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Did I also buy a bike that's too large for me?(32 posts)

Did I also buy a bike that's too large for me?NewDayNewWay
Dec 14, 2002 10:26 AM
I don't think I'm in as problematic a situation as the guy who posted about his giant, but I've been riding my bike for about two months now and "feel" that it is a little too large for me. I'm wondering, however, how much of this is simply not being used to a road bike (I come from a MTB background) and if this is easily resolved by buying a shorter stem.

I'm about 5'11" with a 34" inseam (determined using the method where you push a book up into your crotch as hard as you can). I bought a 58 cm Trek 2300. Here are my observations about the fit...
* When I stand over the top tube with both feet on the floor, the top tube is just touching the crotch of my bike shorts. This may be fine, but it does hint that perhaps a 56 cm would have been a better choice
* If I put my seat all the way forward, and drop a plumb line from the front of my knee, the plumb bob is about 1.5 cm behind the pedal spindle. However, again this may not be a problem. I actually started out with my seat way back because I was used to cranking at a slower cadence on my mountain bike, but have since learned that I should pedal at a fast cadence. As a result, I found it better to move my seat more towards the front, but not all the way. I'm most comfortable with my seat NOT all the way forward, but back about 1 cm more, so the plumb bob is back about 2.5 to 3 cm behind the pedal spinndle
* I tend to move forward in the seat as I ride and expend a fair amount of energy keeping my butt back. My current conjecture is that this is due to the possibly long reach to the handle bars. Also, my arms get very tired from the weight of my upper body, however, I'm not sure if this is just because I'm not used to road biking.

So, in a nutshell, I'm not sure if the first two points are an indication of a problem, as I think I'm OK, but I'm pretty new at this, so I'm not certain. The third bullet seems to indicate that I should buy a shorter stem. The current stem is a 7 degree rise 110 mm. I was thinking of going down to a 7 degree rise with a 80 mm length.

Please advise, as I've been fretting over this for quite some time!
re: Did I also buy a bike that's too large for me?rdbkr
Dec 14, 2002 11:56 AM
All of your observations seem to indicate that the frame is too large. You'd like to keep the stem somewhere between 100mm-130mm, to stay in the "sweet spot" handling-wise.

I would test ride the 56cm to see if the handling improves. My guess is that it will.
I do not necessarily agree, but...eflayer
Dec 14, 2002 12:04 PM
I am just starting to like bigger bikes. With similar body, I ride either a 58 or a 60 and like it a lot. Weight on hands is often due to bars being too low. To get em up, you need more head tube, more stem height. To get this you often need bigger frame.
re: Did I also buy a bike that's too large for me?eflayer
Dec 14, 2002 12:01 PM
I'm an old guy so my issues could be different than yours. I am also about your height and crotch. One measure you do not reveal is how is the relationship of saddle height to handlebar height. If you measure from the floor perpindicular to top of middle of saddle and from floor to top of bars at stem, that would be interesting to know. I'd guess an aspect of your discomfort is due to your bars being too low. I would no longer consider riding with bars any lower than even with saddle. I'b be interested in these measurements on your bike.
re: Did I also buy a bike that's too large for me?NewDayNewWay
Dec 14, 2002 2:49 PM
It's 38 and 3/4 inches from the floor to the top of the saddle and 37 and 1/2 inches to the top of the handle bars.
Don't think so.look271
Dec 14, 2002 12:06 PM
You are about exactly the same size as me. My inseam is slightly shorter (33 inches). I currently ride a 58cm frame, and was fitted at a biike shop. I have a + rise stem of 100mm. Perhaps going with a 90 or 100 stem and moving your seat ahead somewhat would take care of it. A new frame is a bit extreme.
Frame size is not frame sizeKerry
Dec 14, 2002 1:06 PM
You have to be careful about simply stating frame size. Some measure C to C, others C to T, and some even C to top of seat collar. There's an easy 3 cm difference in those measures. While standover height is not everything, there should be some clearance. In a person this tall, 1" of clearance is reasonable unless there are some unusual body proportions - an example might be short legs relative to torso requiring a long top tube and the long seat tube that comes with it. However, at 5'11" (1.8m) and a true 34" (86 cm) inseam, this person seems pretty normally proportioned. His frame is too big.
Frame size is not frame sizeDaveG
Dec 14, 2002 1:17 PM
Trek measures their bikes from center of BB to the top of seat collar so a 58 Trek is a bit smaller that a "standard" 58 c-t bike. This would seem to be about right for a 86cm inseam. Something seems amiss though as Trek lists the standover height as 81cm, which should leave plenty of crotch room for an 86cm inseam.
Frame size is not frame sizeNewDayNewWay
Dec 14, 2002 2:52 PM
Rechecked my inseam. Either I'm shorter now or my previous check wasn't accurate. It's 33 and 1/2 inches.

