SR 90/100 Model Question

[superspin1]

I've noticed in looking at the various pictures of the SR 90 and 100 models, a difference in the way the rear fenders are cut? Some have almost vertical cuts and others have an almost horizontal cut where the fenders are shortened? Did Bridgestone vary the cuts on different years/models?
I'm interested because I want to build an SR clone. With my chances of finding a true SR 90/100 being next to impossible, I think it would be a fun project to turn my pre-injected Mountain 90 into an SR clone. I have a BS60 tank already and was going to make the rear fender cut next, hence my looking at all the pictures. I saw Gene's original SR 90 and I'm thinking I'll try and copy that cut style (almost a horizontal type cut). But I'm curious as to why the different styles?
 

[CL-100]

Here's a few things I've heard anecdotally about the SR's.  The fenders were bobbed by race operators to help with weight and to facilitate getting the rear tire on/off quickly.  I believe the longer fender with the horizontal cut is how they came from the factory.  If you search this site, somewhere is a photo of a one-page ad showing how the 100/175's looked new.  I've never seen any photo ads for the SR90.  Additionally, race operators also removed front fenders and the components of the front brake.  Again, I presume this was for weight savings and the fact that dirt track bikes didn't use the front brake.

Hope this helps.  Please consider posting pics of your project as you make progress.  Good Luck.

[moonpup]

Here's an ad I purloined from another site that has a great side view of the BS SR100.....

[Hal French]

Pictures from my SR-100

[superspin1]

Thanks guys for the background info and the original ad, that really does help me understand why the differences. A special thanks to Hal for his pictures with the tape measure. Now, I can actually locate where to make my cut.

[slawsonb]

Hal, I am still in awe of your racer. Very nice!
...bert

[superspin1]

I agree, Hal's SR looks gorgeous! Hal, please post some more pictures of your SR 100, we would all love to see it. I hope you guys will allow me to ask another question, regarding the seat, does anyone know if Bridgestone took an existing seat and modified it for the SR racer? If so, anyone out there know what seat pan they used, or was the seat made from scratch for the SR?
Hal, if I might be so bold as to ask, would you mine posting some pics of your SR 100 seat pan with the tape measure showing length and width? That would really help me out in trying to come up with something similar. Again, finding one out here in the Northwest would be highly unlikely so I'll have to improvise I'm thinking. If I had a picture and some dimensions, I can probably come up with something close. Thanks again everybody for helping me on this journey.

[Mopar5426]

   Hey Dave

I Have Both A 100 & 90 SRIll Make Sure There Cut The Same When I Get Home


GENE