Wanted: Pics of Jeff Smiths 1964 BSA

[TM BILL]

Well if the WDB frames are identical to the C15 frame there should be no problem with allowing the side point B40 motor to race in Pre65 in my opinion. Firko has written some interesting stuff on the inclusion of the Matchy G85 as a follow on model that could be argued as being a precedent for allowing the side point B40 in Pre65 as a follow on, no distinct difference/advantage model engine.

I would of thought that someone on the classic commission would be reading this and might provide us with some answers on why the rule against the side point B40 is in place.....

Huskibul, if your parts manual is like mine is for my B44, it will have all the dimensions of the frame. That being the case, you might be able to compare your frame with the C15 and use the information as indisputable evidence for your claim as a flow on model. It all helps when it comes to dealing with officialdom 

Good luck with that  like the optional B arm its much more fun to enjoy the power trip and mind fork people 

[firko]

As shown below, the C15 and B40 frames are very similar, the only noticeable difference being the height/length of the steering head and apparently the top tube diameter. The B44 frame is very different in every aspect. I have a 1959 C15 frame identical to the one shown that's eventually destined to house my 500 Triumph motor for pre 60. There is quite a lot of structural work needed to get them into race ready condition, especially around the steering head and swing arm areas.  http://www.bsa-c15.org.uk/c15_frame_and_suspension.htm
                                                                             
                                                                               1960 BSA C15 frame
                                                                             
                                                                               1963 BSA B40 frame
                                                                             
                                                                              1966 BSA B44 frame

[huskibul]

   That 66 'B44 frame looks identical to my 1964 C15E (enduro) frame and to the  Army B40 parts catalogue frame - would that classify them also as carry-over ?

[firko]

I just found this 1960 ex works B40/C15 trials bike.......it looks like points to me . I do suspect that it may have had some upgrades in its life however.

                                                                               
                                                                               
The ex-works, Jeff Smith, Jim Sandiford,1960 BSA 343cc C15/B40 Trials Frame no. C15S 2580 Engine no. B40 3294

[FourstrokeForever]

The frame on the Trials bike looks totally different to the C15 and B40 frames Mark. It looks more like a B44 to me.... Nice looking jigger though.

"There is quite a lot of structural work needed to get them into race ready condition, especially around the steering head and swing arm areas".

Are frames allowed to be modified with extra gusseting and the like Mark? I was led to believe that the frame had to be "as per the parent frame".....

[firko]

Are frames allowed to be modified with extra gusseting and the like Mark? I was led to believe that the frame had to be "as per the parent frame".....

Yes frames can be modified. Think of the lowered DT1 frames, any number of lengthened swingarms, and the many other 'cut and shut' jobs that make for turning a horrible, ill handling crapmobile into a half decent racer. The C15 frame has been modified for trials and scrambling since the day they were released. The two main areas are to triangulate an extra top rail from the top of the steering head to somewhere near the rear tank mount and to gusset the very flimsy swing arm pivot area. There is (or was) an excellent 'blow by blow' blog from a guy modifying his frame for trials but I'm buggered if I can find it. The photos are excellent and he even gives gusset measurements and overall dimensions. I had full intentions of saving the site so I can use his ideas on my own C15 but I forgot about it and now I can't find it. Bummer.

The frame on the Trials bike looks totally different to the C15 and B40 frames Mark. It looks more like a B44 to me....

Yeah, I was thinking the same thing, I think the 1960 date might be about 5 years out. Even the look of the bike is mid to late sixties.

[huskibul]

  They must of changed from those earlier c15/b40 high steering stem frames in 64' for c15/b40 and then the first b44 & wdb40 used them as well - afterwards  the  army b40 stayed with them and  b44 went to OIF

[JC]

The C15S & C15T changed from the "swan-neck" style frames pictured in reply # 46 to the later style "competition frame" pictured in reply # 48 in 1963. Note that the frames # is given as C15S *****.

Methinks the 1960 date is a several years out too.

[firko]

This is a slight thread deviation, purely to demonstrate the C15/early B40 frame mods.
Here's an early C15 frame (swan neck as JC so eloquently describes them) fitted with a Triumph T100 500 engine.. This is the basic setup I'm intending to use for pre 60 but I'll be using a B44GP tank and seat for a less cobby , slapped together look. However in the top photo you can just see that the builder has fitted a bolt on top brace from the top of the steering head to just in front of the seat. The frame still features the bolt up rear subframe where I will probably weld it and triangulate a tube from the front subframe mount to the swingarm pivot area in an attempt to tighten up that area. I'll be using an A65 swingarm too which both gives 2" of extra wheelbase and allows for a wider rear hub (I'm using Harley Davidson Sportster). All the dimensions will be as close to the B50 as I can get.

                                                                                     
                                                                                     

[bazza]

 Can the distributor model have electronic ignition?
If so why is it different to points model that's modified to electronic?

[TM BILL]

Can the distributor model have electronic ignition?
If so why is it different to points model that's modified to electronic?

I think its only Aesthetics Mike , changes the appearance of the motor    yes you can run electronic ignition with the distributor .

[Brian Watson]

So MBF.....will you be happy to run a A65 swingarm in pre '60..??

[bazza]

 Amazing- you can run electronic ignition and Fork emulators and modern fork internals (gives an advantage) but cant have points, no performance advantage
I guess given Verns bike now races and Suzuki swingarms now get used one can only hope MA "will get it" o0ne day

[huskibul]

    On the  Bsa c15 owner's site (b40 also) they state boyer bransden electronic ignitions "up to 1964 for distributor" !on the same page  theres  a paragraph  - " Manufacturing at BSA" ,the manufacturing year was august thru to july of the year given   - IE. a bike manufactured in november 1964' would be a 1965 model  ?  ive still seen nothing to say there weren't any production sidepoints before december 1964 ! and  read quite a few articles stating distributors were up to 1964'  - very grey area that should be over -written with whats best for the sport 

[TM BILL]

    On the  Bsa c15 owner's site (b40 also) they state boyer bransden electronic ignitions "up to 1964 for distributor" !on the same page  theres  a paragraph  - " Manufacturing at BSA" ,the manufacturing year was august thru to july of the year given   - IE. a bike manufactured in november 1964' would be a 1965 model  ?  ive still seen nothing to say there weren't any production sidepoints before december 1964 ! and  read quite a few articles stating distributors were up to 1964'  - very grey area that should be over -written with whats best for the sport 

This phrase sums it all up really