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spinconn 07-28-19 07:17 AM

Frame Geometry And Speed
 
I am back to cycling after a long absence, but this time with an old but fit body. The age has brought me spine issues so I can no longer ride a true road bike.

I tried several types of bikes before buying a Giant Cypress DX. I like it but I want more speed and I only ride on pavement so I changed out the tires to skinny high pressure tires and got a big improvement. But I want more speed if possible, so I rented a road bike for a few days to see what would happen. I got more speed and I loved it, but my spine told me to stop riding that way.

I have been looking at what I can do while still riding in an upright position. I asked my local bike shop if I could just buy a road bike and install a high seat and flat bar and he said no, but didn't care to explain why, so I have been looking on the internet and now I am confused.

Though I used to ride a nice road bike I never did become educated on bike mechanics so I am not fluent in the technical aspects of bikes. However, it seems to me the issue for me comes down to geometry and the frame. So, for this question please disregard biker fitness and ability, pedals, gears, tires, etc. My question is strictly about frames.

1. Is there something about road bike frame geometry that precludes an upright position?

2. Aside from the aerodynamic advantages of a drop bar, does the drop bar position also provide a more efficient cycling position that cannot be duplicated or approached by upright cycling regardless of other aspects of bike configuration?

3. If, as I fear, the answer to the above two questions is in the affirmative, is there a light, stiff, responsive frame out there that would be best for speed and allow an upright position, even if not as fast as a true road bike?

I did not know what forum was appropriate for this so excuse me if this is not the correct one.

unterhausen 07-29-19 04:31 AM

Welcome to the forum. The bike shop owner probably meant that it would be too expensive to switch out all the parts to make a drop bar bike into an upright bike. The other issue is that drop bar frames are usually shorter than upright bikes, so that would make you even more upright.

As far as performance goes, drop bar bikes allow you to recruit the large muscles on your backside. An upright position does not do this as well. As much as I hate to say it, maybe a recumbent makes sense for you.

Kapusta 07-29-19 08:03 AM

While I do not have the allergenic reaction to flat-bar conversions of road bikes that many on this forum do, it makes little sense to buy a drop bar bike knowing up front that you want a flat bar. There is a bit of expense in making the swap.

Answer to #3 : You might look at something like one of Trek’s FX bikes.

BTW, you don’t need to go with super skinny high pressure tires to get speed. There are 32-38mm tires out there that roll just as fast an much more comfortable.

Kapusta 07-29-19 08:43 AM

Answer to #1 :

1. Is there something about road bike frame geometry that precludes an upright position?
Technically...... no. But is is a little more complicated than a yes/no answer.

In terms of the FRAME geometry, frames designed for drop bars are actually MORE upright (shorter reach, higher stack) than ones for flat bars. In other words, the top of the head tube is generally a little taller and a lot shorter reach from the saddle. This is because drop bars put you much farther forward and lower relative to the head tube than with a flat bar.

So, if you put a flat bar on a bike designed for drops, you will in fact have a VERY upright bike. I've done this with an old road bike frame to make an urban commuter that I wanted fairly upright, and it worked great. Now the same frame is a flat bar road bike that my wife loves to ride, and likes the more upright position. However, it did take a bit of fiddling with different stems and bar widths and sweeps to get the handling to feel right. But I go back to what I said in the last post that this is fine if you already have a road bike and like to tinker, but it does not make sense to buy a new road bike just to immediately convert it to flat bar.

Also, not all road bikes have the same geo. Some more "gravel, "All Road" or "Adventure" bikes oriented bikes are a little more upright than road racing bikes.

And finally, there is a lot you can do with different stems and spacers on a bike that has drops.You can shorten the stem (somewhat) and raise the bars on an existing bike pretty easily. It really depends on how "upright" you are looking for.


2. Aside from the aerodynamic advantages of a drop bar, does the drop bar position also provide a more efficient cycling position that cannot be duplicated or approached by upright cycling regardless of other aspects of bike configuration?
Yes. Being bolt upright is not only slower due to aero, but it is harder to utilize the muscles needed to put down a lot of power.

