For any of these suggestions you or someone will need access to a graphic program (PhotoShop, PaintShop Pro, Painter, etc). If the logo you are using is a tif file, try it as a jpg. If it is already a jpg, see if the size can be reduced by saving it at a lower resolution. Also try to find out what the "size" of the file is - a file created to print on 8 1/2 X 11, is usually larger file size than if were sized to print on 3 X 5, etc. Also a monochrome (black/white) file is less size than a gray scale version. Color is larger than grayscale.
We have had the logo resized with considerable reduction in file size down from 81Mb to 4Mb, Dwg files are even smaller.
Original solidworks file is 20.6Mb with 4 sheets
an original gif file of 82kb gave the following results for each sheet 80.6Mb, 80.4Mb,79.6Mb,78.9mb in dxf
a resized jpeg file of 51kb gave 3.95Mb,3.77Mb,2.96Mb,2.31Mb dxf
with 1.19Mb, 1.18Mb, .938Mb, .738Mb. dwg.
Thanks for the input, & thank you to Peter & John also.
Probably kicking in an open door but just in case you haven't thought about it....
Rescale the logo to the size it will be on the drawing. If you don't have access to any fancy program such as photoshop then you can always do it with irfanview (http://www.irfanview.net/). With it you can scale it down to the wanted size, bring down it's resolution, crop it and change it to a different format.
Two options to try.
What's the format of your logo (Eg. bmp,png etc..). Bmp format takes big size.
Try to export/save as DWG format instead of DXF (DXF takes big size too)