I know... I'm not supposed to...

I've read all over the internet about turning a mountain bike into a roadie, and I've gathered that it's just not going to give you the performance that a roadie does... But what if I was trying to turn it into more like a hybrid/commuter?

Here's the whole story. My Dad just recently got invited to ride with a small team of mostly 50+ year olds just for exercise, slower stuff. Well he's on a mountain bike that didn't really fit into the group. I wonder about the possibility of turning his bike into something that he can still get around on the local gravel dirt streets, but also will perform better, and look better on the road.

He doesn't want an aggressive position, too much strain on the back. And also no gearing changes would be wanted.

I've done a bit of measuring and found out that I could indeed put some larger diameter rims and thinner tires on his bike... Though the one thing that is stumping me is braking systems. I know that if I use a larger rim, the v-brakes on his bike won't be able to contact.

Simple question: Are hybrid frames just made with the v-brake mounts higher on the frame for the bigger rims?

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The power bars and energy drinks... that's the only reason we all ride.

If it were me, I'd leave the rims alone and just go for narrower road tires/tubes. If it's a suspension fork, I would consider getting a lighter rigid fork. You can get by with the MTB gearing as long as you have a large chainring of 44t or so.

I think the biggest improvement is simply changing to 26" slick tyres. At $A100 a set with tubes maybe not all that simple. My favourite commuter has 26 x 1.6" Continental SportContact tyres. These can be pumped to higher pressure than knobby tyres, are puncture resistant and roll well on hard surfaces. They do fine in dirt but obviously lack grip in mud and wet turf.

My other commuter has 26 x 2" IRC Metro Duro tyres. They are slicks similar to above, only fatter, more tolerant of abuse, and expensive.

Then there is my 'dog walkin' MTB with Dunlop tyres that have a smooth centre tread with knobs only on the edges. These will grip on turf when needed but also roll well on hard surfaces.

As you see I like the bullet-proof rigid MTB steel frames and 26" wheels. I have another bike that is an aluminium frame hybrid with 700C wheels and 28mm tyres, and front suspension. This is no faster than my MTB bikes and the tyres can't stand the curb-jumping and potholing that I indulge in.

Front suspension is a small bonus in comfort and a big minus in weight. A sprung seat post or sprung saddle is a better investment for comfort where it matters most!

I agree with the limited consensus (so far) which suggests "road" slicks for the type of riding your father is engaging in ...

If your father's MTB frame has a suspension front fork, then I agree that a solid fork would probably be a better option ...

You are correct in noting that you can fit a larger wheel & tire in the MTB frame ...

You are also correct in observing that a Hybrid FRAME is similar to a MTB Hardtail frame, but you should also note that the BB "drop" on a Hybrid is greater (say, 60mm) than on a MTB Hardtail (closer to zero) because of the 700c wheels/tires on most Hybrids.

A few years ago, I performed an extreme makeover on an "extra" Hardtail frame that I had (see attachement) -- the fork is a ROAD fork & the wheels are 700c. Except for the top pull front derailleur, all the other components are road components.

The rear seat stay bridge was 'close' enough that I was able to use the a Tektro "long reach" brake caliper -- I had to enlarge the forward side of the hole in the bridge to allow it to accept the brake's recessed nut. There are brake calipers which have a LONGER reach than the particular brakes I used & you need to measure the actual distance for the particular frame & wheel combination.

Because I used a road fork, I used a road brake caliper on the front, too -- the reach on the particular Tektro caliper was suitable for the front fork, too, so I didn't have to mix-and-match calipers.

Installing a road fork changed the frame's geometry -- the BB drop (without actually measuring it) is now probably about 40mm & the head tube angle is now probably about 73º/("standard" road geometry). The combined changes to the geometry were "a good thing" for the intended riding (i.e., on the road ... mountain roads).

N.B. Because the particular Hardtail frame is alloy, I had to lace the 700c rim on a 135mm rear hub ... another Hardtail frame which I am in the process of converting is steel, and I respaced the frame to 130mm so I can use any of my regular road/(130mm) wheels in it.

The spacing on Shimano hubs can be changed by simply replacing the axle & adding/removing spacers.

As far as I know, most Hybrid rear wheels have 135mm spacing.

Please note, IMO, a person should NOT choose a Hybrid with a suspension fork because the larger tires should provide the necessary cushioning which most people may want to have ...

If a person wants a front suspension fork for 700c wheels, then s/he should buy a 29er (at least, a 29er fork).

IMO, a reputable bike shop would not sell a Hybrid which has a suspension fork because it is an unnecessary added cost + unnecessary additional weight AND probably the reason that akdadat finds his Hybrid to be no faster than his Hardtail(s) -- the exception would be "chain" bike shops (e.g., Performance) which may have to stock "stuff" that some corporate bean counter selects for the shops.

That's 'my' opinion regarding suspension forks on Hybrids ... for whatever it may be worth.

BTW. Even though you indicated that you don't want to change the gearing, an unplanned future change may be to replace the MTB crankset with a ROAD crankset because your father will probably find that he can pedal much more aggressively after you change the tires & the gearing may eventually be too low to suit the riding conditions.

A 48t chainring is the largest commonly available (i.e., you can translate that as "affordable") chainring size for a 104BCD 4-arm crankset. That may be a large enough (future) change.

So, when that day comes, you need to know that a ROAD "double" will often NOT fit unless you choose a BB spindle intended for a "triple" because the crank arms & chainrings need the additional width to clear the chainstays. You cannot, therefore, install a Shimano Hollowtech II or FSA MegaExo or Campagnolo Ultra Torque "double" (especially, "compact") crankset on a MTB frame.

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We have Bontrager Comfort B tires, which have a similar tread pattern to your Dunlop's, on my wife's Trek Navigator MTB. The smooth center tread has a bit of a raised peak and when inflated to the max of 65 lbs, they really roll well.

That bike is a little faster on a steep downhill run than my road bikes. Of course, it weighs twice as much...

It looks like Mavic make what you need for this....

www.Mavic.com - Products - Caliper Brake Adjuster

i used metro 1.5's on my crossrides and i got them for around $15.00 a piece, new. and i agree with what was already said, bigger front ring.

So, from all the input so far... I am thinking about using some road brakes, and some tougher 700c rims on the bike, I don't know if a new front ring is in my budget... but maybe that'll be an addition later.

The reasoning for this decision is that two of my v-brakes just gave out on one of our mountain bikes... so I need to get two brake calipers anyway. Thus the two road calipers.

And the rims... My brother's road bike has some fairly heavy, yet heavy-duty rims, which he doesn't need heavy-duty at all, they are probably just slowing him down. So I am thinking about getting him some nicer road rims and giving those heavier ones to my Dad. Since hes going to be doing a bit of rough-road riding also, he'll need the strength in the rims.

And as for tires, I'll probably get him some nice narrow tires, but with tread on the sides where it counts.

And I hope you all know he's not looking for a great performance enhancement, he doesn't want to be going faster, mostly just easier on roads.

Sooo, any objections, comments, criticisms... Speak up! I'd like to know before I make a mistake.

And thanks again to everyone for the help.

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The power bars and energy drinks... that's the only reason we all ride.

I have converted a hardtail Rocky Mountain "Blizzard" MTB to an ersatz road bike in the past, illustrated here.

Still, at some point, such projects are a losing proposition, from an economic point-of-view. Better to just switch to road tyres, rather than replacing wheels and brakes.

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