It is worth keeping in mind that a comfort bike like the cypress is just not designed with speed in mind, It is heavy, it has front suspension, and the riding position is bolt upright. Try looking at some flat bar road bikes like the Trek FX series, or if you are looking at Giants, the Escape or Fastroad.

burnthesheep 07-29-19 09:03 AM

Really nice tires, more aero helmet, and well fitting kit can make buckets of difference.

Get some GP5000's and run them TL or with latex, get a modern well vented aero helmet (yes, their venting is better now), and make sure that your kit doesn't flap one bit. Team/race fit.

Those three are probably worth 1mph all together.

livedarklions 07-29-19 11:06 AM

Definitely look at the Trek FX. It's a good compromise between the upright and road bike position. I can get mine into the low mid-20s on the flat, and it climbs great. I don't like it off-road, however.

bruce19 07-29-19 11:51 AM


Originally Posted by Kapusta (Post 21049622)
While I do not have the allergenic reaction to flat-bar conversions of road bikes that many on this forum do, it makes little sense to buy a drop bar bike knowing up front that you want a flat bar. There is a bit of expense in making the swap.

Answer to #3 : You might look at something like one of Trekís FX bikes.

BTW, you donít need to go with super skinny high pressure tires to get speed. There are 32-38mm tires out there that roll just as fast an much more comfortable.

My most recent experience is with Mavic USTs. They are lighter, faster, roll easily and are more comfortable. I am totally sold on them.

spinconn 07-29-19 02:59 PM

Thank you very much guys. This has been an education for me. So many types and makes of bikes today.

Even if it might be faster I doubt I would enjoy a recumbent more than a Hybrid. In retrospect, after reviewing some of the bikes mentioned, and a few more after I got the idea of it all, I could have simply asked what might be the fastest flat bar bike for 2K or less.

Armed with this info I am currently looking at the FX bikes, specifically the 5 though I am not yet ruling out the lower numbered series, the Giant Fastroad bikes, and the Specialized Sirrus bikes.

I realize this encompasses a broad price range but any comments on which of these anyone would prefer would be welcome.

Are there other comparable bikes out there I should look at?

diverbmorrison1 07-29-19 06:02 PM

I too have back issues and Degenerative Disk Disease in the lower neck which prevents me from riding in the rood position. So I took it one step further and ventured into the real of recumbent bikes and I have not look back since. I ride a variety of recumbents such as the low racer the medium racer and a trikes. I like the trike the best when I am tried because I do not need to concentrate balancing the bike, and when I need to stop a hill it is much easier to get started again. In fact If I stop on a hill climb with one of my recumbent bikes I usually need to turn around and go back do the hill because it is impossible to get started again. Just a suggestion that perhaps a recumbent my be easier on your back than even an upright hybrid bike.

Ironfish653 07-29-19 06:02 PM


Originally Posted by spinconn (Post 21050382)
Thank you very much guys. This has been an education for me. So many types and makes of bikes today.

Are there other comparable bikes out there I should look at?

At the risk of further muddying the water, the Cannondale Quick series is another entry in the 'Fitness Bike / Flat-bar Road Bike' category you're looking at.

You're shopping the bike equivalent of a Honda Accord / Toyota Camry / Ford Fusion, except with even less differentiation, since most of the parts like the controls, wheels, and drivetrain all pull from the same suppliers.

Which bike is 'best' for you will really come down to little differences in geometry, or finishing details.

The only way to really know is to go to a bike shop, kick some tires, and take some test rides.

spinconn 07-29-19 06:30 PM

I wish I could take some test rides but the nearest Giant Dealer has no Fastroads, the Specialized dealer has no Sirrus, and the Trek dealer has only the FX 2 and 3. I will check out the Cannondale Quick bikes on line and see if there is one in a LBS to try. I think I will also go take a look at the FX 2 and 3. Thanks.

alcjphil 07-29-19 08:40 PM


Originally Posted by spinconn (Post 21050706)
I wish I could take some test rides but the nearest Giant Dealer has no Fastroads, the Specialized dealer has no Sirrus, and the Trek dealer has only the FX 2 and 3. I will check out the Cannondale Quick bikes on line and see if there is one in a LBS to try. I think I will also go take a look at the FX 2 and 3. Thanks.

