Banded Krait

https://www.retul.com/

I got a Retul bike fitting done today. It was one of the most interesting, enlightening, and somewhat depressing, bicycling-related events in which I have participated.

I say interesting in that I work as a computer programmer. I am generally interested in technology. Now that I am bicycling, I am doubly interested in technology applied towards bicycling. The Retul bike-fitting system is very technology-oriented, in that it uses a high-tech infrared sensor device to make minute (down to the millimeter) measurements of key biomechanical parameters affecting one's fit on the bike.

I say enlightening because the end result was that I learned far more than I ever thought possible about my biomechanical parameters and what I require for a good fit on a bike. Sure, I might have been able to obtain these on my own over a very extended period of time by trial and error, but I was able to learn these in less than three hours today by engaging this service.

I say depressing because I found out that I bought the wrong size bike when I bought my new road bike in April of this year. This was despite choosing what appeared to be the most competent and professional of all the bike shops I visited during my extended purchasing odyssey. If the results of the Retul bike fitting are to be believed, the bike shop where I bought my bike was incompetent in conducting the measurements which led them to recommend I purchase a bike in the size I did (52 cm frame). According to my Retul bike fitting, I require a 54 cm frame. The results of the analysis are so striking that I think it would be hard to refute the argument. In addition, the analysis seems to provide the hard-core data to explain some serious problems I have been having on the bike almost from the time I started to ride it (serious problems with numbness of the hands).

Now what to do with this information? In an ideal world, in which one has chosen the correct frame size, one may have to make minor adjustments + or - around the default settings. In my case, the bike fitter had to make a huge adjustment in my seat height--he raised it almost 4 cm. Next, he raised the handlebar height as much as he could to compensate, but with these modern threadless handlebar systems one is somewhat limited as to what one can do in this area. My assignment is to go on a number of short-to-moderate rides over the near term future to assess how well these adjustments are working. The question I am asking myself is, "What happens if these adjustments don't do the trick?" It all seemed so much simpler almost 40 years ago when, as a 15-year old teenager, I bought my first road bike (a Peugeot UO-8). Nowadays, high-end road bikes are so expensive it seems like there is little room for error. All I know is that, if I cannot get comfortable on this bike, I am going to be seriously disappointed.

BluesDawg

Ouch! I hope the adjustments help. I'm sure you have posted this before, but for the benefit of some of us old farts with poor memory, what kind of bike do you have and what are your height and inseam (pubic bone height, not pants size)?

oldster

+1,very curious....
Bud

richjac

I had a Retul fitting done last week, after it was recommended by three of my friends who had done it this Spring. The only thing that was not changed during the fitting was my saddle height - I guess I had that right. If I were shopping for a new bike, I would go with a smaller frame size, as the top tube length and height of the head tube don't allow much leeway for further adjustments - which were to bring the handlebars closer but lower. I am much more comfortable on the tops of the bars as well as on the hoods - less strain on the neck and shoulders, less pressure on the hands. I'll see how it goes after the next three weeks leading up to a Century on Sept 11th.

bruce19

Me too. Also curious about cost.

KillerBeagle

I had a Retul fit done a few months ago for $250+ and was very disappointed. The adjustments were small and only to the saddle height, angle and fore/aft location, and cleat location. They did not improve my main issue, left hand numbness, in the least. Knee pain on my post-surgery right knee actually increased so I went back to my old saddle height.

I think the results depend on the skill and care of the operator. I wouldn't do it again.

AzTallRider

I'm curious about some of what you are saying, BK. You say hand numbness is the big issue, and that you need a larger frame. The two biggest things the larger frame would do is raise the bars, and likely push them further forward. Raising the bars certainly can relieve pressure, but IMO, the more critical factor is the relationship of the saddle to the pedals; the oft-discussed Knee Over Pedal Stem (KOPS), and where you are in relation to that position. The further behind the pedal you are, the less weight on your hands. But just like raising the bars, that works against performance, as you want to be as forward as you can without putting too much weight on the hands. If it is right, you should be able to pedal moderately hard in the drops (best done on a trainer), remove your hands, and be able to hold the position for a few seconds, without banging your nose on the stem.

So all this makes me really curious as to where the Retul fitting placed your saddle relative to KOPS, and also whether they increased your stem length to stretch you out the way a larger frame would.

volosong

Exactly! Did they try different stem lengths, and different angle stems? I think one can get zero degree, plus/minus 6 degree, and plus/minus 17 degree stems. If those don't work, there are adjustable stems, (at a higher weight cost), that will adjust to whatever is best for your body. Not sure if adjustable stems come in different lengths.

A one-size smaller frame than optimal should be able to be adapted to your body easily. Adjusting a larger frame down is a lot more difficult.

- - - - -

Somewhat related...my bike has been very comfortable to ride. Centuries are no problem. Then the other week, I had a new handlebar installed as I prefer the traditional shaped bars over the newer ergonomic shaped bars. With the new bars, I couldn't go a 1/4 mile before my hands were hurting and became numb. Played with different adjustments last night and finally hit a sweet spot by raising the seat 5 mm and lowering the handlebars 1 cm, (move a spacer ring from under the bar to on top of the bar). Raising the bars, (by flipping the stem), didn't help a bit. I'll take a longer ride tonight to make sure I did indeed get the adjustments correct.

