350x Frame Material Specs

[wonderboy]

I'm looking for the specifics of the 350x frame such as metal composition (i.e. chrome moly) and wall thickness. Has anyone dissected and analyzed these frames? I'm curious to do some analysis of the stresses in the frame. I can get all the dimensions that are measureable from the outside, but can't determine wall thickness non-destructively. And I'm assuming these frames are NOT a chrome moly steel, but I really don't know. Thanks!

[Billy Golightly]

Not chromoly from everything I've ever heard. Wall thickness is probably about 1.5mm or around .065 is my estimation from the ones I've cut into...

[Flyingw]

My guess Frank is the frames are made from run of the mill mild steel.

[wonderboy]

Thanks for the info guys! I'm not sure if I'll come up with anything useful, but if I do I'll post my results. I'm trying to do some FEA analysis of the frame to determine the optimal gusset size and locations. I know there are a lot of practical solutions that work (based on experience and trial-and-error), but I'm just really curious how much gusseting is actually required, what locations benefit, and how large they should be. If I fail horribly at all this, I'll just revert back to doing what everyone else does (highly likely!).

Thanks guys. If anyone has additional spec info, or has a frame already destroyed and doesn't mind grabbing the calipers and measuring the wall thickness of the various sections, I would be ever appreciative! For now, I'll run with what I've got.

[jays375]

What you have seen gusseted is what works.Have you rode a 350x with a gusseted frame?It is a whole different machine.Better off doing it completely from the start.You won't be dissatisfied.

[wonderboy]

I agree, I'm gonna gusset. It's just that I'm curious about the various degree to which people gusset their frames and the size and placement of the gussets. I've seen a half dozen very good threads regarding where to gusset, as well as a guy (with a website selling lots of high end trike stuff) claiming to be the guy who started all this. I've seen lots of pics and have a really good idea of where to put them. But I guess the engineer in me would like to actually analyze the structure and determine what is the best solution from an objective point of view. Like I said, I'll probably strike out on the analysis portion of this (I'm way out of my comfort zone with FEA) but I figured I've got all winter to figure it out.

[jays375]

Another great upgrade is the TRX 450r swing arm.The extra length is great.If your wondering about all the sub farme gussets,do it.Sub frame is pretty weak.

[Dirtcrasher]

Yep, Billy is correct. I order .0625 wall for headlight guards and .0937 for gussets on the frame.

A custom frame would make the 450R swing arm conversion allot simpler!!

As far as stress, past use is a huge factor. There is 1 big heavy motor in there and many are modified for more horsepower and torque.

[brapp]

as far as my experiance i would contact bill from tpc the guy is a wealth of knoledge on the lder stuff too, and has by far the best gusset kit out there, he has been gusetign the 350x frames since the late 80's and has perfected the 350x gusset since then, and is the only person i woudl trust gusseting it

[BOB MARLIN]

My lightly used '85 350x was cracked in 7 different places. MY '86 350x was highly abused and has no cracks at all. There is a difference in the frames between '85 and '86, but not that much. What ever Honda did, it improved it.
By the way, the TPC gusset kits are thin. No more than 1/16, but they seem to do the job just fine.

[Dirtcrasher]

I dropped down to .09375 from .125" wall. Gotta be something beefie in a few places......

At least 3 different things were done to try to strengthen that back engine bolt upper tube/mount. Seemed like after a bunch of runs they changed it and then again. I think it was last year that I posted up that OEM upper tube and the engine mount area.

Last I heard, members PMing me about gussets kits and I sent them to TPC. TPC posted they wouldn't be making them for long time; And I said I don't have the time,desire or a water/laser CNC machine.

Get some steel and trace out your own.

Use a cereal box, trim to a nice pattern, transfer to metal and do anything you want.

Just be careful, some guys get naked 350X frames and go nuts with gussets and then a bolt won't be reachable after it's powder coated. ALWAYS do a complete mock up......

[tony8008]

hey guys, just wanted to drop in and tell you i got my kit last week from tpc. He has started making them again. get em while there hot!

[wonderboy]

Hey everyone, thanks so much for the advice. With regard to the TPC gusset kit, I've got more time than money right now. I've got the steel and a long cold winter coming up to tackle this project. I'd really just prefer to make them myself.

DC: I've reviewed your thread more than just a few times and it will be my main guide. Like I indicated above, I would like to do a little engineering analysis if I'm able to find the right tools (computer programs) that I can figure out. If all else fails, I'll just use the pictures in the threads as my guide. I agree about the cardboard template technique. I'll get the cardboard just right and then switch over to the steel.

I was initially thinking of using 1/8" but that just seemed too thick to me. I purchased 12 gauge stock, which coincidentally is very close to the thickness you mentioned above (~ 0.1").

Thanks again everyone for the input. This process won't be fast for me, but I'll post up some pics as I progress on this (just don't expect them right away) :)