something strange...
 

while pulling up to my apartment building last week, I noticed an unusual bike chained up on the street. The bike itself looked like a mountain bike setup. Was one of those frames with a big spring built into the frame and all...anyways, what made this particular bike different is that it was mounted on a road/touring wheelset.

It was not just a pair of slicks on MTB rims, but an entire rim/wheel setup -- after my astonishment wore off, I thought it looked kinda cool and I want to see if it works on my old, beatup RockHopper. I have some old Schwinn Road rims/tire set with a 7-spd cassette and want to give it a shot -- What d u all think, is this safe?

Make sure the wheels are the same size, and that the hub spacing is the same and I dont see any problems.

Maqke sure the brakes reach the rims properly.

also, a 9spd chain may not work with the 7spd cassette

It sounds like you're talking about a 29er. That's a mountain bike built for 700c rims. You may be able to fit 700c wheels on your mountain bike, but you may not have functioning brakes because they won't reach the rims. No, that wouldn't be safe.

The chain will be fine. Cog spacing may/will cause trouble.

cool....if not my RockHopper, what other decent, used "29-ers" are out there that would work for this conversion? Thanks

http://www.surlybikes.com/frames/ima...te_detail3.jpg

Karate Monkey

http://www.surlybikes.com/karatemonkey.html

Unless you build up the wheels with 700c rims and mtb disc hubs!

29" mountain bikes have become fairly popular, there used to be a few smaller brands that made frames for them, now with the Gary Fisher brand leading the way, they're out there in larger numbers these days. To be considered a "29er", the wheel/tire combo is a 700c rim with at least a 2.0" wide tire. Stand one of these next to a standard 26" wheel/tire and you'll see that there's a striking difference. Obviously there's approximately three inches difference in diameter, but there are a couple of measurements that are more important: the approx. 1.5" difference in radius, which means you'll need approx. 1.5" of clearance beyond a traditional 26" tire under the fork and at the chainstay and seatstay bridges. The other thing is the brakes; if you're currently running rim brakes (on an older Rockhopper it's likely you're either running cantilevers or v-brakes), there's no way the brakes are going to align with 700c rims. Another poster mentioned disc brakes; even if your "old beat up Rockhopper" is disc compatible, along with the fork, you're getting into the realm of some big bucks to make the conversion (assuming also that your frame/fork has all the clearance necessary for a 29" wheel, which is doubtful). If you really want to go with a 29er (it really is an advantage in some ways), my advice is to forget about converting a bike made for 26" wheels and go with a frame and fork that is meant for 29" wheels-

edit: after re-reading your post, maybe you're just talking about putting 700c or 27" rims with road tires on them on a standard mountain bike. That's more do-able, but the brakes would still be a problem-

a really nice cheaper option for a 29er is the one made by SE... i cant offhand remember the model name but its an aluminum frame rigid mtb designed for disc (and cantilever i think) brakes and for 29er duty... comes built as a single speed with a chain tensioner (micro-drops mean no fixed gear though)... but it has a derailuer hanger and cable stops to go multi speed...

mmm looking at www.sebikes.com they have a rear entry one too called the stout so im guessing that they may have changed the design... but it does still have a removable derailuer hanger

anyway... aside from that surly, gary fisher, kona, and countless others make a 29er rig... i just know i could have gotten a scratch and dent SE for like $200 retail was like 4 or 500
-pete

Since 29" mountain bikes have just recently gained in popularity, you may have a hard time finding much on the used market. If it's just that you want a bike with larger than 26" road tires along with an upright riding position like on a mountain bike, I'd suggest a used hybrid bike. They usually are equipped with 700c rims and put the rider in an upright position with mountain-style handlebars. But since it seems you described the bike you saw as having full suspension, you may be out of luck on that unless you want to spend some fairly big bucks...........In regard to my above lengthy :D post, I apologize for not reading your original question more carefully, and then not reading through the thread and seeing your follow-up question. At least you got a little background info on 29ers. And in regard to a 29er mountain bike with big 29" knobbies, the main advantage is fairly simple: relative to the larger wheels and tires, obstacles are smaller. :)

it actualy seemed like the 29er he saw had 700c tires on it... at least thats what i got from his first post... which would be cool and make sence on a bike primarily used on the street....

-pete

Maybe it was just a standard mountain bike, and the owner had managed to put larger diameter rims, probably 700c, along with road tires on it. And managed to work around the brake issue somehow. I don't know. I think I just wanted to talk about 29ers- :D

I find it amusing. I bought a Fisher Dual Sport 229 in 2004. Everything was labled as 700xXXmm. When I went to buy a new tube this year, they are all listed as 29xX.XX".

it seems like way too much drama to try to fit a 26 mtb frame with 700c rims and try to make brakes work and all that crap... but on a 29er... it would just be a matter of changing rubbers... i'm willing to be it was a 29er with a smart owner who knew that knobbies suck on streets and his mtb has road bike wheels on it... haha

and yeah... talking about 29ers is fun... and now i want to buy the new se 29er... the only thing they kept me from buying the scratch and dent was the micro drops... the change to rear entry makes me all hot and bothered
-pete

I recently did a century, and my riding partner was riding an '04 Fisher X-Caliber 29er, with road slicks on it. They're very versatile bikes..........I'll take one in custom-built steel, fully rigid, vertical dropouts, and disc brakes, thank you very much- :p

I love the 29, and I love the single speed. Somewhere on the want list is a SS 29er, but I don't want anything to do with rear entry dropouts. Sliding drops or an EBB with disc brakes is where it's at. I've got track ends on my fixed gear and they don't add anything but making changing a tire a little more of a pain.

Fisher has a model called the "Ferrous" that's a steel, geared 29er with an EBB and vertical dropouts. It may be brand new for '07, I'm not sure. Cool looking bike. But for me, absolutely no desire for singlespeeding, so I'd rather stick with the "simplicity" of vertical drops and a conventional bb-

Here's a link to the Fisher Ferrous 29: http://www.fisherbikes.com/bikes/bik...bike=Ferrous29

ebb's worry me... they would be just fine for ss but i wouldnt run fix on it... and since i originaly wanted a 29er as a snow bike, and wound up with a beautiful kona kaboom 26in rear entry fixie for snow duty... im still very excited about the rear entries... but to each thier own in this wonderful world of bicycle versatility... for an offroader i would want a freewheel on my less-sadistic days... hurray for flip-flop hubs!
-pete

I have no interest in fixed on the dirt. AC Racing, ACS Claws F/W or a SS Casette hub. No Flip Flop either because I want discs.

well the flip flop is on my snow bike... hydraulic fron disc... and no rear brake
since its primarily going to be in fixed mode... i might add v-pulls on the back for summer again... but havent decided yet
-pete