Frame size is not frame sizegtx
Dec 14, 2002 3:10 PM
This topic comes up a lot--people getting the wrong size/having trouble fitting Treks. So you're not alone. And if you look at how some of the pros on Postal have their bikes set up you'll notice some of them have done some pretty extreme stuff with seat posts, stems, spacers, etc. I have pretty much identical proportions as you, and could have gotten one of these bikes for almost nothing when I worked in shops--but didn't. The 58 felt too big and the 56 too small. For now I'd try putting on a 10cm stem and see how that feels. An 8cm stem will mess with the handling. Good luck.
why too big?eflayer
Dec 14, 2002 1:18 PM
This is a topic of much interest to me. Why do you think this would be too big? What's too big about it? If the contact points feel good and the looks don't seem weird, then what would be too big about a 5'11" person on a 58?
If that's so, then so is mine.look271
Dec 14, 2002 6:04 PM
But it's not. I'm assuming his is c-t, like mine. Yes, he probably could go to a 56 or 57, but a stem swap is cheaper and easier than a frame swap, isn't it?
NOT TOO BIG !!!!C-40
Dec 15, 2002 5:38 AM
Most of the folks responding to these posts don't bother to look up the geometry before posting a response.

The 58cm Trek is equivalent to a 56cm measued center to top. Either of the standard formulas used to determine frame size would suggest an even larger frame size of 57-58cm measured center to top: 86cm - 29cm =57cm or 86 x .67 = 57.6cm.

The standover height of a 58cm Trek is only 80.7cm. That leaves over 5cm of standover clearance. 3-5cm of standover clearance is normal and adequate.

If the poster tried a 56cm Trek, he would find that the .5 degree steeper STA would move the nominal saddle position .6cm forward. The steeper STA on the 56cm also makes the TT length only .4cm shorter than the 58cm. Not enough to make a significant change in the fit.
one other thingeflayer
Dec 14, 2002 12:16 PM
Bike shops are notorious for selling "racer boy" style bikes to everyone. You indeed may be a racer. But if not, I would guess that huge percentage of riders would be happier riding and more comfortable on their machines if shops would sell bigger bikes. Bikes look cool with high saddles and low bars, but they are a pain to ride like that.
one other thingNewDayNewWay
Dec 14, 2002 3:01 PM
I'm definitely not a racer!

The one thing that is reassuring in all this is that I have 4 cm of spacers. If I had a 56 cm bike, then I would need almost exactly 6 cm of spacers to have my seat at the same height and the handle bars at the same height relative to my saddle, with the same stem, and that would seem quite extreme. I suppose I could have, say, 4 cm of spacers and a stem with a higher angle of rise, but would that not still seem a little atypical?
trial and erroreflayer
Dec 14, 2002 3:13 PM
Stem rise is another confusing subject. Is your stem then at approximately 80 degrees and just a bit above parallel to the ground? You could go to 90 or 100 without having it look weird in my opinion. You might find that higher will make you more comfortable. You would need to come up almost 2.5 to get even with saddle. Just remember as things come up higher they come toward you more, and then you might need a bit more length too. I currently have a bike where my bars are 2.5 cm above saddle and I really like it. Comfortable on top and comfortable in the drops!
Try this firstTig
Dec 14, 2002 1:05 PM
When I hop back on my MTB it always feels too short (as in top tube) compared to my road bikes, even with the seat back and a long stem. I'm not surprised to hear you feel too stretched out on your road bike. I'd avoid the jump from a 110 to an 80 though. Way too much of a change, and it will mess up the handling. There are other things you can do before you try a 100 mm or smaller stem as well.

First, regardless of the reach to the bars, make sure you like your seat placement. Set it where it feels best to pedal with for your style and needs.

Next, check out the up/down tilt of your handlebars. From the side, are the drops (flat part of the lower bars) pointed where the ends are pointing upward and not parallel with the ground, or better yet, pointed down slightly. Many people like their bars to be slightly angled as if they wanted water to roll back and drip off the ends. This helps set up the upper curved section to be easier to reach, as well as putting the brake hoods up and back a little.

