Commuting - Ways to increase my avg speed?

For background, I started commuting about 2-3 months ago. My commute is about 10 miles, mostly flat but a few small hills, a lot of narrow two-lane semi-country roads (it's a former rural area that is turning suburban). My bike is a Haro Express Sport with stock tires.

I'm a pretty slow 11 MPH average right now. Although my main philosophy behind bike commuting is that slow bike commuting is better than no bike commuting, I think I'd really like to increase my average MPH, in order to A) help increase my fitness, maybe get a little faster so that I can go riding with other people and not be the slowest one in the pack, and B) reduce my ride time so I can sleep in a little longer. :)

Do you have any suggestions for increasing my speed? I'd prefer not to buy another bike but am open to modifications on my current one.

First thing to check is your seat height. Is it adjusted for optimum efficiency? You get more power transfer if it is set up at the right height.

Speed comes with effort and time in the saddle. There are no shortcuts.

Get a motor with a better power/weight ratio.

Speed comes with effort and time in the saddle. There are no shortcuts.

+1

I don't know what fitness level you're currently at, but after only 2-3 months, that doesn't sound too bad. You'll get faster with time if you want to.

These folks speak the truth..Proper fit and maybe some slicks if your running knobby tires and Ride hard !!

http://www.sheldonbrown.com/saddles.html (scroll down to "height" adjustment)

If you like pain look up "Base miles" and then "Intervals"

http://www.bicycling.com/training-nutrition/training-fitness

Im not sure how much more speed it will actually gain you but as cfxmarauder said, change your tires out to something thinner and smoother than the .45's on there now. this will allow you to run at a higher tire pressure which will reduce the rolling resistance (and noise). the other way to increase speed (besides pedaling harder/faster) would be to change your gearing, although 14 -28 isnt that far off. Perhaps you could find some larger chainrings that fit your crank spacing.

Take days off when your legs are tired. Your fitness improves on the days you rest.

You might also want to consider a bike computer with a cadence feature and make sure your shifting technique is good.

http://sheldonbrown.com/gears.html

Beyond that, ride more.

You get faster by riding faster. ;)

Seriously, you have to get your body to adjust to a faster pace. To help that process, you can do "intervals". Here's some tips (http://www.cptips.com/intervl.htm).

There's a lot of mumbo jumbo in there. To simplify it, go the section where they talk about telephone poles. The idea is to go really hard between two telephone poles, then go at a more relaxed (but not turtle slow) pace for the next 3 or 4 poles. Do several of these during a given ride, then don't do it again for the next ride or two. You only need a couple of these sessions a week and you need to have adequate recovery time between them.

Also make sure you warm up a good 15 to 20 minutes before you start them.

Clipless pedals helped me speed up a little. You can spin faster, smoother and more efficiently with foot retention.

If running platforms sans clips ATM, then just getting some clips and straps on there should net almost 2 mph avg, at least it did for me. Should be about the same for other foot retention methods.

When I had a long flat commute (17.5 miles each way in PHX, AZ) clip-on aero bars got me about 1.5 mph avg.

Otherwise, practice makes practice.

Oooh, just looked at your bike, Haro Express Sport.

http://www.harobikes.com/mtb/images/bikes/med/B941A1287078981.jpg

A -17° non-adjustable stem, some flat bars with barends and a more svelte saddle should help a bit. See if you can get your saddle height high enough with the stock seatpost - with the heel of your shoe on the pedal in the position in the pic your leg should be straight (no bend in the knee). Make sure the tip of your saddle's not more than 6cm behind the bottom bracket centerline after that.

You're gonna want your bars to be about level with your seat if not lower.

Luckily the Seattube is not super laid back and the seatpost isn't suspension...

The biggest thing you can do is get higher pressure tires. I'm running 700 X 32 at 110ibs. I wouldn't worry about clipless pedals or aero bars or any other equipment change until you got tires good for atleast 95 ibs pressure. You'll enjoy your ride more especially after pushing fat tires around. After you get the tires then just pedal faster in a higher gear.

