Is 25.8 pounds heavy for a big guy road bike?

[mike vanderbike]

My current ride is a Kona Zing deluxe (Aluminum frame). I have really enjoyed this bike but it is a little small for me. I am going to pull the trigger in the spring and get the KHS 747 flight steel road bike. (the one designed by Lenard Zinn). I have never let the weight of my bike be a factor in my riding or the components I buy. My current bike weighs 21 pounds. The KHS 747 is nearly 5 lbs heavier (25.8 lbs). For a 6 foot 7, 245 lb rider, does 5 lbs make much difference? In the world where riders are counting grams, five pounds seems like a lot. Any thoughts?

 

[alfeng]

[COLOR= rgb(24, 24, 24)]FWIW. [/COLOR]STEEL is comparatively heavy ... about 3x more than a comparable **** of aluminum according to some ...

[COLOR= rgb(24, 24, 24)]My observation is that a CroMo steel bicycle frame in the 57cm size range will typically weigh about 2 lbs. more than a [/COLOR][COLOR= rgb(24, 24, 24)]comparable[/COLOR][COLOR= rgb(24, 24, 24)] (in design & size) aluminum bicycle frame ... [/COLOR]

[COLOR= rgb(24, 24, 24)]So, it doesn't surprise me that a significantly larger steel frame might not weigh 4+ [/COLOR]lbs. more than the slightly smaller sized alloy frame of your current bike ...

[COLOR= rgb(24, 24, 24)]Due to possible "engineering" of the tubes for the larger size frame, the downtube may be more robust than on smaller frame and consequently the larger frame may be slightly heavier than if one were simply to presume a proportional adjustment in size & weight ...[/COLOR]

The bottom line is that if the wheels on your new bike + other components are comparable (or, better), then the weight difference will probably not be noticeable ...

BTW. For a variety of reasons, I recommend that you choose Campagnolo shifters ... it's not just a cosmetic recommendation (i.e., many people bought Shimano AND Trek because that's what Lance used ... later, they bought SRAM because THOSE were the shifters found on subsequent winning bikes of the TdF/etc.) ... not that there is anything wrong with choosing components based on cosmetics!

Regardless, if you look at Zinn's ads, the bikes more-frequently-than-not usually have Campagnolo shifters ... whether that is a subliminal suggestion or if there's another reason ... well, who knows? Product placement is not an impossibility.

Also, this may be stating the obvious, but at your height, you probably want cranks which are 180mm long OR longer (ask Zinn what length crankarm he prefers to use OR recommends). The slightly longer crankarms will add a couple of ounces.

If you are getting 46mm handlebars (which you should probably consider at your height), that may add a couple of ounces ...

• 46mm is the widest size, AFAIK ... maybe, there are wider bars
• handlebars are NOT "created equal" -- on many, where the brake levers are mounted will be slightly narrower than the ends ... the TruVativ Rouleur TEAM handlebars (do they still make them?) are as wide where the brake levers are mounted as at the ends ...

Another consideration would be to contact Richard Schwinn at GUNNAR and see if he can cobble together a frame for you in a comparable size to the KHS 747 which you are considering ... and then, simply transfer the bulk of your existing components OR build it up with other parts ...

• Gunnar frames are the non-custom baby-brother to Waterford frames

A custom frame may be worth considering ... or, minimally, contacting the builders to see what they might recommend as far as frame dimensions ... different builders may (actually, probably OR will) have slightly different ideas as to what they would build for you.

I don't know what the KHS 747 costs ... if you are on a "tight" budget, then a consideration would be to select an XL size 29er Hardtail frame & mount a Rigid fork ... the XL 29er will probably have as long a virtual top tube (I would think at least 64cm) as whatever Road frame you are looking at ... probably longer.

If you are moderately flexible AND use a Road fork, then that will lower the front end & in so doing make the effective top tube be at a shallower angle & therefore a cm-or-two longer ... a trade-off, but the head tube angle will probably be at about 72º or 73º -- the norm for most smaller Road bikes.

• a high-rise stem can partially-or-completely offset the difference in effective stem height
• a shorter stem has the same net effect as having a longer stem which is mounted with fewer spacers

A Touring-or-Tandem fork will result in an intermediate top tube length (from a 'true' 29er setup with a suspension-corrected Rigid fork & a Road fork which uses a normal 39-49 reach Road brake) & intermediate head tube angle.

 

[mike vanderbike]

Thanks for the good info. FYI: The 747 bike does have a 46 cm handlebars and a 200mm crankset.

 

[alfeng]

BTW. A steel fork typically weighs a pound more than a Carbon Fiber fork ...

The KHS 747 Flite's steel fork's l-o-n-g-e-r steel steerer probably adds another half-pound-or-more than a shorter steerer would have ...

• the fork on the 747 Flight looks a little more stout than a traditional steel for, so that could account for a few additional ounces.

So, if your Kona Zing happened to have a carbon fiber fork, then that is potentially another pound-and-a-half difference between the weight of the two bikes.

A smaller steel frame would probably have a 31.8mm Down Tube + a Top Tube whose diameter would be the same size as the Seat Tube's diameter, so the specs which I saw suggest that tubes on the 747 Flite are indeed over-sized & more robust than the tubes on a smaller steel framed bike.

---

FWIW. I belatedly looked at info on the KHS 747 Flite, and it is very, VERY NICE ...

• [COLOR= rgb(24, 24, 24)]to suggest that it is a [/COLOR]very good[COLOR= rgb(24, 24, 24)] deal is an understatement, IMO, because the frame IS really the equivalent of a semi-custom frame which would cost at least $600, alone ... if not $1600+ ... some custom frames cost even more![/COLOR]
• [COLOR= rgb(24, 24, 24)]the inclusion of 200mm cranks just makes the deal all the sweeter[/COLOR]

The Tektro brakes are good ...