Brake hood placement: This is also a personal choice. You'll see many people, including pro's such as Lance, with their brake hoods fairly high up on the bars. This puts them in an easy to reach position since most of the time people ride holding them. You can move them up a little bit without having to remove the bar tape. If the brake hoods are too high, they rotate the brake handles out and away from the bars, making it hard to reach them when your hands are in the drops.

If this feels better but you are still sliding toward the nose of the saddle, try angling it nose up ever so little. You'd be amazed how a little nose up can fix this, as well as prevent numbness down under.

Still not good enough, but better? Try putting a narrow spacer or two (if you have enough steerer tube left) under the stem. If you feel there is enough bar height already, go with a 100 stem. If you need anything much shorter, you may need a smaller frame after all... but wait! As we ride and our backs get stronger, we gain flexibility and can enjoy stretching out toward the bars. It would be a shame to replace the frame and then after getting stronger and more flexible, needing a longer stem this summer because you need to stretch out! Over the years I've gone from a 110 to a 130.
Try this firstNewDayNewWay
Dec 14, 2002 3:16 PM
Very interesting ideas...

I see now that the lower bars are angled down slightly towards the back, but not drastically. I'll adjust them so the downward angle is just slightly greater and try this out on my Sunday morning ride.

I have trouble reaching the brakes from the drops, although this may just be a function of getting used to doing this. I might also prefer to have the brake hoods a little higher. I'll consider this for next Sunday's ride.

In regards to the seat angle, I am finding this to be a balance between keeping myself stable in the saddle and comfort down under. I have a feeling that this is all going to lead to a saddle purchase sometime in the future.

I also wonder if my cloths are a factor. For winter riding I put on about four of five layers which constrains my movement on the bike a little. When I test rode the bike it was actually quite warm out and I felt that the bike was a perfect fit. However, a lot has changed in my riding style in the past two months, so it's difficult to draw any conclusions until the weather warms up.

Thanks for a lot of good suggestions.
re: Did I also buy a bike that's too large for me?DaveG
Dec 14, 2002 1:23 PM
a 58 Trek would seem OK for an 86cm inseam, unless you are measuring differently than the way Trek sizes (BB to seat collar). However, that seems like too little crotch clearance. Re-check your inseam again, making sure you are barefoot and book is straight. Get a good friend to help is possible. On your second issue, frame size does not affect saddle setback - only seat angle affects that. Assuming your seat height is a constant, frame size does not affect the location of the seat relative to the BB. Perhaps you need a steeper seat angle.
re: Did I also buy a bike that's too large for me?maximum15
Dec 14, 2002 3:06 PM
I also have a 58cm trek 2300. I am basically the same size as you. I have had to shorten the stem considerably to be comfortable. Actually, I thought I was comfortable until I bought a second bike with a shorter top tube. Now I have went to a 110mm stem and staight seatpost on the Trek. I am violating some KOPS rules, but I like the bike much more now. You may want to play with stem length and KOPS. I tried a 56cm trek and it was wwwaaayyy tooooo small.
Get a Seatpost with No Setbackjtolleson
Dec 14, 2002 3:47 PM
The fact that you can't achieve KOPS indicates to me that you may have a good shot at just resolving this with a change in seatposts. Also, some saddles have longer rails (allow for more fore-aft mobility) than others.

If you can get your saddle position closer to Knee Over Pedal Spindle, that alone will reduce your effective TT by 1.5 cm, which is no small matter.

I'd bet dollars to donuts that such a change will resolve your problem.
Yeah, that and...Matno
Dec 14, 2002 4:15 PM
adjust your saddle angle just right. You may have to get a different saddle, but nothing will put weight on your arms like a saddle that tilts too far down. The stem length also makes a difference, but not as much, IMO. I went from an 85mm stem to a 130mm without noticing a huge difference in arm fatigue. (I finally settled on 110mm). Changing my saddle angle just a few degrees made a huge difference.

I know everyone else has already offered a million opinions, but I too am exactly 5'11" with a 33.5" inseam. I ride a 56cm Schwinn that often feels too big. I really should go with a no-setback seatpost, but instead I just use the one I have with the saddle ALL the way forward. Works okay. Good luck!
Standover height is not a good indication of fit!gogene
Dec 14, 2002 4:46 PM
I'm with eflaye,r all the way, regarding his comments on 'bigger' bikes often fitting better. KOPS is also just a starting point. There is NO set fitting formulae, other than what feels good to you. It does sound like the poster might need some professional help.

