Circuit board behind speedo

[1300x4_imp]

Hi everyone,
New to the forum, I’ve previously built a CB1300x4 which was sold to a collector locally, he’s looking at purchasing a CB1100 that has been modified to look like a cafe racer from the 60s

It has tomaselli clips, motogadget speedo, Öhlins, 4 into two dunstal style exhaust system etc.

It’s running the standard switch gear.

I was asked to inspect the bike for purchase and with a view to under take further work, upon removing the seat cowl the level of workmanship appears to have fallen into the “out of sight out of mind” methodology

I found the circuit board wrapped in plastic film

Has anyone on here modified their bike and removed the instrument cluster? Is there anything within this circuit board that by removing it would stop the bike from running? Is this the only solution to the problem?

I’ve completed a w800, fuel injected bike and removed the instrument cluster without the need to keep any of the circuit board.

Any advice would be great

[the Ferret]

howdy and welcome to the forum.

Some smart guys will be along shortly.

[max]

Is that the one from botany honda or another cb1100?
And do you mean that the pcb is from the instrument cluster?
From 2014 and onwards there is a shielded white wire running from the cluster to the ecm connector.
The wire is marked; m-txd/rxd on the ecm pin b-24.
To me that means serial comms bi-directional, not sure what the contents of the data is but if they went to the trouble of leaving it inside the bike that could be the reason, apart from that i cannot see a reason why it is still inside the bike, the speedo total mileage is also kept inside the cluster and the hiss unit only talks to the ecm according to the el. diagram.
Replacing a battery , brake fluid reservoir and fusebox access would be my concern apart from the uncomfortable seat.
Cheers and welcome.

[GoldOxide_imp]

While you wait 1300x4, welcome to the Forum!

[Cormanus]

Welcome 1300x4.

[Lord Popgun]

Max, that is the bi-directional serial data line. I've posted the info it carries somewhere on here. It is in the manual too. With this disconnected you will get a MIL and no speed data to the ECU. I forget what else.

[max]

Thanks Lord Popgun, thinking about that i guess the mpg readout runs probably over the serial line too.

1300x4 having worked on a 1300 you would know how similar the engine is apart from the cylinders, are they identical?