Author Topic: Rocker springs v thrust washers  (Read 995 times)

Offline cableguide

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Rocker springs v thrust washers
« on: 17.05. 2016 09:00 »
Greetings fellow A folk.
In the process of re-building my 61 A7SS engine and was wondering if there is any noise benefit in replacing the rocker shaft springs with a set of bronze or steel thrust washers instead.
All ideas most appreciated
Cabe

Online Greybeard

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Re: Rocker springs v thrust washers
« Reply #1 on: 17.05. 2016 09:23 »
Ask Musky. Sounds like fitting the rocker box becomes more difficult as the rockers don't stay put.

Offline BSA_54A10

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Re: Rocker springs v thrust washers
« Reply #2 on: 17.05. 2016 09:56 »
Yes.
A lot quieter with thrust washers
Down side is PIA to set up and you have to cut down hard washers to fit with around .002" running clearence.
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Trevor

Offline muskrat

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Re: Rocker springs v thrust washers
« Reply #3 on: 17.05. 2016 11:06 »
My main intention was to cut down on a little friction/stiction caused by the springs. Less clatter was a welcome byproduct. When fitting the rockerbox I slip rubber bands over the rockers and up and over the opposite side inspection cover stud to keep'em up. Once all fitted cut the bands.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
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Online Triton Thrasher

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Re: Rocker springs v thrust washers
« Reply #4 on: 17.05. 2016 18:05 »
I'm all for people having fun in the shed.

That's the main benefit of such a modification.

Offline Dean

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Re: Rocker springs v thrust washers
« Reply #5 on: 17.05. 2016 20:55 »
I'm tempted to try thrust washers if they'll quieten the top end.
Where would i find suitable washers?
Never tell people your troubles. Half of them are not interested and the other half are glad you're getting what's coming to you.

Offline muskrat

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Re: Rocker springs v thrust washers
« Reply #6 on: 17.05. 2016 21:30 »
I used a collection of the original flat washers that sit between the spring and alloy.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline Dean

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Re: Rocker springs v thrust washers
« Reply #7 on: 17.05. 2016 21:49 »
I used a collection of the original flat washers that sit between the spring and alloy.
Cheers

Thanks Muskrat
Never tell people your troubles. Half of them are not interested and the other half are glad you're getting what's coming to you.

Offline BSA_54A10

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Re: Rocker springs v thrust washers
« Reply #8 on: 18.05. 2016 09:47 »
I had a box full of old bucket rocker shims when I did mine,
The OD was a bit big and a masionary drill with a reprofiled tip did the job of making the hole from a pilot cut with a diamone Dremel tip.
Bike Beesa
Trevor

Offline cableguide

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Re: Rocker springs v thrust washers
« Reply #9 on: 18.05. 2016 10:59 »
Great info guys, reckon I may give it a go as Ive just found that TMS can supply the two sizes of thrust washer but like everything with these bikes best to think and tread carefully before messing something up.

Offline jachenbach

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Re: Rocker springs v thrust washers
« Reply #10 on: 18.05. 2016 13:06 »
When fitting the rockerbox I slip rubber bands over the rockers and up and over the opposite side inspection cover stud to keep'em up. Once all fitted cut the bands.
Cheers
Having several times seen the reference to rubber bands to hold the washers, I've wondered how that worked. Now that you've explained it seems obvious.

Offline Dean

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Re: Rocker springs v thrust washers
« Reply #11 on: 18.05. 2016 21:06 »
Great info guys, reckon I may give it a go as Ive just found that TMS can supply the two sizes of thrust washer but like everything with these bikes best to think and tread carefully before messing something up.

Good to know TMS stock them. I might make the 5 mile trip to get some then *smile*
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Online morris

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Re: Rocker springs v thrust washers
« Reply #12 on: 18.05. 2016 21:35 »
I'm tempted to try thrust washers if they'll quieten the top end.
Where would i find suitable washers?

https://www.onlinemetals.com/merchant.cfm?id=1217&step=2&top_cat=1175

You'll need
1 pack of 0.062 thick x 0.5"ID x 0.75"OD
1 pack of 0.032 thick x 0.5"ID x 0.75"OD
1 pack of 0.0015 thick x 0.5"ID x 0.75"OD
'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
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