johnbort2

Ok, I can agree with that....lol

rex615

I was secretly rooting for the 920, it is a great looking bike. Best of luck and do post some pics.

asmac

I foolishly posted without reading the entire thread first. Now that I have, I think I'll change it to this ...

Squeezebox

Several people are making serious assumptions about Trek's marketing dept and their engineering dept. And leveling attacks based completely on opinion with zero facts to back them up. Enough already. I've checked out every one of your concerns that you have raised. Looked at all the bicycles you suggested, I rode an LHT. I have gotten as many facts that I could collect. I'm satisfied with it as a good bicycle. I don't want a bicycle that weighs 1/2 as much as it should. Where are their engineers that should be testing their stuff? I called Trek to state your concerns about the 28* wheels. Lower spoke wheels have been getting stronger over the years. Deeper rims, double walled might be part of it, shorter stronger spokes my be part as well, or so I'm told. I asked Trek for a response to your concerns. Customer service promised an appropriate person would get back to me, ASAP.
Enough already!! Drop it!!
The fight is over.

P.S. I asked for a brifter version, and also asked for a carbon version. I wonder if they will do either.

elcruxio

Box section rims, Vee rims, shorter spokes and all that is all very fine, but we know all that already. It's not like we've been riding single wall steel rims for all this time and now Trek has come up with new fancy technology like very basic rim desing that has been out for ages already. Furthermore, all the bontrager wheels I've been fiddling with lately have been with straight gauge no name spokes, which don't really inspire confidence as they aren't as durable as double butted or triple butted spokes which could easily be used to create a stonger wheel. Hence it'll be interesting to see what Trek has to say about the spokes in the 920 wheels. If they are non butted I can pretty much rest my case. And there are other factors as well that have been discussed in other topics over the years such as deflection, rim stiffness etc. And not to mention that even with today's high stiffness rims, the spokes are still the most important part of the equasion. Yes, there are quite functional 20 spoke wheels out there, but for heavier riders those almost require a carbon rim to really be worth anything.

Maybe try to end a thread without yourself strutting as the winner? Might help.

Happy Feet

...

saddlesores

oh, that's different!

axed the salesman, and he said "don't worry, mate, our bikes be da
bestest!.......now about that undercoating..."


i am properly chastened. TFSM forbid i question salemen or engineers!
does that mean my VW diesel really meets emission standards?

Happy Feet

I'm not sure why, but I can't read past LeeG's post except in post preview mode. Weird?

I think someone needs to realize that people are discussing design features without getting all defensive about a bike. What fight? I suspect it's symptomatic of the perception that the bike will somehow define the person, thus criticism of it - is criticism of them. I don't even see it as criticism of his bike because technically, it's not your bike until you actually buy it

We are discussing spokes and axles. I'm kinda wondering how the spokes got shorter on a 28" rim when 32-36 spokes are sought for 26" mtb rims?

Ghazmh

Is the 720 any good? I almost considered it as a fast and lighter day touring stablemate to my 520.

LeeG

Looks great, and it has 24 spoke wheels!

Read the comments

Review: Trek 720 Disc light adventure touring



Any experience with spokes breaking on new Trek 720 touring bike - Bicycles Stack Exchange

djb

21lbs for a 58cm frame, without pedals. That is still rather impressive. I'd still want a triple, but hey, unless someone actually puts a gun to your head and forces you to buy one, its up to you to look at other options and or have the experience to know that perhaps you need want lower gearing and diff wheels for what you plan to carry.

Squeezebox

Thanks for the info about the 720. It's hard to get info like wt, and spoke count from the companies.
By the way my Giant around town bicycle broke 2 spokes the 1st month. They replaced the wheel no problems since, but yes shouldn't happen to begin with.
There are a few CC/ fast tour carbon bicycles worth looking at. Simular geometry and gearing

HTupolev

Spoke count is usually pretty easy, as you can just count the spokes in the pictures.

Sharpshin

Ouch! Aluminum frame and rigid fork?

