AMC conrods, yes or no?

Information relating to the Matchless G12 or AJS Model 31 650cc twin
rayswadling
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AMC conrods, yes or no?

Post by rayswadling »

For info, I did post a picture in "parts pictures, post-war twins". It's just side-on, but you have to appreciate the actual rod part is "H" shaped and so is pretty much hollow

Rods are now in my engine so can't take any more pics...
Don Madden
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AMC conrods, yes or no?

Post by Don Madden »

I went over to see Ed Crowell Saturday & discussed the Carrillo rods. He told me that the firm was bought out recently & is concentrating on newer motors. His last order for AMC rods was refused. The big Mathless twin engine works out to almost 900cc & uses T140 rods & will use special pistons. He has welded on big stubs on each head for oversize charbs but I don't know how big. Also don't know what other head work will be done.

Ed doesn't do computers, but his phone number is: (310)371-2583 in Torrance, California, USA. He is very helpful to me but we have been friends & AMC enthusiasts for a long time. His engineering shop is his major income so don't know how much time he will spend on the phone. Cheers, Don.
mdt-son
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AMC conrods, yes or no?

Post by mdt-son »

Ray,
Thanks a lot for the information provided, which helped me a lot. Order is out.

Don,
I don't know what Ed ordered from Carillo but Barry Deane at Carillo accepted the order for G12 rods straight away. Actually I got dealer terms which I am happy with ( I run a small engineering company).
I will give Ed a ring at a suitable time. Thanks for the info - his project sounds intriguing!

Knut S.
rayswadling
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AMC conrods, yes or no?

Post by rayswadling »

Knut,
Glad to be of help, I'm very happy with the rods I bought, which will go nicely with one of the new crankshafts later this year...
nNext time I want a pair of rods I'll ask you to order them for me


CAB
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AMC conrods, yes or no?

Post by CAB »

Hello Ray
I'm interested in a pair of Carillo rods to go with my new crank. Do you know if the rods that you ordered under the part number quoted above, are actually different from the G45 rods? Presumably you can use standard shells etc with the Carillo rods and no modifications are necessary such as machining chamfers on the rods to suit the 650 cases?
Regards
CAB
zwarts
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AMC conrods, yes or no?

Post by zwarts »

If there's enough interest in getting Carillo to make some twin rods, it may be economically worthwhile for interested parties to get together and put in a bulk order. Unit costs for manufacture, postage etc should be lower than if several people order individually. It certainly seems a folly to invest in one of the new cranks and then fit 50 year old rods (of unknown history). Forged pistons are also worth considering. You can count me in as an 'interested party'!
Bob.Edited by - zwarts on 10 Jun 2012 1:50:27 PM
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bigwol
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AMC conrods, yes or no?

Post by bigwol »

quote:
If there's enough interest in getting Carillo to make some twin rods, it may be economically worthwhile for interested parties to get together and put in a bulk order. Unit costs for manufacture, postage etc should be lower than if several people order individually. It certainly seems a folly to invest in one of the new cranks and then fit 50 year old rods (of unknown history). Forged pistons are also worth considering. You can count me in as an 'interested party'!
Bob.Edited by - zwarts on 10 Jun 2012 1:50:27 PM


makes sense to me too. count me in?
It's all just riding motorbikes
CAB
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AMC conrods, yes or no?

Post by CAB »

Hello

I was thinking along the same lines; no point fixing the weakest link only to find the next one not far behind....

Well that's three of us so far. Shall I start a separate post to gauge interest? I don't think it will be cheap, import duty and then VAT on top of everything including postage. It would probably be cheaper to go for the UK manufactured aluminium ones (link to Thunder Engineering on the on the previous page) if we had a bulk order.

I did buy a pair of JE (not JP) forged pistons for a BSA Spitfire a while back from the US and they looked to good to go in the engine. The only problem is that you had to order non stock items in batches of 4 as I inquired with a friend with a 650 SS. You would therfore need to find two people who wanted +0.020 etc.

CAB
zwarts
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AMC conrods, yes or no?

Post by zwarts »

Whilst in the North of Holland for a race meeting last weekend, I visited the ABSAF establishment. They are making all sorts of goodies for the AMC twin engines and have beautiful new alloy con rods (with ARP bolts)available at 220 Euros each. I would have thought Carrillos would be a similar price.
Bob.
mdt-son
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Re: AMC conrods, yes or no?

Post by mdt-son »

I just posted this nessage in another thread, this tread being more suitable I am repeating the message here.

Hi Ray, I have just read a comment by Steve Campbell from Thunder Engineering, where he claims a twin engine with steel conrods (e.g., Carillo rods) will run harsher than an engine with alloy rods. I find it hard to believe from a solid mechanics point of view, maybe some vibration issues caused by pressure pulses during combustion are at play .... Did you notice an altered engine response after fitting Carillo rods? I'd be very interested hearing about your experience (and others who have fitted steel rods).

Greetings and best wishes for Xmas

Knut Sonsteby
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