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General Category >> Technical >> 650 vs. 700 -- why one or the other?
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Message started by FlyingLaZBoy on Jun 15th, 2009, 4:09pm

Title: 650 vs. 700 -- why one or the other?
Post by FlyingLaZBoy on Jun 15th, 2009, 4:09pm

I know there's a massive lack of standardization out there in wheel/tire sizings, specs, etc. -- but if one were to limit oneself to the "26+ inch" sort of range, there seem to be three basic categories:  a) "559," or "26 inch,"  b) "650," and c) "700"

The "559/26inch" appears to be common to both MTBs and recumbents, at least in my experience.  However, obviously RANS and other manufacturers continue to come out with either "650c" or "700" versions -- and there seem to be a VERY limited range of tires available for the "650" spec.  But if you design for a 650, you can't necessarily change to a 700 due to frame fit, brakes, etc.  Yet there is a much wider range of tire widths (up to ~40mm) available for 700!

So given this, what's the advantage of going with 650 over 700 on a new bike design?  Or vice versa?  Is a reason for 650 at least in part to reduce the "heel strike" issue slightly, to reduce the fork extension required on a LWB?  Is the acceleration difference of a 650 that significant over a 700?

Title: Re: 650 vs. 700 -- why one or the other?
Post by jcsadowski on Jun 15th, 2009, 4:32pm

I was told that the 650 invented for people who were shorter. Years back, for example, woman's bicycles had 650 wheels but lately most of the manufactures  have switched to the 700 wheel.
Since fewer bikes are coming out with 650 wheel, there is a thought that someday the 650 wheel may go away.
I found this out because the CA 2/0 comes with 650 wheels now but Bachetta will be making a frame set with 700 wheels

Title: Re: 650 vs. 700 -- why one or the other?
Post by evblazer on Jun 15th, 2009, 4:47pm

In my experience, which isn't much, 650 and 559 (26") tires make many bikes like highracers beyond the reach of many casual users due to stop/start seat height. The larger 700 (same diameter but smaller then the new 29er) wheel may present heal strike issues, or crank strikes but from what I have seen on dual bikes they push the seat up a bit too cutting even more people from using them.

I'd think with a long reach caliper you could fit a 559 wheel/tire on a 650 bike without much problem? Sort of like fitting a 700c tire on a an old 27" wheeled bike. Now finding a narrow 559 rim is a bit of a pain.


Title: Re: 650 vs. 700 -- why one or the other?
Post by kingjason on Jun 15th, 2009, 6:12pm

The Velocity Thracians are 559's and pretty narrow. Mine have 559x20 tires on them. They are a really stout wheel too since I am like 275 or so and no problems other then a chain issue.

Title: Re: 650 vs. 700 -- why one or the other?
Post by Kwijybow on Jun 15th, 2009, 7:01pm

Don't forget 650B (584).  I have at least one bike for every wheel size mentioned below.   650c become vogue again in the 90's due to a triathlon fad with smaller wheels and to a smaller extent the need to fit shorter women.  If not for that peformance recumbents would have likely stayed with something else.  26" / 559 in performance sizes are only around because of bents I believe though (maybe junior racers).  I think thanks to Bacchetta, and other Hi -Racers 650c has been given a  new lease on life.  For somebody short like me the 650b size makes a lot of sense on a DF, but the available rims and tires are oriented towards touring, because that was the traditional use, first in France, and later adopted in Japan.  I think we're going to be good in the future though, because unlike cars - bikes are going to become increasingly important and more universally used.  I think we'll see all sizes stocked and available for a long time, especially the more utilitarian types.


so 26"+

559 (26" MTB) lots of stuff
570 (650c) much better selection than there used to be thanks to Performance Recumbents and women specific bikes
584 (660b) much better selection than there used to be thanks to MTB, and Randonneuring
622 (700c + 29" MTB) lots of stuff

stuff not mentioned 650a, 26x1 and 3/8, 27"  all still available.

There are so many more tires available in every category than there were just 25 years ago its not even funny.

Take Care,
Nelson.


Take Care,
Nelson.

Title: Re: 650 vs. 700 -- why one or the other?
Post by kingjason on Jun 15th, 2009, 7:45pm

No difference in 26x1 and 559 right??

Title: Re: 650 vs. 700 -- why one or the other?
Post by evblazer on Jun 15th, 2009, 9:28pm

26x1 on a bent especially a bacchetta or rans should be a 559 I think.. 650 usually say 650x25 but I have seen them listed online as 26x1.
Tis why it is very important to get the 3 digit number and not just the inches. I bought some 20" tubes and they were the wrong 20". They were 451 instead of 406, or maybe they were 419 ugh :-[  Most all tires will have a 5 digit number with a - in it with 3 numbers on one side and 2 numbers on the other such as 50-406 which are much current tires or 37-406 which were my old tires I'm too heavy for according to the company.

