Oversize exhaust nuts

[medat727]

I have recently acquired a Norvin project that has a rear head with an exhaust port that has been machined to a size of 2.0" x 20 TPI, the front head has had the brass insert installed as is outlined in KTB bringing it to a standard 1.88 x 20 TPI, it appeares as though the lack of a rear insert was intentional as the engine has been rebuilt and is propperly mounted in it's frame. My question is, does anyone make an oversized exhaust nut to fit the 2.0 x 20TPI and if so does this pose a threat with the thinner wall of the port?

Thanks

 

[clevtrev]

I have recently acquired a Norvin project that has a rear head with an exhaust port that has been machined to a size of 2.0" x 20 TPI, the front head has had the brass insert installed as is outlined in KTB bringing it to a standard 1.88 x 20 TPI, it appeares as though the lack of a rear insert was intentional as the engine has been rebuilt and is propperly mounted in it's frame. My question is, does anyone make an oversized exhaust nut to fit the 2.0 x 20TPI and if so does this pose a threat with the thinner wall of the port?

Thanks

Doubt it, but I have an insert that will bring it back to standard.

 

[medat727]

Will your insert thread into my existing 2.0 x 20TPI or will I need to machine the port to fit?

 

[vibrac]

I just get an insert or a nut to fit what ever is easiest I dont think that any of my bikes have a standard one try Roger Forsyth at ROFOR Engineering in the city of a thousand roundabouts Milton Keynes 01908 375225

 

[Puddle jumper]

Hi,
I made oversized nuts for my HRD chop so I could run 2" exhausts and repair damage to one head. To do this I made up a stepped reducer that screws into the existing exhaust thread (which was machined to a minimum oversize to effect a repair) and then steps up to cope with the 2" pipe. It worked well; I have post some pictures so you can see,

Cheers Paul

 

[medat727]

Paul,
Thanks for the post, I'm going to go with a brass insert and standard nuts.

David