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1925 3.49hp E3 Crank Pin Advice Needed

Posted: Sun Dec 03, 2017 10:15 am
by Andy.Dunn
Hi
Have family owned E3 needing some engine attention (has not been running for 50 years!). Investigations suggest it was originally taken off the road due to damaged crank pin (it is very scored and part of roller collar has broken). Big end looks worn but should be serviceable. Have tried to locate a replacement crank pin but no luck.

So, question is do we get another crank pin machined to original design or would a better option possibly be to make/obtain straight pin (or possibly machine existing) and fit a modern bearing with big end machined to match new bearing?

Hope that makes sense.

Any and all advice gratefully received!

Thanks
Andy

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Sun Dec 03, 2017 1:58 pm
by Rob Harknett
http://www.alpha-bearings.co.uk/home.htm
These people could supply/make a pin or complete assembly. I understand they are busy and may take time.

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Sun Dec 03, 2017 7:36 pm
by Rob Harknett
another suggestion, Godden Engineering,

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Sun Dec 03, 2017 7:51 pm
by Andy.Dunn
Hi Rob
Many thanks for your suggestions. Will give both a call and see what advice they can provide about best way to move forward.
Best wishes
Andy

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Sun Dec 03, 2017 8:52 pm
by g80csp11
Alpha are very slow and expensive , im just having a new pin for my 1927 H4
can you measure yours , if its narrower than the 1927 then I might have a new one in stock . NOS
its to narrow for 1927 hence I did not use it
it says SV , def AJS

send me details , I'm much cheaper than alpha but you will need to fit it your self !

PS my new one is being machined at work , then hardened and ground

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Sun Dec 03, 2017 9:02 pm
by Andy.Dunn
Thanks for the reply. Don't have any measurements to hand and too cold and dark for garage now but will give it a go tomorrow. I understand the 1925 and 1926 are same while 1927 on is different but no idea what difference might be. Fingers crossed...

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Mon Dec 04, 2017 7:47 pm
by Andy.Dunn
Okay. The old man has knocked up the following giving rough details of the crank pin dimensions. How does this compare?

Image

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Mon Dec 04, 2017 7:57 pm
by g80csp11
I will have a look tomorrow at work it's on my desk , I think !

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Tue Dec 05, 2017 8:58 pm
by g80csp11
good news is that I have a new crankpin and outer ring for your bike
send me a pm with your contact details
have to use second hand nuts as I don't have new ones

the outer ring will need machining to get the running clearance correct , this is normal on all big end assemblies
you can even have it before Christmas ( much quicker the Alpha )
last one NOS , that's what Les at Russell motors always tells me


Once I have my new one made for my 1927 H4 ( bigger pin ) , I could always make more to order


Peter

Re: 1925 3.49hp E3 Crank Pin Advice Needed

Posted: Tue Dec 05, 2017 9:25 pm
by Andy.Dunn
Hi Peter
PM sent
Andy