Hairpin Valve Springs

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chappers1962
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Hairpin Valve Springs

Post by chappers1962 »

Hi All

Have got wear on the hairpin valve springs removed from the exhaust side (see pictures below).

Question is, what's the acceptable level wear ? I'm really having trouble sourcing replacements. No spares anywhere (including AMC and Andrew Engineering). Nothing on eBay also.

Many thanks
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Mick D
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Re: Hairpin Valve Springs

Post by Mick D »

Hi

I've never seen any defined wear limits for the valve springs but in my opinion your springs are in very poor condition, I wouldn't fit them for fear of fracture.
Why not try asking in the 'Wanted' section of the forum, someone might have a used set in better condition.

Regards Mick
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ajscomboman
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Re: Hairpin Valve Springs

Post by ajscomboman »

I'd hold on a little as the parts service may have some new stock coming in quite soon. ;)
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chappers1962
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Re: Hairpin Valve Springs

Post by chappers1962 »

ajscomboman wrote:I'd hold on a little as the parts service may have some new stock coming in quite soon. ;)
Im hoping so. Spoke to Andrew Engineering and they said they were sending a consignment of springs to the club, however phoned club spares up and they said there wasn't any on order and it could be months before a new manufacturer was sourced! Will phone AE up again today to clarify.
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Rob Harknett
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Re: Hairpin Valve Springs

Post by Rob Harknett »

There are several type's of hairpin springs. So you do need to state what year and model bike the springs are for.
SPRIDDLER
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Re: Hairpin Valve Springs

Post by SPRIDDLER »

I wouldn't want to refit that spring. A weak spring will only limit performance but would probably cause damage if it breaks.............obviously.

Not especially helpful to you in this case but there is a brief ref to hairsprings in the spec's at the end of this article by Ken Bryant (ex Plumstead employee, AMC dealer and one time contributor to these Forums as 'ITMA'). He suggests that the gap in the jaws of a new spring will be 2" and should be replaced when the gap is reduced to 1 11/16". I've never had reason to measure one on the basis that if it feels strong enough (i.e. not too easily inserted) when refitting it then it's O.K.

http://archives.jampot.dk/technical/Spe ... hanics.pdf

(You can't read the 1 11/16" figure in the article in the above link but I have an 'original' clear photocopy which Ken sent to me).
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spookefoote1956
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Re: Hairpin Valve Springs

Post by spookefoote1956 »

Hail Joe Lucas ............ Prince of Darkness!
All my bikes are original........ to me!
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ajscomboman
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Re: Hairpin Valve Springs

Post by ajscomboman »

chappers1962 wrote:
ajscomboman wrote:I'd hold on a little as the parts service may have some new stock coming in quite soon. ;)
Im hoping so. Spoke to Andrew Engineering and they said they were sending a consignment of springs to the club, however phoned club spares up and they said there wasn't any on order and it could be months before a new manufacturer was sourced! Will phone AE up again today to clarify.
Well take it from me, they are definitely on their way as Joan has confirmed they're paid for and ready to go. I'll sort out the other issue at Kettering later! :headbang:
G15 Roy
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Re: Hairpin Valve Springs

Post by G15 Roy »

I have spoke to Kettering and Andy was unaware that the delivery had been brought forward, rest assured they are on route and will be with us next week sometime. Keep checking the web site for updated stock.
Roy
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chappers1962
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Re: Hairpin Valve Springs

Post by chappers1962 »

G15 Roy wrote:I have spoke to Kettering and Andy was unaware that the delivery had been brought forward, rest assured they are on route and will be with us next week sometime. Keep checking the web site for updated stock.
Fantastic - many thanks :D
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