Hi guys I have had my nsr in peices for about ten years, procrastinating and gathering parts, I finally came to put it back together and found this while cleaning up the crank cases. https://youtu.be/q6N2ZxcGGpw

I uploaded a vid showing the notches on the crank cases where the bearing locating pins sit. One is ok, still square one has a small amount of damage and the third one looks quite misshapen from the bearing moving and the opposing part on the top casing has a small amount of damage.

Please watch the video and any advice would be greatly appreciated. Thank you all in advance. Regards Dave Roberts

Hi dave robbo,

The concern is that if the bearing locating pins don’t sit snug/correctly then the bearings could spin inside the crankcases and cause more damage.

I would personally show them to some specialist welders and machining shops before giving up on them.

Good luck.

I'd strongly advise against using the cases in their current state. While it may have been running "OK" up the point of when it was torn down (crank failure... restoration project?), and may be OK if reassembled, it's only a matter of time before more serious damage occurs.

The cases are repairable by a good engineering company. Here's a set we did that had exactly the same problem.



We also line-bored and honed the crankcase halves to ensure roundness.
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Andy.
NSR-WORLD.COM

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Thanks for the advice guys, it's not what I was hoping to here but it is what it is! It's only been ten years so I guess there's no rush!

Hi Andy could you let me know how much the case repair cost and the shop name that did the work, it looks great like new!

I also have some questions as to what exactly the pins on the crank are there to do, they only seem to lock the bearings when the crank bearings fail and try to spin, then the pin digs in to the crankcase. Are they to stop the bearing from completely spinning and destroying its seat?

One other thing when installing the crank if they are just for locating the crank, with the pins being round and smaller than the notch they sit in, do you just centralise the pin in the notch or have it touching one side of the notch. One of the above comments says it should be snug in the notch. I don't know exactly what that means the pins are much smaller that the notches and I can't see how it would fit snugly unless they were matching shapes and size?

One last thing can I use mix match enging caseing halves from different engines?

Thanks for the help! I hope I'm naerly at the bottom of the rabbit hole

Hi I just read your reply again and saw it was your shop that did the repair, could you quote me on the repairs for my case's here is another video with a bit of a better look. https://youtu.be/r9ILYqE2eGY

I'm in Australia but have family visiting from the UK I'm a couple of months, I may be able to get them to take the cases home with them then locally post them to you. Where abouts are you located? Thanks regards David

dave robbo wrote:
Hi I just read your reply again and saw it was your shop that did the repair, could you quote me on the repairs for my case's here is another video with a bit of a better look. https://youtu.be/r9ILYqE2eGY

I'm in Australia but have family visiting from the UK I'm a couple of months, I may be able to get them to take the cases home with them then locally post them to you. Where abouts are you located? Thanks regards David

Drop Steve Performance Engineering a line, via Facebook if you use it as he monitors it frequently, and he should be able to sort you out. I no longer work for GTPE, but I still drive traffic there, and hand-on-heart couldn't recommend anyone else more highly.

Technically, you should/could be able to mix upper and lower case halves if you have them faced and line bored, but personally, I'd strongly advise against it.
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Andy.
NSR-WORLD.COM

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Thanks Andy