Lot of tires sizes listed over here though many you are going to have a hard time finding much if any selection in.
http://www.sheldonbrown.com/tire-sizing.html

There was a time that terry made bikes with 700c back and a 24" front wheel, or perhaps they still do for really small sizes. To avoid problems on really small framed bicycles for women because there was severe toe strike. I remember reading how there were some mens bike that used 650c for the front for lower aero losses and a 700 in the back for more power or a bigger gear or some such.  If i remember correctly you now have to use the same size wheels front and rear in the big bike racing association so they cut that practice out.

Title: Re: 650 vs. 700 -- why one or the other?
Post by kingjason on Jun 15th, 2009, 10:29pm

I asked about the 559 or 26x1 because I am going out to locate a replacement tommorrow. My tires say 559x20 comet racers on the side. The wheels are the Velocity Thracian. However the website states 26x1 on the V3 steel. I had forgot the guy put these on as aftermarkets. Hmmmmm  I guess with discs it doesnt matter but I would like to stick with the same size. Didnt think about it but I guess I could go with 650's..

Yeah I also almost bought a 20 1/8 contenental for my bachetta but it was actually a 401 and the 20 1/8 was a 451 I think. He said something about metric sizes and so on.

Title: Re: 650 vs. 700 -- why one or the other?
Post by evblazer on Jun 15th, 2009, 10:39pm

If the tires you have been riding say 559 it is almost certain you have 559 rims and need 559 replacement tires. If they were 650 rims they'd probably be harder to get on then marathon plus tires on a mavic 319 rim (Tire diameter on the small side and rim diameter on the large side) if you could get them on at all.

The primo comet racer 26x1 is a 559 tire. I don't think Primo makes a tire in 650.

Title: Re: 650 vs. 700 -- why one or the other?
Post by kingjason on Jun 15th, 2009, 10:50pm

OK I htought so. YOu scared me with the 26x1 listed as 650 thing. I wish they would all go to one or the other.

Title: Re: 650 vs. 700 -- why one or the other?
Post by evblazer on Jun 15th, 2009, 10:57pm


kingjason wrote:
OK I htought so. YOu scared me with the 26x1 listed as 650 thing. I wish they would all go to one or the other.

I think it came from the fact that a normal 559 tire and a normal 650c tire are both around or equal to 26" because the 559 tire was traditionally a fatter mtb tire and a 650c was a 23mm speed tire. At least that is what some old crazy guy once told me.
If people would just get off inches it would be alot less confusing.

Title: Re: 650 vs. 700 -- why one or the other?
Post by Kwijybow on Jun 15th, 2009, 10:59pm

I  actually had one of the Terry bikes with the 24" front wheel for my daughter, but she now rides a 26" (559) wheeled hybrid.  

It handled pretty well actually.

I'm certain the V3 will take most narrow mtb slicks.  My Bacchetta Strada is currently shod with the performance Metro K's, very durable, very cushy, and now that they have nearly 500 miles on them they are starting to roll a little faster I think. Cheap as dirt.

Take Care,
Nelson.

 

Title: Re: 650 vs. 700 -- why one or the other?
Post by FlyingLaZBoy on Jun 16th, 2009, 9:44am

One reason I'm asking this is from a "bike versatility" standpoint.  When I had the Proto XStream, I tried to change the rear (650) tire from a 23mm to a 28mm, and there wasn't enough frame clearance -- it rubbed against the back end of the main frame tube.  This prompted an immediate discussion with Randy, and he did a "running change" on the frame design to increase the clearance to accept wider tires.  

However, I think the widest tire you can even obtain in 650 is the 28mm, and I'm not sure if you can retrofit the brakes and fit a 700 on the back or not on the production XStream -- granted, you would lose additional recline angle due to reduced seatback clearance, again.  But, given the ~65:35 (or worse) weight distribution on bikes like the SXP, V3, and XStream, it just seems like having the ability to have tires wider than 28mm on the back makes good sense.

I've read various things about how 650 was brought out to help shorter riders and women -- but why are recumbent companies designing for 650s while not leaving room for an easy change to 700s?  Granted, I'm sure there are issues like brake tabs, etc. involved that I don't know the specifics of.

Title: Re: 650 vs. 700 -- why one or the other?
Post by evblazer on Jun 16th, 2009, 10:19am

Isn't the standard V3 fitted with discs and 26" (559) wheels? I'm not sure how wide it can take but some builders use discs to allow for wider tires. Some just use discs because though so that isn't the best indicator. Can't you put 559 wheels on an xstreme for wider also which gets you the wider tires?

700C tires are 622mm bead set diameter and 650c are 571mm bead set diameter which is 2 inches different diameter or an inch taller between the axle and the braking surface? Also an inch difference between the axle and where the tip of the tire hits the arch in the frame or fork. I think the Giro 26 is one of the few frames/forks that is setup to use both due to disks but also for the fork/rear chain chainstays. If I remember correctly if you put a 700C wheel on a Giro 26 you have to use pretty narrow tires compared to what you can do on the 26(559).
That kind of thing also slightly changes the handling but maybe not enough to be noticeable by mere mortals.