Hmmm. I'd get my bars to just about an inch above the top of the headtube 1st. Then a non-fat saddle. Then tires.

But I guess we all have different priorities.

Actually I might do the saddle first. Tough call there.

"It never gets any easier - you just go faster." - Greg LeMond

don't get discouraged by that, you're not competing.... but there are no shortcuts (and often detours) on the way to improving fitness.

read up on performance training and see what makes sense and works for you. as mentioned, things like tires, saddle height, etc will have an influence on speed but beyond that, the faster you try to ride, the faster you'll wind up riding - it just takes time. i've been riding a commuter for a while and when i first got my tt/tri bike i was scared by how fast it wanted to go without too much effort (it's still kinda scary) but some bikes are made for speed more than others.

if your roads are smooth you'll benefit from a higher PSI... if you roads are not smooth, you'll likely benefit from a lower PSI. hard tires on bumpy roads redirect the energy of the bumps up, while softer tires absorb some shock and keep you rolling forward.

"A relaxed seat angle combined with a taller head tube makes this one comfortable hybrid! We engineered the Express to be easy on your back by putting you in a more upright riding position." - it looks like that bikes is designed for comfort but not for speed (almost like a beach cruiser). spend some time on it, try making some adjustments, and if you get frustrated try out something that's more of a "commuter" bike. if you don't have any plans for panniers, maybe even a "road" bike. the different geometries will make a big difference. for now, enjoy the ride, enjoy the exercise, keep your cadence high.

Nothing wrong with 11mph average commuting speed. Why strive to go faster on a commute? You might save 3-5 minutes if you push harder. I really see no problem with 11mph average. Your bike is not built for speed either, and there is nothing wrong with that as well. I would not spend much money on that bike. If the slowness really bothers you get another bike with more aggressive geometry.

Not that much need for more aggressive geo. The seattube angle on that thing isn't overly slack to my eyes. Head tube is REALLY high though. Just gotta get the saddle height and bar height close and vroom!

Could require long seatpost in addition to a new stem.

As others said, better speed will come with increased fitness. As far as your bike goes, switching to some lighter, narrower tires with a smooth tread will probably increase speed more than anything. You didn't mention how much gear you are carrying. However, if you have your bike loaded down with panniers and all sorts of gear that isn't essential, that will really slow you down. Anything you can do to lower your total weight will help increase speed.

As others said, better speed will come with increased fitness. As far as your bike goes, switching to some lighter, narrower tires with a smooth tread will probably increase speed more than anything. You didn't mention how much gear you are carrying. However, if you have your bike loaded down with panniers and all sorts of gear that isn't essential, that will really slow you down. Anything you can do to lower your total weight will help increase speed.

For what its worth, I ride a heavy cargo bike loaded with close to 30lbs of extra stuff daily, I consistently have 13MPH averages, and I have just started. Not really a flat commute either. I think this guys dilemma comes down to practice, pedaling method, and basically gaining experience.

I agree with the others: Why rush? You are going to work, not all that exciting :) I love the days where I just take it easy, kick back, and enjoy my surroundings. Even when I really kick it up and nail a 15-17MPH average I only cut about 4 minutes off my time.

Anything you can do to lower your total weight will help increase speed.
i've wondered about this... will it really increase speed or just acceleration?

now if only i could find a pannier rack for my tt/tri bike...

There are a number of good articles on increasing speed scattered across many websites and publications, but the advice boils down to several common themes. Keep your head low and your back flat, strengthen your legs so that you can tend toward the higher gears, and train for speed. I'd also recommend doing some club rides. Try to keep up with the stronger cyclists. You'll probably get dropped pretty quickly at first, but over time your speed will increase. When I'm trying to build speed I also treat the space between traffic lights as a short time trial, racing from light to light.

