Speedometer issue

The barn find is up and running great! It sounds fantastic and looks good too! I am now to the "test drive and see what needs tweaking" phase. The only problem I've identified so far (and it's minor) is an interesting situation with the speedometer: When I accelerate, the speedo needle rises smoothly and consistently, but it rises slower than the rate at which I am accelerating. The same happens when I slow down. It's like it takes a second to catch up. I hope I am accurately describing what is taking place here. If I rapidly accelerate to what I estimate to be about 55 MPH, when I look at the speedo, it's rising, but it's only at about 35. It takes about 1/2 a second to get caught up.

What might be the issue here? The cable has been lubricated, so I don't think the problem could be there.

 

The instrument(s) need service: http://xjbikes.com/Forums/viewtopic/t=15303.html

 

You've explained it simply enough. I had a similar problem with my 550 last spring, and when I took it to service in the kitchen my cumbersome hands weren't delicate enough while cleaning the instruments. Somehow I managed to get the spring for tachometer too loose with too much lubrication or else stretched the spring too much (?) I don't know... wound up getting a replacement unit really cheap and learned my lesson. Take the service seriously and don't screw up the needles, haha