B50 Rocker box substitute

Here you can talk about all kind of TECH for the B50 B44 B25 And Other BSA unit Singles

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neil
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B50 Rocker box substitute

Post by neil »

Hello all,
Apologies as I know that this subject has been brought up before but don’t think the answers were conclusive.
I have drilled out the stud holes on a C15 rocker cover including the dowel hole at 3/8” to suit a B50 head without reducing the wall thickness to paper thin.
It fits nicely all round and as far as I’m aware, the rocker arms were all similar throughout from C15- B50.
I am wondering though, if the rocket shafts on the C15 are in exactly the same location as the B50?

Also, can ask how CCM fitted a decompressor if they did not use the standard B50 valve lifter arrangement?
Cheers
Momus
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Re: B50 Rocker box substitute

Post by Momus »

No idea what CCM did but the go these days for a manual decomp valve is a Stihl or Husqvarna chainsaw unit.
If you love it, lube it.
neil
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Re: B50 Rocker box substitute

Post by neil »

Where would you fit a chainsaw decompression valve on the B50 head?
Momus
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Post by Momus »

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Last edited by Momus on Sat May 30, 2020 6:59 pm, edited 2 times in total.
If you love it, lube it.
neil
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Re: B50 Rocker box substitute

Post by neil »

Good idea.

BTW ,I’ve found that although it was easy to open up the stud holes and the cover fitted nicely, that was before I fitted the valves. The cover will now not fit as it clashes with the valve springs.
So, will not be suitable. ☹️
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SteveS
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Re: B50 Rocker box substitute

Post by SteveS »

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Hi Neil

I can understand your need for the experiment, as genuine B50 rocker box castings are thin on the ground. Thanks for letting us know, it will help others in the future.
I am wondering though, if the rocket shafts on the C15 are in exactly the same location as the B50?
Yes they are :thumb

I guess you have seen this other thread? Rocker Box contents - interchangeability?
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Steve Sewell
neil
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Re: B50 Rocker box substitute

Post by neil »

Excellent Steve.
Cheers
Neil
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