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#31
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SM+ question: 700x35c -or- 700x38c for Chicago year round ?commuting?
someone wrote:
You are absolutely right, Sir! It IS bent!! Bent seatposts are a sad fact of my cycling life. Thomson Elite posts are a sure cure, though they are expensive by seatpost standards. I have used an almost 12" exposed section of 27.2mm Thomson post when my weight exceeded 400 lbs., and that post never failed. Another option that should work fine for you (at a more appealing price point) is the Kalloy 350mm 4130 heat-treated chromoly steel post. Oddly, these are not as resistant to bending as Thomson posts, but they are more than strong enough for your application. How does a seat post fail in one month of use? Bad steel? Bad match with the frame? Both? Long extension with a laid back seat angle plus a good sized rider. It's basic lever physics. In a perfect world Electra would sell a 24" version of this bike, but as it's a one size fits all deal, you're going to have to find a post that's stronger as you're out of the expected "range" that it's supposed to fit. Bending is not failure as I see it. However, operating at yield stress (the stress that leaves permanent bends) leads to fracture, which is a significant failure because it generally causes serious injury. With todays sloping toptubes, seat posts must be excessively long and are operating at stress levels not incurred with "old fashioned" frames with horizontal toptubes at reasonable height with which thin walled aluminum seatposts worked well without fail. The Kalloy should work--provided it's long enough. Jobst Brandt |
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#32
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SM+ question: 700x35c -or- 700x38c for Chicago year round commuting?
In article ,
Werehatrack wrote: On Tue, 1 Apr 2008 13:19:37 -0700 (PDT), landotter may have said: On Apr 1, 3:41*pm, Werehatrack wrote: On Tue, 1 Apr 2008 04:49:41 -0700 (PDT), Jay may have said: RTC is having trouble getting my spec'ed 700x38c SM+ tires (backordered). They do have the same tire in 700x35c. I am 210lbs, 20lbs cargo (pack on the rear rack + small backpack), 5000 road miles per year. Should I just go with the narrower tire? 3mm isn't all that much, but in this case I'd simply swap to a different 38. * A 35mm gumwall tire can take a heck of a load and abuse. I wouldn't worry. Yeah, back in the '60s, I delivered a paper route on a bike with EA3 rims, and 26 x 1 3/8 is about a 35mm tire equivalent. As long as I didn't let the pressure sag, it didn't give me many problems with pinch flats. Now, these damn 23mm tires on the current roadie are another matter; I'm definitely swapping up to 28 this weekend. Two pinch flats in one week is three too many. There is a big difference between 23 and 25. Try the 25. 25's come in 128 threads per inch, but 28's only 67 tpi. I had some 23's and immediately went to the 25's; happy ever since. I run 32 nominal 28 actual on a utility bicycle where they are functional, but not nearly the fun of the 25's. -- Michael Press |
#33
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SM+ question: 700x35c -or- 700x38c for Chicago year roundcommuting?