I can feel the difference when I have 2 full water bottles and a full seatbag on my road bike. That's gotta be a good 12 pounds, though. There's no cheap/easy way to shave 12 lbs offa the bike in question.

i've wondered about this... will it really increase speed or just acceleration?

now if only i could find a pannier rack for my tt/tri bike...

Both. Think about the extra work it takes to maintain speed up a hill carrying extra weight. As for pannier rack you could probably find one of those cantilevered gizmos. I have one on a fixed gear track bike. They don't support an enormous amount of weight, but I can carry a change of clothes and my lunch.

Both. Think about the extra work it takes to maintain speed up a hill carrying extra weight. As for pannier rack you could probably find one of those cantilevered gizmos. I have one on a fixed gear track bike. They don't support an enormous amount of weight, but I can carry a change of clothes and my lunch.
makes sense uphill... downhill or level i'd think it's closer to a non-issue. what affects me more than weight, even on hills, is wellington's wind. my panniers are like sails... there are times i have to pedal downhill and other times when i can almost coast uphill.

link for the cantilevered gizmo rack?

Nothing wrong with 11mph average commuting speed. Why strive to go faster on a commute? You might save 3-5 minutes if you push harder. I really see no problem with 11mph average. Your bike is not built for speed either, and there is nothing wrong with that as well. I would not spend much money on that bike. If the slowness really bothers you get another bike with more aggressive geometry.

+1

Even though I was the one that posted information about "intervals", I have to agree.

The big question is what do you want your commute to be like? If you want it to be a workout, then you definitely can add a few mph to your average, - if your commute isn't filled with intersections you have to slow down and/or stop at.

If you have a ton of intersections to deal with, that's going to keep your average speed down and there's not much you can do about it.

After looking at your bike (and it is a nice bike), I have to say that 11 mph average is about right for what you have. It puts you in a very upright position which a lot of people like. It's not intended for going fast though and I personally think that swapping out stems and bars may not accomplish much other than making you more uncomfortable.

Finally, figure out how much sooner averaging a few extra mph would get you to work. It may not be worth it.

+1 fitness and correct bike fit will be the primary factors in your average speed. The bike itself is probably a slight factor - very upright seating position, big saddle - it's more of a "cruise through the neighborhood to buy flowers" type of a bike than one for a 10 mile hilly commute. That said, it will do just fine for you to continue to build your fitness.
Start putting away some money, keep riding the Haro, then when you have $1000 or so saved up we can talk options.

Start out with 2 days a week (Tues, Thurs)of increased effort - really push it on the hills (to the point of being out of breath - near maximum effort), gather yourself on the flats for a minute or two, then pick up the pace again. On the alternating days (the other 3), go a bit easier and don't worry about pace. Your legs should be a bit sore, and riding easier helps them recover. Some studies show that an "easy" ride is more beneficial than a total "off" day. Go with what feels right to you.

After a few weeks, switch so you are doing M-W-F as hard days and Tues-Thurs as recovery days. After several more weeks you should be feeling noticeably stronger.

Diet can also help with this. Make sure you give your body the protein it needs within 15-30 minutes of your rides and get enough sleep.

Now is the time to develop some good form. Spin, don't mash. Maintain an absolute minimum pedal cadence of 60 RPM, preferably closer to 90 RPM. Pedal with the balls of your feet over the pedal spindle (axle), not on your heels. Ensure your saddle is adjusted to the correct height.

Good luck!!!!!!! :thumb:

+1

Even though I was the one that posted information about "intervals", I have to agree.

The big question is what do you want your commute to be like? If you want it to be a workout, then you definitely can add a few mph to your average, - if your commute isn't filled with intersections you have to slow down and/or stop at.

If you have a ton of intersections to deal with, that's going to keep your average speed down and there's not much you can do about it.

After looking at your bike (and it is a nice bike), I have to say that 11 mph average is about right for what you have. It puts you in a very upright position which a lot of people like. It's not intended for going fast though and I personally think that swapping out stems and bars may not accomplish much other than making you more uncomfortable.

