Potential Catastrophic Frame Failer Averted ….sort of.

General Discussion about electric bicycles.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Buk___ » Jan 18 2018 4:51pm

liveforphysics wrote:
Jan 18 2018 4:50pm
My bike is 18.5lbs fully assembled with cyclocross tires. I don't know the bare frame weight.
I read bad info. I've corrected my mistake above.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Buk___ » Jan 18 2018 5:24pm

liveforphysics wrote:
Jan 18 2018 3:28pm
Everyone has a different kind of riding preference.
Even on my road bike, I look for the biggest sets of stairs to drop or climb, and ride over log piles and aggressive downhill trails, and it still feels like inadquate training for cyclocross racing.
Would you agree that you are an outlier on the spectrum of people riding 1.5kg racing frames?

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by liveforphysics » Jan 18 2018 6:55pm

Buk___ wrote:
Jan 18 2018 5:24pm
liveforphysics wrote:
Jan 18 2018 3:28pm
Everyone has a different kind of riding preference.
Even on my road bike, I look for the biggest sets of stairs to drop or climb, and ride over log piles and aggressive downhill trails, and it still feels like inadquate training for cyclocross racing.
Would you agree that you are an outlier on the spectrum of people riding 1.5kg racing frames?

In a decade of testing batteries my lungs have been exposed to a lot of nasty fluorine containing vapors and gases that scarred them inside, so even if I sprint until black-out it's not enough to make passes on healthier stronger riders, so my passing options happen almost exclusively in technical sections. That said, I still get passed in technical sections myself sometimes, so I can't be the only one who trains for aggressive obstacles on a road bike. My guess would be everyone in a cyclocross race qualifies as the 'outlier' group of riders who are rougher on bikes than most.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by MadRhino » Jan 18 2018 8:02pm

Cyclo cross had gained a lot in popularity here, since I quit about 10 years ago. It is a very tough disciplin. Courses are designed to push participants to their limits of strength and aerobics. I was too old to be competitive, but had a lot of fun trying.

I was riding a Specialized Tri-Cross Expert double, alu-carbon. I guess that most are carbon today, and your steel frame must be one among very few in the races.

In DH too, carbon frames are taking over, about half of them right now. The other half are alu. Trying to find a steel DH frame, one would need to look at 20 yr old bikes.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by speedmd » Jan 18 2018 10:34pm

I ride my circa 1150 gram (54) full carbon frame cross bike on some well worn rocky bike trails also with many of the mtn bike group in the fall. Not racing any longer, but still can stay with many of the fast guys on the climbs. Bombing the down hills, is difficult to stay with them unless it is somewhat smooth without flatting much too often. Lots more work for certain on a ridged frame narrow tires and no suspension. Head sets don't last very long and wheels do get messed up a bit too often. A few of the A riders were riding steel frames up until the last few seasons, but no longer. They have mostly gone to single chain rings up front and 11 speed now. Most fast builds are down to 16 pound area now. Most of the newer frames are even lighter than mine which built up well under 18 pounds with medium weight stuff. Way stiffer and stronger than my classics that are near 20 pounds with near equal components. I would not even think about jumping the logs and boulders on my steel bikes that I regularly do on the carbon one. Only so much you can expect from small diameter tubing. Carbon forks would take some 6- 8 ounces off them. They are relegated to fair weather rides only these days.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by craneplaneguy » Jan 19 2018 12:17am

This entire thread reminds me why so many bike people have been also plane people (going WAY back....): lightness and strength, lots of both, in one package, is a pretty good trick and the discipline attracts a certain kind of person. If my plane had half the tech of a high end bike, it'd weigh a lot less, but they don't sell enough planes compared to bikes, so they are relatively low tech and expensive, I'm always amazed how cheap a high end bike is, considering how trick they are.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Buk___ » Jan 19 2018 12:33am

liveforphysics wrote:
Jan 18 2018 3:28pm

Even on my road bike, I look for the biggest sets of stairs to drop or climb, and ride over log piles and aggressive downhill trails,...
For that reason my roadbike is cromoly, and the frame has not yet broken...
After some more thinking and verifying.

Whilst those drops and jumps are almost certainly fatiguing your steel frame -- ie. slowly reducing its yield strength -- your peddle strokes and road chatter (and bodysway and breaking and accelerating...) are not.

On an Al frame *all* of them would be continually reducing the yield strength.

Once the yield strength drops far enough, the bigger impacts start to permanently deform the frame. That creates new stress risers, in the form of kinks and ripples in exactly the highest stressed areas, and failure occurs shortly after.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Chalo » Jan 19 2018 12:48am

And yet at the end of the day (quarter-century, to be accurate), the steel frames usually give up first. Go figure.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Buk___ » Jan 19 2018 1:15am

Chalo wrote:
Jan 19 2018 12:48am
And yet at the end of the day (quarter-century, to be accurate), the steel frames usually give up first. Go figure.
Nice anecdote!

