Cyclocross - Is a 54cm Kona Jake too big for a 5'8" person?

I went to the Dave Moulton site, and according to my body size, inseam, foot size, etc., I came up with 54cm as being my correct frame size. I have read where Kona Jakes run large, so I'm wondering if the 54cm is correct. Anyone have experience with these bikes?
I have a line on a used one.

I'm 5'8" on a good day. My road bike is a 55. The bar is "personal" but no problem. A 54 sounds about right to me but I am unfamilar with the Kona. FWIW.

It depends on how long your torso is and and what the top tube length is... I'm 5'8" with a 32" pubic bone height and the 55cm top tube on my Giant TCX was too long (would have been a 54cm seat tube). You really need to size by top tube length (effective, not actual on compact frames) instead of seat tube... BUT, a 54cm seat tube bike is generally considered standard for someone 5'8"...

BTW- A tip on a used bike...ask if the steerer tube has been cut on the fork. This my make the difference between a really "Aero" position (read uncomfortable for most) or a more relaxed, upright position.

My buddy has 2 Konas that are 54's and he has a 30" inseam.

At 5'8" 54 cm is too big for me. I ride nothing larger than 53cm with a maximum toptube of 535mm. I like my bikes short enough to be able to ride in the drops for an indefinate amount of time. I believe people buy or are sold bikes that are too big for them then wonder why they feel pain in their hands, wrists, back etc after extended rides. I'm certified to bike fit and would personally rather fit you to a bike smaller than 54. With modern compact geometry and sloping toptubes inseam measurement is useless. I can stand over a 58cm bike and still have clearance but the bike would obviously be too large for me.

The best way is to test ride one. However, you may want to go a size down.
The TT is about 55 on that.

It really helps if you know what top tube length you need. Of course, this varies somewhat from frame to frame.

Btw, the TT on the 52cm is still 54, again, a test ride is really going to help
you decide. Failing that, find a bike with that TT length that has similar geometry.

As others have pointed out, it all depends on your body measurements. I'm 5'8" and have been considering their 47 or 49. The measurement that is most important for me is the top tube length. My current bike, a 48 cm Redline, has a 52.1 cm top tube. A 54cm Kona has a top tube of 55.2cm which would be way too big for me. The best thing to do would be to test ride it to see if it would really work for you. I would be hesitant if buying from ebay or somewhere similar.

I would also add that stem length and bar shape make a big difference. I am 5'8" and have ridden a 54 and it fit very well, and I have a shorter torso. I don't count out a frame on a quick test ride if it feels reasonably close, a degree or two of stem rise and bars with tighter angles and shallow drops can make a huge difference without even changing stem length.

I owned a 2006 Kona Jake( brown. black and yellow) for a short period of time that I got at a great deal for $450.00. It was sitting in my LBS collecting dust so the owner cut me a deal. I picked it up and I never could get used to the stand over height. It was way to snug for my liking.
I'm 5'8 about 154lbs with a 29.5 or 30 inseam and I didnt like how it felt I had to leap over the bike. I know you never really plant your feet down while riding but it made me feel like the bike was rather tall riding. I sold it. I prefer smaller bikes for the sake of control and being able to plant your feet around quick corners on the local fire trails and the easy mount/dismount ina cross race. I guess the smaller compact frame allows me to have quicker response. It does tighten up the shouldering points yet riding feels good , But thats just me. Sold the bike, now i go with a 50cm or some times a 52.

I prefer smaller bikes for the sake of control and being able to plant your feet around quick corners on the local fire trails and the easy mount/dismount ina cross race.A smaller frame does not make mounting or dismounting a bike any easier, and having a bike with more drop from saddle to bars, and a shorter wheelbase, would tend to make it more difficult to control.

The 54 was a bit large for me. It seemed like I was riding a horse not a bike for the most part. I'm no bike expert but I would imagine the bottom bracket height paired with the seat tube length made out for the issues I was having. If I positioned my seatpost just right it was like I had to huck myself just to get back on. If I adjusted it a bit lower it I wouldnt get proper leg extension. I just couldnt get my seatpost dialed in. So now I just go with a frame that I can make minor adjustments in stem and seatpost length. I went from Kona to Bianchi so of course each company has there own description as to what they consider each size is. Overall the jake is a great entry lever cross bike. If I were to buy it again id go with a 52.

I'm 5'7" and I ride a 55 cm road bike. But I go down one size smaller in a cyclocross frame due to the higher bottom bracket. My 52 cm Bianchi San Jose is sized accordingly. Hope this helps.

