbr when I asked the question). I recently put a 2.1 on my rear for a race and didn't feelt good on it, I'll probably run only 2.2 and up from now on.....


----------



## k0y0te (Oct 29, 2006)

I'm around 205lb now, and I had the same problem. 40psi in the rear and I got flats all the time.. Anything more than 45psi, and the bike rides like $h*t. Started running stan's tubeless setup about a year ago, and problems solved (almost). 

I'd say, unless you plan on switching to a wider rim and larger tires, tubeless is the way to go.


----------



## Steve030687 (Jan 7, 2007)

The problem is not so much the front tire as the rear. If I am going through a rock garden type area with and speed, I get thrown around and pinch flat. Not like a little pinch flat that eventually runs out, but a catastrophic immediate loss of pressure. I imagine that I change the rear tire 10x more often than the front.

I did a few things that helped me get around this:
1)I stopped using a portable pump and tire pressure checker and got myself a true bike pump 
2) Most importantly, I stopped using cheap-o tubes. I used to get them by the dozens off some bargain basement website, but no longer. This Bontrager tube is holding up very well. Already going on 5 weeks now, where I used to go through one a ride.
3) I got a new set of tires, but I have yet to slap them on the bike because I broke a spoke and need to tension balance my spokes, again on the rear wheel. 

oh, my new tires are Schwalbe Racing Ralph's after they were recommended to me. Not good for rocks, I know, but I am a college student and back in school so my terrain changed. I will go back to the WTB Velociraptors when I got back north.


----------

