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I've been seeing more and more sketchy fabrication popping up so I thought i'd try and pass on some hard learned tips and observations. I'll skip over the obvious topic of the need for proper welding of any modification and focus instead on sound engineering design.

Motorcycles are subjected to some pretty extreme forces during riding from acceleration, braking, rough roads and unexpected course corrections etc. Add the weight of plus size riders and or passengers and things get even more critical.

Whenever a bike is modified either with bolt on parts or custom fabbed ones you need to make sure they will still take the strain nescessary for a safe ride. Footpegs should be strong enough to survive the strongest repeated kicking and bouncing you can deliver. I'm talking about jumping up and down on them with all the force you can muster. If they don't bend or break you are good to go.

The same goes for brake pedals, brake linkage, handlebars, passenger pegs, sissy bars, caliper mounts, fenders etc. If you can bust it off with your bare hands sitting in the driveway you don't need to be trusting your life to it on the road.

Be sure to use adequate hardware too. Use grade 8 on anything critical. Put loctite on everything. Make damn sure that sissybar/rear fender connection will take any strain it will ever see.

What it all boils down to is common sense and attention to details and safety. If you live as long as I have building and riding bikes you can hop up on your own soap box and try to pass something on to the next batch of youngin's :)

Of course if you choose to ignore this sage advice that's OK too. It will just provide a cheap source of used parts for the rest of us ;)
 

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Great advice and may I add another part that needs to be well built, the kick stand, especially if you have a kick start bike. Often over looked and whilst unlikely to end in tragedy can end up in pain and a damaged bike - you can guess how I know.
 

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Great advice and may I add another part that needs to be well built, the kick stand, especially if you have a kick start bike. Often over looked and whilst unlikely to end in tragedy can end up in pain and a damaged bike - you can guess how I know.
my shovel was laying on it's side, in front of a ******* bar at 2am. Broke up a custom made belt guard, and old timer had given me...
 

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This is fantastic advise that MUST be followed. Do not worry about whipping something up in a month. It might take a few years. Due to personal health reasons my never ending Triumph project is slow moving and I indend to keep it that way. It's my life and I have a beautiful family that I do not want to leave behind. I weld and weld till I feel it can handle one hell of a ride. Thanks for posting this thread LILBILL...
 

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Several years ago i decided it was time to build a bike, I sold off my perfectly good running 800 Vulcan and bought a shovel bottom end, founds some heads on ebay, as well as an 18" over DNA springer and a frame. Like I said it was my first build and I had some serious rooky buying and building mistakes. My biggest building mistake was my brake linkage for my only brake, the rear one. It really sucks when you lose a head light on your way home at dusk, only to find out that you brake linkage fell apart as well, thank god we dont have hardly any traffic here in BFE. Second big mistake was reworking and rebuilding the junk homemade frame I scored. The down tube broke in half on me at 60mph, I still dont know how I didnt go down, but I did manage to aim it a road ditch where the mud in the bottom stopped me abruptly. That bike tought me some pretty good lessons in bike building, if your not sure it will work, it wont! Since that bike I have done a couple more, I am still on a learning curve, but I definately dont take any chances with structural integrity of the things that have to have it.
 

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And I'll add . . .

Learn how to use fasteners correctly. That means correct screw/bolt, flat washer to spread the load and either a cut washer & standard nut or a locknut (nylon or deformed thread).

I see so many bikes put together with nuts cutting into metal or barely holding on.

Another is routing of electrical wires and plumbing. Put them where they're not gonna take abuse or get in the way. Secure them to frames & brackets. Use sheathing if in a high-traffic area where they'll get abraided. Keep them out of the way of regular service areas where they'll get pulled on or crushed.

Jason
 

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Lilbill,
Thanks for this thread, it should be made a sticky or at least a "tech".
I see so many new guys get into a hurry to get a project done that they will cobble it and then when it breaks down, wanna cuss the bike?

Theres a coupla things that I'd like to add to this thread;
1, If your buying a basket or used bike and you don't know the history on it, or if your not familure with motorcycles, pull it apart as far as you can and inspect the inner workings. You will get two things from this, a- a working understanding of what does what/why and b- you can see for yourself if anything is gettin ready to let go and be able to replace it before it takes out something else. Take your time and put it back right and you will have miles of trouble free riding.

2, do not run cobbled up/sketchy wiring. Some people get intemadated when it comes to wireing, decide if you have the ability to do it (it realy isn't that hard if you work on one circuit at a time) and if not, spend the coin to have it done right.
 

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"Learn how to use fasteners correctly. That means correct screw/bolt, flat washer to spread the load and either a cut washer & standard nut or a locknut (nylon or deformed thread). "
good advice as usual, jason...let me just add this, grade 8 [chicom] aint always grade 8 in the free world!
KNOW THINE BOLT!
had an old machinist question my choice of motor mount bolts on a stretched/rigid triumph project, he swore that the bolts i picked were TOO hard! showed me with a good sharp centerpunch and a small hammer, the difference in the size of a punchmark that would be left in my bolts and the stock Triumph bolts [that wouldnt fit] the punch left a larger mark on the stock bolts......my cool grade 8 bolts soon "sang" themselves in two on a long run at seat buzzing RPM! looked as if a laser had cut them in two!
bolts that can stretch will resist vibration tons better than superhard bolts that resist any stretch or bending
i only post this after hearing some wanker tell me that he was`nt worried cause he was using ALL stainless bolts from the local hardware store! i told him that while that grade stainless might resist corrosion ok, unless you bought them from aircraft spruce or someplace similar, your probably buying grade 3 bolts....NOPE! stainless bolts are best! he had heard some mega=builder on TV say so!
 

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Quick addition to the Grade 8 bolt part...they are generally intended for use where you have linear forces, IE inline with the shank of the bolt. They can often be too brittle to take shearing loads and that's where you want a Grade 5 (typically.)

Like kllrjo says, know thine bolt. I think EVERY shop, home or pro, should have a bolt torque and stress load chart. Saves questions and once you look at it enough you will be able to recognize the proper bolts more easily.
 

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You see a pattern here? So many of the replies concern fasteners and the importance of considering the seperate components as parts of a system. It seems that a strange sort of ignorance surrounds the "simple?" act of bolting shit together! I've been a witness to seeing all sorts of parts fall or fly off moving motorcycles over the years. Sometimes with disasterous effect.

Regards,
Geo.
 

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My first Harley,in 1974, was a 68 xlch that the previous owner added a weld on hardtail,raked neck,and stretched the front downtubes 4".He was a supposed "bike builder" with a good reputation.Well the hardtail and neck was ok but the downtubes were butt welded with no slugs in them.It was a typical 70's style bike with an 18" over springer.As you might have guessed the damn cradle broke out of the frame.I had just slowed down from a 90 mph ride with a buddy of mine when it started vibrating like crazy.I was on an exit ramp when it let go.The only thing keeping the frame from hitting the ground was the top motor mount holding onto the backbone.Man you talk about an ass puckering experience!!I shitcanned that frame and bought a Jammer rigid and 6" over springer. Frame work has to be right,it could cost you your life!!
 
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