One thing I have noticed on my bike, that I did not notice on previous VFR1200s I've ridden is that as you let the clutch out while in gear, the revs rise a few hundred rpm. Probably some misguided attempt to 'assist' the rider in some way, but even more annoying when I currently have an idle speed problem with it racing at 3K rpm. However, the fact that I've not noticed it on other bikes may indicate a problem there. Or maybe I've simply forgotten about those other bikes or maybe when tick over is normal, you don't notice it.
Can anyone please confirm that this is normal and the revs do rise slightly as you let out the clutch when in gear?
I've never notice do that on mine.
i think that that bike is haunted !!!
This rise in engine speed is definitely initiated by the clutch switch, but I have now found that it is not due to the throttle butterflies opening further. With the bike on the stand, engine running, in gear and watching the butterflies, they do NOT move as I let the clutch in and out, but the engine speed changes by several hundred rpm.
So if it's not being done by the throttles, it must be ignition timing. As you let the clutch out in gear it advances the timing, probably to the normal correct running value. I can only assume retarding the ignition in this way while not being driven in some way improves emissions or some other aspect of the running of the engine. I guess this doesn't altogether surprise me.
But why does no-one else notice it? Well, I currently have a problem of the engine idling at 3K rpm, whereas normally this would be about 1100 rpm and it occurs to me that a change in ignition timing at that low rpm would not make such a big difference in engine speed, indeed, possibly not even noticeable. But an engine that is already spinning at 3K rpm, it is likely to have a much greater impact and hence a noticeable rise in engine speed.
In fact, maybe it switches the whole timing curve, so at low rpm there is no change, but it simply advances at a faster rate as the revs rise. So under normal circumstances at the correct idle speed, there is NO change. But because my engine is already spinning at 3K rpm the timing curve switch causes a sudden advance, hence the noticeable rise in rpm.
Either way, I'm thinking it's unlikely this is a fault with my bike, just that the actual problem (too fast idle) is exacerbating and obfuscating the clutch/timing issue.
Unless anyone has anything more definitive on this, I will assume there is no actual problem here.
I have heard from several other people who have experienced this same rise in rpm as you let in the clutch (i.e. let the lever out) on other Hondas. But now my tickover is back to normal, I simply haven't noticed it, so I'm sure it is as I surmised earlier, it only becomes apparent when the engine is running too fast.
Every honda I've ever owned does it. From what I've read its to aid in take off from full stop.
I've owned Hondas since 1969, currently have about half a dozen of them and I used to work for Honda UK and this is the first time I've come across it. You must have owned those that do it, but no other VFR1200 owner seems to have noticed it - except you it would now appear.
Still, my original question has been answered thanks.
My 07 CBR600RR had the idle rpm rise with the releasing of the clutch lever.