I am 5'9 and wear 30inch inseam pants. I ride a 54 road bike AND a 54 Kona Major Jake. The Kona DEFINITELY feels much bigger. It rides more like a 55 or 56 road bike. BUT I LIKE IT THAT WAY. It is especially tall with knobbies (bumps into the boys when I am straddling the top tube). I have had absolutely no problems due to the large feel of the bike and in fact can ride it off road and clean obstacles that have some of my MTB buddies falling off behind me. Other than my first couple of days on the bike, I have NEVER wished it was smaller.
BUT, there is no question that it feels big for this 5'9" guy.

I'm 5'7" and I ride a 55 cm road bike. But I go down one size smaller in a cyclocross frame due to the higher bottom bracket. My 52 cm Bianchi San Jose is sized accordingly. Hope this helps.

The last 2 comments are the most useful, I think.
I will just add to them by saying that I ride 55cm road frames and 53cm touring/cross frames.

The discrepancy in sizes is due to the cross frame being slightly more elevated from the ground by the positioning of the wheels (allowing for wider tire clearance vs a road bike).

Yep. For comparison, I have a 54 cm Trek 520. The reason the smaller frame feels comparable is the fatter tires raise the bike to nearly the same height as the road bike so the going a size smaller is canceled out by the wider tires mounted on cyclocross/touring bikes.

There's a lot of hooey floating around here. When sizing a CX'er, the general thought is to go down one size from your road bike assuming the HT and ST angles are the same. If not, or if you are not coming into CX from the road, then, like any other bike, you want to pay attention to the length of the ST, HT and TT. The height of the BB (which is usually always higher than a road bike) has very little to do with correct fit other that it changes the HT and ST angles. The reason folks size down from road bikes has nothing to do with size of tires, BB height or standover height, but rather sizing down makes for a smaller cockpit and redistributes your weight/balance over the center of the bike to theoretically improve handling over rough stuff and off-camber parts of the course.

To get to your answer, a 54 Kona will have a 55.1 or 55.3 TT depending on the model year. It will also have a HT of 13 or 13.5mm and, of course, a 54cm ST. At least mine does. I'm 5'10" and ride a 55 road bike. I also have a 54 Kona Jake. I run a shortish stem and zero offset post to make my cockpit smaller, but the frame fits me perfectly. I hope this helps.

There's a lot of hooey floating around here. When sizing a CX'er, the general thought is to go down one size from your road bike assuming the HT and ST angles are the same. If not, or if you are not coming into CX from the road, then, like any other bike, you want to pay attention to the length of the ST, HT and TT. The height of the BB (which is usually always higher than a road bike) has very little to do with correct fit other that it changes the HT and ST angles. The reason folks size down from road bikes has nothing to do with size of tires, BB height or standover height, but rather sizing down makes for a smaller cockpit and redistributes your weight/balance over the center of the bike to theoretically improve handling over rough stuff and off-camber parts of the course.

To get to your answer, a 54 Kona will have a 55.1 or 55.3 TT depending on the model year. It will also have a HT of 13 or 13.5mm and, of course, a 54cm ST. At least mine does. I'm 5'10" and ride a 55 road bike. I also have a 54 Kona Jake. I run a shortish stem and zero offset post to make my cockpit smaller, but the frame fits me perfectly. I hope this helps.

I also see some hooey floating! You shouldn't switch your seatpost to adjust your cockpit. The reason you should use a zero offset seatpost would be to put your body in the correct position while pedaling. As in, knee over pedal (or close based on personal preference). If you have to run both a short stem and a zero offset seatpost to make the cockpit right for you then your top tube is too long for your reach. Simply put, your bike is too big.

I'd like to add, it's a common fallacy that moving to a smaller frame necessarily shortens the cockpit. The problem is that while the frame gets smaller, saddle height stays constant, so you need to use more seatpost. This moves the butt up and away from the handlebars. (Another way of looking at it, is that the headtube shortens, moving the bars away from the saddle.)

I also see some hooey floating! You shouldn't switch your seatpost to adjust your cockpit. The reason you should use a zero offset seatpost would be to put your body in the correct position while pedaling. As in, knee over pedal (or close based on personal preference). If you have to run both a short stem and a zero offset seatpost to make the cockpit right for you then your top tube is too long for your reach. Simply put, your bike is too big.

Wrong. I have short torso as compared to my femur length. My TT and ST lengths are appropriate for my body dimensions. I run 9cm stem instead of the Kona specc'd 10.5cm stem to accomodate my shortened reach. I choose to run a zero offset post because I am not so much concerned with the mythical KOPS position on my CX bike and am more comfortable with my saddle closer to the BB centerline. If I were to size down as you mistakenly suggest, the HT on my Kona would shorten increasing the saddle to bar drop. If you reread my original post, what I was addressing is the suggestions to the OP to size down because of standover height, BB height, or tire size.

First, what do you want to use the bike for?

Most of us use a CX frame like the Kona Jake for fun riding. We're not about to enter a cyclocross competition. LOL

Which is why I ask. If he's racing, the answer is going to vary a bit from him wanting a good commuter or cruiser. Not that the actual fit would be different, but the overall importance of the fit is a more critical in a racing environment than it would be for a casual rider.

