Are they a worth while investment? (SRM conrods)

[JulianS]

I put map rods in mine. They are rather nice.

 No problem with pop-up piston.

 I will let you know.

Lee

Lee, isn’t yours a Golden Flash with 355 cam and 7.5:1 CR Pistons?

Mine is a 1962 Super Rocket, with 357 cam, 8.25:1 CR Pistons and big Valve head (67-1549).
I’m very concerned about valve clearances and need to be certain before pulling the trigger on these.

Now I know to avoid the SRM billet allot con rods! I thought I trusted SRM and thanks to the knowledge on this forum I won’t be getting them.

Now I need to do more research on the MAP H Beam forged rods.

I dont see why you think there is a problem with the SRM rods?

 They are the correct between centres length as per BSA originals whereas the MAP rods are over length.

I can confirm that the Thunder Engineering rods are the correct BSA specified length between centres - quite noticable when I compared mine Thunder rods with R and R rods (which I wish I had not wasted my money on)

Before I bought Thunder rods I took my crank/R and R rods/pistons etc to SRM to be balanced. They warned me about the  rods being over length but, unfortunately did not have any of their own rods in stock or I would have bought a pair and scrapped the R and R, which would have saved me some subsequent troubles with piston/valve clearance.

[bl**dydrivers]

It says on Thunder Engineering NRE centers are 6” and 6.5”.

http://www.thunderengineering.co.uk/products

[KiwiGF]

It says on Thunder Engineering NRE centers are 6” and 6.5”.

http://www.thunderengineering.co.uk/products

The NRE rods presumably are for Triumph/Nourish tuned engines, if you order rods for an A10 they are the correct length.

http://www.nourishengineering.co.uk/page.php

[jjbsa]

I think the American-made R&R (top quality competition goods) rods deserve mention.  Wassell import them (!) and they are good.  The bolts are made by ARP, 3/8" diameter and torqued to 50 lbs ft.  They are 6.5" between centres (0.8mm too long) but this is easy to deal with.  The joint face between the rod and the cap is serrated and they are machined for advanced gudgeon pin lubrication.  I have fitted them in two A10 motors and an A65.  The two features I really like are the large tough bots and the serrated joint faces.  I enclose some pics.  Cheers,  Jon

[muskrat]

Yep, that's what I put in my Cafe after the blow up. All good.
Cheers

[bl**dydrivers]

Are they not the same that SRM sell? Just they rebranded them.

[JulianS]

SRM rods certainly not a rebranded R and R. They are made with the correct length between bearing centres and more metal at the big end;

http://shop.srmclassicbikes.com/product/srm-large-journal-a10-hi-stength-billet-conrod-each

[KiwiGF]

Are they not the same that SRM sell? Just they rebranded them.

It’s more that SRM are reselling the Thunder Engineering rods (albeit i think they source them from elsewhere nowadays, but they used to buy them from Thunder).

[bl**dydrivers]

I asked SRM about them during the holidays and they finally responded with the following.

ours are correct length of 6.469" centres, the material is stronger then a forged material, it is an alloy, 7075T6 condition ,material extruded under a huge BAR pressure , so gives similar properties to a forging plus the material is a modern and very strong material .
Width of bean is slightly more than original BSA, so the cutouts in cylinders may have to be widened a bit to take the rods.

[KiwiGF]

Barrels will always need modifying I think, just a matter of taking a deep breath and taking an angle grinder to them 

[duTch]

Barrels will always need modifying I think, just a matter of taking a deep breath and taking an angle grinder to them 

  yeah, I had to do that- soft as butter but worked ok. the best bit was it swallowed up some of the broken bit of spigot outside the sleeve