Winter clothing does alter your sensations about correct fit. When wearing cold weather clothing, you are pretty much bound up and somewhat constricted in your movements, and your bike will feel too large.

I just sold a 56cm bike and I'm movin' up to a 60cm. I want to get the bars higher, more or less even or slightly higher than the saddle. The "boy racer" image is great if you have the flexiblity and don't mind the pain of being all wadded up on the bike. But for this dog, I think I'm subscribing to the Rivendell school of fitting.
Get a Seatpost with No SetbackNewDayNewWay
Dec 14, 2002 6:35 PM
I think you hit the home run with this suggestion!

A confounding factor is that I think I put my seat higher than someone else with the same dimensions. The reason is that I'm a "toe peddler", or so I've been told (i.e., I angle my foot downwards at the bottom of the pedal stroke.) That's way my seat is still higher than my handle bar height even with 4 cm of shims even on my 58 cm. So as I move my seat forward, I move my seat height up accordingly, which puts me even higher about the handle bars as I get closer to KOPS. But that seems to argue that in fact a 56 cm would NOT be right for me.

Anyways, thanks for a great suggestion! Despite the different opinions on this, I'm feeling better that I made the right choice and that there are just some adjustments that need to be made that will solve the problem.
sometimes a real good bike fitter can helpeflayer
Dec 14, 2002 7:05 PM
For about $50 a good bike fitter could put you up on a trainer or fit kit and probably do some measuring, questioning and watching you pedal and make some adjustments that might surprise you. I did this once and got the seat moved back about 1 cm and the stem changed out for one 1 cm longer and I was blown away by how good the bike felt after that.
I agree with Jtbianchi boy
Dec 14, 2002 8:03 PM
I am about the same height and inseam as you, and a 58 would be the right size for me in a Trek. The problem is that Treks have a relatively long top tube for that size frame. You can compensate with a shorter stem and/or a seatpost with less setback. Since your knees are 1.5 cm behind the BB spindle, it sounds like the seatpost would be the first thing to change. Different saddles also have more or less setback. Some saddles with a more forward position include a San Marco Regal and Brooks leather saddles. I don't think have a 56 Trek frame would solve your problem because then you would have too much drop from the saddle the handlebar and needs even more spacers.
Dec 15, 2002 5:56 AM
First of all, the size of this frame is not too big. The standover height of a 58cm Trek is only 80.7cm or 31.8 inches. Check this dimenion to be sure that you truly have a 58 and not a 60. This standover height gives you over 2 inches of clearance to hard crotch contact in bare feet. That is plenty of clearance.

How high is your saddle above the top tube (measured vertically? If it's 17cm or more your frame is most certainly not too large.

You mention the stem angle that you are using, but neglected to mention the amount of spacers under it. If you have any spacers the frame is not too big.

What's the vertical height difference between the top of the saddle and the top of the bars? Measure each from the floor and take the difference between the two measurements. 5-10cm is the common range.

Have you ever checked your knee to elbow clearance when riding with your upper back horizontal and your hands in the drops with the finger in reach of the brake levers? This is the most meaningful check for excessive stem length. All you need is enough length to keep from hitting your knees and elbows together. Some riders tolerate a small amount of knee to elbow overlap.

You KOP adjustment doesn't sound too bad. I've always had better luck with the knee positioned at 1-2cm behind the pedal spindle. If you want to experiment with a more forward position, you may need a different brand of seatpost that will permit a little more forward movement. If you post the brand of seatpost, I may be able to suggest an alternative.
Dec 15, 2002 10:06 AM
I'm at work now (sigh) so I can't check if I actually have a 60 cm or a 58 cm, but I'll check tonight. If I straddle the bike while in my socks, I think I can lift it about and inch and a half off the ground if I pull up fairly hard.

Not sure about height of saddle above top tube. Will check tonight.

I have 4 cm of spacers, which is what came with the bike.

Vertical distance to saddle from floor: 38 and 3/4 inches. Vertical distance to top of bars: 37 and 1/2 inches. So the saddle is about 1 and 1/4 inches about the top of the bar.

I have not check knee to elbow clearance. Will certainly do so tonight.

