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The best way to buy a bike is to go into a shop, explain what you’re looking for, and then choose the most appropriate model. Then, working with the shop, get properly fit to the bike. That’s the recommendation I give to people who come into my shop looking for a type of bike I don’t sell.

But how does this whole thing work when I’m here in little Point Reyes Station and you’re out there in Rapid City, SD? Chances are you’ve already got a bike (or two, or three, or … the whole n+1 thing) that you feel comfortable riding. I work with you to get some measurements off your bike and create a drawing of my frame with your contact points so we can verify the proper size for you.

I also like to confirm that your seat height is properly set. I’ve found the proper method for setting a proper seat height, barring an actually hands-on fitting to a bike, is to get your actual inseam measurement and multiply this by .883 – also known as the LeMond formula. But what is your actual inseam? It’s not your pants inseam. It’s the measurement from the ground up to your pubic bone. To properly measure, you’ll need an assistant and a book that is about as wide as the nose of a bike seat. Stand against a wall with your sock clad feet about as wide as your pedal stance and pull the book up against your pubic bone. Pull up hard as if your body weight is pushing down on a bike seat. Make sure the book is square against the wall so you get an accurate measurement and measure from the top of the book to the floor. It helps to repeat this procedure a few times to make sure you’re getting an accurate number. Then take this number and multiply by .883 – this is your seat height. This seat height can vary a small bit based on riding shoe thickness, pedal style, and knee flexibility.

With this number confirmed, I’ll use three other measurements from your bike to create a drawing showing how you would fit on one of my frames: Seat set-back, handlebar reach, handlebar drop. At this time, we will also talk about how you might want the fit of this new bike to fit differently than your current bike.

I’ve done this for countless current owners and will continue as it is the most accurate method to ensure the proper size via long-distance.

Two methods to measure the seat setback are:

• Drop a plumb off the nose of the seat and measure the distance to the center of the bottom bracket.
• Push your bike against a wall.  Measure the distance from the nose of the saddle to the wall, horizontally, measure the distance from the center of the bottom bracket, and then calculate the difference.

If you want to figure out your size on your own, here is a suggested seat height range based on past fittings to frame sizes.  If your seat height falls within the specified ranges, you should have adequate standover clearance.

Suggested sizing recommendations for La Cabra
The minimum and maximum sizing recommendations for La Cabra are based roughly on using a dropper post with between 100mm and 125mm of travel. Dropper posts of that travel range have an approximate minimum and maximum exposed seat post of 160mm – 260mm. There are many other factors that may limit seat height. Make sure you measure carefully per the manufacturer’s sizing guide if you are planning to use any dropper post. Black Mountain Cycles is not responsible for errors in sizing based on the use of a dropper post.  If you are comparing sizes between the La Cabra and my other sizes and see that the top tube lengths on the La Cabra seem long, know that I did design the La Cabra frame with a longer top tube than the Mod Zero frames so there is more foot clearance and to run a shorter stem than you would on other frames.  Use this page in coordination with the geometry page and look at the stack/reach numbers too.  For reference, I run a 120mm stem on my Mod Zero, but I run a 100mm stem on the La Cabra frame.

Suggested sizing recommendations for the Mod Zero frames.

Frame Size	Minimum Seat Height	Maximum Seat Height	Rider Height Range
44cm	63cm	69cm	5’0” – 5’5”
47cm	67cm	73cm	5’4” – 5’8”
50cm	72cm	77cm	5’7” – 5’11”
53cm	75cm	80cm	5’10” – 6’1”
56cm	78cm	83cm	6’0” – 6’3”
59cm	81cm	87cm	6’2” +

Suggested sizing recommendations for the rim brake Monstercross V6 frames.

Suggested sizing recommendations for the rim brake Monstercross V5 frames.

Frame Size	Minimum Seat Height	Maximum Seat Height	Rider Height Range
52cm	68cm	75cm	5’3” – 5’6”
54cm	70cm	77cm	5’5” – 5’9”
56cm	72cm	79cm	5’8” – 5’11”
58cm	74cm	81cm	5’10” – 6’1”
60cm*	76cm	83cm	6’0” – 6’3”
62cm*	78cm	85cm	6’1” – 6’4”
64cm*	80cm	87cm	6’3” +

*Only 60cm, 62cm, 64cm V5 frames are available as of Jan., 2024