Perhaps aluminum frames and forks have improved by leaps and bounds I dunno but I just think that thing would beat me to death off-road. In fact I'm having flashbacks to my previous rigid mountain bikes 15-20 years back, fattest tires I could find back then (2.2?) notwithstanding.

I LOVE the compliant ride on my steel-framed '89 Schwinn Voyageur, in fact I think I'd rather take IT down a dirt/gravel road than the rigid Mt. bikes I had.

JMHO,
Mike

djb

aluminum frames aren't too shabby nowadays, throw in the factor of wider tires and its not a problem, again, in my opinion of riding alu frames for a while now. The big factor is the tires and tire pressures.

saddlesores

do these yahoos reviewing touring bikes have any touring experience?


24 spokes on a touring bike?

"...This is a bike designed to be loaded down..."

and take that load uphill?

"The 11-32-tooth, 11-speed cassette offers low enough gearing to handle long, steep climbs, and the 50/34..."

ah, i get it now....

"... become a mule on longer overnight excursions..."


and coming back to reality.......

"...just finish my trip through Europe. 7 spokes broken, 6 on the back, 1 on the front, I was carrying 25kg on the back and about 10kg on the front.
When I finished my trip, I wanted to change the wheel, however, it's a 11 gears with a disc.. Even the trek shop of my arrival city coudn't sell one to me....."


WOW!!! 2 freakin' grand for wall art!

LeeG

Glad to help, I utilized the services of Monsieur Google and Treks website, you can count the spokes! See, the folks who market a product aren't engineers or even users of that product. The total package is designed to sell primarily and work secondarily. If it sells it works. This isn't rocket science, it's not a fight, it's not about you or me. There are some elements that are bling and some elements serving a designed purpose for use. The Trek 520 has wheels designed to carry weight reliably over time and distance. Just so happens to be 36 spokes. It could also be 32 spokes but 36 it is. Then there's the 24 spoke 720. Sigh. So maybe 28 spokes is better for the 920. But the point is if you're marketing four pannier capability with a big front rack and and rear rack included with the bike you're implying a fully loaded bike capability like the 520. So why 28 spokes and not 32-36?

I am confident 28 spokes is sufficient for unloaded riding with big tires. I am confident 28 spokes with a loaded bike guarantees a rear wheel replacement in a couple years. It's like deciding to putting performance tires on your automobile and being ok with them lasting 15k miles. Nothing wrong with that, look at all the performance you got.

PDKL45

That's exactly what I do.

Squeezebox

I'ld love to hear from Trek as to why they made the spoke count decision. Maybe even some data sheets about the stress tests.

elcruxio

It's unlikely that it's more than marketing fluff. I've seen some really weird desicions done by bike companies just because it's 'cool' or more marketable, even in high end bikes. When considering wheels, if the design isn't conservative (evenly spaced spokes on the rim, enough spokes for the intended activities etc) it's more than likely that the desing is weaker than it's conservative counterpart. There's nothing special in wheelbuilding, it's actually really, really simple all in all.

There is of course a possibility that a low spoke count wheel has been built in a fashion that it has the required strength for high impact applications, but those wheels are usually very expensive, pretty much in the price range the whole 920 would cost. Those wheels usually have extra high spoke tensions and a very, very stiff rim (preferably carbon as it's way more durable than aluminum) as well as other bracing methods to make the wheel stronger. As it is however, the 720 and 920 employ affordable factory wheels, which usually is not problem at all if you have enough spokes as you can retension them completely or with any luck just do a few tension adjustments and a few extra cycles of stress relief. The bontrager rims are nothing spectacular so you'll need to be conservative with spoke tensions and with 32 or 36 spokes this is not an issue. But with less spokes as you can't push over a certain spoke tension limit you'll still have conservative spoke tension, but the peak stress (or rather, slackening) that every spoke faces is significantly higher as the spoke spacing is also much higher (this is still very basic wheel building science). This means that every spoke is at much higher risk of losing tension at every wheelspin on a loaded rig, or at least at every single small bump on the road. With more spokes you'll have more spokes taking the stress and slacking effect as the spokes are more tightly spaced. A spoke that loses enough tension at frequent enough intervals is a broken spoke quite quickly. Some of this effect can be helped with double or even triple butted spokes, but none of the spokes I've had or seen in bontrager wheels have been butted so all in all it's a SOL situation.