Finally, figure out how much sooner averaging a few extra mph would get you to work. It may not be worth it.

I also agree with all of this.
Despite my "training" related post earlier, bear in mind that 11mph is respectable, especially on that Haro, and considering the "real world" aspects of stop signs, traffic lights, etc.
I think the key is to listen to your body. Improving fitness and strength will require some discomfort, but don't overdo it.

I would change my mindset from trying to increase my average speed to simply getting stronger.
The easiest way to get stronger are intervals followed by a low intensity day or a rest day.
Plus, racing to work is counterproductive. :p

+1 fitness and correct bike fit will be the primary factors in your average speed. The bike itself is probably a slight factor - very upright seating position, big saddle - it's more of a "cruise through the neighborhood to buy flowers" type of a bike than one for a 10 mile hilly commute. That said, it will do just fine for you to continue to build your fitness.
i'm not sure i'd agree with that. on my commuter, 40k/h downhill (maybe faster if it's a big hill) is pretty fast. very soon after getting used to aero-bars and clipless pedals on my tt/tri bike i could hit 40k/h on the flats, without going "all out" - i was scared to go any faster. i'd say the bike (geometry, aerodynamics, tires, weight, etc) all add up and make a huge difference. i'm still amazed at the speed difference between the two bikes.

as has been pointed out, the OP's bike just isn't built for speed... but i'll agree that it should be fine for building up fitness.

use it if ya got it. that bike isn't made for winning races, it's made for enjoying the ride... use it for that. if/when the OP decides to upgrade to something faster, s/he'll have gained some fitness and experience to help make the right choice about which bike to get next.

i'm not sure i'd agree with that. on my commuter, 40k/h downhill (maybe faster if it's a big hill) is pretty fast. very soon after getting used to aero-bars and clipless pedals on my tt/tri bike i could hit 40k/h on the flats, without going "all out" - i was scared to go any faster. i'd say the bike (geometry, aerodynamics, tires, weight, etc) all add up and make a huge difference. i'm still amazed at the speed difference between the two bikes.

as has been pointed out, the OP's bike just isn't built for speed... but i'll agree that it should be fine for building up fitness.

use it if ya got it. that bike isn't made for winning races, it's made for enjoying the ride... use it for that. if/when the OP decides to upgrade to something faster, s/he'll have gained some fitness and experience to help make the right choice about which bike to get next.

This winter I was on a group ride that turned into more of an expedition.

Since this was winter most of the people weren't riding straight up road bikes. Typically the bikes were outfitted with one studded tire. I had two, - which made it a long and hard day for me. Anyway, one of the guys was riding an old cruiser with a geometry similar to the OP's bike. When I first saw it, I thought to myself that this is going to be a slow ride, - which given my tires suited me just fine.

I quickly found out thought that this guy on his cruiser (with no studs) had no problem keeping pace. Every once in a while the ride leader would offer a Cliff bar to the first guy to reach some landmark about 1/4 mile off. A few times the guy on the cruiser gamely tried to stay with the lead pack. As strong as he was he just couldn't do it. So while his average speed was pretty decent, it's just too hard to get a cruiser really moving and maintain that pace.

That matches my own experience with different types of bikes. The average speed on my commute isn't all that much different no matter which bike I choose, but the top speed can vary quite a bit.

That's a respectable speed on what is a "comfort bike". You'll get faster the longer you ride. 20 miles a day will get you fit fairly quickly. Watch your diet, drop some weight, and you'll increase your power to weight ratio. Then buy a road bike. :-)

You're gonna want your bars to be about level with your seat if not lower.

Here, I think, we arrive at the crux of the matter. That bike is designed for a comfortable, relaxed ride -- not speed. The rule of thumb that says you want your bars at seat level or below assumes a bike more or less designed for speed. The geometry of the OP's bike (http://www.harobikes.com/mtb/manual/2011HaroAdultGeometry.pdf) does not allow for such a setup. The top tube length on the medium size is 548mm. That's about the same as on my CX bike, so with drop bars and a 90mm stem or so, the low bars/high seat might work. With flat (even slightly swept back) bars, the fit just isn't going to work.

