meangreen

Hi everyone! I want to put the widest tires I can on my CAADX, but I want to make sure there is clearance. I know that the second number in 622-xx is supposed to be the width, do I just measure the space and go smaller? Is using the xx as the tire width a good estimate? Anyone with a caadx put wide tires on it?

Thanks!

StephenH

If you have the owner's manual, that would be the first place to look.

I know you can get different rim widths, so the width of an inflated tire will depend to some extent on the rim- it's not entirely fixed like you might imagine, but I don't know how much it varies, either.

ThermionicScott 

Whip out your 6" machinist's rule (and/or use allen wrenches as feeler gauges) to measure clearance to the fork, brake calipers (if applicable), and rear brake bridge. That'll tell you how much bigger you can go before something rubs.

(Wow, that sounded dirty...)

Jeff Wills

Family list, buddy... just don't get me started talking about wheelbuilding.

meangreen

Great! Thanks! How much room should I leave? Like 3mm per side of tire?

ThermionicScott 

I've got less than 2mm clearance between my rear tire and the brake caliper. Front is more critical, because you don't want something to get caught in there, seize the wheel, and cause you to flip over.

If you have caliper brakes, then you'll want to make sure your tire isn't so big that you have to deflate it to get the wheel in and out. (Or, if you don't mind doing that, knock yourself out. )

- Scott

meangreen

Thanks Scott. when I measured I found that the smallest spacing is on the chainstay (I think that is what it is called). The spacing in the front fork is almost twice as big. Does it ride weird if you have different size tires on the front and the back? Will that help anything? My wrist start to hurt on long rides on the trail. I don't have a MTB bike and can't afford one, so I want to try and make due with what I have. I really appreciate all of the help.

Clem von Jones

Your style of rear dropouts can effectively limit tire size if they are the Campy style that slide forward a bit

pdlamb

It might be worth riding to your friendly LBS to find out. Pick out a few tires you might like, and ask if they'll fit. Try them and find out. Pay the man, and you're done.

If you want to save in the future, you can order the same tire and size elsewhere for when these wear out.

Note carefully: not all tires marked with the same numbers are the same size. Not even from the same manufacturer. They're getting better, mostly, but a Super Sport XL 28 probably is not the same size as a Super Duper Sport ZX 28.

fietsbob

caaduckx? given I don't speak other bike model numbers..
road race style bike probably a 28, Cyclocross style, a 35~37 is a good width.

You want mudguards with that?

I 2nd the Bene Sugg physically go with your bike to the LBS, and shop with them.

meangreen

I actually went in this morning. It turns out there aren't many tires that go much beyond 37 that are 700 and have enough of a tread. The cool dude from my LBS told me that going from 35s to 37s would be a good change.

ThermionicScott 

37s ought to be nice and cushy, but perhaps your wrist pain was from over-inflating the tires. What kind of tire pressures are you using?

This article is not without its critics, but is a pretty good starting point: https://www.adventurecycling.org/reso...SIRX_Heine.pdf

- Scott

meangreen

I usually run about 30-40psi. THe only problem is if the tire pressure goes two low, then I hit feel the rim smash into things. I found some 42s that I am going to try out. The guy at my lbs measured my current tire and it is actually more like 32mm as opposed to the 35 it is labled. He said a 37 would probably be more like a 35 in reality, So hopefully the 42s will give me enough volume for a comfortable ride, with out putting my wheel in danger.

hairytoes

You need more air in your tyres.

For a 32mm tyre, I'd say a minimum of 70psi. 50psi for a 40mm tyre.

It depends on your weight - lower pressures for a lighter rider. If you are over 180lb, add some air to the figures I've given.

meangreen

ok, thanks!

ThermionicScott 

Hmm, 35's with not very much air in them shouldn't be beating up your wrists. At the risk of going off in a tangent, have you had a bike-fitting done?

- Scott