Now provide some independent verifiable evidence?

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by MadRhino » Jan 19 2018 1:59am

craneplaneguy wrote:
Jan 19 2018 12:17am
This entire thread reminds me why so many bike people have been also plane people (going WAY back....):
Way back, before planes and bikes. Riding and flying are the same in ancient languages, and it was a tradition to give bird names to the best horses.
Make it fool-proof, and I will make a better fool.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Epyon » Jan 19 2018 2:10am

craneplaneguy wrote:
Jan 19 2018 12:17am
I'm always amazed how cheap a high end bike is, considering how trick they are.
Cheap?! I wish. I just dropped $4500 on a frame & shock. I spent much less on the car I drive most. :lol:
Although, compared to an airplane, I guess that would be cheap.

How did this thread balloon to 4 pages already?

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by MadRhino » Jan 19 2018 2:50am

Epyon wrote:
Jan 19 2018 2:10am
craneplaneguy wrote:
Jan 19 2018 12:17am
I'm always amazed how cheap a high end bike is, considering how trick they are.
Cheap?! I wish. I just dropped $4500 on a frame & shock. I spent much less on the car I drive most. :lol:
Although, compared to an airplane, I guess that would be cheap.

How did this thread balloon to 4 pages already?
Let me guess. That is what they asked me for the 2018 V10 carbon... Too much IMO. My MK1 will ride another year.

The thread got long with side discussion about frame material, steel vs alu
Make it fool-proof, and I will make a better fool.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by liveforphysics » Jan 19 2018 4:18am

MadRhino wrote:
Jan 18 2018 8:02pm
Cyclo cross had gained a lot in popularity here, since I quit about 10 years ago. It is a very tough disciplin. Courses are designed to push participants to their limits of strength and aerobics. I was too old to be competitive, but had a lot of fun trying.

I was riding a Specialized Tri-Cross Expert double, alu-carbon. I guess that most are carbon today, and your steel frame must be one among very few in the races.

In DH too, carbon frames are taking over, about half of them right now. The other half are alu. Trying to find a steel DH frame, one would need to look at 20 yr old bikes.
We obviously need to ride together my friend. It would be an honor and pleasure for me. You're right that almost everything else there is carbon with just a couple other steel bikes. Cyclocross is 98% rider and 2% bike, so I use steel just because I crash a ton and carbon frames don't like to tumble through rock gardens as much as steel. I've been riding more mellow-ish as my broken back is still recovering and randomly likes to spasm and drop me if I get too wild.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by MadRhino » Jan 19 2018 6:47am

Sure we should ride, especially since I’d love to ride the long trails in your area. We’ve missed one occasion last summer, but here you would have found the mountains ridiculously small. Although some trails are very challenging, the courses are repetitive.

I chose the Tricross because its top tube is wide and flattened, sitting so comfortably on the shoulder. Now the son of my friend has it and enjoys it as much as I did. Here cyclo cross got added to cross fit training, that is very popular now. Too aerobic for me.

I ride only DH bikes now, heavier but comfortable on the rough. I don’t do much crank work anymore but with power, I have found a new fun in uphill jumps. :D
Make it fool-proof, and I will make a better fool.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by speedmd » Jan 19 2018 11:33am

MadRhino wrote:
Jan 19 2018 1:59am
craneplaneguy wrote:
Jan 19 2018 12:17am
This entire thread reminds me why so many bike people have been also plane people (going WAY back....):
Way back, before planes and bikes. Riding and flying are the same in ancient languages, and it was a tradition to give bird names to the best horses.
Interesting derivation in the language. I always thought of flying along while in brief contact with the ground as much more interesting and exciting than flying up in a plane. 8)

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by e-beach » Jan 19 2018 6:02pm

So for $65.00 I picked up a used Trek 4500.
used trek.JPG
used trek.JPG (214.13 KiB) Viewed 1130 times
It came with some extra welding......They must have learned something somewhere.
Renforcment.JPG
Renforcment.JPG (118.38 KiB) Viewed 1130 times
At 21 inches it is really 1 inch too long for my stumpy legs,......
21inch.JPG
21inch.JPG (87.24 KiB) Viewed 1130 times
but it has a huge triangle to put my battery. Didn't take long to swap some parts and now I have a safe peddle bike. 8)
Full Trek.JPG
Full Trek.JPG (165.88 KiB) Viewed 1130 times
The rest of the work will go on starting this weekend. If I push it, might only a take a few days.

@Speedmd: After giving it a good think, I have decided to retire the old Liahana frame. I agree, it served it's purpose and gave me many miles of dependable riding.

@LFP: Thanks for the offer of rapping my frame, but after looking around I now see I can get a cheap peddle bike around here for $65 or less. If I look around maybe $35.00. Besides, some of the parts from the Trek don't swap well to the old bike so I guess it is going to the big recycle bin in the sky, or where ever it gets hauled to by the city. We should get lunch together before you leave town.