Be firm with these dealers. If they don't have the models in stock, they cannot sell you a bike unless you can try them out. Many bike companies have floating stock demo bikes that dealers can access if customers insist. When I worked for a company that distributed a brand of bikes, we kept a stock of demos that we shipped out to dealers so that prospective customers could try out our bikes. Not having a particular model in stock is not an excuse for a dealer to not be able to provide a test ride. Giant, Trek, Cannondale and Specialized are big sellers. All their dealers should be able to access demo bikes. If they can't, look elsewhere

guachi 07-29-19 09:06 PM

My wife has back issues and we got the Trek equivalent of the Cypress - the Verve.

She tried the FX and it was far too aggressive for her. So for you, you might find it a good compromise between the Cypress and a road bike.

If I were to get a second bike, it would be the FX 4, though I see on the Trek website that the FX 5 is $290 off right now.

spinconn 07-30-19 05:15 AM


Originally Posted by guachi (Post 21050911)
My wife has back issues and we got the Trek equivalent of the Cypress - the Verve.

She tried the FX and it was far too aggressive for her. So for you, you might find it a good compromise between the Cypress and a road bike.

If I were to get a second bike, it would be the FX 4, though I see on the Trek website that the FX 5 is $290 off right now.

What are your reasons for preferring th FX 4 over the 5 (other than price)?

katsup 07-30-19 07:31 PM

When you are the Trek shop, ask about the checkpoint. It is Trek's gravel bike, it has drop bars, but more upright than your typical road bike. All manufactures have at least 1 now.

I have heard the 2020 Trek Domane is more upright as well.

guachi 07-30-19 07:51 PM


Originally Posted by spinconn (Post 21051183)
What are your reasons for preferring th FX 4 over the 5 (other than price)?

Same components (IIRC) and the only difference is the carbon frame. It didn't seem worth it to spend $700 more for a carbon frame on a second bike. So the only reason really is price Even as a first bike it doesn't seem worth it.

spinconn 07-30-19 09:03 PM

Thanks, I went to the nearest Specialized dealer and Trek dealer. They had limited bikes in medium frame size so I only got to ride the FX3 at the Trek LBS, and the Sirrus base model at the Specialized LBS. Both were much quicker, lighter and responsive than my Cypress. Both shops are in the city so I did not get to do any distance before having to slow down and stop, not the kind of uninterrupted open road I ride on at home. Still, they were definitely fast compared to my current bike.

I think I liked the Sirrus better by just a little bit. Friday my LBS Giant dealer will get a Roadfast in and I will take it for a test ride also before deciding. Funny thing is the FX and Sirrus, despite having flat bars, were much more aggressive and less upright than my Cypress and this not only made for more efficient pedaling, it felt fine with my back. I am thinking I should also give a drop bar road bike a test but without putting at least a good hour into it I will not know for sure if it would be workable for me. These shops don't want me doing a test ride that far and long.

I will know more on Friday but after these test rides my Cypress is feeling awfully heavy and slow,

Kapusta 07-31-19 07:40 AM


Originally Posted by spinconn (Post 21052732)
Thanks, I went to the nearest Specialized dealer and Trek dealer. They had limited bikes in medium frame size so I only got to ride the FX3 at the Trek LBS, and the Sirrus base model at the Specialized LBS. Both were much quicker, lighter and responsive than my Cypress. Both shops are in the city so I did not get to do any distance before having to slow down and stop, not the kind of uninterrupted open road I ride on at home. Still, they were definitely fast compared to my current bike.

I think I liked the Sirrus better by just a little bit. Friday my LBS Giant dealer will get a Roadfast in and I will take it for a test ride also before deciding. Funny thing is the FX and Sirrus, despite having flat bars, were much more aggressive and less upright than my Cypress and this not only made for more efficient pedaling, it felt fine with my back. I am thinking I should also give a drop bar road bike a test but without putting at least a good hour into it I will not know for sure if it would be workable for me. These shops don't want me doing a test ride that far and long.

I will know more on Friday but after these test rides my Cypress is feeling awfully heavy and slow,

It does not surprise me that the FX and Sirrus are more aggressive than your Cypress. Flats vs drops is only part of it. The frames themselves and the cockpit setups are very different.

This was also a good demonstration that even with a finicky back, you donít have to be super upright to be comfortable.


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