Author Topic: Primary chain size confirmation  (Read 691 times)

Offline coater87

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Primary chain size confirmation
« on: 07.02. 2016 08:26 »
 Quick question.

 I believe the stock primary chain on a SA bike is a 428 chain.

 That is going by the bits of chain and sprocket that came in the pillow cases full of parts. I know their was som Japanese parts mixed in, and just want to be positive 428 is correct for the BSA.

 Lee
Central Wisconsin in the U.S.

Online Billybream

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Re: Primary chain size confirmation
« Reply #1 on: 07.02. 2016 09:17 »
Primary chain size is 1/2 x 0.335 x 0.305, 69 pitches. Type 428 is correct.
1960 Super Rocket, owned since 1966, back on the road 2012 after being laid up for 29yrs.

Online chaterlea25

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Re: Primary chain size confirmation
« Reply #2 on: 07.02. 2016 12:38 »
Hi Lee,
Usually the chain has to be an original style with narrow sideplates, the "H" chains will foul the rear primarycase
Make sure it is a quality made chain not industrial type,
I have been fitting "Regina" brand chains for some years now
Some A10's were lower geared and used a 69 link chain that needs a half link  *sad2*
70 links is correct with 21(?) 22 & 23 tooth engine sprockets

HTH
John
1961 Super Rocket
1963 RGS (ongoing)

Offline coater87

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Re: Primary chain size confirmation
« Reply #3 on: 08.02. 2016 03:56 »
 Thanks guys,

 I suddenly had a moment of uncertainty, and did not want to buy a bunch of stuff and then find it is not right.

 Lee
Central Wisconsin in the U.S.