There's simply no way around the fact that you're going to have an upright riding position with that bike. Even so, it's a decent enough platform for building fitness as a new rider. I actually like the spec for an entry-level commuter/recreational bike. An average speed of 14-15 mph should be achieveable over time.

I'd say the biggest bang for the buck improvement to the bike would be 700x32 slicks, which would yield immediate improvements in efficiency, then a new crankset (and maybe new freewheel) once you have enough fitness that the 42x14 top gear becomes a limiter.

I would concentrate on going uphill faster. That is where you can make the biggest gains...uphills can suck the life out of your cadence very quickly if you don't concentrate on them. Think about it...Also, consider getting a bike computer with the little arrow that indicates whether you are above or below your average...That really helped me when I wanted to decrease my commute times.

+1 again...

I switched from a hybrid to a road bike and my average speed went from around 12 (it's not as relaxed a geometry as the OP's) to around 14 or so. My commute time really hasn't changed. Whether or not I catch a light at an intersection has a bigger impact on my commute time than how fast I ride unless I'm basically sprinting the whole way home because I'm late.


+1

Even though I was the one that posted information about "intervals", I have to agree.

The big question is what do you want your commute to be like? If you want it to be a workout, then you definitely can add a few mph to your average, - if your commute isn't filled with intersections you have to slow down and/or stop at.

If you have a ton of intersections to deal with, that's going to keep your average speed down and there's not much you can do about it.

After looking at your bike (and it is a nice bike), I have to say that 11 mph average is about right for what you have. It puts you in a very upright position which a lot of people like. It's not intended for going fast though and I personally think that swapping out stems and bars may not accomplish much other than making you more uncomfortable.

Finally, figure out how much sooner averaging a few extra mph would get you to work. It may not be worth it.

Aside from the obvious (try harder), here are my recommendations, in order from most benefits to least.

1. Convert it to an electric bike (www.bionx.ca, electric-bikes.com, etc..)
2. Change to smooth tires if you're currently using knobby tires
3. Lose weight if you have a few pounds to spare
4. Adjust your bike for a more aerodynamic body position (lower handles)
5. Switch to clipless pedals

I ride an electric bike and my average is about 4-6mph faster and I still get a good workout.

You reach a point, IMO, when trying to go faster, that a bike designed for speed is more comfortable than a bike designed for comfort.

Thanks for all of the replies! I really appreciate the advice and information. I'm getting a general consensus that it's mostly just a matter of keep working, maybe with a little bit of pushing myself thrown in. I'm not necessarily trying to get to work faster or win any races, but I would like to increase my fitness just a little bit (I would like to lose 5-10 pounds). Maybe if I keep this up I can reward myself with a road bike when I hit a year of commuting!

Read Bicycling magazine -- I've not read it in a few years, but they used to have a cheesy article about "50 minute" intervals in every issue.

Also, in general: if you find yourself enjoying any aspect of a bike ride, you're riding garbage miles and not increasing your fitness. Immediately punish yourself with more intervals because you don't hate yourself enough to get better.

Also, in general: if you find yourself enjoying any aspect of a bike ride, you're riding garbage miles and not increasing your fitness. Immediately punish yourself with more intervals because you don't hate yourself enough to get better.

GARBAGE MILES made me laugh

I started commuting about 2-3 months ago...my main philosophy behind bike commuting is that slow bike commuting is better than no bike commuting


Simplest way to improve speed is to just keep at it. You haven't been at it long. When you feel you can, increase the distance you ride. General fitness will improve and speed will follow.

After that, some speed type efforts will help. Ride hard for 2-3 minutes, slow back to recovery speed, then repeat. Or use telephone poles or some other landmark, like tjspiel suggested.

By the way, I like your philosophy.