Most of us use a CX frame like the Kona Jake for fun riding. We're not about to enter a cyclocross competition. LOL

:eek:

That's the position I was in when I bought mine, but then I entered "a cyclocross competition" and my whole view of things changed. Everyone who owns a CX bike should be required by law to try cross racing at least once, for their own good. Not doing so is like owning a pizza and using it exclusively as a frisbee.

The reason folks size down from road bikes has nothing to do with size of tires, BB height or standover height, but rather sizing down makes for a smaller cockpit and redistributes your weight/balance over the center of the bike to theoretically improve handling over rough stuff and off-camber parts of the course.


While I do not disagree with your view of the advantage of a smaller cockpit, you are also spewing "hooey", or whatever the hell you called it, when you say that sizing down has nothing to do with size of tires or standover height due to predetermined wheel clearances. This relationship in frame sizes is so obvious that all one has to do is put a road bike next to a CX bike with similar angles and dimensions to see what I am talking about. If you disagree, well, hell...

I went to the Dave Moulton site, and according to my body size, inseam, foot size, etc., I came up with 54cm as being my correct frame size. I have read where Kona Jakes run large, so I'm wondering if the 54cm is correct. Anyone have experience with these bikes?
I have a line on a used one.


54 should be about right. I am your height and have been comfortable on bikes from 52-55 cm. It will take some time to get the fit dialed in to your preferences no matter what advise anyone gives you on frame sizes.

While I do not disagree with your view of the advantage of a smaller cockpit, you are also spewing "hooey", or whatever the hell you called it, when you say that sizing down has nothing to do with size of tires or standover height due to predetermined wheel clearances. This relationship in frame sizes is so obvious that all one has to do is put a road bike next to a CX bike with similar angles and dimensions to see what I am talking about. If you disagree, well, hell...

Um, I'm not sure that I understand your point. I think we agree that tire clearances are greater on a CX bike than a road bike and that the BB's are usually higher, but you lose me on the standover height part. Tire size and BB height have little to do with bike fit (although BB height can impact chainstay length). The standover height is determined by the length of the tubes, the HT angle and whether the TT is sloping or not (few CX'ers do), but it typically does not factor into fitting for a either a road bike or CX bike. Unless you're doing dismounts incorrectly, or you ride the crosser over really rough stuff that requires you to dismount and straddle the bike, standover height is kinda irrelevant.

As far as comparing the two types of bikes side by side, I'm not sure that means anything as far as fit goes. The cockpits of my 54cm Kona SS Paddywagon and my 54cm Kona Jake are virtually identical even though the tube lengths, angles and BB heights are slightly different. Not sure how this helps the OP.

The standover height is determined by the length of the tubes,

While your analogy stands true if one were to compare only one form of bike (i.e., a road bike), but because we are speaking comparatively about two different (which has been the predominant argument in this thread) designs, road AND cx, then it is logical that your above quoted statement is wrong.

A smaller frame does not make mounting or dismounting a bike any easier, and having a bike with more drop from saddle to bars, and a shorter wheelbase, would tend to make it more difficult to control.
A small frame doesn't, but a properly fitted frame makes mount/dismount much easier.

[QUOTE=MerckxMad;8221955]The standover height is determined by the length of the tubes, the HT angle and whether the TT is sloping or not (few CX'ers do), but it typically does not factor into fitting for a either a road bike or CX bike.QUOTE]

I may be wrong, but I think bottom bracket height also figures into standover as well. If the bb height is higher on a given bike than another, and the tubes are the same length, would it not result in a higher standover?

It is also worth mentioning that many manufacturers of cx bikes are using what is more commonly referred to as American geometry. Meaning, the bottom brackets are lower than traditional European (Belgian) made bikes.

A smaller frame does not make mounting or dismounting a bike any easier, and having a bike with more drop from saddle to bars, and a shorter wheelbase, would tend to make it more difficult to control.

A smaller bike (combination of wheels and frame) does make a difference in mounting.

The amount of drop and wheelbase relative to control is subjective. What works for one doesn't work for another.

[QUOTE] I may be wrong, but I think bottom bracket height also figures into standover as well. If the bb height is higher on a given bike than another, and the tubes are the same length, would it not result in a higher standover? [QUOTE]

No, because while the HT and ST angles change (and possibly the downtube length), the standover height does not. For example, my Kona SS and CX have similar TT and ST lengths (2mm difference in TT), but the standover height is virtually identical (taking into account the diameter of the TT). I always believed that the BB height had more to do with clearance and possibly chainstay length than geometry of the main triangle.

It funny that you mention lower American BB heights because my (Belgian-made/market) Merckx frames have relatively low BB's compared to my other bikes.