Kick start spring B50

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chobbler
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Kick start spring B50

Post by chobbler » Tue Jul 14, 2020 8:07 pm

My new B50 kick spring is disappointingly weak with the lever arm on.
I was careful to check the number of turns on it when I bought it but it seems only just about good enough to return the lever upright.
Is this normal or should I expect more fierce recoil? Do I try to force another turn to preload it?
The few B series singles have tried before all seem very different from each other.
Is there a "benchmark" B50 kick spring out there I can get?

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Re: Kick start spring B50

Post by twinshocker » Wed Jul 15, 2020 7:46 am

All i can say that mine is weak to.
Thats why the kickstarter is fixed to the frame with a rubber strap in the upright position ( classic 70s fix :mrgreen: )

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Re: Kick start spring B50

Post by Winsur44 » Wed Jul 15, 2020 11:02 pm

I have the same problem. The 2 spring I tried are not up to the job, as the kickstarter is very heavy (actually it weighs a ton). I replaced the return spring new from BSA Unit Singles after a disaster where I kickstarted the bike with the expectations that the kickstarter would always ratchet back to the top position. The kickstarter did not ratchet back up, and in just a short block mayhem erupted.

BEWARE, if you have not checked the The kickstart ratchet nut and lockwasher you can end up like I did. When the kickstarter is all the way down and you drive off, the nut can spin loose from the mainshaft, and cause all kinds of havoc. I was able to repair mine, but the aluminum cover was damaged, though repairable. I had to tow the bike home as the clutch rod was locked up. When I purchased a lot of BSA single parts, it included a bunch of damaged mainshafts. I wonder is they were ruined by the nut coming loose whilst the kickstarter was in the down position while driving. My mainshaft was ok and reusable. My last post on the subject asked about the different springs that I have seen. My question on which one to use went unanswered.
See my post:
viewtopic.php?t=1614

I have used the bungie chord trick to secure the kickstarter in the upright position, though seemingly when it is back up, it will not fall down.
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Re: Kick start spring B50

Post by Barry Creary » Wed Jul 15, 2020 11:22 pm

I’d be checking with PES Mark and Anita have quality parts and have improved the poor quality BSA Enginering (and cheep replacement supplies) well worth a little extra cash. ccmicon

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Re: Kick start spring B50

Post by Momus » Thu Jul 16, 2020 6:49 am

Another part designed by the cleaner when the eng. was at the rubbidy dub.

A springmaker with a CNC coiler will duplicate the std spring in heavier wire no problems.

I use Bells in Thomastown or National Springworks in Campbellfield.
If you love it, lube it.

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Re: Kick start spring B50

Post by 2manyrides » Thu Jul 16, 2020 10:55 pm

I am sad to hear that limp return springs are out there. I have not had to buy one in a long time. But I can tell you I have purchased ones that I would never put on! Or placed an order and received what looks like a b44 spring. So when I find the good stuff, I get spares too. Never had a kick started hang down like described, but for when a spring broke.
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Which one to ride today?

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Re: Kick start spring B50

Post by Winsur44 » Fri Jul 17, 2020 4:59 am

I just got a B44 started after 10-15 years of sitting. I looks to be the same kickstarter as the B50. it goes back up every time. Maybe the my B50 is hanging, It seems to be free, and just a gentle nudge helps it to return.
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