New Zealand Conrods

Status
Not open for further replies.
Not saying these are the same but I bought some very very similar rods for a Triumph and the bolts were
3/8" shoulder bolts. which means the shank is 3/8" diameter but the thread was 5/16" x 18 tpi which
meant the root diameter was about 1/4" diameter . I wasnt impressed at all and got rid of them
The above rods advert doesnt seem to specify what bolts they use.
 
It says they have ARP 2000 rod bolts with a strength of 200,000 to 220,000 psi.
ARP products are made in the USA so have no Chinesium content.
 
Last edited:
ahh. I missed that bit. I use ARP8740 bolts 180,000 to 210,000 psi. in my steel rods
 
Looks like some case relieving will be needed before the crank will turn, just like most other billet rods.
 
Time Warp said:
It says they have ARP 2000 rod bolts with a strength of 200,000 to 220,000 psi.
ARP products are made in the USA so have no Chinesium content.
Click to expand...
Psi is an indication of the strength of the material, not the strength of the component. Strength of say a connecting rod bolt would be (indicated strength of the material) x (cross section area of the bolt) and expressed as a force.
 
correct Dances and most would know this. however through the eyes of the purchaser , the higher the
PSI regardless of how it is portrayed is the superior material. I'm certain many factory conrod bolts
would not come anywhere near the strength of ARP 8740 bolts
 
johntickle said:
Looks like some case relieving will be needed before the crank will turn, just like most other billet rods.
Click to expand...
Several aftermarket rods have bolts that will not clear the Norton cases and require cutting away material.

The "Carr" type bolts offered by Carrillo are good for life (as long as you do not overtighten them). And they clear the cases no problem. Not all Carrillo rods come with these high quality bolts. They are more expensive but worth it in my opinion.
 
A little surprised they used 7075, the tensile drops with temperature most probably making it no stronger than a forged RR alloy rod. I really don't get billet con rods on a Norton, Steel - yes, Ti yes. if they have that much confidence in billet, then make one the same shape and dimension of a forged rod, something tells me it would never sell.
 
jseng1 said:
Several aftermarket rods have bolts that will not clear the Norton cases and require cutting away material.

The "Carr" type bolts offered by Carrillo are good for life (as long as you do not overtighten them). And they clear the cases no problem. Not all Carrillo rods come with these high quality bolts. They are more expensive but worth it in my opinion.
Click to expand...

Hello,
I often wondered, why the bolt- heads are mounted from below, which means that you have to split the crankcase for removing the conrods.
If you'd mount the bolts from above (from the cylinder- flange) you could remove the conrods without splitting the cases. Just have a look at the BMW- rods. Here we have the bolt- heads from the cylinder side. That way you have easy access for removing them. So, if you ever get new conrods made remember get the thread cut in the rod itself.
Oh yes, and you'd have no problems with the rods hitting the crankcase during the rotation of the crank.
Not a bad idea, isn't it?
Best Regards
Klaus Monning
 
Last edited:
Klaus Monning said:
Hello,
I often wondered, why the bolt- heads are mounted from below, which means that you have to split the crankcase for removing the conrods.
If you'd mount the bolts from above (from the cylinder- flange) you could remove the conrods without splitting the cases. Just have a look at the BMW- rods. Here we have the bolt- heads from the cylinder side. That way you have easy access for removing them. So, if you ever get new conrods made remember get the thread cut in the rod itself.
Oh yes, and you'd have no problems with the rods hitting the crankcase during the rotation of the crank.
Not a bad idea isn't it.
Best Regards
Klaus Monning
Click to expand...
Agreed, a very good idea :)
 
cliffa said:
Agreed, a very good idea :)
Click to expand...

