Will this weaken my frame too much?

[Macmatic]

I'm building up an '83 GS750ES/EF on an '83 GS750E frame...which is the third frame between my two parts bikes and this frame.

Anyway I'm trying to think of a way to mount the brackets that attach to the front "legs" of the frame to support the EF lower fairing. In the EF frame these bolted up to two threaded inserts on each leg but the E frame I'm using doesn't have these.... So..

I'm thinking about drilling two holes all the way through the frame on each side and running bolts into the bracket, through the frame and putting a nut and washer on each one on the other side. Easy....but safe?

I was thinking about welding on a thin plate to each leg with tapped holes and only having holes in one side of each leg like the OE mounting but I've got the frame painted up and I don't really want to go grinding it down and welding if I don't have to.

Since I want to be able to swap between ES and EF plastic I could also just plug these four holds with plastic caps when I'm is ES mode.

So, whudda ya think?

/\/\ac

[jimcor]

Got nothing to base it on but my own feelings, but I say NO don't drill any holes in the legs.

[Planecrazy]

In my opinion, the trouble you'll go through to grind, weld (carefully without too much heat), and repaint the frame is more worthwhile than gambling with your life. Weakening the frame anywhere is a risky proposition at best.

Better yet, skip the welding and fabricate clamp-on mounting points for the fairing. If you use bicycle inner tube as a sandwiching material you'll have a solid secure non-marring way to mount the fairing, and it'll even be less apt to vibrate.

Good Luck,
Steve 8)

[jimcor]

Steve has the same idea I was toying with. Why not just adapt some bracketry that will mount to your frame with two stainless steel hose clamps per mount?

Back in '73 I had an XS2 Yamaha I bought new. Some frame cracks developed and the bike was off warranty but Yamaha agreed to replace the frame (but no labor, no big deal). Of course the new frame had no numbers.

I moved to California from Cincinnati. To register the bike out west they wanted to drill the leg and pop rivet a number plate to it. Bike never did get California registration. No way was I going to let them drill a downtube. Continued to put Ohio tags on it. Glad I got away with that for 2 years. 8)

[Clone]

Get some U clamps the size of the downtube, weld the nut for attaching the fairing to this, then you can put it on the downtube with some rubber under it to protect your finish. It will also serve the same function as a threaded insert drilled into the downtube. this will be stronger and more secure than hose clamps.

[scotty]

The clamp and rubber mounts sounds safest.

see he doesnt spend all his time in broadcasting. 8O

[gspaul]

Agreed!.....You may add to a frame, but never take anything away.
Holes in the frame! Not a good idea.

[Planecrazy]

The clamp and rubber mounts sounds safest.

see he doesnt spend all his time in broadcasting. 8O

Whenever I'm not running "KLTZ" "Klutz Radio" I like to help my fellow man ... nice to see you back as "you," Scotty!

Steve 8)

[Macmatic]

Get some U clamps the size of the downtube, weld the nut for attaching the fairing to this, then you can put it on the downtube with some rubber under it to protect your finish. It will also serve the same function as a threaded insert drilled into the downtube. this will be stronger and more secure than hose clamps.

U-Clamps! I think thats the ticket right there....

Thanks guys, you saved me a lot of head scratching time and maybe much more!

/\/\ac

[scotty]

The clamp and rubber mounts sounds safest.

see he doesnt spend all his time in broadcasting. 8O

Whenever I'm not running "KLTZ" "Klutz Radio" I like to help my fellow man ... nice to see you back as "you," Scotty!

Steve 8)

Cut the grease job city boy. Where are the avitars of your children???

[Anonymous]

Clamp it for sure! It would suck to ruin the integrity of your frame and break it.[/quote]