Ducati Monster Forum

Moto Board => Tech => Topic started by: bond0087 on September 22, 2011, 11:30:53 PM

Title: Normal tach fluctuation at constant engine speed
Post by: bond0087 on September 22, 2011, 11:30:53 PM
I have a 2000 m750, and I've never cared much for the instrument panel that came with the early Monsters, so when I saw a 2001 900ie instrument cluster on eBay for a reasonable price I jumped on it. I installed it yesterday, and the tach is a bit disappointing. It jumps by at least 500rpm around the speed the engine is actually going, constantly jumping and never giving a steady reason. The text on the gauge should say "x1000 sec^-1 +/- 500" what level of jumpy-ness is usual, and what can I do about it? I've seen some say that it's a flaky ground on the board, but how do I get at the circuit? Do I have to take the guage apart from the bezel or can i take it apart from the rear? I tried to take the speedo that came with this apart mostly out of curiosity and I made a mess of the bezel; I'm not sure I want the tach to suffer a similar fate. Any advice or comments on how the tach should perform would be appreciated.
Thanks!
Title: Re: Normal tach fluctuation at constant engine speed
Post by: hillbillypolack on September 23, 2011, 09:07:33 AM
I'm not familiar with your specific tach, but on my M900 (1996), the tach movement was more or less a factor of its connection to the electrics.  Meaning that it may not be in the tach itself, but its connection in the battery area (if I recall).  The tach reads either the flywheel or coil pulses unless I'm way way off base.

I'd do a search on tachs, phone up some parts shops and see what you can find out.