Hello,
I had this idea since I took my first Atlas apart, which is more then 20 years ago.
I really only wanted to check the big end journal surface and fu...ed the world, because I had to split the crankcase for the job.
By the way the camshaft is the same idiotical design. With a bigger flange from the timinge side you could pull out the camshaft without splitting the case. Hadn't Axtell this idea first? He even offered a kit, didn't he?
Some years later I had problems fitting short- stroke conrods. Again I had to take away material from the inside of the cases.
That was the time when I remembered my BMW (certainly also "Special") with their solution of conrods.
I think Volkswagen as well as Porsche have the same solution (bolt heads from above).
Ok Fellow- Nortonists if I find the right cash for a new set' of this type of conrods I'd be the first customer (steel or alluminum, what ever) for conrods with bolt heads mounted in from the cylinder flange)
Best Regards
Klaus
 
  • Like
Reactions: baz
Klaus Monning said:
Hello,
I often wondered, why the bolt- heads are mounted from below, which means that you have to split the crankcase for removing the conrods.
If you'd mount the bolts from above (from the cylinder- flange) you could remove the conrods without splitting the cases. Just have a look at the BMW- rods. Here we have the bolt- heads from the cylinder side. That way you have easy access for removing them. So, if you ever get new conrods made remember get the thread cut in the rod itself.
Oh yes, and you'd have no problems with the rods hitting the crankcase during the rotation of the crank.
Not a bad idea, isn't it?
Best Regards
Klaus Monning
Click to expand...

Its been done. I saw a set that was custom made for a Norton with the threads cut into the rod caps instead of the rods but can't remember who did it. And yes the rods could be removed without splitting the cases by unscrewing the bolts from the top side.
 
I've worked on a couple of BMW flat twins & often wondered the same thing. Also the same regarding the camshaft. I think Royal Enfield twins had cams that could be removed without splitting the cases but Mr Hopwood didn't seem to think this necessary.
It has to be said that ALL manufactures have some stupid ideas though & my BMW Mystic (stupid name, great bike) has the most ludicrous switch gear. To use the indicators there are three seperate buttons, one for left, one for right, & yet another to cancel them. The Japs sorted switch gear design years ago but BMW had to reinvent the wheel!
 
Matchless said:
I've worked on a couple of BMW flat twins & often wondered the same thing. Also the same regarding the camshaft. I think Royal Enfield twins had cams that could be removed without splitting the cases but Mr Hopwood didn't seem to think this necessary.
It has to be said that ALL manufactures have some stupid ideas though & my BMW Mystic (stupid name, great bike) has the most ludicrous switch gear. To use the indicators there are three seperate buttons, one for left, one for right, & yet another to cancel them. The Japs sorted switch gear design years ago but BMW had to reinvent the wheel!
Click to expand...
Don't some Harley's have a button on the left for left turn and a button on the right for right turns?
This is fine if the rider remembers to mount the motorcycle facing the right way
 
Japs sorted switch gear design years ago but BMW had to reinvent the wheel!

Hello,
Well yes, no doubt they also have their issues. I found out the hard way, when I had to repair a K 100 RT (what a shit, when you have to repair it).
That's why I love my NORTON. But we talked about the conrods, may be also about camshafts:
In my opinion there is no engine as simply designed (which is real engineering) and effective as the BMW /5,/6 and /7 Engines.
Still the NORTON gives more fun with all that beautiful punch, lightness and, well, you know what I mean.
Sorry, let's come back to our NORTON.
Best Regards
Klaus
 
Status
Not open for further replies.

Similar threads

johnm
DHL a winner to New Zealand
Replies
3
Views
742
Shelby-Right
Shelby-Right
S
McLaren Archive: classic New Zealand motor sports footage
Replies
0
Views
1,070
slimslowslider
S
K
New Zealand National rally. [ Auckland shut down because of the bloody virus ]
Replies
11
Views
2,331
gortnipper
gortnipper
Kiwi961
961s in New Zealand
Replies
2
Views
953
ntst8
ntst8
D
961s to New Zealand....
Replies
1
Views
1,666
Time Warp
Time Warp
Back
Top