Reenforcing down tube?

I was looking at some JB weld epoxy kits that looked interesting but I don't know if they would work. I've been researching repairing the frame and the majority of findings have been to scrap the aluminum frame. Regardless I will continue to ride it (10 or so miles with my fingers crossed) until my new bicycle comes. It is the same frame (almost) and brand (Raleigh Venture 3.0 only this time it's a steel frame - if you're interested you can see it here "http://www.raleighusa.com/bikes/comfort/venture-3-0-12/"). I like the comfort design because of the spring loaded seat post and large comfortable seat and frame design however it appears as though the angle (pic attached) looks less favorable but I'll see if I can make it work. I'll have rear brakes and gears again too.

"Break it in to ride it and ride it 'til it's broken."
 

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Jeff, do yourself a favor, there is no "weld" in JB, it's just marketing for epoxy. Also, I'd be negligent if I didn't say after looking at the pics you posted on the cracked frame you're really pushing it. Not being snarky but that's serious and I wouldn't ride it. Be careful.

I not sure what series alloy it is, some takes tig welding better than others, but as others have said upthread, aluminum needs re-heat treating after welding.

On the original subject, I recommend to NEVER drill frames, regardless if they are steel or alloy.
 
Jeff, do yourself a favor, there is no "weld" in JB, it's just marketing for epoxy. Also, I'd be negligent if I didn't say after looking at the pics you posted on the cracked frame you're really pushing it. Not being snarky but that's serious and I wouldn't ride it. Be careful.

I not sure what series alloy it is, some takes tig welding better than others, but as others have said upthread, aluminum needs re-heat treating after welding.

On the original subject, I recommend to NEVER drill frames, regardless if they are steel or alloy.

I originally had my first motor put on by someone else (1/2010) and he drilled holes in the top tube and where the chain tensioner attached. I will NOT be drilling any holes in my new steel frame and with my increased understanding with all the variables involved with these motors I imagine I should have greater success with my future builds. Thanks for the helpful advise to all of you guys.
 
appears as though the angle (pic attached) looks less favorable but I'll see if I can make it work. I'll have rear brakes and gears again too. "Break it in to ride it and ride it 'til it's broken."

A custom mount will be needed. The ideal "V" is 75 degrees. You have a number of options.

As far as JB Weld, it has VERY few applications on these bikes, the frame NOT being one. You might as well use tape.
 
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Crack and Mounting UPDATE!

Hello fellow mtbers. Before my ride I took the bolt that goes into the threaded hole where the crack is and applied super glue to the threads and tightened it down (pic attached). That should help keep the two parts from cracking as fast. I made it five and a half miles with the crack in my frame before being brave (some may call stupid) and deciding to go 27mph after going the first five miles at 18mph. My left threaded rod snapped at the same place they always do right behind the front tube bracket. The mounting stud on the right is still going strong after 98 miles. Again, since I placed a nut close to the engine the bolt also snapped off inside the threads of the nut leaving enough exposed to just unscrew with some vise grips. I picked up a 6mm x 55mm (2.165") Grade 5 (8.8) bolt from the plACE. I didn't even have to take the motor off to replace the bolt. I slapped it back together and went home (six miles). I kept it at 18mph the entire ride. I plan on remounting the engine using two front mounts on either side of the crack so when it does finally give it will be held together by the mounts. I will be securing the rear mount first as suggested by everyone on this forum making sure that it is parallel to the seat tube. I will then adjust the angles of the u-bolts to accommodate the angle of the front engine mount. If all goes well than I should be able to get some more miles out of this frame until my new bicycle arrives. Wish me luck fellas!
 

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Mounting UPDATE!

All of your well wishes have paid off immensely...Thank you, MBers. After setting a favorable position (7/16" top, 15/32" bottom from tube) for the rear mount I was able to finagle the two large (1 5/8" x 5/16) front mount brackets (sickbikepartsdotcom). As you can see from the photos the angle of the u-bolts had to be altered from a perpendicular (90° angle) to whatever angle they are in these pics in order to accommodate the rear mounting position. As with any remounting (unless you have welded mounts) the position throws off the entire chain length which in turn throws off the entire drive train. (a spring chain tensioner probably alleviates more readjustment then the stock tensioner). I also replaced all my tensioner bolts (4) with grade 8 (10.9) hex bolts and my tensioner wheel bolt with a 1/2" hex bolt so I can actually torque the wheel down properly (pic attached). I will now be riding blue lightning as blue flicker as her flame is almost out. The crack in the frame hasn't worsened so I can only hope (since it's worked so well for us) that my new mounting job will hold the frame together just a little bit longer. Let me know what you think fellow MBers.
 

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Crack & Mounting UPDATE TOO

All of your well wishes have paid off immensely...Thank you, MBers. After setting a favorable position (7/16" top, 15/32" bottom from tube) for the rear mount I was able to finagle the two large (1 5/8" x 5/16) front mount brackets (sickbikepartsdotcom). As you can see from the photos the angle of the u-bolts had to be altered from a perpendicular (90° angle) to whatever angle they are in these pics in order to accommodate the rear mounting position. As with any remounting (unless you have welded mounts) the position throws off the entire chain length which in turn throws off the entire drive train. (a spring chain tensioner probably alleviates more readjustment then the stock tensioner). I also replaced all my tensioner bolts (4) with grade 8 (10.9) hex bolts and my tensioner wheel bolt with a 1/2" hex bolt so I can actually torque the wheel down properly (pic attached). I will now be riding blue lightning as blue flicker as her flame is almost out. The crack in the frame hasn't worsened so I can only hope (since it's worked so well for us) that my new mounting job will hold the frame together just a little bit longer. Let me know what you think fellow MBers.

Obviously not a whole lot of thinkers out there...just doers. :D Anywho,

I inspect the crack thoroughly before each ride and don't ride over six miles at a time.

84 miles ridden with the crack (Max speed 29.4mph, Avg. speed 15.9 [computer readout]), (Cruising speed 18-20mph)

62 of those miles are on the new mounting job.

The new bicycle (18") didn't measure up so I left it at the store and ordered the 20". It looked like the tubes were a little smaller all around but that could just be the darker color giving it that appearance.

Tip O' the Day - I used super glue to stop a seep in my gas tank. :D
 
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150 miles with a crack in the tube. Chain tension is ready for no more tensioner. Just picked up the new bike also. Luck O' the Irish!

Happy St. Patrick's Day!
 

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