Pinch flats

backo
backo Posts: 167
edited September 2014 in Cyclocross
So on only my third outing on my new cx bike I experienced my 2nd pinch. One outing was my first race over grass/mud/tarmac and didnt experience a flat.

The other two outings were local trails, mix of hard pack, mud, gravel etc where I have had the flats.

running x-king 35mm clinchers with butyl inners at around 55psi on each ride. Im new to cx and not 100% sure on things like tyre pressures....I weigh 75kgs. Have found the bike to ride a bit sketchy at times with this much psi in.....my mtb tyres are run on lower psi but obviously wider tyres.

After reading through the internet, It appears the psi should be lower...although I would expect more pinch flats if I went lower?

I know tubs would be the answer but changing tyres round for different terrain routes would be a pain.

Anyone any experience of latex tubes? would these help?

Plan to give the rear rim (the culprit) I good checking over to see if there is anything wrong.

Comments

  • I typically run at around 40 psi on conti cyclocross race (although I did pinch flat on a rocky MTB trail) and about 36 racing on Michelin mud 2s.

    So you sound like you have plenty of air in your tyres. What size inner tubes are you using? Not 18-23 or anything - the bigger the better.

    I weigh about the same as you. This might sound a bit obvious, but if you are used to mountain biking then is it possible you just need to be more careful where you steer and try to avoid big hits on the cross bike?
  • backo
    backo Posts: 167
    thanks for the response

    Think the tubes are continetial tour 28SL 700x 28/37

    I think they do these tubes in 700x 32-47 so as I have to buy some more, I may go for the bigger size.

    Will try the lower pressure this weekend as racing on sunday.

    thanks
  • devhads
    devhads Posts: 236
    Latex tubes would definitely help. I've got them paired with Challenge Grifo and don't suffer from pinch flats. I'm 80kg and go at about 40-45 psi on really rocky/rooty MTB type trails and 25-30psi for racing depending on the conditions.

    I echo what Chris James has said too. I only ever did MTB before cross and you have to remember that you haven't got suspension and try to absorb the big hits in your arms and legs, the kind you would just roll over on your MTB. Better still try and avoid them.
  • backo
    backo Posts: 167
    I must admit I was flying down a section bouncing off all and sundry when I flatted this morning

    Thanks for the advice...will see how I get on with the lower psi this sunday....in last weeks race the bike felt very twitchy especially on wet grass....I almost lost it a few times so hopefully running around the 30psi mark will improve the ride