The motorcycle thread

Pretty much the penultimate instalment of my life with this VFR. Had a really deep root around the wiring loom. Discovered a non-OEM relay that looks like it had been used to run some additional lights at some time in the bike’s previous life. Didn’t seem to be causing any issues but it was grounded to the main negative ground point, so removed it and gave it a good clean.

Then realised that there is an additional ecu on this bike that is not on any wiring diagram that I have seen. Turns out it’s a separate ignition unit only on JDM model bikes.

I simply can’t get replacement crank pulse generators; they are unobtanium. Quite a few peeps on the various VFR forums seemed to suggest that them being faulty and causing all 4 cylinders to drop out at the same time is highly unlikely so they are probably not faulty.

Took loads of old insulating tape off the harness, so it looks like someone has been here before me, but I couldn’t see any major issues and just gave all the connector terminals a good clean and checked continuity where I could.

So the plan is to send off the spark units for testing and if needs be, repaired. Reassemble the bike and try one last time. If it fails on me again then it’s a new bike at the start of the summer holidays and I will sell the VFR.


Last time I went out on the Dax it kept bogging down and stopping before restarting easily and running for a few minutes before the same cycle repeated.
I suspected something with the float bowl so took the carb off and cleaned everything.
Took it out for a spin this morning and it was running sweet as. I enjoyed it so much I dragged it out again for another quick blatt this afternoon.

Ps. If you look closely you can see an asthmatic glow worm in the headlight meaning I seem to have the wiring sorted too. :crossed_fingers:


I’ve had a little bit of a revelation. Not sure it will help with the cutting out, but might do. I’ve found out today that the second little ECU box that’s not on any wiring diagram I’ve seen, restricted these bikes to 77hp (from105hp) with this second ECU. The safety conscious Japanese didn’t like the bikes that they actually sold in Japan being able to go too fast!

The good news is I have managed to find a reconditioned uk market spark unit, which will unrestrict the bike and do-away with a load of connections. Also, it’s £80 cheaper than getting my 2 spark units tested. Winner. Maybe. Still planning on selling the bike if if cuts out.




Any update @wheezy ?

:point_up:t3:Bought the refurbished spark unit and a new cam sensor has arrived, so over the weekend I’m hoping to sort out the wiring to remove the speed limiting ECU and get it all plumbed back together. Work and home are a bit busy at the moment so might not get it completely finished, but hopefully have the bike running.

Simply couldn’t get replacement crank sensors, but the more I’ve looked into them and what’s been happening with the bike, I don’t think that’s the issue anyway. Will have another look over the loom and when I get the engine running I’m going to give all the connections a little test to see if there are any loose connections (I don’t think there are!).


New spark unit wired in and the speed limiter ECU taken out. Wired it up according to some instructions I had and the bike fired up ok, so, so far, so good. I had a big tidy up of the loom, wrapping it with new cloth tape and making sure it was all routed correctly and not moving anywhere. I’m a lot happier with it. Not sure I’ve got time to take her out for a spin, but will try to get her out this week.


Good luck. :crossed_fingers:

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I’m at Loomies, give her a test ride :grin:


Spotted this at Bushy and thought of you bikers, the yellow looked nice and lairy!


Nice, l;ooks like a Gen 5, :+1:t2:

There’s a bike meet started at Ockham Bites, a cafe on the M25. They’ve been hit really hard by the A3/M25 junction roadworks, so thought I’d pop along. Went with a mate from work who’s got a rather nice VTR. A lovely evening for it.


Bike running ok mate?

At the moment, yes. But I’m not counting my chickens yet. Just going to ride it and enjoy it.