# another bike fitting question: 19" vs 21"



## aaalllen (Aug 18, 2010)

So I'm trying to decide on a 29er frame size for me. The wrench science site suggested a 19" frame (see below). At rei, the ponderosa 29er in XL w/ a 20.5" frame... it felt pretty good, but that was on flat ground.

I would use the bike to commute to work and back w/ some gnarly SF hills in the way and long/fast/windy paved downhill on wet dewy/foggy roads (radar detector has clocked bikes going more than 35). And will try to get to off road some single track on weekends.

What will be the pros & cons between 19/21? I'll probably visit some local shops this weekend to try out more bikes, but this fit thing is going to drive me crazy all week. Any advice/suggestions/comments would be greatly appreciated =)



wrench science

Your Measurements 
Height: 75.00 in
Sternum Notch: 62.25 in
Inseam Length: 35.00 in
Arm Length: 27.50 in
Shoulder Width: 22.00 in
Flexiblity: 9
Weight: 230.00 lbs
Foot Size: 13.00 USMens

WS Recommended Sizes 
Frame Size center-to-center: 19 in
Frame Size center-to-top: 20 in
Overall Reach: 73.54 cm
Saddle Height: 78.50 cm
Handlebar Width: 46 cm
​


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## Ray Lee (Aug 17, 2007)

I have no idea why bikes are sized my the seat tube.... my 19 inch is larger/longer than my 21

I feel like the top tube is a more important number but even that can be skewed by head and seat tube angles... the best measure is actually the reach but most dont tell you.

best to try them out, personally I would rather error on the side of a little bit to long than to short... 60mm stems I can get used to... long stems tend to toss me over the bars when things get steep and tech



aaalllen said:


> So I'm trying to decide on a 29er frame size for me. The wrench science site suggested a 19" frame (see below). At rei, the ponderosa 29er in XL w/ a 20.5" frame... it felt pretty good, but that was on flat ground.
> 
> I would use the bike to commute to work and back w/ some gnarly SF hills in the way and long/fast/windy paved downhill on wet dewy/foggy roads (radar detector has clocked bikes going more than 35). And will try to get to off road some single track on weekends.
> 
> ...


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## AndrwSwitch (Nov 8, 2007)

Have you been riding regularly, or is this your first bike after a bit of a layoff?

People often buy too small a frame when they're just starting or getting back into it because larger frames become comfortable when the rider is exerting torque on the pedals, and how much torque someone exerts (and how much it lifts them) depends a lot on strength/weight ratio. On the other hand, if a frame is too big, you may never be able to make it comfortable.

If you can from where you're test-riding, try sprinting, riding up some hills, riding down stair sets, hopping curbs, wheelies, etc. Too big a bike will be problematic to wheelie and hard to ride down stairs; too small a bike will feel cramped in an out-of-the-saddle sprint or a climb.

Are you going to the REI in SoMA? Hard to find any climbs without getting pretty far away. There are a lot of great shops on Stanyan St. that are close to the park and hills and carry some other brands. I don't think there's anything wrong with REI's brand, necessarily, but each brand fits a little differently and it's worth putting some time into finding "your" brand.


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## aaalllen (Aug 18, 2010)

If the measurements don't help, let's say i'm 6-3, line backer shaped with long arms and legs. I have a 97 18" kona cinder cone from college. I've grown 4+ inches since I've gotten it and compensated w a a stem raiser and have the seat post all the way jacked up for. It definitely feels short and feels better w/ my hands on the longer style bar ends during a ride. 

The last few years it's had hybrid tires for pavement rides. Nothing strenuous or regular though. Since you know SF, my longer rides have been from Laurel Heights to Tiburon and back w/ much pain on some of the hills or the iron horse trail from Walnut Creek to Danville.

I'd like to get into trail riding. One of my other goals will be to commute to the Presidio Main Post either through Arguello or Tennessee Hollow. I quit Arguello because on a wet/dewy morning, my rear tire sketched out on one of the bottom curves and I was lucky not to fall. Getting to Tennessee Hollow has some parts labeled > 18 degrees on the SF bike map.

Yeah, the SOMA Rei and San Carlos ones are on flat ground. I was thinking about visiting the 2/3 near Stanyan/Frederick, Mikes Bikes, Valencia Cyclery and/or the one at 8th/Irving ish. Other suggestions?


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## AndrwSwitch (Nov 8, 2007)

I got my LeMond from a shop now called Roaring Mouse. I think one of the guys who worked there when it was Open Road is still there; in any case, when I've been back since it's been good.

http://www.roaringmousecycles.com/

My Mom got her bike at Nomad Cyclery. They seem alright, but I've only been there once myself.

http://www.nomadcyclery.com/

I think there's a lot to be said for having your shop be within walking distance, if there's a good one that close.


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## Koppuh Klyde (Jul 13, 2010)

I was in your shoes about a month ago. I accidentally" bought a 19" Fuji 29er thinking it was the large. Thats what the guy at Performance told me (on the phone) so I bought it. After doing more research I found out it was the medium. I was gonna cancel but I decided to at least sit on it. Well, Im 6'4" and it seems to fit pretty good. Id probably "fit" the 21" better but Im just happy about saving $300 on the bike. Im in Cali too but in the foothills. Out of 4 LBS only one had a 29er in stock. It was a Spec. HR 23" It was definately too tall. Well good luck and let us know what happens.


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## CasualFan (Aug 4, 2010)

At 6'3" with a 35" inseam, I think a 21" frame should be perfect for you. I'm 6'2" with a 33" inseam (short legs for my height). I test rode the XL Novara Ponderosa 29er you're talking about at REI and there wasn't quite enough room downstairs for the boys for me. With 2" longer legs, I would think the XL should be perfect for you. That bikes looks really nice and comes with very good components for the price. It's probably a little on the heavy side, but that might not be a big deal. I can't believe they are marking it down from $900 to $650. I probably would have bought one if they had a size in between. Seemed like the XL was slightly too big but the L was too small and I would have had to pull the seat way up high. I'm going to order a 2011 Kona Kahuna on Monday. The 20" should fit me perfectly (I hope). Good luck...


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## the old fool (Jan 27, 2008)

I'm 6'3" and I can ride a 19" ok but a 21" is a better fit ... trouble is it seems to vary between brands and i have had one place try to sell me what they had not the correct size.
Try the same model of the same brand in different sizes and see what you think


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## RacerLex (Jan 20, 2010)

At your size I would definitely get a 21". I'm 6' and ride a 19" comfortably.


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## aaalllen (Aug 18, 2010)

Most of the LBS I've visited only have 19" frames and push those hard. I'll keep looking. Thanks for the advice folks.


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## distrktFIVE (Aug 17, 2010)

I am 6' and I am very new to all this but I just bought a 21" Spec Hardrock Sport Disc 29er. I rode a 19" as well but just liked how I felt on the 21". I only have about 2-3 inches of "groin clearance" over the top tube though...


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