Banded Krait

I am attaching an analysis completed by the "bike fit calculator" at the Web site competitivecyclist.com. I had to take 8 measurements and key these into the calculator. It then spits out bike fit recommendations in three different geometries: Competitive (aggressive), The Eddie (Merckx) Fit (moderate), and the French Fit (relaxed). The bicycling inseam measurement is the pubic bone height measurement (84 cm).

My bike is a 2010 Gary Fisher Cronus.

I see that the results from the Competitive Cyclist's bike fit calculator seem to jibe with the results from my Retul bike fitting: I should be looking at 54 cm frames.

John_V 

KillerBeagle,

Sorry to hear that you had a bad experience with your Retul fitting. I had a Retul fitting in November, just after I bought my road bike. I just can't seem to say enough about the fitter or the results. I was lucky to have bought a bike with a frame that actually fit my size. The fine tuning was all that was needed and the end results were perfect for me. It took 3 sitting (1 to 1 1/2 hour each) and around 3 months for the complete fitting, including adjusting the shifter/lever to fit my hand position on the handle bar. That was something I have never heard anyone tell me that their fitter did during their fitting. I actually thought that my bike fit was not that bad before I did the Retul fit and attributed the aches and pains to learning to ride in a different position. I was so wrong that it wasn't funny. My riding experience after the fitting has been fantastic and if-and-when I get my next road bike, I'll be back for another fit.

CraigB

So you're 5'-9" +/- and the shop put you on a 52? I'd loved to have heard their reasoning for that. I'm 5'-10" and all the shops I visited, and all the fit calcs I've ever run put me on a 56.

Banded Krait

That is what, in hindsight, has me so perplexed. The shop where I bought the bike seemed to be the most professional. Of the six shops I visited during my purchasing odyssey, it was the only one where the personnel put everyone who is seriously thinking about buying on a trainer and do a detailed basic fitting. It took about 40 minutes. They measured my knee angle during various points in the pedal cycle. They used a plumb line to determine the fore-aft positioning of the saddle. I just don't know how they got it wrong. Was the individual who did this basic fitting incompetent? That's what I am left to conclude. I find it so ironic that two of the shops which used what I refer to as the "eyeball technique" (meaning they just looked me over and asked me my height) actually recommended the correct size frame. Some of the other shops just seemed interested in pushing whatever bikes they had in stock at the moment regardless of whether they fit me or not. In that kind of environment it was easy for someone like me who had not been on a bike in over 35 years to make a mistake--a costly mistake.

bgross

I hadn't bought a sport coat or dressy clothes in over 25 years when I walked into the men's store (in my usual shorts and tee shirt). A salesman approached. I explained my need for some "resort casual" clothes for our upcoming cruise and hoped that he could help me.
He walked me over to a rack of sport coats, looked at a couple and selected one for me to try on. It fit like a glove. Then he selected another... and two pairs of pants, shirts, shoes, ties, belts....
Everything fit perfectly (yes, I tried it on and had the pants hemmed) and he never touched a tape measure -- he just knew, using the "eyeball technique", and his years of experience. Pretty neat trick, considering that I wear a 16 1/2 - 37/38 dress shirt.

I guess technology is good, but there are other ways.

Hermes

I had the Retul fit done on my road and time trial bikes. It is a dynamic fit. That is it shows the dynamic position of your knee while cycling in relation to the pedal axel. It also shows the plane the knee takes. Some riders' knees go out and some move around. My fit was really close so the adjustments were small.

If the frame is too small, the seat to bar drop will be too great for the handlebar height without using a highly angled rising stem. If you observe pro bike riders on TV their stems are long since they go for smaller bikes to get a better seat to bar drop.

I liked my Retul fitting and think they are very good. However, many bike shops are clueless about fitting people on bikes.

IMO, we should not allow any bike fit discussion unless the OP posts a pic of he/she on the bike. Guessing what a rider looks like on the bike and commenting is..... what it is.

t4mv

What brand/kind of frame are we talking about, here? Is there a diff in ST measurements? Sloping vs. level top tube? Like Hermes said, it's a little hard to say how far off a 52 is from what's recommended for you. You'd probably look pro on a 52 if you really needed a 54, with a long stem to boot, but without seeing the bike's set up it's a little difficult to tell how far off you are.


OK, never mind, 'found an earlier pic of your bike:


So, the seat height is now 4cm higher, the stem is probably at the end of the steerer, and the first few rides after the Retul are....? What was uncomfortable about the fit as pictured (that presumably led to the Retul fitting)?

GFish

I'm apx. your height and believe a 53 is actually the perfect size. I also heard it's better to be a little under then over in size since seat offset and stem length adjustments will dial in the fit. So perhaps the shop isn't really that far off. Have you tried different stem lengths?