• some people don't like the "stock" brake pads, but those can always be changed.

The Formula hubs are good, too ...

• FWIW. I rate them just below the upper echelon of hubs based on the Formula hubs that I have.

The only (?) obvious thing which I think might have made the design better would be if BOTH the frame AND fork were capable of handling slightly larger 700x32 tires ...

• and, it IS POSSIBLE that the frame & fork can accommodate 700x32 tires, but there is no indication which I came across
• fender mounting eyelets aren't very sporty (if the dropouts aren't chrome plated then unwanted eyelets can always be filed off by the end-user), but they would have been nice (IMO) since they would have given the rider that option without resorting to only clip-on fenders
• I'm NOT sure why the effective Top Tube length is only 62cm, but that is probably the length which Zinn has decided works well for him + his taller clients

The Reynolds 520 tubing is a little heavier than some of the more exotic steel tubing options, but it rides well.

So, even though 'I' prefer Campagnolo shifters, I would say that the KHS 747 Flite is very nicely spec'd & well priced ...

• Campagnolo shifters can be mated to Shimano drivetrains, BTW!!

 

[David Gerchman]

um my all steel Specialized allez weighs 20.81 lbs It will be about 2 lbs lighter when I get my new wheels and a turbo pro on the rear. I am going up hills easier and easier, I cant tell if I am getting stronger or lighter lol-David

 

[danfoz]

Originally Posted by mike vanderbike .

The KHS 747 is nearly 5 lbs heavier (25.8 lbs). For a 6 foot 7, 245 lb rider, does 5 lbs make much difference? In the world where riders are counting grams, five pounds seems like a lot. Any thoughts?

5lbs is a whole bunch but may not be that notceable on the flats once you are rolling , 25lbs is the weight of the bike I rode to 2nd place in the 1982 Bear Mountain Hill Climb (top end steel at the time was 19.5-21lbs). Velo News did a test a couple years back (how "scientific" I have no idea), but dropping 3lbs (or something similar) equated to less than a 10 second gain over a flat 25 miles. The mountains would be a slightly different story. Think about putting a 5lb dumbell in a napsack and trucking that along.

Bikes are way lighter today, but heavier bikes can still rock the road!
(my point above was not to brag, after all I was the first place loser, it was just to say sometimes weight is overarrated)

 

[alienator]

It's dead simple to find out what effect weight has on speed on a road with a given grade (as in incline). Go to Analytic Cycling to play with such numbers and get real answers as opposed to seat of the pants imaginings. For example, a 200lb rider/bike combo going up an 8% slope, with the rider putting out 250W, will go 7.31 mph. A 195lb bike/rider combo on the same hill putting out the same power will romp to an earth shattering 7.49mph. Wow! That 2lb reduction in wheel weight? It'll do even less. Wheels on climbs rotate much slower than on the flats. Why is that important? Well, everyone that's read bike magazine has been told of the magical properties of a wheel's moment of inertia. Of course, when you actually learn what impacts the torque needed to accelerate, you find that:

1. A bicycle whee's moment of inertia is pretty small to begin with.
2. MOI only has a linear effect on wheel acceleration. Cut a wheel's MOI by 20%, and the torque to accelerate the wheel, all else being equal, decreases by 20%.
3. Wheel acceleration increases with the square of the wheel's angular frequency (number of degrees it rotates per second) and its RPM. Reduce the RPM by 20%, and the torque to accelerate the wheel drops 36%......but but the wheel is turning around more slowly.

Aero benefits from wheels actually dominate on climbs until the speed gets very slow/the grade gets steep. When the grade does get steep, it's overall bike/rider weight that is the big influence, not a wheel's MOI. The best solution is to take 5lbs off the corpus since not only is that a 5lb loss, it's also something that typically results in slightly better conditioning and better human performance. Learning about this stuff in bike magazines is like learning about quantum physics by reading Reader's Digest. A great number of magazine journos have no clue about the actual science that defines the performance at hand. Magazine journos are most often scientifically illiterate just like much of the American populace.

 

[mike vanderbike]

Thanks alienator. You provided a varietal cornucopia of information. 5-pounds off the corpus is the most cost effective solution. Plus I could stand to be 5 lbs lighter.

 

[alienator]

Thanks alienator. You provided a varietal cornucopia of information. 5-pounds off the corpus is the most cost effective solution. Plus I could stand to be 5 lbs lighter.

Add to that the most important aspect about a bicycle its fit, its ride, and the rider's satisfaction with the bike.

 

[typevii]

Maybe too late to add to this thread, but as a KHS 747 owner maybe I can add a little. Out the box the 747 is heavy but it is built strong. Depending on your needs you can easily loose a few pounds from the overall weight (if you want to, this bike is built to handle big and heavy riders, so not everyone will want to start swapping in lightweight parts). The forks and wheels are easy, and there are good lighter and strong parts available (wheels, ksyrium elites I hear are good I use Campag Zondas. Forks, Enve 2.0). Not necessarily cheap, but readily available. After that, the usual seat post, saddle, bars etc can trim off a little more. At then end of the day this will never be a 15lb bicycle. It is a big, strong steel frame, and those 200mm cranks, whilst awesome, must weigh a fair amount. Anyway I wouldn't swap them, they were the main reason I went with the KHS747. Mine is about 20lbs with pedals and bottle cages now. I'm about 200lbs in riding gear (tall but not really heavy). Oh and even with what have done to mine I figure it has still cost me half the amount of a custom built bicycle of similar weight and spec. Fits me and rides very well.

 

[Clancy]

i don't know the answer to the posted question