So, I will be pulling parts off the old frame, use what I need or can. If possible, sell some parts for a reduction in overall cost of a new bike, and/or donate some parts to the Bikerowave, which is a very-cool coop bike shop in my city. I am all for keeping them going.

Thanks all for the posts.

:D
Favorite Quote: "This is L.A., sugar. There is no 'over the top." --- Chris Erskine

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Previous Build:1992 Trek Antelope 800 - Bone Crusher (no suspension) - Yescomusa 800 watt 36 volt front wheel kit. Don't do it! Get suspension!!!

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by craneplaneguy » Jan 20 2018 10:42am

speedmd wrote:
Jan 19 2018 11:33am
MadRhino wrote:
Jan 19 2018 1:59am
craneplaneguy wrote:
Jan 19 2018 12:17am
This entire thread reminds me why so many bike people have been also plane people (going WAY back....):
Way back, before planes and bikes. Riding and flying are the same in ancient languages, and it was a tradition to give bird names to the best horses.
Interesting derivation in the language. I always thought of flying along while in brief contact with the ground as much more interesting and exciting than flying up in a plane. 8)
Flying real low in a light airplane, like fence post height, nape of the earth, terrain following, is the crack cocaine of flying. Super fun, addictive, and obviously can be hazardous. Did I say it's REALLY fun?

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by speedmd » Jan 20 2018 11:30pm

After giving it a good think, I have decided to retire the old Liahana frame. I agree, it served it's purpose and gave me many miles of dependable riding.
Glad you found a good older frame at a reasonable price. Big Name brand also. Nice space for batteries. Like the added plate where your old one broke. With some good brake pads it should be a long lasting safe ride.
Flying real low in a light airplane, like fence post height, nape of the earth, terrain following, is the crack cocaine of flying. Super fun, addictive, and obviously can be hazardous. Did I say it's REALLY fun?
:shock: :twisted:

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by 2old » Jan 21 2018 12:00pm

Can the casting tape be used to repair a chainstay crack (near the bottom bracket) in my friend's titanium frame?If it's as strong as indicated, should be a perfect fix.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by MadRhino » Jan 21 2018 12:34pm

2old wrote:
Jan 21 2018 12:00pm
Can the casting tape be used to repair a chainstay crack (near the bottom bracket) in my friend's titanium frame?If it's as strong as indicated, should be a perfect fix.
I don’t know the specs of a casting tape repair, but I know the risk of riding a fishtailing bike. Rear triangle lateral stiffness is the major safety requirement at high speed, because it can send you high side in a turn even if you had done everything right.

Titanium bikes need to be overbuilt on the rear, because of high flex factor of Ti. Because of its high flex though, Ti is not crack prone. Most Ti bike frames are sold with lifetime guarantee and even when they aren’t, manufacturers are usually willing to repair, so that is the first thing to check for.

Very few welding shops are equipped to repair a Ti bike frame, because Ti need to be welded in a gas chamber and those are usually too small. So casting tape may be a last solution, if the bike is not ridden fast.
Make it fool-proof, and I will make a better fool.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Chalo » Jan 21 2018 6:17pm

2old wrote:
Jan 21 2018 12:00pm
Can the casting tape be used to repair a chainstay crack (near the bottom bracket) in my friend's titanium frame?If it's as strong as indicated, should be a perfect fix.
I doubt the tape can be wrapped tight enough and thick enough to do the job right in that location. I'd only try that trick after having the thing welded first.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by liveforphysics » Jan 21 2018 7:09pm

2old wrote:
Jan 21 2018 12:00pm
Can the casting tape be used to repair a chainstay crack (near the bottom bracket) in my friend's titanium frame?If it's as strong as indicated, should be a perfect fix.
You could give it a shot. Get the surfaces sanded to be rough and cleaned with acetone, and if you can get the right amount of snug wrappings into the area it might work out fine.
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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by 2old » Jan 22 2018 12:26am

Thanks for the help; can't hurt to try.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by Chalo » Jan 22 2018 12:39am

2old wrote:
Jan 22 2018 12:26am
Thanks for the help; can't hurt to try.
For what it's worth, titanium requires no heat treatment and a well-done welded repair should be good as new. Lashing fiber and resin on there will make later welding extremely difficult, though.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: Potential Catastrophic Frame Failer Averted ….sort of.

Post by MadRhino » Jan 22 2018 1:27am

Chalo wrote:
Jan 22 2018 12:39am
2old wrote:
Jan 22 2018 12:26am
Thanks for the help; can't hurt to try.
For what it's worth, titanium requires no heat treatment and a well-done welded repair should be good as new. Lashing fiber and resin on there will make later welding extremely difficult, though.
I can’t see why. I mean, Ti can be heated high temp without damage, turning any resin leftovers to ashes. It could be sandblasted with many powder types without any wear, even acid cleaned before welding if needed. So I believe that any temporary repair that is not physically damaging the tubing, can be cleaned easily before welding.
Make it fool-proof, and I will make a better fool.
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