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 Topic: New Member with An MC18...wait.....no...an MC16...yes MC18 







Hudtm60
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Hudtm60 » Thu May 29, 2025 8:23 pm

Those are some wise words Andy. I'm working on getting these on Jauce. Although the year isn't exact- mines a 1988- they certainly look the part.
https://www.jauce.com/auction/t1105599190?allow=1


In the meantime: when you set up your mates in Florida were you basically adjusting the valves so they were flush and out of the way?
To confirm the positioning of my valves if I were to start it (with a remote fuel tank) and manually manipulate the valves via pulling the cables will it be obvious by the engines reaction where the valves are?

In other news, I got a number plate, so we're legal and ready to go!

UPDATE: on a couple of occasions recently when I know you lot are all in bed, or worse, at work, I have resorted to using AI to get some answers and today I got this from ChatGPT

I asked "When the pointers of the RC Valve guides are aligned on a 1988 Honda NSR250R2J MC-18 are the valves flush with the cylinder and not causing any restriction?"

"Yes, when the RC Valve guide pointers are aligned on a 1988 Honda NSR250R2J MC18, the RC (Revolutionary Controlled) Valves should be in the fully open position, meaning the valve shutters are flush with the cylinder exhaust ports and not causing any restriction.

Here’s a more detailed breakdown:

RC Valve alignment marks: The small metal arms or pointers on the RC valve pulley or guides are factory reference points. When they are aligned—typically with matching notches or marks on the casing—it indicates a specific valve position, usually fully open.

Fully open = flush: In the fully open position, the guillotine-style valves retract upward so the exhaust ports are fully exposed—no restriction, just like a traditional two-stroke port.

Closed or partially closed: When the pointers are not aligned (e.g., valves in the low-RPM/closed position), the guillotines partially block the exhaust ports to help with low-end torque.

To confirm:
You can remove the exhaust pipes and visually inspect the RC valves.

When the pointers are aligned, the valve blades should not protrude into the exhaust port—they should be retracted and level with the port roof.

Let me know if you're trying to verify correct cable slack or servo setup as well—those matter for ensuring the RC valves hit the right positions at the right RPM.
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