Model 30 Con Rods

Information relating to the Matchless G11 or AJS Model 30 600cc twin
Victor Johnstone
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Location: Argyll And Bute UK

Model 30 Con Rods

Post by Victor Johnstone »

Following helpful advice from here (thanks again all) I stripped my engine down to find that I am now the proud owner of a very nice AJS Model 30 but with a cream-crackered drive-side con rod. Anyone have any idea where a replacement can be found? The AMOC spares scheme doesn't seem to have them. Cheers.
Mick D
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Re: Model 30 Con Rods

Post by Mick D »

Hi

Try AMC Classic

Regards Mick
Victor Johnstone
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Location: Argyll And Bute UK

Re: Model 30 Con Rods

Post by Victor Johnstone »

Cheers mick. Sent them an email.
JEAN-NOEL
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Re: Model 30 Con Rods

Post by JEAN-NOEL »

Hello William,
finally you are almost lucky: you can use interchangeably the connecting rods of 500, 600, and 650!
Preferably choose a workshop balancing the connecting rods and the crankshaft.
Kind regards.
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dave16mct
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Re: Model 30 Con Rods

Post by dave16mct »

I'd phone rather than email. They take a very long time to answer emails as they get so many.
Dave.
Victor Johnstone
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Re: Model 30 Con Rods

Post by Victor Johnstone »

Thanks all.yet again!

Thunder engineering got back to me. They look good if a trifle pricey. Maybe worth it however. Does anyone have experience of their products
Groily
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Re: Model 30 Con Rods

Post by Groily »

Top product. Have them in my Mod 31 on a club new crank, and have another pair and another new crank in the wings.
Maybe a bit OTT if you only need one, but on the other hand, depending how many ££ you actually have to invest in the rebuild, the cost may seem reasonable.
If you do find second-hand, I'd have it crack-tested and checked for ovality at the big end (and trued up if necessary). I wouldn't just fit it.
Victor Johnstone
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Location: Argyll And Bute UK

Re: Model 30 Con Rods

Post by Victor Johnstone »

Thanks again. Mulling it over!
Victor Johnstone
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Re: Model 30 Con Rods

Post by Victor Johnstone »

Latest, 2nd hand rod from AMC. Oval, although to be fair they were up front and said sold as is and I could check first. A bit tricky with me being 100s of miles away.. Anyhoo. Local precision engineer (a classic bike enthusiast himself - pre WW1 Harleys and Indians) checked the crank. Oval journals. One side worse than the other. I decided rather than machine the 50 quid 2nd hand rod, I will go for new Thunder Engineering. Question. Where can I get the serviceable dimensions of the journals and can I get undersized shells? Sorry if daft questions.
Groily
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Re: Model 30 Con Rods

Post by Groily »

http://archives.jampot.dk/book/Workshop ... CHABLE.pdf
See page 24.
And Yes, most sizes, most of the time. From Club. Or AMC Classic Spares, etc.

PS Radii, radii, radii. Critical they be retained. If in doubt, go to people such as T&L Engineering, see ads in Jampot mag, who do these all the time and will tell you if the crank can safely be reground or is a doorstop. Many of us have some of each. Loss of radius = Breakage Very Likely, so has to be done right.
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