Title: Re: 650 vs. 700 -- why one or the other?
Post by Kwijybow on Jun 16th, 2009, 11:24am

I think the delta between 622 and 571 is big enough that designing a bike with the option for either is difficult.  However,
622 <-> 584 is doable (I've done it on the Lemond, and now my Davidson.  571 <-> 559 is also close enough to run both and I do it on the Corsa, and Strada.  Now why you choose the smaller wheels is likely due to trying to fit more folks than just going with 622 would have allowed.  

I think Bacchetta made a good decision to go with the 650c / 571 wheels with the option to mount 26" / 559 for utility riding.  However on my 2006 Corsa the tolerances are so tight that there are 23c tires I couldn't run without modifying the brake bridge (ie filing).  At least that is better on the newer models, as I think they can run up to 28mm.  

All that said, on a LWB where one's reach to the ground is lower naturally I would think there are less reasons not to just go with the 700c / 622 or 26" / 559 size and be done with it.

Take Care,
Nelson.

Title: Re: 650 vs. 700 -- why one or the other?
Post by Opus the Poet on Jun 16th, 2009, 3:17pm

From discussions on DF boards years ago the 650 size is more aerodynamic, but the 700 size has less rolling resistance. Now how much of that is true and how much is "everybody knows" kind of "stuff" I coiuldn't tell you. I know there are a lot of triathlon bikes with the 650 wheels, but I don't see as many coming out as I used to.

Title: Re: 650 vs. 700 -- why one or the other?
Post by FlyingLaZBoy on Sep 13th, 2009, 1:36pm

There was a recent thread on BROL that diverged into a discussion of wheel/tire sizes on the Xstream, where someone was wanting to put 1.5" tires on it, based upon some comments made a while back about the bike accepting wider tires.  To do this, obviously, you have to go to 559 wheels, since 1.5" tires aren't available in 650c...  but apparently, the stock fork on the Xstream is not wide enough to take this size tire.  Not having one, this came as a surprise to me, since the front fork on the prototype is the same as that on the StratusXP, as far as I can tell -- apparently the production fork is something different, that is narrower.

You'd probably have to change out the brakes as well, I suppose, to get the tire width to fit in between the pads.  I have put my 559 Thracian wheels with 1" tires on the XS prototype, and everything fits fine (and yes, Greg,  :D I adjusted my brake pad rim contact positioning...) -- although I guess if you needed to, you could deflate a 1.25" or wider tire, get it through the brake arms, then reinflate it!   Kind of like the classic puzzle of how you get a 14' tall semi truck under a bridge with 13' 11" clearance -- let some air out of the tires!   [smiley=thumbsup.gif]   Although I do remember Ray talking about front brake clearance issues on his bike....

Title: Re: 650 vs. 700 -- why one or the other?
Post by Kwijybow on Sep 13th, 2009, 2:28pm

Yeah there is a point where you have to say enough is enough.  An Xstream is not meant to be a Stratus XP, so support for 1.5" tires would be a very secondary design parameter.  I have found in my experience however that it is easier to make a fast bike utilitarian than a utility bike fast.  So I tend to buy a faster bike and work around the limitations when I want it to do more than just go fast.

Take Care,
Nelson.

Title: Re: 650 vs. 700 -- why one or the other?
Post by goatstick on Sep 13th, 2009, 3:21pm


Opus the Poet wrote:
From discussions on DF boards years ago the 650 size is more aerodynamic, but the 700 size has less rolling resistance. Now how much of that is true and how much is "everybody knows" kind of "stuff" I coiuldn't tell you. I know there are a lot of triathlon bikes with the 650 wheels, but I don't see as many coming out as I used to.

The difference in tires themselves (models, manufacturers etc.) and tire sizes tends to be much larger than the difference between the wheel sizes themselves. 650s are primarily used on women's tri bikes right now. Those and high-racers might be the only bikes that have an actual point in using them. Why do you ask?

I still laugh about the tri shop owner in Fred'burg telling me about decided to stock up for the 'women' just before Hell Week, only to have the highracers discover him and wipe out his entire 650 stock. :^)

Title: Re: 650 vs. 700 -- why one or the other?
Post by FlyingLaZBoy on Sep 13th, 2009, 5:05pm


Kwijybow wrote:
Yeah there is a point where you have to say enough is enough.  .....  I have found in my experience however that it is easier to make a fast bike utilitarian than a utility bike fast.  


Well, the frame IS already designed for wider rear tires, so to have an Xstream "cruiser" you'd just need a Stratus XP fork and canti or disc brakes.  There's also a couple photos of the RANS rally that show the silver and gold painted Xstream that has a Zephyr seat on it...

Mods, mods, mods....   [smiley=laugh.gif]

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