One often overlooked way to increase average speed is to change the wheel circumference setting on your cycle computer (but don't actually change the wheel size). If you make the wheel circumference setting larger the computer will think you are traveling further for the same period of time and this will increase your average speed. I suggest doing this slowly, increasing by just a millimeter of diameter a week. If not, your increase in speed will increase before you have mastered the bike handling skills needed to safely ride at the higher speeds. This method has the added benefit that it will increase your mileage as well, but again, it is better to slowly increase your mileage instead of all at once.

On the topic of weight and whatnot, My trek soho s weighs in at 22.5 lbs. stock, and I'm able to average 15+ miles per hour on my commute without much issue. It's great exercise to ride a single speed as you have to peddle faster to go faster, and the low weight and lack of drivetrain resistance allow me to climb any hills that I encounter. It sounds like your commute is similar to mine, so I would recommend a single speed as a commuter for you. Check out the gary fisher gritty, I believe it's chromoly and has a nice easy gearing 38x17? Perfect for a starter who wants to get into shape. Oh yeah, I just started last spring, and I can agree with all the other people that said just ride more. Something I did as well was, I found a nice loop that was the same length as my commute one way, and on my days off rode as hard as I could on that route. It was a combination of hills, flats, nice country, and mup. I think that definitely improved my trip time to work, as I got used to killing it for that amount of distance. I didn't care so much about how long it took me to get home. There's no time clock to beat there ;).

Nothing wrong with 11mph average commuting speed. Why strive to go faster on a commute? You might save 3-5 minutes if you push harder. I really see no problem with 11mph average. Your bike is not built for speed either, and there is nothing wrong with that as well. I would not spend much money on that bike. If the slowness really bothers you get another bike with more aggressive geometry.

+1 on this. My commute is 7.5 miles with lots of traffic and lights. Sure, I can really push it and arrive completely winded, only to find out that I have saved less than 5 minutes.

One often overlooked way to increase average speed is to change the wheel circumference setting on your cycle computer (but don't actually change the wheel size). If you make the wheel circumference setting larger the computer will think you are traveling further for the same period of time and this will increase your average speed. I suggest doing this slowly, increasing by just a millimeter of diameter a week. If not, your increase in speed will increase before you have mastered the bike handling skills needed to safely ride at the higher speeds. This method has the added benefit that it will increase your mileage as well, but again, it is better to slowly increase your mileage instead of all at once.

Hey! Why'd you reveal the secret to my 25mph overall average speed?

Minimize aero dynamic drag , low body profile, no flapping clothing..

Bike in #11, is too upright to make a big gain in speed,
then don't worry about fast, just ride Safe.

get a road bike w/ drop bars

Hey rumrunn6: I like you signature, except replace the "it doesn't take much....." part with "only 6 or 7 people are watching it at any given moment".

OP -- I started commuting with the same type of bike (Giant Cypress) and it took me 1:20 to do a 13 mile commute. now I have it down to 50 minutes, and I even did it in 45:30 on a Saturday morning. so, in addition to the tips above which are germane to any riding, let me give you some commuting-specific tips:

* ride off-peak. more traffic on the road slows you down: motorists, cyclists, and pedestrians. you may get stuck behind cars at an intersection. slow cyclists can block you on a narrow bridge or bike lane. pedestrians can do the same. if you go during rush hour, you are pretty much dooming yourself to a reduced speed. either get up early or just wait until the traffic is gone.

* prep the night before. although it doesn't directly contribute to your mph readout, time spent getting ready in the morning is part of your commute. wipe the chain, top off the air in the tires, mount your bag and fill your water bottles. it's easy to chew up 5-10m in the morning, which is more than you'll save by riding faster.

* proceed through red lights when safe to do so. I used to stop dutifully for every red light, even when there was no traffic around. ceasing that practice probably saves me 5-10m each way. my rules of thumb for when to go on through:
1. no visible cross traffic either direction - including when sensor doesn't notice you
2. 3-way intersection with no visible cross traffic from my side
3. 3-way intersection where there is no outlet on my side
4. walk signs are on in the direction I'm going
5. left turn indicators are on, but there is no one turning left from the other direction

good luck!

