Is this the correct cottered cradle for pre-Mk3 models?

Status
Not open for further replies.
Joined
May 8, 2022
Messages
911
Country flag

I'm sure 06-6972 is the correct part but this starts 'Z'. What does Z indicate?

06-6972 shows on their own website but supplied bare.

Both AN and RGM are showing out of stock.
 

I'm sure 06-6972 is the correct part but this starts 'Z'. What does Z indicate?

06-6972 shows on their own website but supplied bare.

Both AN and RGM are showing out of stock.
Yes it is the correct part, & I've just taken delivery of the very same for a friends MK2a I'm currently building. I've been calling Andover regularly to find out when they would be in stock, & they kept telling me a couple of weeks. When I called them again last week they said two months due to supply problems.
As I could not wait any longer I ordered the Norvil one. If you wait until tomorrow I will let you know how good/bad it is. I have no doubt that being from Norvil it will be MY fault if it's faulty. Watch this space!

Martyn.
 
Why spend $500 on a part that is no better than a stock cradle with full circumference split collar clamps unlike cotter pins that rely on the thin wall tube to not oval.
Something the collar clamps avoid but seems to be a more familiar modification in the USA being the (mod) origin.

IMG_3707 - Copy.jpg
thumbnail_file-27.jpg


The Z within a part number seems to be the sign of a non factory part with many marques so not just Norton.
 
Yes it is the correct part, & I've just taken delivery of the very same for a friends MK2a I'm currently building. I've been calling Andover regularly to find out when they would be in stock, & they kept telling me a couple of weeks. When I called them again last week they said two months due to supply problems.
As I could not wait any longer I ordered the Norvil one. If you wait until tomorrow I will let you know how good/bad it is. I have no doubt that being from Norvil it will be MY fault if it's faulty. Watch this space!

Martyn.
Hey buddy I have a MK 11 A cradle for you free . ( O.K. maybe beer ) Original and not wallowed out . P.M. me but shipping on you. Gift.
 
DRIVE ALL THE WAY HOME WITH A STEEL HAMMER .

Just in case you were wondering about whichwas the correct way to install a Cotter Bolt ! no mucking around . ;)

Is this the correct cottered cradle for pre-Mk3 models?
 
With 'Steel hammer' is the carry over advice, good for kickstart or engine cradle swingarm cotter pins. Especially with today's softer bicycle cotters where if you use the nut to pull the pin into position ends up with stripped threads.
 
Why spend $500 on a part that is no better than a stock cradle with full circumference split collar clamps unlike cotter pins that rely on the thin wall tube to not oval.
Something the collar clamps avoid but seems to be a more familiar modification in the USA being the (mod) origin.

View attachment 96734 View attachment 96735

The Z within a part number seems to be the sign of a non factory part with many marques so not just Norton.
Warp,
I have used the split collars for years and everything stays nice. I can’t fault them in any way.
Mike
 
The Mk3 cotters only need to be tight enough to lock the spindle to the cradle tube, not so tight as when securing a kickstart lever to a shaft.

Hitting the Mk3 type cotters with a hammer of any description I think would be extremely difficult (without a drift also swinging a hammer in that area is all but impossible) because the cotters locate inside the cotter tubes far enough down to fit the "Cotter seal plugs" (Item 2x 11).

 
As has been mentioned I think by komando? If you use these split collar clamps there is no need to drill holes in the support tube for the centre bolts
The pressure of the bolts on the tube should be enough
Plus the oil can't leak out
 
As has been mentioned I think by kommando? If you use these split collar clamps there is no need to drill holes in the support tube for the centre bolts
I did mention this as on my MK2a which had no movement the split clamps are on with no holes drilled and the handling did improve slightly. However for another build I got a cradle where the tube is reamed out 5 thou to cure the belled out ends. When I put a standard sized pin into the cradle and add split collar clamps then the clearance does not change even with the split clamp bolts fully torqued, there is still a small gap at the split so this is not the issue. So based on that experiment the drilled holes are needed if the cradle tube is compromised in any way which allows movement, no holes are needed if there is no movement.
 
I did mention this as on my MK2a which had no movement the split clamps are on with no holes drilled and the handling did improve slightly. However for another build I got a cradle where the tube is reamed out 5 thou to cure the belled out ends. When I put a standard sized pin into the cradle and add split collar clamps then the clearance does not change even with the split clamp bolts fully torqued, there is still a small gap at the split so this is not the issue. So based on that experiment the drilled holes are needed if the cradle tube is compromised in any way which allows movement, no holes are needed if there is no movement.
....and I used Grade 8 HHCS instead of the set (grub) screws shown above, to allow getting them to "RFT" spec.
 
I did mention this as on my MK2a which had no movement the split clamps are on with no holes drilled and the handling did improve slightly. However for another build I got a cradle where the tube is reamed out 5 thou to cure the belled out ends. When I put a standard sized pin into the cradle and add split collar clamps then the clearance does not change even with the split clamp bolts fully torqued, there is still a small gap at the split so this is not the issue. So based on that experiment the drilled holes are needed if the cradle tube is compromised in any way which allows movement, no holes are needed if there is no movement.
Did you try grinding the bolts to a point to reduce the clamping area?
 
Did you try grinding the bolts to a point to reduce the clamping area?
It was an experiment to see how much the clamps alone could squeeze the tube, I was not expecting the whole 5 thou to disappear but neither was I expecting no movement at all. If I tried to squeeze the tube using pointed or unpointed bolts the a 5 thou over size pin would not be able to enter the tube. When I get a 5 thou oversize pin I will rerun the experiment before drilling the holes, the cradle is not attached to a bike so easy to drill.
 
  • Like
Reactions: baz
As I should have known! The bloody thing is shit. The rubbing faces for the s/arm bushes are 0.025" out of parallel. Also, the pin bore looks like it was reamed without lube at one end. Looking at the heat marks it appears to have been machined BEFORE it was welded as opposed to the proper way of doing things.
I called Norvil & spoke to a very polite chap who said it will be collected by the courier, then Les will check another on Thursday & send it out. This could be fun. Update to follow.
By the way, the only reason for buying one in the first place is because I don't have one to recon. & modify.
 
As I should have known! The bloody thing is shit. The rubbing faces for the s/arm bushes are 0.025" out of parallel. Also, the pin bore looks like it was reamed without lube at one end. Looking at the heat marks it appears to have been machined BEFORE it was welded as opposed to the proper way of doing things.
I called Norvil & spoke to a very polite chap who said it will be collected by the courier, then Les will check another on Thursday & send it out. This could be fun. Update to follow.
By the way, the only reason for buying one in the first place is because I don't have one to recon. & modify.

Martin, did you read post #6 ?
 
Status
Not open for further replies.
Back
Top