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Discussion Starter #1 (Edited)
Some time ago I replaced my OEM foot pegs with LSL or DCC or some other aftermarket, but it was a direct bolt on 5 minute job. I even saved my ball bearings from the OEM pegs. Is there a direct bolt on lowering bracket that will accept the equivalent of an OEM peg? ('13 Bonneville). As I search the Web is seems like the brackets are specific to the bracket maker's brand of peg. I just want to bolt on some brackets and bolt my pegs to the brackets, put the Lock-Tite away and be done. Thanks MBW
 

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Note that the oem bonneville pegs have a long history of failing at the casting and also at the bracket welded head bolt. You should go with an aftermarket peg and upgrade the bracket by knocking out hte weld bolt, re-drilling to next size up and use a shanked bolt with nylock nut. Having a peg fail while riding along is a really bad day indeed.

I went with SW-Motech bear-trap style pegs for bonneville. These have two mounting positions and can be set about 1" lower than stock. They also look the part for our bikes, not to modern like. They fit the oem bracket.
 

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Note that the oem bonneville pegs have a long history of failing at the casting and also at the bracket welded head bolt. You should go with an aftermarket peg and upgrade the bracket by knocking out hte weld bolt, re-drilling to next size up and use a shanked bolt with nylock nut. Having a peg fail while riding along is a really bad day indeed.
The foot pegs that have fractured and reported in this forum had a history of either being loose or damaged from a tip over or low speed accident. Photos of the fracture surface usually showed a fatigue fracture that occurs over time.

This joint is a tension joint that is designed to absorb bending and shear loads by the mating surfaces, not the bolt. If the bolt is not torqued to the design spec, the bolt can be subjected to bending and shear. A tip over could cause the bolt to loosen due to over load or cause a small crack at the root of bolt throat. Word to the wise, check the torque of the foot peg bolt particularly after a tip over or accident.

Drilling the bracket to accept a stronger bolt weakens the bracket (probably not a problem) and increases the strength of this joint. However, after this modification a tip over or accident would transfer more load to the frame potentially causing damage to the frame. In other words, the foot peg assembly could be considered a sacrificial weak link. One would ask: Would you rather have a broken foot peg assembly or a bent frame?

Should one decide to drill the bracket to accept a larger diameter bolt, make sure that the hole is oversized (as the factory original bracket) so that the shank of the bolt does not touch the surface of the hole. This is done so the the bolt does not see bending or shear loads. Bending and shear loads are born by the contact surfaces of the brackets due to the clamping force of the properly torqued bolt.
 

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I also fitted SW Motech pegs in the lower position.For me this is a great improvement over the standard set up as im 6ft.It gives just that little bit more room.
 

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The foot pegs that have fractured and reported in this forum had a history of either being loose or damaged from a tip over or low speed accident. Photos of the fracture surface usually showed a fatigue fracture that occurs over time.

This joint is a tension joint that is designed to absorb bending and shear loads by the mating surfaces, not the bolt. If the bolt is not torqued to the design spec, the bolt can be subjected to bending and shear. A tip over could cause the bolt to loosen due to over load or cause a small crack at the root of bolt throat. Word to the wise, check the torque of the foot peg bolt particularly after a tip over or accident.

Drilling the bracket to accept a stronger bolt weakens the bracket (probably not a problem) and increases the strength of this joint. However, after this modification a tip over or accident would transfer more load to the frame potentially causing damage to the frame. In other words, the foot peg assembly could be considered a sacrificial weak link. One would ask: Would you rather have a broken foot peg assembly or a bent frame?

Should one decide to drill the bracket to accept a larger diameter bolt, make sure that the hole is oversized (as the factory original bracket) so that the shank of the bolt does not touch the surface of the hole. This is done so the the bolt does not see bending or shear loads. Bending and shear loads are born by the contact surfaces of the brackets due to the clamping force of the properly torqued bolt.
Buddy of mine had his Bonne peg fail at the bolt on a bike with only 7500 miles on it. New replacement peg, installed by Triumph dealer, failed again within 500 miles, at the same bolt shearing point. He states he never stood on the peg. That's a design flaw. He counts himself luck to not have been injured in these two events.

Your concerns over "stressing" the frame in a tip over are silly. The Scrambler has a much more robust foot peg setup than the bonneville and we don't hear of frame damage when they tip over.
 

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Buddy of mine had his Bonne peg fail at the bolt on a bike with only 7500 miles on it. New replacement peg, installed by Triumph dealer, failed again within 500 miles, at the same bolt shearing point. He states he never stood on the peg. That's a design flaw. He counts himself luck to not have been injured in these two events.

Your concerns over "stressing" the frame in a tip over are silly. The Scrambler has a much more robust foot peg setup than the bonneville and we don't hear of frame damage when they tip over.
Do you think that hitting a curb or a moving accident with an over-strengthened foot peg might bend the frame? How do you know beyond your speculation, opinion, or conjecture?

Did your buddy buy his bike new and did he ever tip his bike over or hit a curb with his foot peg? How about a previous owner? Is it possible that the dealer mechanic damaged the foot peg by over torquing the bolt?

Design flaw? Possible, but highly unlikely. You haven’t considered a perfectly good design that was not manufactured or assembled correctly could be the cause. If you want to convincingly advance the idea of a design flaw you need to do the following:

Collect history of failed foot pegs.

Gather photo documentation of the fractured part with measurements.

Determine what testing should be done and protocol for analysis of the testing.

Include nondestructive testing like dye penetrant, X-ray, or ultrasonic to find crack-like discontinuities.

Perform visual and macroscopic examination of the fracture surface.

Have an electron microscope examination performed of the fracture surface to determine the fracture mode.

Perform metallurgical examination of etched and un-etched mounted samples of the fractured part to delineate the microstructure.

Have a chemical analysis done to determine the chemical make up of the fractured part.

Have mechanical testing done to determine the mechanical properties of the part like strength, elastic modulus, and elongation at the fracture point.

Have testing done on other non fractured parts to compare with the fractured parts.

An engineering and analysis report should be written that discusses failure mode, formation of inclusions and recommendations for design or manufacturing improvements.

You might want to get busy. There is a lot to do before a convincing case can be made that there is a design flaw in these foot pegs.
 
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