ThatBritBloke

Top tube length is more critical than seat tube length. It's easy enough to adjust to leg length/offset, not so easy to adjust top tube length other than by swapping the stem, but extremely short or long stems will affect handling.

Three people of the same height may ride quite different size frames according to the proportion of leg length to torso. Given the fact that one manufacturers 56cm frame is another's Medium, besides the fact that sizing is frequently notional now that the horizontal top tube is getting rare.

I'm 6'3" with a 36" inseam. My colleague is the same height with a 33" inseam. I ride a smaller frame size to account for my shorter reach. He rides a larger frame despite having shorter legs.

Anyway, in the end it's how you feel while riding your bike. A computer programme may crunch the numbers, but not adjust the reach of your brake levers. The numbers are right ... maybe it's you who's wrong? On the other hand guessing your inseam and watching you ride around the car park does not constitute a bike shop bike fit.

berner

Good discussion. I'm taking it all in as I've been having increasing amounts of hand numbness with no resolution. After trying every conceivable combination of saddle and bar position, the problem persists. I'm left with the notion that a 'full on' professional fit is the only option. It's good to know that many, if not all, have had good results.

DnvrFox

Does he bicycle?

Bob Ross

Well, here's your out:

You know those "down to the millimeter" measurements that Retul allegedly is based upon? Those are entirely dependent upon precisely locating the sensors on your body's landmarks..and guess what? Without an x-ray or MRI, even the best biomechanical professionals can't reliably locate those landmarks with that same degree of precision that Retul uses. So while the Retul system can indeed say "It is exactly 24.3 cm from the sensor on your knee to the sensor on your ankle", if the fitter removed those sensors and then tried to replace them in the exact same locations, it is extremely unlikely s/he could, and so the next time Retul tried to measure your tibia it might come out to 24.2 or 24.7 or 25 cm.

iow, before getting completely depressed consider getting another fitting.

Banded Krait

Bingo. This is what the fellow who performed the Retul bike fitting emphasized. Seat tube length is less critical because one has a lot has a lot of options in raising or lowering the saddle. Sure, one can try different stem lengths and angles, and one can add or remove spacers to adjust the handlebar height, but in general, one is much more constrained in these areas. This is why it is so important to get a frame of the correct size in top tube length.

Besides the hand numbness, the other problem I've been having with regard to fit is stability. The bike just doesn't feel stable when I put all the spacers in and set the stem with the angle up. This is further evidence that something is off in my reach to the bars.

Banded Krait

I certainly understand that if I were to repeat this fitting, there would be minor variation in the results. That is inherent in all measurement.

But it is the big picture results I am focusing on. For instance, one of the key measurements is knee angle at the bottom of the pedal stroke. My "before" knee angle was a ridiculously-constrained 55 degrees. This jibes with what I was feeling out on the road. In my youth, I was a great hill climber; now, on this bike, I struggled to go up every hill.

In general, the results of the bike fitting seem to correlate very well with what I was experiencing on the bike. It is just unfortunate that the cause of the problems appears to be a bike with an incorrect frame size for me. If this is fundamentally wrong, one is limited to how much adjustment is possible.

Banded Krait

I am still waiting to receive the full written report from the bike fitter. But if I recollect correctly, I was way forward in my position over the pedal. Since I don't remember the actual numbers, I am not going to post anything here. Needless to say, it was further evidence of a too-small frame and another factor causing too much weight forward and the resultant numbness in the hands.

bruce19

Like many, I have always tried to get all the "right" mathematical info when buying a bike and setting it up. When I first started this I was about 40 yrs. old and 5'10" with a 32.5" inseam crotch to floor barefoot. The math said I should ride a 54-55 cm C to C frame. And, I did. Comfortable...quick...good handling...solid braking. Then at age 50 I got out of cycling for 8 yrs. When I got back into cycling there were sloping TT bikes...more CF, AL, TI and combo frames than my old steel MAZA. Gone were my Athena friction shifters. I bought a LeMond TI with a Triple crank. It was a 54. I was now 5'9" with the same 32.5 inseam. After a couple years I got a MASI Gran Criterium S with a sloping TT. My trusted bike shop owner said it was the right size. I rode it. I liked it. I had to change the 110mm stem for a 100mm stem. Set up the saddle height and fore-aft as I always had and the bike was perfect. Comfortable...fast...etc. I love this bike. Then I measured it using the "virtual" frame measurements. It turns out it's a 57 cm C to C frame with a 57-58cm TT. What!? Am I supposed to dump it and buy a 54 frame? Nah. I'm having fun. Spinning effortlessly at 95-100 rpms and doing my 15 mi. TT faster than I ever have. Think I'll just go put my tape measure away and ride.

CraigB

Are you saying that the angle formed by your upper and lower legs was acute while your foot was at the bottom of the pedal stroke? Or do you mean your lower leg was at 55 degrees to a straight line extending from your upper leg (which would put that back-of-knee angle at 125 degrees)? I must be missing something, which is entirely possible - I frequently do.