On Apr 2, 4:45*am, "
wrote: On Apr 2, 11:11*am, Andre Jute wrote: On Apr 2, 7:47*am, " wrote: On Apr 2, 1:17*am, Andre Jute wrote: On Apr 1, 12:49*pm, Jay wrote: RTC is having trouble getting my spec'ed 700x38c SM+ tires (backordered). They do have the same tire in 700x35c. I am 210lbs, 20lbs cargo (pack on the rear rack + small backpack), 5000 road miles per year. Should I just go with the narrower tire? J. I weigh the same as you. I have 35mm Schwalbe Marathon Plus on my Gazelle Toulouse and 38mm Bontrager Satellite Elite Hardcase tyres, very similar to the SM+, on my Trek "Smover". I can't tell the difference between the tyres in service in comfort or longevity; I don't even see that they vary in responsiveness; I see no reason the 35mm (1 3/8 inch) Marathon Plus won't suit you as well as the so- called 38mm (it's probably 40mm). I can tell you though that, having seen the pictures of the SM+ construction and then felt the stiffness and weight of the tyre as I was fitting it to the rim, I was very surprised that the ride wasn't harsh when inflated as highly as the manufacturer suggests. I see Chalo has noted this as "softened" ride in his last post; I'm a hedonist with a sprung seat and fork on all his bikes who pines for something as soft as Big Apples with the low rolling resistance and quick response of the SM+, so I won't go quite as far as Chalo; I'll just say that all the tyres I ever had on my mountain bikes were a lot harsher than SM+. And the height of the sidewall is good too, for the puncture mode on the Contis I had before was double pinch flats picked up in riding too hard through the ubiquitous potholes. Not a single flat in 5100km between the Marathon Plus and the Bontrager Hardcase, so those tall sidewalls and those rubber belts work for their living, and so they should for these are pricey tyres. Andre Jutehttp://members.lycos.co.uk/fiultra/BICYCLE%20%26%20CYCLING..html All cyclists should ride in dignity as we do What's the manufacturer's recommended pressure? How can they know what it should be? Joseph Eh? Every tyre manufacturer recommends a range of *inflation pressures for his tyres. It is usually embossed in the rubber of the sidewall. He knows how much it should be by empirical tests to meet the design specification. The Bontrager Satellite Elite Hardcase on my Trek "Smover" should be inflated between 50 and 85psi. *And the Schwalbe Marathon 700x35c/x40c like Jay is getting and I have on my Gazelle Toulouse should be inflated between 3.5 and 6 bar. I keep mine a fraction above the middle of those ranges. Andre Jutehttp://members.lycos.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html The ranges printed on sidewalls are so huge as to be meaningless. Useful pressures are dictated by the size of the tire and the load, as you have found no doubt by experimentation. http://sheldonbrown.com/tires.html#pressure Joseph- Hide quoted text - - Show quoted text - Yep. Tire pressure ranges (printed on the tire) are dictated by the marketing and legal depts, as SB wrote. Not the engineers. J. |
#34
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SM+ question: 700x35c -or- 700x38c for Chicago year roundcommuting?
On Apr 3, 8:12*am, Jay wrote:
On Apr 2, 4:45*am, " wrote: On Apr 2, 11:11*am, Andre Jute wrote: On Apr 2, 7:47*am, " wrote: On Apr 2, 1:17*am, Andre Jute wrote: On Apr 1, 12:49*pm, Jay wrote: RTC is having trouble getting my spec'ed 700x38c SM+ tires (backordered). They do have the same tire in 700x35c. I am 210lbs, 20lbs cargo (pack on the rear rack + small backpack), 5000 road miles per year. Should I just go with the narrower tire? J. I weigh the same as you. I have 35mm Schwalbe Marathon Plus on my Gazelle Toulouse and 38mm Bontrager Satellite Elite Hardcase tyres, very similar to the SM+, on my Trek "Smover". I can't tell the difference between the tyres in service in comfort or longevity; I don't even see that they vary in responsiveness; I see no reason the 35mm (1 3/8 inch) Marathon Plus won't suit you as well as the so- called 38mm (it's probably 40mm). I can tell you though that, having seen the pictures of the SM+ construction and then felt the stiffness and weight of the tyre as I was fitting it to the rim, I was very surprised that the ride wasn't harsh when inflated as highly as the manufacturer suggests. I see Chalo has noted this as "softened" ride in his last post; I'm a hedonist with a sprung seat and fork on all his bikes who pines for something as soft as Big Apples with the low rolling resistance and quick response of the SM+, so I won't go quite as far as Chalo; I'll just say that all the tyres I ever had on my mountain bikes were a lot harsher than SM+. And the height of the sidewall is good too, for the puncture mode on the Contis I had before was double pinch flats picked up in riding too hard through the ubiquitous potholes. Not a single flat in 5100km between the Marathon Plus and the Bontrager Hardcase, so those tall sidewalls and those rubber belts work for their living, and so they should for these are pricey tyres. Andre Jutehttp://members.lycos.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html All cyclists should ride in dignity as we do What's the manufacturer's recommended pressure? How can they know what it should be? Joseph Eh? Every tyre manufacturer recommends a range of *inflation pressures for his tyres. It is usually embossed in the rubber of the sidewall. He knows how much it should be by empirical tests to meet the design specification. The Bontrager Satellite Elite Hardcase on my Trek "Smover" should be inflated between 50 and 85psi. *And the Schwalbe Marathon 700x35c/x40c like Jay is getting and I have on my Gazelle Toulouse should be inflated between 3.5 and 6 bar. I keep mine a fraction above the middle of those ranges. Andre Jutehttp://members.lycos.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html The ranges printed on sidewalls are so huge as to be meaningless. Useful pressures are dictated by the size of the tire and the load, as you have found no doubt by experimentation. http://sheldonbrown.com/tires.html#pressure Joseph- Hide quoted text - - Show quoted text - Yep. Tire pressure ranges (printed on the tire) are dictated by the marketing and legal depts, as SB wrote. Not the engineers. J.- Hide quoted text - - Show quoted text - QED. J. |
#35
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SM+ question: 700x35c -or- 700x38c for Chicago year round commuting?
