CanadianBiker32

Ok suggestion of a tired pressure. This will be for riding a fat bike on a groomed XC ski trail for a winter time race

the event is the Fat Bike Birkie later in March 2015
37km on a groomed XC ski trail. Suggestion, would i run very low pressure or go higher? like a 10psi or anything? thanks

revcp 

For me, a "tired pressure" is any oft repeated expectation by someone else that is solely about that person's need to be in charge, to be paid attention to, etc.

modernjess

What PSI do you normally ride, where, and what conditions? How heavy are you? What's tire/rim combination are you running? What is the weather going to be that day? Will the snow be frozen or slushy or deep or packed or gone?

In short I have no idea what to tell you, but if it were me (big guy on a Moonlander with 4.8' knobbies on 100mm rims) on packed snow, I'd start at 10 rear 9 front. It's possible that I'd want to stop and let some out depending on the conditions and how the bike is handling, which is a quick remedy, but it's pretty doubtful that I'd want to pump them up any more that. I've learned with practice and experience what works for me, of course YMMV

Good luck!

FBinNY 

There's no magic answer here. Roll a pair of dice and come up with a best guess pressure and go ride. Then adjust based on the results. More pressure rolls more easily, but will tend to cut into the snow when you come off bumps, or hit variations in the surface. Lower pressure floats better, but can be harder to push.

In your shoes, I start at the high end of what I thought made sense, then bleed air if they don't float well. You could also carry a pump so you could go up also, but these larger tires can take a long time to pump.

bicyclelove

Hey I'm doing the same race this year. I just got my fat bike after drooling over them for years. My plan is to ride a lot between now and the race to figure out tire pressures that work. So far just riding on trails I've found around 10 works well. I'm a Clyde at 220#. I will fine tune my pressure hopefully with more saddle time. So far I'm having a blast with this bike. So much more capable than a studded MTB.

CanadianBiker32

Hello all quite experienced on fat bike now, having done the Frozen 40 as well this year. doing the Fat Bike Birkie this weekend which is going to be a groomed trail, . up here been usually riding at 5psi as we have lots of snow, and deep and soft.
for Birkie- conditions warm = like -2C or event +1C . i weigh 169 lbs.
I am thinking keep tires hard on that course? as be almost like riding on a road? or higher PSI.
suggestions are most welcome, and don't worry i won't be beating Ned Overand or even close to that. just average placings
but all advice for tire pressure suggestions be great. thanks

chriskmurray

I personally would suggest starting out at 7psi for 4" tires and 6psi for 5" and adjust from there. Rider preference and snow conditions can make the ideal pressure change significantly. Even with groomed snow, not all groomed snow is the same.