Theyr'e just trying to make a profit. Not to provide everyone with the best possible bike at every situation. Of course bike companies usually try to create really good bikes, but sometimes bike companies make massive mistakes. The 520 is a really solid tour bike and one of the best in the whole of Trek line, but the 720 and 920 at least this year are pretty shifty and weird really.

saddlesores

Melvin: uh, neville, have you finished the spec sheet on our new grrrravel grrrinder?
Neville: not quite yet, got a few more items. hey, what did our engineering team
recommend for wheels?
Melvin: silly rabbit, your forget the engineering department was outsourced to calcutta
three years ago?
Neville: oh, yeah....hey, do they even have bikes in calcutta?
Melvin: not per se.......mostly they jsut have cast iron samlors, you know, pedicabs and
delivery truck bikes.
Neville: right, so what do they know about touring bikes over there?
Melvin: not much....but they work cheap as hell.
Neville: gotcha....so they know about as much as we do. so what about these wheels?
Melvin: not really important. wheels is wheels. they're round with black bits on the outside.
just pull something from one of our other bikes.
Neville: let's see......how 'bout some wheels off the 520? plenty left over, seems
every old fart this year wants to go adventure. not as much demand for real touring bikes.
Melvin: oh, good lord, no! division will have our asses! 520 wheels have 36 spokes! spokes cost .00005 cents each! we'll never make our price point! find some 32 spoke wheels.
Neville: but melly, we've got expedition racks on this bike! customers are gonna load up
the bike and go off road! they'll implode!
Melvin: not to worry, nev. it's just illusion. our marketeers are top-notch....ain't nobody gonna
take this piece of poo off road......it's just for posing at starbucks. it's 90% certain they'll
be mounted permanantly to the roof of somebody's prius. as we all know, serious cycle
tourists will buy an LHT....cause ya know, steel is real!
Neville: ooooooooh, well in that case, why don't we just throw on some lame 28-spoke
junk. i think we have a container left over from that failed krusty the clown promotion.
Melvin: Nev, you're a genius!
Neville: Doh!

Squeezebox

I just spent some time looking at Co-motion tandems, particularly spoke count and frame material.
Of their 5 touring models 1 uses 24 spoke wheels, that one is their most expensive tourer.
Of their 5 road tandems 4 use the 24 spoke wheels, 2 of the models are aluminum frames.
A tandem puts up with much more severe weight & stess than any touring single possibly could.

elcruxio

But a tandem also has a 145mm rear spacing, so the wheel is not dished (I'll emphasize this, the difference between a 145mm and 135mm wheel is massive, huge!). A non dished wheel is extremely more durable than a dished wheel. I'd wager a 24 spoke tandem rear wheel is probably as durable as a 32 spoke or even a 36 spoke dished wheel. It's the exact same reason you can get a 16 spoke front wheel and it might be good enough if it's well built, but putting 20 in the rear and you're really pushing the envelope. That's even most high end rear's are 24, rarely do you see a 20 spoke rear especially in road spacing.

LeeG

And yet there's those various postings about Trek 720 24 spoke wheels breaking still exist. Maybe they aren't the same wheels?

i just looked at the touring page, they all have 32 spokes.

https://co-motion.com/bikes/bikes-grid-touring

mstateglfr 

Ill say I am surprised to see 24 spoke tandem wheels, even though they are 145 in the rear. Of course, I know nothing about tandems and you can choose to get higher spoke'd wheels from CoMotion if you they are building something for you, so my surprise is just plain ignorance on the issue.