Road Cycling - Is There a Optimum Size Stem? and Other Newbie Questions

New to cycling and got a couple of questions. I maybe should ask these at the local LBS's but when they are making statements like, "Aluminum last much longer than steel because it has a much higher fatigue limit", I am not sure how much faith I should put in their response. It is kind of obvious all his in stock bikes were aluminum.

Since I am Height 184cm, Inseam (Pubic Bone Height) 86cm, Reach 62cm most of the programs recommend something around 58-59cm ST C-T with a total reach of 69cm. I know the formulas don't work for everyone but I need a starting point.

1. Is there a certain optimum length stem for a certain frame?

2. What are the drawbacks to say a 55cm TTL + Long 140mm stem vs 60cm TTL + Short 90mm stem?

I would assume that a short TTL+LS would be very twitchy compared to a Long TTL+SS which would be more stable but less responsive.

3. Should I just look for a frame that would end up the correct length with a 120-130mm stem?

4. During test rides how do I tell the difference between a frame that just isn't going to work for me vs bad set-up?

I have found a LBS (20 ml away) after 4 tries that actually seems willing to work with a newbie and get the set-up right.

He is recommending I try a Felt F80 (F75 replacement) 58cm with a 577.8mm A-TTL, 58cm E-TTL, 110mm stem, Tiagra equiped, priced at $750. He has F90, F65, F50, F45R, F35R, various Fuji's, + some 56 and 60cm models as well. He recommended it over the F90 for the Carbon Fork and Tiagra Group. It's worth the extra $250 according to him.

He also has F65 (limited sizes) and Roubaix with 105 Compo Group $1000 (Special because he can't get F70 until August) or if I decide on steel a Roubaix Pro (853) up-fitted with Triple for $1250.

He also offered to do a Fit-Kit + some additional personal observations of me while riding various bikes for $50 refundable against anything I bought in his shop whether I ended up getting the bike there or not. He recommended I NOT spend over $1000 (Unless I must have steel and 105) for a first bike until I had enough time under my belt to make a informed decision. All of this was on a weekday. I went in on saturday afternoon and decided this was not a good day for the Fit-Kit (I didn't ask) as he and his three employees were trying to get some bikes out of the shop + three new bikes together for pick-up and waiting on a whole herd of customers. Plus one guy from out of town who came in and bought a bike 2 hours from closing (Still in Crate) and they agreed to stay over to get his bike ready for pick-up.

His prices seem good, his attitude is excellent, and he appears to have the best interest of the customer at heart. Sound like a good LBS?

"Aluminum last much longer than steel because it has a much higher fatigue limit" - the old Steel vrs Aluminum argument. This is one better left untouched.

1. Is there a certain optimum length stem for a certain frame? according to Eddy Merckx, if a frame fits you perfect, you'll need a 110mm stem. With that being said, somewhere between 100 and 120 is pretty safe and shouldn't affect handling adversely. There are always exceptions and this is just one mans opinion / experience (as all my comments below are).

2. What are the drawbacks to say a 55cm TTL + Long 140mm stem vs 60cm TTL + Short 90mm stem? you may not be able to get your bars high enough to be comfortable as smaller frames have a much shorter head-tube than the same frame in a larger size. You may also experience unnecessary toe overlap with the front wheel depending on how small you go. I personally have ridden frames that were too small and could never get comfortable.

3. Should I just look for a frame that would end up the correct length with a 120-130mm stem? Yes, a frame that fits is the only way to start! My advice as you're a newbie - buy a bike that feels comfortable with between a 100 and 110mm stem after everything is adjusted to fit you. After riding the bike for a while and getting comfortable with the position on a road bike, you WILL gain more flexibility. With that added flexibility you may want a more stretched out position than you first started with. Starting with a shorter stem will allow you to extend your position without adversely affecting the handling. You also will most likely want to start out with the bars not too far below the saddle (1-2 inches). That's not a bad thing as long as you can remove spacers from under the stem (or flip the stem) as you gain more flexible if you ever decide you want a more aggressive position.

Even seasoned riders (who live in northern states) may start out with a less aggressive position on the bike in the spring. You just never will have that end of season flexibility 1st thing in the spring.

4. During test rides how do I tell the difference between a frame that just isn't going to work for me vs bad set-up? Very difficult without (even with) lots of saddle hours on a proper set-up. The good thing is, you've chosen a shop that is offernig to size you with a fit-kit. That will be your best starting point and you can make minor adjustments from there as you log more miles.


Your measurements you gave are fairly similar to mine (although other proportions could be very different) and the sizes he's recommending sound pretty close to what I use. With that being said, getting the fit-kit done should be the first thing you do. It also sounds like the owner is more than willing to work with you and that's a very good thing. In any event, it sounds as if you're on the right track!

For reference my inseam is 89.5cm and my height is 185cm. I ride a 575mm TT (standard 73degree seat tube angle) and use a 120mm stem and run 3.75-4 inches of drop from the top of the bars to the top of the seat. In the spring I pull off the 120 stem and swap it out for a 110mm for around the first 750 to 1000 miles until I regain my flexibility (seems to take longer every year).

Good Luck

Do the Fit Kit. It's an excellent starting point. Also get the Rotational adjustment for your cleats if they have that adaptor.

Gene: Seems like you've found a good shop to deal with. Make an appointment to get the fit kit done. This allows the shop to bring in an additional employee, if needed. When you are finished you'll have all sorts of measurements that you or the shop can use to adjust the bike so that it fits you properly.

Good Luck!

Zack

The only guide to TT/stem-length combos I have seen is by Tony Oliver in his book "Touring Bikes". The data is applicable to touring and most road bikes.
The table quotes TT in inches and stem length in cm, so you will have to convert.
The range of quoted TT varies from 20.0" to 23.4 and the stem varies from 60 at the low end to 110, varying proportionately. I can type out the whole table if you like.
The modern style may be for longer stems, and steering geometry may have compensated for the difference in sensitivty that longer stems give.

As far as Al having a greater fatigue limit than steel, we have a couple of engineers on here who can refute that piece of misinformation with greater authority than myself.

Al has no fatigue limit, it just cracks and fails.

I know aluminum has no fatigue limit. The point is, I believe the shop in question knew it and said the exact opposite.

Try and look at side profiles of pro riders (this is of course you are morphologically 'normal' - then again who is?) in the racing tuck. See where their knees come into alignment with the inside of their elbows. Its as good a place to start. Then compare it to the fitkit.

"During test rides how do I tell the difference between a frame that just isn't going to work for me vs bad set-up?" Given that you are new to cycling it is more likely that you will ride into any set-up you work out to be the ideal. What is 'comfortable' may not be the most efficient. In that case first impressions are your only guide. I can't see any problems later on changing saddle height and fore/aft, and stem length. fine tuning can go on for years, just look at E. Merckx.

Not only does your LBS sound as if it is 'cool' but you sound like the sorta customer they will come to love. And i mean that sincerely. Cool bike shops love their regulars. I most definitely did.