Hi guys
When the terrain is slick ,flat turn and some rocky enought to pinch
your tire.How many Psi of air pressure do you guys usually put in the front and rear on 18 inch and 19 inch rear to survive the cross country style raced and maximum tracktion for the whole race (if you not bad luck).I air my front 14 psi,rear 10-12 psi on my 18 inchs rear,I put 15-16 psi for my 19 inches rear tire.I don't seem to have a good traction but I hate flat tire.Some pro told me he put his 18 psi front n rear on 19 inches on the time,I think it's too much.
Tony
I have been told most of the top GNCC riders use the foam inserts instead of tubes so they don't have to worry about flats at all. The Michelin Bib Moussee inserts are suppose to be the same as 13psi. And can be used with MS2, StarCross MH2, S12, M12, H12, Enduro Comp III, and EnduroStar. If I raced cross country or enduro I think I would try them.
I ride in soft sand conditions, but with alot of roots across the trail. I use 8 - 10 psi front and back. Anything more and my Michelin M12's feel like skates on ice, and the ride feels very harsh. I've heard people say the the M12's have a relatively stiff sidewall, so I think that really plays a big factor. With softer sidewalls, you would need more pressure etc... Obviously, different terrains call for different pressures also. Just experiment, and see what works for YOU and where YOU RIDE. Good luck.
I'm with snaggle on this one. Tire type and terrian would play the biggest factor. I run 10 to 13. If its wet I run 10 and if it's dry I run 13. I have a dunlop 739 in the front and a 756 in the rear. I like the combo very well. The trails I ride most of the time have many types of terrian on the same trail. Mostly, its either sandy or hard pack, but it has all kinds and can change in a hurry on you. It realy sucks if its too wet, but after it dries out just a little or you get just the right amount of rain the hook up is awsome. I also run a tire sealent. Plenty of catus and mesquite brush to poke holes in you tires.
Thank you for your time everbody
As I read, look like 13 psi is good all around for everybody.I think tire type are importance ,but we are don't have much money to change diffrerent tire from race to race ,so usaully we use dunlop D 752 rear.Any body can tell me more about Michellin S-12 ?
Thanks
Tony
The 756 is a little better tire than the 752 for all around use IMO. It handles the soft stuff very well and crosses over to hard pack well too. I run 12lbs in my tires front and rear regardless of terrain, works well for me:)
TonyKX
This is what happened last weekend to my friend at the Wilseyville hare scramble in CA. The course was perfect traction, but very rough in spots, with tons of sharp rocks and slick roots. Just before the race, my friend lowered his front tire to 12psi. He was running a Michelin m-12 (notorious for pinch flats because of their THIN sidewall.) Michelin makes an enduro tire with the same tread pattern as the m-12 with much stiffer sidewalls. Anyway, he flatted on the second lap in a rocky creekbed ruining his day.
I ran 14 psi in my front (12or13 normally) because of the rocks. I had no problems or any new rim dings for that matter. Better safe than sorry in a race. We both run heavy duty tubes btw.