In regards to KOP... I did my Sunday morning ride (about 30 miles at a 15-17 mph pace) with my seat as far foward as it will go (about 1.5 cm behind KOPS), and raised the height of the saddle accordingly. End result: knee pain. In general, as I've moved my seat further towards the front over the past month to try and get close to KOPS, I've been more prone to pain in both knees.

So I'm moving my seat back where it was, so that I will be about 3 cm off from KOPs, as that's just where I feel most comfortable. I've always been suspcious of KOPS and it's never seemed right for me, either on my MTB or on my road bike, although I keep thinking that I'm a beginner at road riding and maybe I just need to get used to it. But I don't think knee pain something that can be disregarded under any circumstances, so I'm going to go with what feels best. Of course, this would mean that I can nix the new seat post, and work on the stem. My most recent thought was to set up the stem and spacers so that the bars are moved back horizontally about 1 cm (maybe more, but I see the point about steering issue if this is too short) and up about 1.5 to 2 cm vertically.
saddle position and more...C-40
Dec 15, 2002 2:47 PM
Adjustments to the saddle fore-aft position should generally not be made in large increments. You mnetioned that you adjusted saddle height "accordingly" after moving the saddle forward 1.5cm. "Accordingly" should be up 1/3 the amount that you moved it forward (.5cm).

Moving the saddle forward should not have caused knee pain. Generally, moving the saddle forward will enhance cadence (you'll spin faster), but reduces the amount of torque that you can comfortably apply. Be sure that your knee pain is not being caused by the most common beginner's mistake - insufficient cadence. I passed a half dozen slowpokes today who were all pedaling a 60 rpm or less. Keep in mind that power = torque times cadence. If you don't spin in the 90-100 rpm range, you'll have to apply a lot more torque to produce any given amount of power.

Check your leg position at the bottom of the stoke to be sure that you don't have the saddle too high or too low. You should be able to drop your heel at least 2cm below horizontal with you leg locked out at the bottom of the stroke (when clipped into the pedals). If you can just get your heel down to horizontal, the saddle is too high.

As for those stem spacers, 4cm is way more than most folks would ever use. You'll catch snickers from experienced riders with a setup like that. If you really feel that you need the bars that high, you should consider flipping the stem upside down to change the angle from 80 degrees to 100 degrees. This should raise the bars 2-3cm and allow you to move most of the spacers (temporarily) above the stem. Flipping the stem will also shorten the reach by about 1cm. If this height and length work, you can remove the spacers above the stem and shorten the steering tube.

You are likely to grow into a longer reach and lower bar position as you become more experienced.
C-40, some clarificationmainframe
Dec 16, 2002 8:07 AM
When clipped in and at the bottom of the stroke, are you saying locked out at the knee? That wouldn't seem a proper position at the stroke's bottom or am I misunderstanding what you're saying?
Dec 16, 2002 9:49 AM
Dropping the heel well below horizontal with the leg locked out merely insures that during the normal pedaling stroke the heel can remain relatively horizontal with some bend in the knee. It also insure that you're not being forced to pedal in a toes-down position at the bottom of the stroke. It's not intended to be a normal pedaling position.

I learned this trick after falling for the poor advice of raising you saddle until your hips rock. I'm flexible enough that my hips didn't rock until my saddle was set much too high for the best power output.

I find it much easier to judge heel drop than the angle of the bend in the knee at the bottom of the stroke. This method is more likely to result in a saddle height that's too low, IMO.
Dec 16, 2002 10:57 AM
I gottcha. Incidentally, I built up the Look this past week using some parts from the Lemond and others new. The redux results the following: Seat top to TT reduced from 19.4cm to alittle over 17cm. Went from a Thomson 80 x 120 to a Thomson +5 x 130 which eliminated my 1" of spacers but reduced drop from 3.75" to 2.25". You may recall frames are 55cm. On my maiden ride yesterday, even given these seeming curious dimensional results, the bike felt the same. Having been blindfolded, I doubt I could have discerned much as regards fit and geometry. Pedal/leg relation remains as before and elbow and knee the same as well. Rode hard with no pain right out of the box. Lingering question is should more drop be re-introduced by way of another stem (ITM adjustable?) I would have thought loosing 1.5" of drop would be very noticeable, not so. Reach seems about the same. Comments? I'll leave the comparison of steel vs. carbon for another discussion.