Girder Fork Yoke

[pushrodtwin]

I have machined the alloy yoke to replace the old malleable iron item. The new one has altered geometry as a safety upgrade to prevent the motorcycle from having tank slappers. 

Do I need to have it certified?

Attachments:

[Chris]

Apr 12, 2024 15:43:19 GMT 12 pushrodtwin said:

I have machined the alloy yoke to replace the old malleable iron item. The new one has altered geometry as a safety upgrade to prevent the motorcycle from having tank slappers. 

Do I need to have it certified?

Gidday

vehicleinspection.nzta.govt.nz/virms/in-service-wof-and-cof/motorcycles/steering-and-suspension/steering-and-suspension-systems#tab2 is the threshold in the VIRM which lists the steering and suspension modifications that do not require certification, there is no fork yoke listed there, so that would mean that it does require certification.

Cheers

Chris

[pushrodtwin]

Apr 15, 2024 8:26:07 GMT 12 Chris said:

Apr 12, 2024 15:43:19 GMT 12 pushrodtwin said:

I have machined the alloy yoke to replace the old malleable iron item. The new one has altered geometry as a safety upgrade to prevent the motorcycle from having tank slappers. 

Do I need to have it certified?

Gidday

vehicleinspection.nzta.govt.nz/virms/in-service-wof-and-cof/motorcycles/steering-and-suspension/steering-and-suspension-systems#tab2 is the threshold in the VIRM which lists the steering and suspension modifications that do not require certification, there is no fork yoke listed there, so that would mean that it does require certification.

Cheers

Chris

Thanks Chris. What are the criteria for certification, what will the certifier need? 

[Chris]

Apr 18, 2024 20:32:52 GMT 12 pushrodtwin said:

Apr 15, 2024 8:26:07 GMT 12 Chris said:

Gidday

vehicleinspection.nzta.govt.nz/virms/in-service-wof-and-cof/motorcycles/steering-and-suspension/steering-and-suspension-systems#tab2 is the threshold in the VIRM which lists the steering and suspension modifications that do not require certification, there is no fork yoke listed there, so that would mean that it does require certification.

Cheers

Chris

Thanks Chris. What are the criteria for certification, what will the certifier need? 

Hi

As always, the best suggestion is to take it to your certifier first, as they are the ones that will have to sign it off.
But I imagine for this yoke, they will want a list of the materials you used, they will also want to inspect it closely for welds, method of attachment etc. 

Regards

Chris

[pushrodtwin]

Thanks, I was hoping for some definitive guide lines before traipsing off down half the length of the south Island to the nearest certifier. 
How is the new Motor Cycle Standard progressing? How is this covered in the new standard?

[Chris]

Apr 23, 2024 8:03:56 GMT 12 pushrodtwin said:

Thanks, I was hoping for some definitive guide lines before traipsing off down half the length of the south Island to the nearest certifier. 
How is the new Motor Cycle Standard progressing? How is this covered in the new standard?

Hi

The draft standard is still in progress and is currently with certifiers for them to reference but it does not have a specific recipe for creating a steering yoke other than to say.

It must be fabricated from suitable material and be designed for the axle weight and steering loads of the motorcycle being constructed or modified.

Depending on the grade of aluminium, it can be less than ideal for components subjected to high cyclic loads as aluminium is prone to fatigue.

As there is very little information provided, it is hard to pick what aspects to advise you on and as the standard is only in draft, I am unable to point you to a copy of it on our website.

Regards

Chris