350x Frame Crack and Gusseting Questions

[Fixer_Upper]

Hello, my 350x has unfortunately fallen to the fabled frame crack right above the left foot peg. Unfortunately for me, the tube didn’t just crack in one place, but yet another an inch or so above the first crack. Looking at how it broke (as well as the stress cracks starting around it), I think I need to cut out the old tubing and weld in some new. If you guys have any better ideas for fixing the break itself please let me know, I’m open to all ideas at this point. However, welding in a new piece of tubing will not fix the original problem at hand. I’m a 6’4 250 lb rider and although I’m not jumping the 350x, the frame is definitely under some serious pressure just because of my sheer size. If you know of any good gusset kits for these it would be greatly appreciated if you could let me know about them. If they were available, I would also like (almost prefer) a set of Auto-Cad drawings so I could cut them out on a water jet table. I’m not sure if they are out there, but it’s worth a try. I’m also thinking about designing some gussets myself and cutting them out, but I suppose I need to know what the real weak points are. Sorry for so much information, any help is greatly appreciated! Have a great night guys!

[BOB MARLIN]

The gusset for that area that came in the TPC kits was a piece that wrapped around the problem area to cover all the cracks then a gusset was then added to that. So you would weld up all the cracks then smooth then out, then add the wrap around re-enforcement and weld that in, then the gusset is added to that. The 350x frames crack in some unexpected areas also. When I fixed the foot peg-pivot bolt crack
on mine (the same area you are dealing with) I went ahead and tore everything down to PC the the frame and was amazed out how many other cracks I found. The strangest ones were under the seat on the cross member that the seat pins locate into. It had cracks in 3 places. There is about half a dozen places are the 350x frames that are prone to crack. A few less on the '86 frames. Go to the "TPC Trikes"
website . They show a gusseted 350x frame where you can see a lot of the places you should gusset. If their kit is still available - it's well worth the money. But beware. Although I've had nothing but good experience with TPC , others have had difficulties.

[Dirtcrasher]

I can try to find some pictures for you, I've done a couple dozen of these frames.

I've had them just cracked or completely severed and bought some DOM tubing to work with. I wrap that whole tube around to the back and tie that in to my gusset. I drill 10mm holes in the wrap, staggered throughout so that I can weld the wrap to the original Honda metal as well. I gusset the lower subrframe triangle and the upper subframe triangle and I leave them long enough that I can weld them to my full frame wrap. Once I wrap it and weld them all together they are super strong and I haven't had one crack again. I usually use 3/32 or .09375 steel for the gussets and thickness of the DOM tubing.

The best frame they made was in early to mid 1986 when Honda actually did a half wrap around the backside. I have 1 frame that I run and I haven't broke that one yet so it certainly helped. They made at least 3 versions of the 350X frame.

[Dirtcrasher]

I think I did this one about 10 or 15 years ago, my buddy still hasn't had a chance to get it together. See how it's welded into the upper gusset? I try to catch both gussets when I do them now. I've fixed them in a few other ways and they usually hold up, I'll add a sketch of another way I've done it.

https://uploads.tapatalk-cdn.com/20220418/50c5d1db403a33a5ec765f1a1e3d61a2.jpg

[Dirtcrasher]

I took the time to draw a sketch and "Tapatalk" will not upload the image. Keeps saying it failed because it's a "MIME" format. It's the same phone, taking 2 different pictures within 10 minutes... For whatever reason, it refuses to upload.

To this day we STILL cannot easily upload images in this forum. Tapatalk was my work around but it's now failed due to it being a sketch with words on it I guess??...

[Dirtcrasher]

I'm 45 minutes into this. It's why I rarely come here as i cant spendvan hour on a 5 minute job. Hope it gives you some ideas!!https://uploads.tapatalk-cdn.com/20220418/6bae7468b43151cb2ff0cb47bbd0d96d.jpg

Sent from my SM-A426U using Tapatalk

[Jim mac]

on posting pics off my phone, I just text myself the pic from my gallery and save the photo. then when I want to post a pic, I just pic the saved pic from my text and itnloafs every time. jim

[Fixer_Upper]

Thank you so much!!! This is very helpful and greatly appreciated. Have a great day!