Fabricating seat pan for 1980 CB750F Brat style.

Papinbrew

Active Member
Hey all, im in need of some references or links to articles that will help me fabricate a seat pan for my CB750F. Its a stepped design in the frame and I want to keep it that way, I think it looks pretty nice. I heard fiberglass and metal mesh is the way to go, and this will be a first time fabrication for me.

The drawing is pretty much the shape I want to use for the bike seat. A flowing front end that covers the tank tunnel entirely, then stays pretty low along the subframe all the way to the rear tail hoop. Questions I have are setting up mounting points? How to keep a flat section for the foam?
 

Attachments

  • 20170522_164209.jpg
    20170522_164209.jpg
    2.7 MB · Views: 419
  • IMG_20160613_194218.jpg
    IMG_20160613_194218.jpg
    2.4 MB · Views: 410
I always use epoxy mat material to fabricate seat pans.
Take a look at the rear of your frame,your stock frame has a welded "arc" that will keep you from building a flat seat...
This arc is the fixture for your rear fender.

you will NEED this arc for the rear tire not to touch your seat...rethink your seat design, there are MANY seats out there that are plainly dangerous (imagine going over a bump at high speed).
 
I'm in the same boat... contemplating various ideas/plans for a custom seat pan to house the electrical components after I remove the clunky oem battery box.

I was thinking plexiglass (held together by brackets and attached to the frame), which is also lighter than metal, and may look super cool.

I'm also contemplating using good ol' plywood to build the seat pan as well.

What is "epoxy mat material"?
 
Papinbrew said:
Hey all, im in need of some references or links to articles that will help me fabricate a seat pan for my CB750F. Its a stepped design in the frame and I want to keep it that way, I think it looks pretty nice. I heard fiberglass and metal mesh is the way to go, and this will be a first time fabrication for me.

The drawing is pretty much the shape I want to use for the bike seat. A flowing front end that covers the tank tunnel entirely, then stays pretty low along the subframe all the way to the rear tail hoop. Questions I have are setting up mounting points? How to keep a flat section for the foam?
What i like most about your photos is the fact your bike is inside. With the seat pan once you have welded your rear hoop in glad wrap over the frame then cut your fiberglass out to suit you can part wrap the back of the tank also it will give you a perfect pan contoured exactly to the frame.... that is if you're going to use fiberglass..i watched a guy do it on youtube that was after id already made mine i wish i had of seen that clip first.

Sent from my GT-I9305 using DO THE TON mobile app
 
this should lead you in the right direction...there you can see how to use epoxy..

https://www.youtube.com/watch?v=WWUEAMmfgVU
 
Back
Top Bottom