I DID get another oil pump cable so I'm going to fit that and see if it makes a difference….the one I have from T2 racing doesn’t adjust so the carbs and the pump are perfectly synchronized...it’s close but the pump seems just a little behind the carbs and I don’t think anyone would want that.
I’m doing some cross continent traveling and have a chance to update progress. This time it’s all about the plumbing.
Going to hopefully get rid of this horrible mess…

First of all this….clearly does not connect….

...to this….

I realized that you need a new OEM thermo sensor in the shape of this guy…37750-PCI-004….also common to the ’86 Honda Accord. Whatever works.

Plugged it in to the thermostat housing and thru some heat on it and that temp gauge responded

Before I did that…installed a new OEM thermostat…

And the o-ring…

…first nicely around the edge of the thermostat..

Expansion tank had a bath…
[img]https://photos.smugmug.com/Motorcycles/n-8gc5dS/1989HondaNSR250R/i-GBkLpqB/0/M4n4nwcKxgfXdjS6KGTz3jrnKMZLrbDQmzJ7d4kWm/X2/IMG_2260-X2.jpg [/img]
Silicon hoses came from T2 Racing…via Web!ke for 8255¥…

And they compare with the originals very well…

Only this one needed a trim…

I transferred the extra loops of rubber onto the new pipes.
[img]https://photos.smugmug.com/Motorcycles/n-8gc5dS/1989HondaNSR250R/i-L3CQrqT/0/NKHK32H7KZm2f7gfdbTRL4J54kDhcknWXqc2qxhTn/X2/IMG_2562-X2.jpg…[/img]
Decided the old radiator…

…would be best replaced with this…again from T2 Racing for nearly 30,000¥

