My brother-in-law is getting me into biking, specifically mountain biking. I don’t currently own a dedicated mountain bike yet which would be ideal, so I am left using a bike more suited for gravel and paved roads if I had to assume. The tires on it are Panaracer Comet Hardpack 700x38c tires. My two questions are:
1. Are these tires sufficient for your standard trails (no drops, just roots, rocks, etc)?
2. If yes, what psi should they be at to get the best experience possible? I understand that psi depends somewhat on the person’s preferences, but I’d like a reference point if possible. I also weigh around 220lbs if it matters.
Thank you for the help! I have much learn about all of this, but I am trying.
Maybe OK for gravel roads and very easy trails. Maxxis Rambler 700/40 would be a bit better. That is the only tire I could find with a decent off road tread that will fit on my wife’s hybrid bike, it has a narrow frame triangle. They work pretty well, but she rides only beginner trails. We also have replaced her front tire with a 2.10in Rocket Ron. Wider front makes a huge difference. You can generally get by with a thinner tire on the back, but you want something with good traction on the front. If you have a skinny tire on the front you will have to run higher pressure so it can dig in too much cornering, and be more slippery on rocks and roots.
I would start the 38×700 or 40×700 tires at 35lbs and lower then a bit at a time until it feels best to you, or you feel your rims hit over roots or rocks or you get a pinch flat, then go back up 2 or 3 psi. If you run the 2.10×29 on the front I would start that with 25psi.
And just in you didn’t know 700mm rims and 29in rims are the same diameter. 700s are usually narrower for street tires, and 29s are usually wider for dirt tires. But a 2.10 tire will usually fit fine on a bike that came with 38×700 tires if it will clear the fork or frame.
700c and 29 are the same size rims. For serious Mountain biking, you’re going to want 29×2.2-2.6in tires and pressures in the 35-20psi range (given your weight). As the tires get wider, the pressure gets lower. For Gravel biking, you’re going to want 700×38-50mm tires and pressures in the 50-30psi range given your weight. I would take your bike to your local bike shop and see what the widest tires your bike can fit—which will depend on frame and fork clearance and rim width. I prefer wider tires because they are more comfortable and provide more traction on dirt. However, narrower tires will roll faster on pavement. For mountain biking, I would put the widest tire that will fit on your bike. Also choose a tire with an aggressive tread pattern.