How to ruin a perfectly good stock frame

[Krunk_Kracker]

You wanna know the fastest way to kill a forum?

Have cranky old members who do not know how to respect other people and offer positive criticism.

Chasing off members is counter-productive to what a forum is.

 

[oohsam]

Krunk - You're spot on. I'm tellin you, I've had ppl on other sites say "dont post ur build on GSR...you'll just get a flaming, unless ur restoring"

Also, The guy hadn't even finished his frame...how'd ya know it was done! What if it was going to be so over engineered its too strong! lol...
I'm just sayin.

Peace

 

[tkent02]

If he leaves or if he dies on that piece of junk, the result in membership in the forum is the same.
Just a little rougher way to adjust the numbers.

Can you guys honestly say you didn't see any structural difficulties with that frame?
You really would hop right on it and go down a normal road at a normal speed?

 

[oohsam]

If he leaves or if he dies on that piece of junk, the result in membership in the forum is the same.
Just a little rougher way to adjust the numbers.

Can you guys honestly say you didn't see any structural difficulties with that frame?
You really would hop right on it and go down a normal road at a normal speed?

Thats a pretty lousy thing to say man. In-fact, its beyond lousy...

I didn't say any structural difficulties with it, no. Mainly because he hadn't even finished it.

You dont know if he was just going to make it a show bike to put in his shop, or make it a promo bike, or a concept, or god knows what else.
Ya just assumed he'd be taking up the mountains doing 150k's round the twists....
Different things are built for different purposes. If this was built for a certain purpose, then who cares how much reinforcement it has.

Also. I'm not an engineer. I dont know the first thing about structural integrity of a frame. However, this guy is an engineer. I have about 10 mates who are engineers, and if I know one thing, they all over engineer everything due to their amazing knowledge......

Ya really shouldn't judge so early in the piece...

 

[Mindless]

Krunk - You're spot on. I'm tellin you, I've had ppl on other sites say "dont post ur build on GSR...you'll just get a flaming, unless ur restoring"

Also, The guy hadn't even finished his frame...how'd ya know it was done! What if it was going to be so over engineered its too strong! lol...
I'm just sayin.

Peace

This isn't about bashing the new guy because he's building a hardtailed GS. A GS450 isn't a super loved bike so why not customize it to make it better and unique? I'm all for builds like this, but if it's against better judgment,?you bet your ass someone is gonna step in and tell him "You know what, that's probably not a good idea." or "You'll get yourself killed if you don't fix that.". Enough people get killed in traffic already.

As I said, it doesn't take a rocket scientist to figure out when something is poorly constructed. Any serious frame modifications need a proper jig to ensure everything is in line, and I see nothing worth calling a jig anywhere near that bike.

Also. I'm not an engineer. I dont know the first thing about structural integrity of a frame. However, this guy is an engineer. I have about 10 mates who are engineers, and if I know one thing, they all over engineer everything due to their amazing knowledge......

Then let me tell you this: Nothing in the pictures posted is over-engineered. I can't even spot a properly notched tube (which is basic frame building 101) and then it's been roughly MIG-welded together and had it's welds ground down. If you want to extend or change the bend of a tube midway you need to make slip joints and stuff which gives the tube strength where the weld is. There's nothing of that here.

To me, it seems like this was thrown together on a hot afternoon using an angle grinder.

 

[Agemax]

If he leaves or if he dies on that piece of junk, the result in membership in the forum is the same.
Just a little rougher way to adjust the numbers.

Can you guys honestly say you didn't see any structural difficulties with that frame?
You really would hop right on it and go down a normal road at a normal speed?

if you take the time to read it properly, he hasnt actually finished it yet, so hold your judgement until the finished frame is on show

 

[oohsam]

This isn't about bashing the new guy because he's building a hardtailed GS. A GS450 is a P.O.S bike so why not customize it to make it better and unique? I'm all for builds like this but if it's against better judgment, you bet your ass someone is gonna step in and tell him "You know what, that's probably not a good idea." or "You'll get yourself killed if you don't fix that.".

As I said, it doesn't take a rocket scientist to figure out when something is poorly constructed. Any serious frame modifications need a proper jig to ensure everything is in line, and I see nothing worth calling a jig anywhere near that bike.

Yeah, but ya hand't let him finish to see what he'd come up with!

 

[oohsam]

Great Minds Agemax. LoL.

 

[Baatfam]

Advice is one thing, Pointing the finger, jumping up and down and yelling "you're doing it wrong" isn't cool.

I saw no jumping up and down or yelling in what I read...just concern...
A sharing of opinions for the common good, if you will...

Yes, some posters did feel he "was doing it wrong" and spoke up...this is a form of "advice"...
The OP can take this advice or not, but there is nothing wrong with people giving it...

Seems to be some oversensitivity going on....

 

[tkent02]

NO, he said it didn't need any more, that it was already strong enough, and he certainly didn't mention that it wouldn't be ridden, only looked at.
Hopefully it gets a few more improvements.

 

[Baatfam]

I have about 10 mates who are engineers, and if I know one thing, they all over engineer everything due to their amazing knowledge......

We must know different engineers....

