Author Topic: Circlip warning.  (Read 1737 times)

Offline alanp

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Circlip warning.
« on: 14.09. 2010 16:03 »
I know this is obvious but I thought I was meticulous (don't we all?) and still made the mistake of not double checking that the circlips I had just installed were actually fully in their grooves in the pistons, when I thought that I had done it properly.
Attached is a photo of a circlip which was not fully in it's groove and moved towards the cylinder wall and proceded to lunch on the bore. You can see the polished/worn marks on the circlip face.
Needless to say this was an expensive mistake as well as costing me precious good weather riding time.
Alan
Member of the 'Last of the Summer Wine Club - Jennycliff'.

Offline Goldy

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Re: Circlip warning.
« Reply #1 on: 14.09. 2010 17:11 »
Sorry to hear that, I prefer the wire circlips, they are a real pain to remove and I always think that they are more secure.
56 A10 Golden Flash - Restore, ride, relive.                                          
56 C12 BSA project ongoing

Offline beezalex

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Re: Circlip warning.
« Reply #2 on: 14.09. 2010 18:25 »
Did you fit that in a radius groove?  Rectangular section snap rings like the one shown are not interchangeable with circular section wire clips.  Pistons are machined for one or the other, never both.
Alex

Too many BSA's


Offline taroha10

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Re: Circlip warning.
« Reply #3 on: 14.09. 2010 18:49 »
I was just musing the new topics and had to say how much I love the profile picture from Beezalex.I love to see a bike getting some action like this! Yee Ha!!!
Keep up all the good work all of you.The forum is splendid!
Cheers Taroha10

Offline alanp

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Re: Circlip warning.
« Reply #4 on: 14.09. 2010 19:00 »
Alex, I've just been into the garage to check the grooves in the old pistons and they are correct for the circlip type. It's entirely my fault.
Member of the 'Last of the Summer Wine Club - Jennycliff'.

Offline beezalex

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Re: Circlip warning.
« Reply #5 on: 14.09. 2010 19:33 »
Well that's a bummer, alan.  I had a similar thing happen to my VW truck, but cylinders there are a little easier to exchange.

Torah, thanks for noticing the pic.  It's a bit of a cheat because it's actually my A50 that I'm riding there.  While the Golden flash gets similar treatment on occasion, I have yet to have somebody snap a picture in such a "dymamic" pose.

Cheers.
Alex

Too many BSA's


Offline wilko

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Re: Circlip warning.
« Reply #6 on: 15.09. 2010 00:12 »
Are you double sure about the correct grooves? It's very hard to tell sometimes without a magnifying glass. The wire type are much more common.

Offline alanp

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Re: Circlip warning.
« Reply #7 on: 15.09. 2010 08:47 »
Yep, I used a magnifying glass and a sharp ended probe to make sure that the grooves were flat and sharp edged at their bottoms.
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Online Triton Thrasher

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Re: Circlip warning.
« Reply #8 on: 15.09. 2010 11:11 »
Make really really sure there isn't wear on the big ends.  The hammering effect can make circlips take a walk.  Happened to me.

Offline A10Boy

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Re: Circlip warning.
« Reply #9 on: 16.09. 2010 13:20 »
Were those clips suppied with your pistons, as they are not good enough for use in pistons, if they were you should take it up with your supplier.
Regards

Andy

1958 Super Rocket
Plus
1974 Kawasaki Z1a
Yam XJR 1300

Offline alanp

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Re: Circlip warning.
« Reply #10 on: 16.09. 2010 16:56 »
That's an interesting comment Andy. The pistons were on the bike when I bought it. They were JPs and the gudgeon pin holes in the pistons didn't have the notch to remove wire circlips, so this combined with the deep square grooves, it seems that the circlips with the eyes were correct for these pistons.
I had always assumed that the use of wire type clips was to reduce costs and reduce reciprocating weight. The wire clips have a very shallow rounded groove so the eyes type look more secure. Am I getting this wrong?
If they are less secure maybe I did install them correctly after all and one just let go.
The +.020 Wisecos now fitted have the wire type clip.
Alan
Member of the 'Last of the Summer Wine Club - Jennycliff'.

Offline beezalex

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Re: Circlip warning.
« Reply #11 on: 16.09. 2010 17:07 »
That's an interesting comment Andy. The pistons were on the bike when I bought it. They were JPs and the gudgeon pin holes in the pistons didn't have the notch to remove wire circlips, so this combined with the deep square grooves, it seems that the circlips with the eyes were correct for these pistons.
I had always assumed that the use of wire type clips was to reduce costs and reduce reciprocating weight. The wire clips have a very shallow rounded groove so the eyes type look more secure. Am I getting this wrong?

Actually, Alan, I think the wire-type clips are slightly superior.  Pistons supplied with them usually have a chamfer on the wrist pin that actually pushes the clips into the grooves whenever the wrist pin comes in contact with them.  They therefore need very little spring tension.  That said, when properly applied and installed, both types seem to work well.
Alex

Too many BSA's


Online chaterlea25

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Re: Circlip warning.
« Reply #12 on: 16.09. 2010 23:49 »
Hi Alan and All,
According to "Tuning for Speed" the "Seegar" (sic) type of circlips should be fitted with the sharp edge outwards!!
As BeezaAlex says the pins for wire type are chamfered at the ends, the pins should be flat ended for flat circlips

A10 Boy, Millions of vehicles are driving around with flat type circlips  ???? ???? ???? ???? ????

The important thing is to stick with what the maker intended  *ex* *ex*

Cheers
John o R
1961 Super Rocket
1963 RGS (ongoing)