Hello A7/A10 forum
we are concerned that owners maybe having problems with the ARP product supplied by SRM
specifically the ARP bolts supplied as OE replacement for standard rods.
The ARP bolts SRM supply are shipped with the bolt-specific instructions that come directly from ARP. I have been in contact with ARP who have confirmed that the bolt 14AG2.600-1, should be used in accordance with the supplied instructions.
As reflected in this forum, this is not always an effective solution for you guys so I have spoken to Geoff Dewhurst, SRM workshop manager, and he has measured a set of standard conrods, at various torque settings, to find out what was happening. The rods distort by about 0.001? at 37ft/lbs at a perpendicular to the joint face.
The original rods would have been torqued to 22ft/lbs and the big-end face honed to finish, in an ideal world the conrods would be assembled and torqued to the new ARP specification and the big-ends re-honed to suit the new bolts.
As owners probably prefer a straight fit Geoff pragmatically advises the following;
?We have found that in some cases these bolts (ARP) torqued to 37ft/lbs, may distort the con rod end-cap, resulting in a restriction of free rotation, accordingly, SRM recommend reducing the setting to 28ft/lbs with an application of thread-lock on the final tighten, remember the bolts must be tightened and relieved twice with tightening to final setting on the third attempt?
Geoff also adds;
?These bolts were originally for a Triumph application but are advised by ARP to work well on BSA rods. Check for clearance on the scavenge pipe casting (timing side crankcase) on the A10?.
We would like to assure owners that all correspondence with SRM is answered, our internet address changed approx 18mths ago to
www.srmclasssicbikes.com and we apolgise if any emails were lost in this process.
If you would like specialist advice the SRM department heads are;
Jon Jolley, Electrical and wheel building jon@srmclasssicbikes.com
Geoff Dewhurst, Engineering and workshop geoff@srmclasssicbikes.com
Gary Hearl, Stores and parts/model specific info gary@srmclasssicbikes.com
SRM now have a dedicated department for new product design and development and we are working steadily to eradicate specific issues with any products we supply.
Regards
Patrick