Just received a pair of Conti GP4000 tires from ProBikeKit This is my second set of these tires. The problem I've encountered is this: The rear tire won't go on. The first tire I put on the front was pretty snug, but I managed to get it on. I have had riding friends try to get the second on one and this tire is just too small. If I ever flatted, and of course I will, it would be impossible to get this tire off or back on. It's maked as a 700x23c but it even takes a tire iron to get the one side of the bead off to get the tire off the rim. Anyone else have this issue with the GP4000? :mad2:

I had the same problem with putting my new 4000 on a zipp404 rim, it was really snug but it went on, I had a flat tire only 100kms after putting on the tires. I was scared that it would be a pain taking off the tire for the tube change, but to my surprise it was pretty easy, I guess the tire stretched. So you might just have to work at it to get it on the rim...good luck!!!

yea the bead will stretch as it sits on the rim


take off your rim tape, and make sure the portion of the tire that is on the rim is as far into the rim as possible...this will give u the most possible space to get the rest of the bead on.

may even have to do one at a time...even a 12 or 24 hour stretch one bead at a time will make a big difference.

Thanks for the feedback. But I have never seen a tire this tight. A friend of mine who has been riding for 20 some years gave it a try and even he admitted defeat on this one. It really appears to have been made too small. I don't know how that could be though. This is my second pair of this particular tire. The first set were a little snug the 1st. time mounting them, but nothing like this. My fear is that even if I got it mounted, trying to fix a flat could prove near impossible unless it did some serious stretching while on the rim.

I have used GP4000 tires that I got from Probikekit in May without any problems. I mounted a new tire without tools onto a Crostini rim on Sunday. It's either your rim or the tire.

Tire. It's going back. Just mounted another conti on it without even using an iron. Go figure. How does a tire end up too small?

mines gp4000s go on and off with no problems. you might have a defective set.

I've used Conti's for several years & normally they run about 2mm diameter less than what is on the side wall: i.e. 23 mm is most likely 21 mm. That latter makes them somewhat harder to mount, but it sounds like you have one that is even smaller than the normal 2mm.

Humans make them.