Has anyone tried running a 650 rear/700 front wheel combination? I’m going to build another set of wheels for a fixed-gear and thought this might be an cool way to give the bike a little more personality and possibly my increase cadence at the same time. Any thoughts?

if you wanna increase your cadence just move to a smaller chainring or a larger cog.

the smaller wheel will look rather goofy in a 700c/27" frame. that's just my opinion though. i cant imagine it'd be very comfortable either, you'd have to tilt your saddle nose-down quite a bit.

It will screw up handling of bike a fair amount.....make the steering a little slower.It would be ridable though.More importantly it will make the BB that much closer to road,and that isnt good on a fixie.

I thought Marco Pantani rode a custom built in the 98 tour that had a 650C front and a 700C rear to get him aerodynamic for TTs cause he was such a small fulla

Brendon

I thought this would be a cool way to give the bike a little more rake without changing forks and add the sloping top tube look. I didn’t think there’d be that much difference in bottom bracket to ground clearance to matter but I guess so. The ‘80s Cannondale MTB bikes used a 24r/26f wheel combo that was really trick looking in its day.

Thanks for the comments.

Did you have in mind the opposite of this?

lots of MTB's/dirt bmx bikes to that because the smaller back wheel will dig in for straight traction, and the fatter front wheel helps steering a lot.

*ps- that keith harring bike is nuts. i'll take 2 please*

that's my purstuit. i LOVE the way it handles. and when i say LOVE, i mean i would have sex with this bike if there was a suitable orifice.

you can't tell from the pic, but the top tube DOES slope, and the front wheel IS smaller than the rear...also it's about a 50cm seat tube, so the slope isn't all THAT dramatic...definitely not as dramatic as that other bike...i should really get taller frames...

oh wait...yeah, the topic...umm...650 rear/700 front would be bad. very bad, yes, unless the frame was built for it...maybe some nice builder would put it together for you on the cheap...then again, probably not. it also wouldn't be legal to ride on the track, but you probably don't care about that...even 650c fronts aren't legal anymore...stupid UCI...

suitable orifice? WHAAAA????
Doesn't that have a "BIcycle Topic" unto itself? Very Cycle-philic...

i don't see the topic that talks about bike lovin'.

i was just saying...that riding that bike is better than sex.

a few nights ago i went for a 3-speed cruise around the city with a friend. i borrowed my GF's dumpstered 3-speed, and we cruised for a bit. then i decided to come home and switch bikes. cause that bike is TWEAKED. so i hopped on that yellow monster and i said to my female companion as we rode down a darkened street "wow! this bike is like...i can't describe it...it's like..."

"yeah, it's really excellent," she said (i let her take a few laps in a parking lot earlier).

"IT'S LIKE SEX!!" i exclaimed.

she said: "uhm...yeah...i guess it is, it's really nice."

then i giggled and i think i weirded her out.

I was thinking about doing the same thing...
I figured it wouldn't be good for my front though.

Bar spin away!

But these bikes were designed with consideration to the wheel sizes.

bump de bump, yeah....but how does this combo on a road bike (if meant for climbing, thus, necessarily, descending!) not help? i realize geometry is affected a bit (how much?), but i would think that if the 69er idea works for some bikes, why not the 700-650er? adust the saddle, the bars a bit....

has anyone done this for road? not all that curious about fixie/cool looks. this is about performance.

Dude.. you made a bad choice.

Do you see anyone using that wheel setup in a professional racing setting? No. Not on a MTB not on a road bike. This should tell you something. If the R&D departments at bike manufacturers around the world see no use in it then it obviously isnt going to help your performance.

Imma try 650cc rear and 700cc front. yep.

actually, being a mtbiker who is starting to road (and not pro racing...), that's why i asked...because the seemingly similar larger front wheel set up of the TREK 69er WAS raced by folks and if you check out reviews, yes, some thought it was great for racing. https://www.mtbr.com/cat/bikes/29er/t...7_1548crx.aspx

still, not worth the experiment since i don't have a rear 650 wheel.

There are advantages to a 69er off-road, mostly that it allows you to spin up the lighter rear wheel and still have rock clearence with the front wheel. And that is for bikes and forks designed to use such a setup.

There are no advantages to this setup on the road, especially when the bike is not designed around the smaller rear wheel.

The only way it would be even remotely sensible is if you were using a very fat tire (50mm+) on a bike that could not otherwise use fat tires, and you didn't need a rear brake.

I knew a guy once that rode a bike similar to what you are talking about. He had a Schwinn Cruiser with a 20" wheel on the back and a 26" wheel on the front. I don't see him anymore. He left town with the rest of the circus.