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#36
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SM+ question: 700x35c -or- 700x38c for Chicago year round commuting?
On Wed, 02 Apr 2008 12:50:33 -0700, landotter wrote:
On Apr 2, 2:38 pm, wrote: 6'4" isnt that tall. They must make a frame that fitswith normal seatpost extension!!!! They must? I'd email them with a few of those exclamation points and let them know. As it stands the Royal 8 comes in one size. With compact frame sizing, modern strong posts, long headtube, and an adjustable quill, it can fit a big range of people--but 6'4" is on the tall end. I can understand why Electra would try to make a one-size- fits-most with this bike, as a $1K city bike is an unusual thing to risk stocking on the sales floor in the US--much less in 4-5 sizes. 6'4" is definitely on the tall end of things, as far as bikes are concerned. There are not a lot of mainstream bikes with frames available to fit riders that tall very well. Even at 6' I find the front ends of most bikes too low as they come from the factory. Even with tall stems on my bikes, my bars are lower than most people's (~4" drop from the saddle). I don't think the bike industry does a very good job accommodating tall or short riders. It's actually worse with short riders. Tall riders are usually accommodated well with tall stems and seatposts, but it requires spending extra money. Matt O. |
#37
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SM+ question: 700x35c -or- 700x38c for Chicago year round commuting?
On Wed, 02 Apr 2008 14:48:06 -0700, Michael Press wrote:
In article , Werehatrack wrote: On Tue, 1 Apr 2008 13:19:37 -0700 (PDT), landotter may have said: On Apr 1, 3:41*pm, Werehatrack wrote: On Tue, 1 Apr 2008 04:49:41 -0700 (PDT), Jay may have said: RTC is having trouble getting my spec'ed 700x38c SM+ tires (backordered). They do have the same tire in 700x35c. I am 210lbs, 20lbs cargo (pack on the rear rack + small backpack), 5000 road miles per year. Should I just go with the narrower tire? 3mm isn't all that much, but in this case I'd simply swap to a different 38. * A 35mm gumwall tire can take a heck of a load and abuse. I wouldn't worry. Yeah, back in the '60s, I delivered a paper route on a bike with EA3 rims, and 26 x 1 3/8 is about a 35mm tire equivalent. As long as I didn't let the pressure sag, it didn't give me many problems with pinch flats. Now, these damn 23mm tires on the current roadie are another matter; I'm definitely swapping up to 28 this weekend. Two pinch flats in one week is three too many. There is a big difference between 23 and 25. Try the 25. 25's come in 128 threads per inch, but 28's only 67 tpi. I had some 23's and immediately went to the 25's; happy ever since. I run 32 nominal 28 actual on a utility bicycle where they are functional, but not nearly the fun of the 25's. I agree, 25s are better and most people should be riding them instead of 23s. The problem is finding them at a good price when you need them, and being able to get them through the brakes when removing the wheels. Tires bigger than 25 would be better still, but road frames and brakes don't accommodate them these days. Some frames, like the Scott carbon ones, won't even take 25s. I could probably put 28s in my Klein frame, but they wouldn't fit through the brakes. Even 25s are a tight squeeze. Matt O. |
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