One often overlooked way to increase average speed is to change the wheel circumference setting on your cycle computer (but don't actually change the wheel size). If you make the wheel circumference setting larger the computer will think you are traveling further for the same period of time and this will increase your average speed. I suggest doing this slowly, increasing by just a millimeter of diameter a week. If not, your increase in speed will increase before you have mastered the bike handling skills needed to safely ride at the higher speeds. This method has the added benefit that it will increase your mileage as well, but again, it is better to slowly increase your mileage instead of all at once.
Thank you, this made me laugh.

On a serious note, I have the same problem - average speed is still pretty slow. I'm getting about 13mph average over my 15 or 20 mile commute (different route there/back due to traffic). One think I notice is that it's easier to get faster when I get in the drops verses the hoods/bars. I looked at your bike and it's quite upright. Not much you can do about it on that bike, but if you get a new one at some point you may want to look into something that lets you get into a more aerodynamic position. Plus drops are way more comfortable for long rides, they put your hands in a more ergonomic position and you've got ways to switch your grip periodically.

I was in the same place a couple of years ago so I'll chime in here. A lot of experienced cyclists are giving good advice, but you should bear in mind that most of them are approaching it from a much more advanced perspective and may not know or remember what it takes, or may have never been in that position in the first place. Take it all with a grain of salt. Let me say inter alia, that there's absolutely no reason to question your goal. I really can't imagine any real cyclist not wanting to be faster.

I started cycling 3 years ago (car free!) on an old touring bike. I didn't get a speedometer until a year later, with a new bike. I was 48, hadn't exercised in decades, and I can't tell you it was easy. My average speed when I installed a computer was about what yours is.

The most important point I'd make is this: to improve from an average speed of 11mph your top speeds are almost irrelevant. Your cruising speed is what you want to focus on, and your lowest speeds are what affect your average the most. At 11-15mph aerodynamics are not any particular consideration. Therefore, while all the advice about changing positions, changing bikes, outfitting properly and so on is good advice, none of it is going to help achieve your goal. I am confident that you can improve your average speed on your commute with the same bike, in the same configuration, the same accessories that you have now. The only way to improve your average speed is upgrading the engine; and I suspect that's what you're after anyway.

It is correct that high intensity intervals are most effective (and quickest) in increasing your fitness, and presumably speed. It is also the most unpleasant type of exercise and the least likely to be consistently practiced. I know this theoretically from reading studies about cycling and general physiology - I've never tried it. I have a hard time picturing it on your bike, but if you have the 'nads and determination go for it. Simpler, more enjoyable, sure, but slower improvement can be had by leaving it entirely unstructured. Every ride, try to improve on one thing by pushing it. Hit the hills a little harder, concentrate on faster cadence, work on a smoother stroke, push it up a gear for a week or two and when you're almost comfortable, drop it back for a week picking your speed up, shifting up as necessary. But not all at the same time! Just work on one thing, and try to improve something each time. Soon your "normal" gear is one higher (faster), and you can repeat. You can actually enjoy yourself doing it this way, and it does work.

Here, I think, we arrive at the crux of the matter. That bike is designed for a comfortable, relaxed ride -- not speed. The rule of thumb that says you want your bars at seat level or below assumes a bike more or less designed for speed. The geometry of the OP's bike (http://www.harobikes.com/mtb/manual/2011HaroAdultGeometry.pdf) does not allow for such a setup. The top tube length on the medium size is 548mm. That's about the same as on my CX bike, so with drop bars and a 90mm stem or so, the low bars/high seat might work. With flat (even slightly swept back) bars, the fit just isn't going to work.

I reckon one could get a decent position even with the short top tube, just need to get a super long seatpost to get saddle high enough. The bike's ETT is about 23mm shorter than the top tube on my 18" Trek. Barends or trekking bars or long stem all come to mind.