 

[oohsam]

I saw no jumping up and down or yelling in what I read...just concern...
A sharing of opinions for the common good, if you will...

Yes, some posters did feel he "was doing it wrong" and spoke up...this is a form of "advice"...
The OP can take this advice or not, but there is nothing wrong with people giving it...

Seems to be some oversensitivity going on....

Ahhh....When you tell someone their build is Junk, or Rubbish, or Stupid.....

That aint advice.....Advice would be more along the lines of

"I see what you're doing, have you considered the following...."

Its just respect really. I didn't see alot of that goin on...Lots of disrespect though.

 

[oohsam]

We must know different engineers....

hahahah...One of my mates is an aerospace engineer....
Wowzer. Every time he comes over he's like, "you might wanna weld something there"...When I ask why I get some sort of explanation that has something to do with torque transfer, Shock absorption and how the wright brothers made their plane take off...

Now i just shutup and weld.

 

[mlc216]

I'm not gone, I'm just not going to argue anymore.

The frame is not done... it will get a seatpost and a few gussets.

The neck to frame attachment alone is good for over 35,000 lbs in shear. For a 300 lb bike with a 200 lb rider that seems to be plenty strong. If I can find some freetime this week I'll draw it up in 3D and do a little FEA for you so you guys can sleep at night.

As for the springer... it's something I've had for a while and I wanted to see just how long it was. Only posted the picture with it on there because the pot was already stirred. I've got a set of 35mm xs650 forks that are slightly longer than my stock GS forks that I'll be adapting to fit. I'll save the springer for a later build.

Thanks to all who support something different, it's nice to know not everyone hates my "frame".

 

[afholderman]

Honestly re-read this from the beginning. Nessism was quite polite in his suggestion that more bracing would be needed. The OP then went off talking about how he would remove his trash from the board and even in a slant at Nessism's stable just for good measure. When you come in with an attitude that everyone is against you, people are going to end up against you.

 

[mlc216]

As I said, it doesn't take a rocket scientist to figure out when something is poorly constructed. Any serious frame modifications need a proper jig to ensure everything is in line, and I see nothing worth calling a jig anywhere near that bike.

A frame built with a jig is only as straight as the jig. I'm building ONE frame, and a jig is NOT needed to build a frame straight. A level, tape, and plum bob are plenty enough to build anything you want straight. Even the best jig cannot hold a frame perfectly straight if it's not welded in an manner that promotes even heating. When welds are thought out and planned appropriately, a fabricator can pull metal one way or another as desired. Basically I used the frame as a jig. I braced around areas I wanted to stay put and cut and extended other areas using the existing triangle to create the geometry I wanted.

Then let me tell you this: Nothing in the pictures posted is over-engineered. I can't even spot a properly notched tube (which is basic frame building 101) and then it's been roughly MIG-welded together and had it's welds ground down. If you want to extend or change the bend of a tube midway you need to make slip joints and stuff which gives the tube strength where the weld is. There's nothing of that here.

To me, it seems like this was thrown together on a hot afternoon using an angle grinder.

I don't have a "tubing notcher", but I do know how to properly notch or cope tubing. All of my tubing was test fit multiple times to assure proper fitment before it was welded. The only place I needed to extend or change the bend of tubes was on the lower frame rail connections front and rear. I created a slip joint up front and lugged, plug welded, beveled the tubing, and then did a full penetration weld on the rear joints. Both of these connections are strong, but I will add a triangular gusset on the front joints and add some extra bracing on the inside of the frame rails on the rear connections.

I took my time because I enjoy metalwork and I want a strong frame. This was not just thrown together... maybe my crappy cell phone pictures have given the wrong impression.

 

[mlc216]

Honestly re-read this from the beginning. Nessism was quite polite in his suggestion that more bracing would be needed. The OP then went off talking about how he would remove his trash from the board and even in a slant at Nessism's stable just for good measure. When you come in with an attitude that everyone is against you, people are going to end up against you.

I apologize for coming in with a negative attitude. I shouldn't have responded how I did originally. I will continue to post progress and answer as many questions as I can, and I'll do it without any negativity.

 

[Krunk_Kracker]

I have no idea from a structural point whether or not his frame is good.

I'm just commenting on the trend that anything done that isn't OEM is usually poo-poo'ed on this forum.

 

[Nessism]

The frame is not done... it will get a seatpost and a few gussets.

The neck to frame attachment alone is good for over 35,000 lbs in shear. For a 300 lb bike with a 200 lb rider that seems to be plenty strong. If I can find some freetime this week I'll draw it up in 3D and do a little FEA for you so you guys can sleep at night.

Shear strength is one thing, but there are other important design considerations for a motorcycle frame too, such as torsional and lateral rigidity of the front end so the frame is not unstable at speed when upset by road inputs. I suggest you run some moment of inertia calculations on the torsional and lateral stiffness of your design, particularly the front end, and compare to a stock 450 frame as a reference. This frame is clearly designed to flex in a vertical plane, which may be okay for a ridged frame, but a torsionally flexy front end with make the bike prone to possible tank slappers.

 

[mlc216]

it's been roughly MIG-welded together and had it's welds ground down...

Also, I've not ground down any welds...